Articles | Volume 19, issue 7
https://doi.org/10.5194/acp-19-4615-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-19-4615-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
08 Apr 2019
Research article |
| 08 Apr 2019
| 08 Apr 2019
From weak to intense downslope winds: origin, interaction with boundary-layer turbulence and impact on CO2 variability
Departamento de Física de la Tierra y Astrofísica, Universidad Complutense de Madrid, Madrid, Spain
Invited contribution by Jon Ander Arrillaga, recipient of the EGU Nonlinear Processes in Geosciences Outstanding Student Poster Award 2015.
Carlos Yagüe
Departamento de Física de la Tierra y Astrofísica, Universidad Complutense de Madrid, Madrid, Spain
Carlos Román-Cascón
Departamento de Física de la Tierra y Astrofísica, Universidad Complutense de Madrid, Madrid, Spain
Laboratoire d'Aérologie, CNRS, Université de Toulouse, CNRS, UPS, Toulouse, France
Mariano Sastre
Departamento de Física de la Tierra y Astrofísica, Universidad Complutense de Madrid, Madrid, Spain
Maria Antonia Jiménez
Departament de Física, Universitat de les Illes Balears, Palma, Spain
Gregorio Maqueda
Departamento de Física de la Tierra y Astrofísica, Universidad Complutense de Madrid, Madrid, Spain
Jordi Vilà-Guerau de Arellano
Meteorology and Air Quality Group, Wageningen University, Wageningen, the Netherlands
Related authors
No articles found.
Jordi Vilà-Guerau de Arellano, Roderick Dewar, Kim A. P. Faassen, Teemu Hölttä, Remco de Kok, Ingrid T. Luijkx, and Timo Vesala
EGUsphere, https://doi.org/10.5194/egusphere-2025-2705, https://doi.org/10.5194/egusphere-2025-2705, 2025
This preprint is open for discussion and under review for Biogeosciences (BG).
Short summary
Short summary
This study explores how oxygen moves through tiny pores in leaves, especially when water vapor is also flowing out. We show that under common conditions, oxygen can move from the leaf to the air even when its concentration is higher outside – a surprising effect. Our findings help explain oxygen exchange in still air and support better models of plant–atmosphere interactions.
Marc Castellnou Ribau, Mercedes Bachfischer, Marta Miralles Bover, Borja Ruiz, Laia Estivill, Jordi Pages, Pau Guarque, Brian Verhoeven, Zisoula Ntasiou, Ove Stokkeland, Chiel Van Herwaeeden, Tristan Roelofs, Martin Janssens, Cathelijne Stoof, and Jordi Vilà-Guerau de Arellano
EGUsphere, https://doi.org/10.5194/egusphere-2025-1923, https://doi.org/10.5194/egusphere-2025-1923, 2025
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
Firefighter entrapments can occur when wildfires escalate suddenly due to fire-atmosphere interactions. This study presents a method to analyze this in real-time using two weather balloon measurements: ambient and in-plume conditions. Researchers launched 156 balloons during wildfire seasons in Spain, Chile, Greece, and the Netherlands. This methodology detects sudden changes in fire behavior by comparing ambient and in-plume data, ultimately enhancing research on fire-atmosphere interactions.
Sreehari Kizhuveettil, Jordi Vila-Guerau de Arellano, Martina Krämer, Armin Afchine, Luiz A. T. Machado, Martin Zöger, and Wiebke Frey
EGUsphere, https://doi.org/10.5194/egusphere-2025-1637, https://doi.org/10.5194/egusphere-2025-1637, 2025
Short summary
Short summary
Aircraft measurements are used to investigate high-altitude downdrafts in tropical deep convective clouds. The cloud water present in the downdrafts and its intensity do not show any correlation. Surprisingly, downdrafts occurred in supersaturated regions, contradicting the classical view of subsaturated downdrafts. Up- and downdrafts of similar strength show similar particle size distributions. These findings shed new light on the interplay between deep convection dynamics and microphysics.
Robbert Petrus Johannes Moonen, Getachew Agmuas Adnew, Jordi Vilà-Guerau de Arellano, Oscar Karel Hartogensis, David Joan Bonell Fontas, Shujiro Komiya, Sam P. Jones, and Thomas Röckmann
EGUsphere, https://doi.org/10.5194/egusphere-2025-452, https://doi.org/10.5194/egusphere-2025-452, 2025
Short summary
Short summary
Understory ejections are distinct turbulent features emerging in prime tall forest ecosystems. We share a method to isolate understory ejections based on H2O-CO2 anomalie quadrants. From these, we calculate the flux contributions of understory ejections and all flux quadrants. In addition we show that a distinctly depleted isotopic composition can be found in the ejected water vapour. Finally, we explored the role of clouds as a potential trigger for understory ejections.
Leon Geers, Ruud Janssen, Gudrun Thorkelsdottir, Jordi Vilà-Guerau de Arellano, and Martijn Schaap
EGUsphere, https://doi.org/10.5194/egusphere-2025-426, https://doi.org/10.5194/egusphere-2025-426, 2025
Short summary
Short summary
High-resolution data on reactive nitrogen deposition are needed to inform cost-effective policies. Here, we describe the implementation of a dry deposition module into a large eddy simulation code. With this model, we are able to represent the turbulent exchange of tracers at the hectometer resolution. The model calculates the dispersion and deposition of NOx and NH3 in great spatial detail, clearly showing the influence of local land use patterns.
Felipe Lobos-Roco, Jordi Vilà-Guerau de Arellano, and Camilo del Río
Hydrol. Earth Syst. Sci., 29, 109–125, https://doi.org/10.5194/hess-29-109-2025, https://doi.org/10.5194/hess-29-109-2025, 2025
Short summary
Short summary
Water resources are fundamental for the social, economic, and natural development of (semi-)arid regions. Precipitation decreases due to climate change obligate us to find new water resources. Fog harvesting (FH) emerges as a complementary resource in regions where it is abundant but untapped. This research proposes a model to estimate FH potential in coastal (semi-)arid regions. This model could have broader applicability worldwide in regions where FH could be a viable water source.
Arseniy Karagodin-Doyennel, Fredrik Jansson, Bart van Stratum, Hugo Denier van der Gon, Jordi Vilà-Guerau de Arellano, and Sander Houweling
EGUsphere, https://doi.org/10.5194/egusphere-2024-3721, https://doi.org/10.5194/egusphere-2024-3721, 2024
Short summary
Short summary
We introduce a new simulation platform based on the Dutch Large-Eddy Simulation (DALES) to simulate carbon dioxide (CO2) emissions and their dispersion in the turbulent environments with hectometer resolution. This model incorporates both anthropogenic emission inventory and ecosystem exchanges. Simulation results for the main urban area in the Netherlands demonstrate a strong potential of DALES to enhance CO2 emission modeling, which is important for refining their reduction strategies.
Mary Rose Mangan, Jordi Vilà-Guerau de Arellano, Bart J. H. van Stratum, Marie Lothon, Guylaine Canut-Rocafort, and Oscar K. Hartogensis
EGUsphere, https://doi.org/10.5194/egusphere-2024-3000, https://doi.org/10.5194/egusphere-2024-3000, 2024
Short summary
Short summary
Using observations and high-resolution turbulence modeling, we examine the influence of irrigation-driven surface heterogeneity on the atmospheric boundary layer (ABL). We employ different spatial scales of heterogeneity to explore how the influence of surface heterogeneity on the ABL within a single grid cell would change in higher resolution global models. We find that the height of the ABL is highly variable, and that the surface heterogeneity is felt least strongly in the middle of the ABL.
Luiz A. T. Machado, Jürgen Kesselmeier, Santiago Botía, Hella van Asperen, Meinrat O. Andreae, Alessandro C. de Araújo, Paulo Artaxo, Achim Edtbauer, Rosaria R. Ferreira, Marco A. Franco, Hartwig Harder, Sam P. Jones, Cléo Q. Dias-Júnior, Guido G. Haytzmann, Carlos A. Quesada, Shujiro Komiya, Jost Lavric, Jos Lelieveld, Ingeborg Levin, Anke Nölscher, Eva Pfannerstill, Mira L. Pöhlker, Ulrich Pöschl, Akima Ringsdorf, Luciana Rizzo, Ana M. Yáñez-Serrano, Susan Trumbore, Wanda I. D. Valenti, Jordi Vila-Guerau de Arellano, David Walter, Jonathan Williams, Stefan Wolff, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 8893–8910, https://doi.org/10.5194/acp-24-8893-2024, https://doi.org/10.5194/acp-24-8893-2024, 2024
Short summary
Short summary
Composite analysis of gas concentration before and after rainfall, during the day and night, gives insight into the complex relationship between trace gas variability and precipitation. The analysis helps us to understand the sources and sinks of trace gases within a forest ecosystem. It elucidates processes that are not discernible under undisturbed conditions and contributes to a deeper understanding of the trace gas life cycle and its intricate interactions with cloud dynamics in the Amazon.
Tanguy Lunel, Maria Antonia Jimenez, Joan Cuxart, Daniel Martinez-Villagrasa, Aaron Boone, and Patrick Le Moigne
Atmos. Chem. Phys., 24, 7637–7666, https://doi.org/10.5194/acp-24-7637-2024, https://doi.org/10.5194/acp-24-7637-2024, 2024
Short summary
Short summary
During the summer in Catalonia, a cool wind, the marinada, blows into the eastern Ebro basin in the afternoon. This study investigates its previously unclear dynamics using observations and a meteorological model. It is found to be driven by a cool marine air mass that flows over the mountains into the basin. The study shows how the sea breeze, upslope winds, larger weather patterns and irrigation play a prominent role in the formation and characteristics of the marinada.
Kim A. P. Faassen, Jordi Vilà-Guerau de Arellano, Raquel González-Armas, Bert G. Heusinkveld, Ivan Mammarella, Wouter Peters, and Ingrid T. Luijkx
Biogeosciences, 21, 3015–3039, https://doi.org/10.5194/bg-21-3015-2024, https://doi.org/10.5194/bg-21-3015-2024, 2024
Short summary
Short summary
The ratio between atmospheric O2 and CO2 can be used to characterize the carbon balance at the surface. By combining a model and observations from the Hyytiälä forest (Finland), we show that using atmospheric O2 and CO2 measurements from a single height provides a weak constraint on the surface CO2 exchange because large-scale processes such as entrainment confound this signal. We therefore recommend always using multiple heights of O2 and CO2 measurements to study surface CO2 exchange.
Raquel González-Armas, Jordi Vilà-Guerau de Arellano, Mary Rose Mangan, Oscar Hartogensis, and Hugo de Boer
Biogeosciences, 21, 2425–2445, https://doi.org/10.5194/bg-21-2425-2024, https://doi.org/10.5194/bg-21-2425-2024, 2024
Short summary
Short summary
This paper investigates the water and CO2 exchange for an alfalfa field with observations and a model with spatial scales ranging from the stomata to the atmospheric boundary layer. To relate the environmental factors to the leaf gas exchange, we developed three equations that quantify how many of the temporal changes of the leaf gas exchange occur due to changes in the environmental variables. The novelty of the research resides in the capacity to dissect the dynamics of the leaf gas exchange.
Ruben B. Schulte, Jordi Vilà-Guerau de Arellano, Susanna Rutledge-Jonker, Shelley van der Graaf, Jun Zhang, and Margreet C. van Zanten
Biogeosciences, 21, 557–574, https://doi.org/10.5194/bg-21-557-2024, https://doi.org/10.5194/bg-21-557-2024, 2024
Short summary
Short summary
We analyzed measurements with the aim of finding relations between the surface atmosphere exchange of NH3 and the CO2 uptake and transpiration by vegetation. We found a high correlation of daytime NH3 emissions with both latent heat flux and photosynthetically active radiation. Very few simultaneous measurements of NH3, CO2 fluxes and meteorological variables exist at sub-diurnal timescales. This study paves the way to finding more robust relations between the NH3 exchange flux and CO2 uptake.
Robbert P. J. Moonen, Getachew A. Adnew, Oscar K. Hartogensis, Jordi Vilà-Guerau de Arellano, David J. Bonell Fontas, and Thomas Röckmann
Atmos. Meas. Tech., 16, 5787–5810, https://doi.org/10.5194/amt-16-5787-2023, https://doi.org/10.5194/amt-16-5787-2023, 2023
Short summary
Short summary
Isotope fluxes allow for net ecosystem gas exchange fluxes to be partitioned into sub-components like plant assimilation, respiration and transpiration, which can help us better understand the environmental drivers of each partial flux. We share the results of a field campaign isotope fluxes were derived using a combination of laser spectroscopy and eddy covariance. We found lag times and high frequency signal loss in the isotope fluxes we derived and present methods to correct for both.
Kim A. P. Faassen, Linh N. T. Nguyen, Eadin R. Broekema, Bert A. M. Kers, Ivan Mammarella, Timo Vesala, Penelope A. Pickers, Andrew C. Manning, Jordi Vilà-Guerau de Arellano, Harro A. J. Meijer, Wouter Peters, and Ingrid T. Luijkx
Atmos. Chem. Phys., 23, 851–876, https://doi.org/10.5194/acp-23-851-2023, https://doi.org/10.5194/acp-23-851-2023, 2023
Short summary
Short summary
The exchange ratio (ER) between atmospheric O2 and CO2 provides a useful tracer for separately estimating photosynthesis and respiration processes in the forest carbon balance. This is highly relevant to better understand the expected biosphere sink, which determines future atmospheric CO2 levels. We therefore measured O2, CO2, and their ER above a boreal forest in Finland and investigated their diurnal behaviour for a representative day, and we show the most suitable way to determine the ER.
Micael Amore Cecchini, Marco de Bruine, Jordi Vilà-Guerau de Arellano, and Paulo Artaxo
Atmos. Chem. Phys., 22, 11867–11888, https://doi.org/10.5194/acp-22-11867-2022, https://doi.org/10.5194/acp-22-11867-2022, 2022
Short summary
Short summary
Shallow clouds (vertical extent up to 3 km height) are ubiquitous throughout the Amazon and are responsible for redistributing the solar heat and moisture vertically and horizontally. They are a key component of the water cycle because they can grow past the shallow phase to contribute significantly to the precipitation formation. However, they need favourable environmental conditions to grow. In this study, we analyse how changing wind patterns affect the development of such shallow clouds.
Carlos Calvo-Sancho, Javier Díaz-Fernández, Yago Martín, Pedro Bolgiani, Mariano Sastre, Juan Jesús González-Alemán, Daniel Santos-Muñoz, José Ignacio Farrán, and María Luisa Martín
Weather Clim. Dynam., 3, 1021–1036, https://doi.org/10.5194/wcd-3-1021-2022, https://doi.org/10.5194/wcd-3-1021-2022, 2022
Short summary
Short summary
Supercells are among the most complex and dangerous severe convective storms due to their associated phenomena (lightning, strong winds, large hail, flash floods, or tornadoes). In this survey we study the supercell synoptic configurations and convective environments in Spain using the atmospheric reanalysis ERA5. Supercells are grouped into hail (greater than 5 cm) and non-hail events in order to compare and analyze the two events. The results reveal statistically significant differences.
Felipe Lobos-Roco, Oscar Hartogensis, Francisco Suárez, Ariadna Huerta-Viso, Imme Benedict, Alberto de la Fuente, and Jordi Vilà-Guerau de Arellano
Hydrol. Earth Syst. Sci., 26, 3709–3729, https://doi.org/10.5194/hess-26-3709-2022, https://doi.org/10.5194/hess-26-3709-2022, 2022
Short summary
Short summary
This research brings a multi-scale temporal analysis of evaporation in a saline lake of the Atacama Desert. Our findings reveal that evaporation is controlled differently depending on the timescale. Evaporation is controlled sub-diurnally by wind speed, regulated seasonally by radiation and modulated interannually by ENSO. Our research extends our understanding of evaporation, contributing to improving the climate change assessment and efficiency of water management in arid regions.
Ruben B. Schulte, Margreet C. van Zanten, Bart J. H. van Stratum, and Jordi Vilà-Guerau de Arellano
Atmos. Chem. Phys., 22, 8241–8257, https://doi.org/10.5194/acp-22-8241-2022, https://doi.org/10.5194/acp-22-8241-2022, 2022
Short summary
Short summary
We present a fine-scale simulation framework, utilizing large-eddy simulations, to assess NH3 measurements influenced by boundary-layer dynamics and turbulent dispersion of a nearby emission source. The minimum required distance from an emission source differs for concentration and flux measurements, from 0.5–3.0 km and 0.75–4.5 km, respectively. The simulation framework presented here proves to be a powerful and versatile tool for future NH3 research at high spatio-temporal resolutions.
Carlos Román-Cascón, Marie Lothon, Fabienne Lohou, Oscar Hartogensis, Jordi Vila-Guerau de Arellano, David Pino, Carlos Yagüe, and Eric R. Pardyjak
Geosci. Model Dev., 14, 3939–3967, https://doi.org/10.5194/gmd-14-3939-2021, https://doi.org/10.5194/gmd-14-3939-2021, 2021
Short summary
Short summary
The type of vegetation (or land cover) and its status influence the heat and water transfers between the surface and the air, affecting the processes that develop in the atmosphere at different (but connected) spatiotemporal scales. In this work, we investigate how these transfers are affected by the way the surface is represented in a widely used weather model. The results encourage including realistic high-resolution and updated land cover databases in models to improve their predictions.
Felipe Lobos-Roco, Oscar Hartogensis, Jordi Vilà-Guerau de Arellano, Alberto de la Fuente, Ricardo Muñoz, José Rutllant, and Francisco Suárez
Atmos. Chem. Phys., 21, 9125–9150, https://doi.org/10.5194/acp-21-9125-2021, https://doi.org/10.5194/acp-21-9125-2021, 2021
Short summary
Short summary
We investigate the influence of regional atmospheric circulation on the evaporation of a saline lake in the Altiplano region of the Atacama Desert through a field experiment and regional modeling. Our results show that evaporation is controlled by two regimes: (1) in the morning by local conditions with low evaporation rates and low wind speed and (2) in the afternoon with high evaporation rates and high wind speed. Afternoon winds are connected to the regional Pacific Ocean–Andes flow.
Martin Dörenkämper, Bjarke T. Olsen, Björn Witha, Andrea N. Hahmann, Neil N. Davis, Jordi Barcons, Yasemin Ezber, Elena García-Bustamante, J. Fidel González-Rouco, Jorge Navarro, Mariano Sastre-Marugán, Tija Sīle, Wilke Trei, Mark Žagar, Jake Badger, Julia Gottschall, Javier Sanz Rodrigo, and Jakob Mann
Geosci. Model Dev., 13, 5079–5102, https://doi.org/10.5194/gmd-13-5079-2020, https://doi.org/10.5194/gmd-13-5079-2020, 2020
Short summary
Short summary
This is the second of two papers that document the creation of the New European Wind Atlas (NEWA). The paper includes a detailed description of the technical and practical aspects that went into running the mesoscale simulations and the microscale downscaling for generating the climatology. A comprehensive evaluation of each component of the NEWA model chain is presented using observations from a large set of tall masts located all over Europe.
Nikolaos Schetakis, Rodrigo Crespo, José Luis Vázquez-Poletti, Mariano Sastre, Luis Vázquez, and Alessio Di Iorio
Geosci. Instrum. Method. Data Syst., 9, 407–415, https://doi.org/10.5194/gi-9-407-2020, https://doi.org/10.5194/gi-9-407-2020, 2020
Short summary
Short summary
In this paper, we present a compilation of the different radiation transport codes for the Martian surface that are currently used by various space agencies and institutions. In addition, as the execution of the tasks necessary to process all of these radiation data requires a high computational processing capacity, we link it to cloud computing, which is found to be an appropriate tool regarding the required resources.
Jordi Vilà-Guerau de Arellano, Patrizia Ney, Oscar Hartogensis, Hugo de Boer, Kevin van Diepen, Dzhaner Emin, Geiske de Groot, Anne Klosterhalfen, Matthias Langensiepen, Maria Matveeva, Gabriela Miranda-García, Arnold F. Moene, Uwe Rascher, Thomas Röckmann, Getachew Adnew, Nicolas Brüggemann, Youri Rothfuss, and Alexander Graf
Biogeosciences, 17, 4375–4404, https://doi.org/10.5194/bg-17-4375-2020, https://doi.org/10.5194/bg-17-4375-2020, 2020
Short summary
Short summary
The CloudRoots field experiment has obtained an open comprehensive observational data set that includes soil, plant, and atmospheric variables to investigate the interactions between a heterogeneous land surface and its overlying atmospheric boundary layer, including the rapid perturbations of clouds in evapotranspiration. Our findings demonstrate that in order to understand and represent diurnal variability, we need to measure and model processes from the leaf to the landscape scales.
Xabier Pedruzo-Bagazgoitia, Stephan R. de Roode, Bianca Adler, Karmen Babić, Cheikh Dione, Norbert Kalthoff, Fabienne Lohou, Marie Lothon, and Jordi Vilà-Guerau de Arellano
Atmos. Chem. Phys., 20, 2735–2754, https://doi.org/10.5194/acp-20-2735-2020, https://doi.org/10.5194/acp-20-2735-2020, 2020
Short summary
Short summary
Using a high-resolution model we simulate the transition from night to day clouds on southern West Africa using observations from the DACCIWA project. We find that the radiative effects of clouds help mantain a thick cloud layer in the night, while the mixing of cloud air with air above during the day, aided by moisture and heat fluxes at the surface, thins this layer and promotes its transition to other clouds. The effect of changing wind with height accelerates the transition.
Marco de Bruine, Maarten Krol, Jordi Vilà-Guerau de Arellano, and Thomas Röckmann
Geosci. Model Dev., 12, 5177–5196, https://doi.org/10.5194/gmd-12-5177-2019, https://doi.org/10.5194/gmd-12-5177-2019, 2019
Short summary
Short summary
An aerosol scheme with multiple aerosol species is introduced in the Dutch Atmospheric Large-Eddy Simulation model (DALES) and focused to simulate the feedback of aerosol–cloud interaction (ACI) on the aerosol population. Cloud aerosol processing is found to be sensitive to the numerical method, while removal by precipitation is more stable. How ACI increases or decreases the mean aerosol size depends on the balance between the evaporation of clouds/rain and ultimate removal by precipitation.
Pierre Gentine, Adam Massmann, Benjamin R. Lintner, Sayed Hamed Alemohammad, Rong Fu, Julia K. Green, Daniel Kennedy, and Jordi Vilà-Guerau de Arellano
Hydrol. Earth Syst. Sci., 23, 4171–4197, https://doi.org/10.5194/hess-23-4171-2019, https://doi.org/10.5194/hess-23-4171-2019, 2019
Short summary
Short summary
Land–atmosphere interactions are key for the exchange of water, energy, and carbon dioxide, especially in the tropics. We here review some of the recent findings on land–atmosphere interactions in the tropics and where we see potential challenges and paths forward.
Hendrik Wouters, Irina Y. Petrova, Chiel C. van Heerwaarden, Jordi Vilà-Guerau de Arellano, Adriaan J. Teuling, Vicky Meulenberg, Joseph A. Santanello, and Diego G. Miralles
Geosci. Model Dev., 12, 2139–2153, https://doi.org/10.5194/gmd-12-2139-2019, https://doi.org/10.5194/gmd-12-2139-2019, 2019
Short summary
Short summary
The free software CLASS4GL (http://class4gl.eu) is designed to investigate the dynamic atmospheric boundary layer (ABL) with weather balloons. It mines observational data from global radio soundings, satellite and reanalysis data from the last 40 years to constrain and initialize an ABL model and automizes multiple experiments in parallel. CLASS4GL aims at fostering a better understanding of land–atmosphere feedbacks and the drivers of extreme weather.
Juhi Nagori, Ruud H. H. Janssen, Juliane L. Fry, Maarten Krol, Jose L. Jimenez, Weiwei Hu, and Jordi Vilà-Guerau de Arellano
Atmos. Chem. Phys., 19, 701–729, https://doi.org/10.5194/acp-19-701-2019, https://doi.org/10.5194/acp-19-701-2019, 2019
Short summary
Short summary
Secondary organic aerosol (SOA) is produced through a complex interaction of sunlight, volatile organic compounds emitted from trees, anthropogenic emissions, and atmospheric chemistry. We are able to successfully model the formation and diurnal evolution of SOA using a model that takes into consideration the surface and boundary layer dynamics (1–2 km from the surface) and photochemistry above the southeastern US with data collected during the SOAS campaign to constrain the model.
Metodija M. Shapkalijevski, Huug G. Ouwersloot, Arnold F. Moene, and Jordi Vilà-Guerau de Arrellano
Atmos. Chem. Phys., 17, 1623–1640, https://doi.org/10.5194/acp-17-1623-2017, https://doi.org/10.5194/acp-17-1623-2017, 2017
Manuel Tijera, Gregorio Maqueda, and Carlos Yagüe
Nonlin. Processes Geophys., 23, 407–417, https://doi.org/10.5194/npg-23-407-2016, https://doi.org/10.5194/npg-23-407-2016, 2016
Short summary
Short summary
This work investigates the possible correlations between the integral scale of the turbulent stratified flows in the atmospheric boundary layer and parameters characterizing topological features of the wind velocity field, such as fractal dimension and its stability properties, studied through the bulk Richardson number. Fractal dimension and the integral scale of the horizontal (u') and vertical (w') velocity fluctuations have been calculated using the mean wind direction as a framework.
Joan Cuxart, Burkhard Wrenger, Daniel Martínez-Villagrasa, Joachim Reuder, Marius O. Jonassen, Maria A. Jiménez, Marie Lothon, Fabienne Lohou, Oscar Hartogensis, Jens Dünnermann, Laura Conangla, and Anirban Garai
Atmos. Chem. Phys., 16, 9489–9504, https://doi.org/10.5194/acp-16-9489-2016, https://doi.org/10.5194/acp-16-9489-2016, 2016
Short summary
Short summary
Estimations of the effect of thermal advection in the surface energy budget are provided. Data from the experimental campaign BLLAST, held in Southern France in summer 2011, are used, including airborne data by drones and surface-based instrumentation. Model data outputs and satellite information are also inspected. Surface heterogeneities of the order of the kilometer or larger seem to have little effect on the budget, whereas hectometer-scale structures may contribute significantly to it.
Astrid Lampert, Falk Pätzold, Maria Antonia Jiménez, Lennart Lobitz, Sabrina Martin, Gerald Lohmann, Guylaine Canut, Dominique Legain, Jens Bange, Dani Martínez-Villagrasa, and Joan Cuxart
Atmos. Chem. Phys., 16, 8009–8021, https://doi.org/10.5194/acp-16-8009-2016, https://doi.org/10.5194/acp-16-8009-2016, 2016
Short summary
Short summary
For a large field experiment in summer 2011 in southern France (BLLAST campaign), the development of turbulence in the atmosphere was analysed during the afternoon and evening. Besides ground-based remote sensing and in situ observations, turbulence parameters were measured with an unmanned aerial vehicle and analysed by numerical simulation. Turbulence decreased during the afternoon, but increased after sunset due to local wind systems. Turbulent eddies lost symmetry during the transition.
Luping Su, Edward G. Patton, Jordi Vilà-Guerau de Arellano, Alex B. Guenther, Lisa Kaser, Bin Yuan, Fulizi Xiong, Paul B. Shepson, Li Zhang, David O. Miller, William H. Brune, Karsten Baumann, Eric Edgerton, Andrew Weinheimer, Pawel K. Misztal, Jeong-Hoo Park, Allen H. Goldstein, Kate M. Skog, Frank N. Keutsch, and John E. Mak
Atmos. Chem. Phys., 16, 7725–7741, https://doi.org/10.5194/acp-16-7725-2016, https://doi.org/10.5194/acp-16-7725-2016, 2016
C. Darbieu, F. Lohou, M. Lothon, J. Vilà-Guerau de Arellano, F. Couvreux, P. Durand, D. Pino, E. G. Patton, E. Nilsson, E. Blay-Carreras, and B. Gioli
Atmos. Chem. Phys., 15, 10071–10086, https://doi.org/10.5194/acp-15-10071-2015, https://doi.org/10.5194/acp-15-10071-2015, 2015
Short summary
Short summary
A case study of the BLLAST experiment is considered to explore the decay of turbulence that occurs in the convective boundary layer over land during the afternoon. Based on observations and on a large-eddy simulation, the analysis reveals two phases in the afternoon: a first quasi-stationary phase when the turbulent kinetic energy slowly decays without significant change in the turbulence structure and a second phase of more rapid decay with a change in spectral turbulence characteristics.
C. Román-Cascón, C. Yagüe, L. Mahrt, M. Sastre, G.-J. Steeneveld, E. Pardyjak, A. van de Boer, and O. Hartogensis
Atmos. Chem. Phys., 15, 9031–9047, https://doi.org/10.5194/acp-15-9031-2015, https://doi.org/10.5194/acp-15-9031-2015, 2015
Short summary
Short summary
Stable-boundary-layer processes have been analysed using BLLAST data. Shallow drainage flows were formed at some locations after the near calm stage of the late afternoon. This stage ended with the arrival of a deeper wind associated with the mountain-plain circulation. At the same time, gravity waves were detected with an array of microbarometers. The interaction of these processes with turbulence was studied through multi-resolution flux decomposition at different sites and heights.
H. P. Pietersen, J. Vilà-Guerau de Arellano, P. Augustin, A. van de Boer, O. de Coster, H. Delbarre, P. Durand, M. Fourmentin, B. Gioli, O. Hartogensis, F. Lohou, M. Lothon, H. G. Ouwersloot, D. Pino, and J. Reuder
Atmos. Chem. Phys., 15, 4241–4257, https://doi.org/10.5194/acp-15-4241-2015, https://doi.org/10.5194/acp-15-4241-2015, 2015
M. Combe, J. Vilà-Guerau de Arellano, H. G. Ouwersloot, C. M. J. Jacobs, and W. Peters
Biogeosciences, 12, 103–123, https://doi.org/10.5194/bg-12-103-2015, https://doi.org/10.5194/bg-12-103-2015, 2015
Short summary
Short summary
This study investigates the interactions among the carbon, water and heat cycles above a maize field at the diurnal scale. We couple two land-surface schemes, corresponding to two different modelling approaches, to the same atmospheric boundary-layer (ABL) model. We find the simpler meteorological approach best reproduces the surface and upper-air observations. Finally, we show that the interaction of subsidence with ABL dynamics is key to explain the daytime atmospheric CO2 budget.
M. Lothon, F. Lohou, D. Pino, F. Couvreux, E. R. Pardyjak, J. Reuder, J. Vilà-Guerau de Arellano, P Durand, O. Hartogensis, D. Legain, P. Augustin, B. Gioli, D. H. Lenschow, I. Faloona, C. Yagüe, D. C. Alexander, W. M. Angevine, E Bargain, J. Barrié, E. Bazile, Y. Bezombes, E. Blay-Carreras, A. van de Boer, J. L. Boichard, A. Bourdon, A. Butet, B. Campistron, O. de Coster, J. Cuxart, A. Dabas, C. Darbieu, K. Deboudt, H. Delbarre, S. Derrien, P. Flament, M. Fourmentin, A. Garai, F. Gibert, A. Graf, J. Groebner, F. Guichard, M. A. Jiménez, M. Jonassen, A. van den Kroonenberg, V. Magliulo, S. Martin, D. Martinez, L. Mastrorillo, A. F. Moene, F. Molinos, E. Moulin, H. P. Pietersen, B. Piguet, E. Pique, C. Román-Cascón, C. Rufin-Soler, F. Saïd, M. Sastre-Marugán, Y. Seity, G. J. Steeneveld, P. Toscano, O. Traullé, D. Tzanos, S. Wacker, N. Wildmann, and A. Zaldei
Atmos. Chem. Phys., 14, 10931–10960, https://doi.org/10.5194/acp-14-10931-2014, https://doi.org/10.5194/acp-14-10931-2014, 2014
J. A. Adame, M. Martínez, M. Sorribas, P. J. Hidalgo, H. Harder, J.-M. Diesch, F. Drewnick, W. Song, J. Williams, V. Sinha, M. A. Hernández-Ceballos, J. Vilà-Guerau de Arellano, R. Sander, Z. Hosaynali-Beygi, H. Fischer, J. Lelieveld, and B. De la Morena
Atmos. Chem. Phys., 14, 2325–2342, https://doi.org/10.5194/acp-14-2325-2014, https://doi.org/10.5194/acp-14-2325-2014, 2014
Related subject area
Subject: Dynamics | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Identification and characterization of foehn events in Beijing and their impact on air-pollution episodes
Evidence of Tropospheric Uplift into the Stratosphere via the Tropical Western Pacific Cold Trap
Impact of Convectively Coupled Tropical Waves on the composition and vertical structure of the atmosphere above Cabo Verde in September 2021 during the CADDIWA campaign
Impact of boundary layer stability on urban park cooling effect intensity
Investigation of non-equilibrium turbulence decay in the atmospheric boundary layer using Doppler lidar measurements
Measurement report: The promotion of the low-level jet and thermal effects on the development of the deep convective boundary layer at the southern edge of the Taklimakan Desert
Estimating scalar turbulent fluxes with slow-response sensors in the stable atmospheric boundary layer
Overview: quasi-Lagrangian observations of Arctic air mass transformations – introduction and initial results of the HALO–(𝒜 𝒞)3 aircraft campaign
Contrasting extremely warm and long-lasting cold air anomalies in the North Atlantic sector of the Arctic during the HALO-(𝒜 𝒞)3 campaign
Air–sea interactions in stable atmospheric conditions: lessons from the desert semi-enclosed Gulf of Eilat (Aqaba)
An overview of the vertical structure of the atmospheric boundary layer in the central Arctic during MOSAiC
Evaluation of methods to determine the surface mixing layer height of the atmospheric boundary layer in the central Arctic during polar night and transition to polar day in cloudless and cloudy conditions
The role of a low-level jet for stirring the stable atmospheric surface layer in the Arctic
Detection of dilution due to turbulent mixing vs. precipitation scavenging effects on biomass burning aerosol concentrations using stable water isotope ratios during ORACLES
Modulation of the intraseasonal variability in early summer precipitation in eastern China by the Quasi-Biennial Oscillation and the Madden–Julian Oscillation
Thermodynamic and kinematic drivers of atmospheric boundary layer stability in the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC)
Occurrence frequency of subcritical Richardson numbers assessed by global high-resolution radiosonde and ERA5 reanalysis
The characteristics of atmospheric boundary layer height over the Arctic Ocean during MOSAiC
Turbulent structure of the Arctic boundary layer in early summer driven by stability, wind shear and cloud-top radiative cooling: ACLOUD airborne observations
Dependency of vertical velocity variance on meteorological conditions in the convective boundary layer
Triggering effects of large topography and boundary layer turbulence on convection over the Tibetan Plateau
A change in the relation between the Subtropical Indian Ocean Dipole and the South Atlantic Ocean Dipole indices in the past four decades
Characterising the dynamic movement of thunderstorms using very low- and low-frequency (VLF/LF) total lightning data over the Pearl River Delta region
Evolution of turbulent kinetic energy during the entire sandstorm process
Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North Atlantic
The effect of ice supersaturation and thin cirrus on lapse rates in the upper troposphere
Momentum fluxes from airborne wind measurements in three cumulus cases over land
Orographically induced spontaneous imbalance within the jet causing a large-scale gravity wave event
Exploring the elevated water vapor signal associated with the free tropospheric biomass burning plume over the southeast Atlantic Ocean
Opinion: Gigacity – a source of problems or the new way to sustainable development
The thermodynamic structures of the planetary boundary layer dominated by synoptic circulations and the regular effect on air pollution in Beijing
Turbulent and boundary layer characteristics during VOCALS-REx
A foehn-induced haze front in Beijing: observations and implications
Airborne measurements and large-eddy simulations of small-scale gravity waves at the tropopause inversion layer over Scandinavia
Observational analysis of the daily cycle of the planetary boundary layer in the central Amazon during a non-El Niño year and El Niño year (GoAmazon project 2014/5)
Planetary boundary layer evolution over the Amazon rainforest in episodes of deep moist convection at the Amazon Tall Tower Observatory
Dominant patterns of summer ozone pollution in eastern China and associated atmospheric circulations
What controls the formation of nocturnal low-level stratus clouds over southern West Africa during the monsoon season?
Recent trends in climate variability at the local scale using 40 years of observations: the case of the Paris region of France
Nocturnal boundary layer turbulence regimes analysis during the BLLAST campaign
Low-level stratiform clouds and dynamical features observed within the southern West African monsoon
Residual layer ozone, mixing, and the nocturnal jet in California's San Joaquin Valley
On the fine vertical structure of the low troposphere over the coastal margins of East Antarctica
Spatial and temporal variability of turbulence dissipation rate in complex terrain
Characterizing wind gusts in complex terrain
Long-term trends of instability and associated parameters over the Indian region obtained using a radiosonde network
Implication of tropical lower stratospheric cooling in recent trends in tropical circulation and deep convective activity
The observed diurnal cycle of low-level stratus clouds over southern West Africa: a case study
Nocturnal low-level clouds in the atmospheric boundary layer over southern West Africa: an observation-based analysis of conditions and processes
Characteristics and evolution of diurnal foehn events in the Dead Sea valley
Ju Li, Jingjiang Zhang, Mengxin Bai, Jie Su, Qingchun Li, and Xingcan Jia
EGUsphere, https://doi.org/10.5194/egusphere-2024-2684, https://doi.org/10.5194/egusphere-2024-2684, 2025
Short summary
Short summary
This research examines foehn events in Beijing using weather station data from 2015 to 2020. We found an average of 56.5 foehn days annually, primarily in winter. These winds can raise temperatures significantly and are associated with air-pollution levels. Strong foehn winds tend to reduce pollution, while weaker winds may increase it. Our study highlights the impact of foehn events on air quality, providing valuable insights for urban planning and environmental management.
Xiaoyu Sun, Katrin Müller, Mathias Palm, Christoph Ritter, Denghui Ji, Tim Balthasar Röpke, and Justus Notholt
EGUsphere, https://doi.org/10.5194/egusphere-2024-3981, https://doi.org/10.5194/egusphere-2024-3981, 2025
Short summary
Short summary
We studied how air moves from the lower atmosphere to the stratosphere over the Tropical Western Pacific, a region with very cold temperatures high up. By using ground-based observations and tracking air movement, we found that during winter, the formation of thin cloud allow air to rise, while in summer, most of the air sinks down. This process changes the water vapor amount in the stratosphere, which influences the greenhouse effect and plays an important role in climate change.
Tanguy Jonville, Maurus Borne, Cyrille Flamant, Juan Cuesta, Olivier Bock, Pierre Bosser, Christophe Lavaysse, Andreas Fink, and Peter Knippertz
EGUsphere, https://doi.org/10.5194/egusphere-2024-3606, https://doi.org/10.5194/egusphere-2024-3606, 2025
Short summary
Short summary
Tropical waves structure the atmosphere. Four types of tropical waves (ER, Kelvin, MRG-TD1, and MRG-TD2) are studied using filters, satellite measurements, and in situ data from the Clouds-Atmosphere Dynamics-Dust Interaction in West Africa (CADDIWA) campaign held in September 2021 in Cabo Verde. ER waves impact temperature and humidity above 2500 m, MRG-TD1 around 3500 m, and MRG-TD2 around 2000 m. Interactions between these waves favor tropical cyclone formation.
Martial Haeffelin, Jean-François Ribaud, Jonnathan Céspedes, Jean-Charles Dupont, Aude Lemonsu, Valéry Masson, Tim Nagel, and Simone Kotthaus
Atmos. Chem. Phys., 24, 14101–14122, https://doi.org/10.5194/acp-24-14101-2024, https://doi.org/10.5194/acp-24-14101-2024, 2024
Short summary
Short summary
This study highlights how the state of the urban atmospheric boundary layer impacts urban park cooling effect intensity at night. Under summertime heat wave conditions, the urban atmosphere becomes stable at night, which inhibits turbulent motions. Under those specific conditions, urban parks and woods cool much more efficiently than the surrounding built-up neighbourhoods in the evening and through the night, providing cooler air temperatures by 4 to 6° C depending on park size.
Maciej Karasewicz, Marta Wacławczyk, Pablo Ortiz-Amezcua, Łucja Janicka, Patryk Poczta, Camilla Kassar Borges, and Iwona S. Stachlewska
Atmos. Chem. Phys., 24, 13231–13251, https://doi.org/10.5194/acp-24-13231-2024, https://doi.org/10.5194/acp-24-13231-2024, 2024
Short summary
Short summary
This work concerns analysis of turbulence in the atmospheric boundary layer shortly before sunset. Based on a large set of measurements at a rural and an urban site, we analyze how turbulence properties change in time during rapid decay of convection. We explain the observations using recent theories of non-equilibrium turbulence. The presence of non-equilibrium suggests that classical parametrization schemes fail to predict turbulence statistics shortly before sunset.
Lian Su, Chunsong Lu, Jinlong Yuan, Xiaofei Wang, Qing He, and Haiyun Xia
Atmos. Chem. Phys., 24, 10947–10963, https://doi.org/10.5194/acp-24-10947-2024, https://doi.org/10.5194/acp-24-10947-2024, 2024
Short summary
Short summary
The cold downhill airflow of the Tibetan Plateau leading to the low-level jet weakens the height and intensity of the inversion layer, which reduces the energy demand for the broken inversion layer. The low-level jet causes dust aerosols to accumulate near the ground. The material conditions for the development of the desert atmospheric boundary layer can be quickly transformed into thermal conditions.
Mohammad Allouche, Vladislav I. Sevostianov, Einara Zahn, Mark A. Zondlo, Nelson Luís Dias, Gabriel G. Katul, Jose D. Fuentes, and Elie Bou-Zeid
Atmos. Chem. Phys., 24, 9697–9711, https://doi.org/10.5194/acp-24-9697-2024, https://doi.org/10.5194/acp-24-9697-2024, 2024
Short summary
Short summary
The significance of surface–atmosphere exchanges of aerosol species to atmospheric composition is underscored by their rising concentrations that are modulating the Earth's climate and having detrimental consequences for human health and the environment. Estimating these exchanges, using field measurements, and offering alternative models are the aims here. Limitations in measuring some species misrepresent their actual exchanges, so our proposed models serve to better quantify them.
Manfred Wendisch, Susanne Crewell, André Ehrlich, Andreas Herber, Benjamin Kirbus, Christof Lüpkes, Mario Mech, Steven J. Abel, Elisa F. Akansu, Felix Ament, Clémantyne Aubry, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Marlen Brückner, Hans-Christian Clemen, Sandro Dahlke, Georgios Dekoutsidis, Julien Delanoë, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Irina V. Gorodetskaya, Sarah Grawe, Silke Groß, Jörg Hartmann, Silvia Henning, Lutz Hirsch, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsofia Jurányi, Michail Karalis, Mona Kellermann, Marcus Klingebiel, Michael Lonardi, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Marion Maturilli, Bernhard Mayer, Johanna Mayer, Stephan Mertes, Janosch Michaelis, Michel Michalkov, Guillaume Mioche, Manuel Moser, Hanno Müller, Roel Neggers, Davide Ori, Daria Paul, Fiona M. Paulus, Christian Pilz, Felix Pithan, Mira Pöhlker, Veronika Pörtge, Maximilian Ringel, Nils Risse, Gregory C. Roberts, Sophie Rosenburg, Johannes Röttenbacher, Janna Rückert, Michael Schäfer, Jonas Schaefer, Vera Schemann, Imke Schirmacher, Jörg Schmidt, Sebastian Schmidt, Johannes Schneider, Sabrina Schnitt, Anja Schwarz, Holger Siebert, Harald Sodemann, Tim Sperzel, Gunnar Spreen, Bjorn Stevens, Frank Stratmann, Gunilla Svensson, Christian Tatzelt, Thomas Tuch, Timo Vihma, Christiane Voigt, Lea Volkmer, Andreas Walbröl, Anna Weber, Birgit Wehner, Bruno Wetzel, Martin Wirth, and Tobias Zinner
Atmos. Chem. Phys., 24, 8865–8892, https://doi.org/10.5194/acp-24-8865-2024, https://doi.org/10.5194/acp-24-8865-2024, 2024
Short summary
Short summary
The Arctic is warming faster than the rest of the globe. Warm-air intrusions (WAIs) into the Arctic may play an important role in explaining this phenomenon. Cold-air outbreaks (CAOs) out of the Arctic may link the Arctic climate changes to mid-latitude weather. In our article, we describe how to observe air mass transformations during CAOs and WAIs using three research aircraft instrumented with state-of-the-art remote-sensing and in situ measurement devices.
Andreas Walbröl, Janosch Michaelis, Sebastian Becker, Henning Dorff, Kerstin Ebell, Irina Gorodetskaya, Bernd Heinold, Benjamin Kirbus, Melanie Lauer, Nina Maherndl, Marion Maturilli, Johanna Mayer, Hanno Müller, Roel A. J. Neggers, Fiona M. Paulus, Johannes Röttenbacher, Janna E. Rückert, Imke Schirmacher, Nils Slättberg, André Ehrlich, Manfred Wendisch, and Susanne Crewell
Atmos. Chem. Phys., 24, 8007–8029, https://doi.org/10.5194/acp-24-8007-2024, https://doi.org/10.5194/acp-24-8007-2024, 2024
Short summary
Short summary
To support the interpretation of the data collected during the HALO-(AC)3 campaign, which took place in the North Atlantic sector of the Arctic from 7 March to 12 April 2022, we analyze how unusual the weather and sea ice conditions were with respect to the long-term climatology. From observations and ERA5 reanalysis, we found record-breaking warm air intrusions and a large variety of marine cold air outbreaks. Sea ice concentration was mostly within the climatological interquartile range.
Shai Abir, Hamish A. McGowan, Yonatan Shaked, Hezi Gildor, Efrat Morin, and Nadav G. Lensky
Atmos. Chem. Phys., 24, 6177–6195, https://doi.org/10.5194/acp-24-6177-2024, https://doi.org/10.5194/acp-24-6177-2024, 2024
Short summary
Short summary
Understanding air–sea heat exchange is vital for studying ocean dynamics. Eddy covariance measurements over the Gulf of Eilat revealed a 3.22 m yr-1 evaporation rate, which is inconsistent with bulk formulae estimations in stable atmospheric conditions, requiring bulk formulae to be revisited in these environments. The surface fluxes have a net cooling effect on the gulf water on an annual mean (-79 W m-2), balanced by a strong exchange flux between the Red Sea and the Gulf of Eilat.
Gina C. Jozef, John J. Cassano, Sandro Dahlke, Mckenzie Dice, Christopher J. Cox, and Gijs de Boer
Atmos. Chem. Phys., 24, 1429–1450, https://doi.org/10.5194/acp-24-1429-2024, https://doi.org/10.5194/acp-24-1429-2024, 2024
Short summary
Short summary
Observations collected during MOSAiC were used to identify the range in vertical structure and stability of the central Arctic lower atmosphere through a self-organizing map analysis. Characteristics of wind features (such as low-level jets) and atmospheric moisture features (such as clouds) were analyzed in the context of the varying vertical structure and stability. Thus, the results of this paper give an overview of the thermodynamic and kinematic features of the central Arctic atmosphere.
Elisa F. Akansu, Sandro Dahlke, Holger Siebert, and Manfred Wendisch
Atmos. Chem. Phys., 23, 15473–15489, https://doi.org/10.5194/acp-23-15473-2023, https://doi.org/10.5194/acp-23-15473-2023, 2023
Short summary
Short summary
The height of the mixing layer is an important measure of the surface-level distribution of energy or other substances. The experimental determination of this height is associated with large uncertainties, particularly under stable conditions that we often find during the polar night or in the presence of clouds. We present a reference method using turbulence measurements on a tethered balloon, which allows us to evaluate approaches based on radiosondes or surface observations.
Ulrike Egerer, Holger Siebert, Olaf Hellmuth, and Lise Lotte Sørensen
Atmos. Chem. Phys., 23, 15365–15373, https://doi.org/10.5194/acp-23-15365-2023, https://doi.org/10.5194/acp-23-15365-2023, 2023
Short summary
Short summary
Low-level jets (LLJs) are strong winds near the surface and occur frequently in the Arctic in stable conditions. Using tethered-balloon profile measurements in Greenland, we analyze a multi-hour period with an LLJ that later weakens and finally collapses. Increased shear-induced turbulence at the LLJ bounds mostly does not reach the ground until the LLJ collapses. Our findings support the hypothesis that a passive tracer can be advected with an LLJ and mixed down when the LLJ collapses.
Dean Henze, David Noone, and Darin Toohey
Atmos. Chem. Phys., 23, 15269–15288, https://doi.org/10.5194/acp-23-15269-2023, https://doi.org/10.5194/acp-23-15269-2023, 2023
Short summary
Short summary
The interaction between biomass burning aerosols and clouds remains challenging to accurately determine from observations. This is in part because of difficulties distinguishing aerosol differences due to precipitation versus dilution processes from the observations. This study addresses the challenge by utilizing atmospheric heavy water isotope ratios to constrain mixing versus precipitation processes during a field campaign (ORACLES) and in turn explain observed aerosol concentrations.
Zefan Ju, Jian Rao, Yue Wang, Junfeng Yang, and Qian Lu
Atmos. Chem. Phys., 23, 14903–14918, https://doi.org/10.5194/acp-23-14903-2023, https://doi.org/10.5194/acp-23-14903-2023, 2023
Short summary
Short summary
In the paper, we explored the impact of the Madden–Julian Oscillation (MJO) and the Quasi-Biennial Oscillation (QBO) on East China summer rainfall variability. It is novel to find that the combined impact of MJO and QBO is not maximized when the QBO and MJO are in phase to enhance (or suppress) the tropical convection.
Gina C. Jozef, John J. Cassano, Sandro Dahlke, Mckenzie Dice, Christopher J. Cox, and Gijs de Boer
Atmos. Chem. Phys., 23, 13087–13106, https://doi.org/10.5194/acp-23-13087-2023, https://doi.org/10.5194/acp-23-13087-2023, 2023
Short summary
Short summary
Observations from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) were used to determine the frequency of occurrence of various central Arctic lower atmospheric stability regimes and how the stability regimes transition between each other. Wind and radiation observations were analyzed in the context of stability regime and season to reveal the relationships between Arctic atmospheric stability and mechanically and radiatively driven turbulent forcings.
Jia Shao, Jian Zhang, Wuke Wang, Shaodong Zhang, Tao Yu, and Wenjun Dong
Atmos. Chem. Phys., 23, 12589–12607, https://doi.org/10.5194/acp-23-12589-2023, https://doi.org/10.5194/acp-23-12589-2023, 2023
Short summary
Short summary
Kelvin–Helmholtz instability (KHI) is indicated by the critical value of the Richardson (Ri) number, which is usually predicted to be 1/4. Compared to high-resolution radiosondes, the threshold value of Ri could be approximated as 1 rather than 1/4 when using ERA5-based Ri as a proxy for KHI. The occurrence frequency of subcritical Ri exhibits significant seasonal cycles over all climate zones and is closely associated with gravity waves and background flows.
Shijie Peng, Qinghua Yang, Matthew D. Shupe, Xingya Xi, Bo Han, Dake Chen, Sandro Dahlke, and Changwei Liu
Atmos. Chem. Phys., 23, 8683–8703, https://doi.org/10.5194/acp-23-8683-2023, https://doi.org/10.5194/acp-23-8683-2023, 2023
Short summary
Short summary
Due to a lack of observations, the structure of the Arctic atmospheric boundary layer (ABL) remains to be further explored. By analyzing a year-round radiosonde dataset collected over the Arctic sea-ice surface, we found the annual cycle of the ABL height (ABLH) is primarily controlled by the evolution of ABL thermal structure, and the surface conditions also show a high correlation with ABLH variation. In addition, the Arctic ABLH is found to be decreased in summer compared with 20 years ago.
Dmitry G. Chechin, Christof Lüpkes, Jörg Hartmann, André Ehrlich, and Manfred Wendisch
Atmos. Chem. Phys., 23, 4685–4707, https://doi.org/10.5194/acp-23-4685-2023, https://doi.org/10.5194/acp-23-4685-2023, 2023
Short summary
Short summary
Clouds represent a very important component of the Arctic climate system, as they strongly reduce the amount of heat lost to space from the sea ice surface. Properties of clouds, as well as their persistence, strongly depend on the complex interaction of such small-scale properties as phase transitions, radiative transfer and turbulence. In this study we use airborne observations to learn more about the effect of clouds and radiative cooling on turbulence in comparison with other factors.
Noviana Dewani, Mirjana Sakradzija, Linda Schlemmer, Ronny Leinweber, and Juerg Schmidli
Atmos. Chem. Phys., 23, 4045–4058, https://doi.org/10.5194/acp-23-4045-2023, https://doi.org/10.5194/acp-23-4045-2023, 2023
Short summary
Short summary
A high daily variability of the normalized vertical velocity variance profiles in the convective boundary layer is observed using Doppler lidar data during the FESSTVaL campaign 2020–2021. The dependency of the normalized vertical velocity variance on several meteorological parameters explains that the moisture processes in the boundary layer contribute to the remaining variability. The finding suggests that a new vertical velocity scale that takes moist processes into account has to be defined.
Xiangde Xu, Yi Tang, Yinjun Wang, Hongshen Zhang, Ruixia Liu, and Mingyu Zhou
Atmos. Chem. Phys., 23, 3299–3309, https://doi.org/10.5194/acp-23-3299-2023, https://doi.org/10.5194/acp-23-3299-2023, 2023
Short summary
Short summary
The vertical motion over the Tibetan Plateau (TP) is associated with the anomalous convective activities. The diurnal variations and formation mechanisms of low clouds over the TP, Rocky Mountains and low-elevation regions are analyzed. We further discuss whether there exists a
high-efficiencytriggering mechanism for convection over the TP and whether there is an association among low air density and strong turbulence and ubiquitous popcorn-like cumulus clouds.
Lejiang Yu, Shiyuan Zhong, Timo Vihma, Cuijuan Sui, and Bo Sun
Atmos. Chem. Phys., 23, 345–353, https://doi.org/10.5194/acp-23-345-2023, https://doi.org/10.5194/acp-23-345-2023, 2023
Short summary
Short summary
Previous studies have noted a significant relationship between the Subtropical Indian Ocean Dipole and the South Atlantic Ocean Dipole indices, but little is known about the stability of their relationship. We found a significant positive correlation between the two indices prior to the year 2000 but an insignificant correlation afterwards.
Si Cheng, Jianguo Wang, Li Cai, Mi Zhou, Rui Su, Yijun Huang, and Quanxin Li
Atmos. Chem. Phys., 22, 10045–10059, https://doi.org/10.5194/acp-22-10045-2022, https://doi.org/10.5194/acp-22-10045-2022, 2022
Short summary
Short summary
This paper helps to improve the recognition of severe thunderstorms in advance by giving a general understanding of how long the storm lasts, how fast the cluster moves and how much area the storm affects via information about the kinematic features of thunderstorms, which are the duration, valid area, the velocity, the direction and the farthest distance, and ideally to establish a foundation for future research that may contribute to the development of a new or improved prediction paradigm.
Hongyou Liu, Yanxiong Shi, and Xiaojing Zheng
Atmos. Chem. Phys., 22, 8787–8803, https://doi.org/10.5194/acp-22-8787-2022, https://doi.org/10.5194/acp-22-8787-2022, 2022
Short summary
Short summary
The sandstorm, which is a common natural disaster, is mechanically characterized by a particle-laden flow experiencing wall turbulence. This work investigates a real sandstorm that was measured at the Qingtu Lake Observation Array through a lens of wall-turbulent flow dynamics. A non-stationary signal processing method is proposed based on the time-varying mean and adaptive segmented stationary method, and the evolution of turbulent kinetic energy during the entire sandstorm process is revealed.
Simon Kirschler, Christiane Voigt, Bruce Anderson, Ramon Campos Braga, Gao Chen, Andrea F. Corral, Ewan Crosbie, Hossein Dadashazar, Richard A. Ferrare, Valerian Hahn, Johannes Hendricks, Stefan Kaufmann, Richard Moore, Mira L. Pöhlker, Claire Robinson, Amy J. Scarino, Dominik Schollmayer, Michael A. Shook, K. Lee Thornhill, Edward Winstead, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 8299–8319, https://doi.org/10.5194/acp-22-8299-2022, https://doi.org/10.5194/acp-22-8299-2022, 2022
Short summary
Short summary
In this study we show that the vertical velocity dominantly impacts the cloud droplet number concentration (NC) of low-level clouds over the western North Atlantic in the winter and summer season, while the cloud condensation nuclei concentration, aerosol size distribution and chemical composition impact NC within a season. The observational data presented in this study can evaluate and improve the representation of aerosol–cloud interactions for a wide range of conditions.
Klaus Gierens, Lena Wilhelm, Sina Hofer, and Susanne Rohs
Atmos. Chem. Phys., 22, 7699–7712, https://doi.org/10.5194/acp-22-7699-2022, https://doi.org/10.5194/acp-22-7699-2022, 2022
Short summary
Short summary
We are interested in the prediction of condensation trails, in particular strong ones. For this we need a good forecast of temperature and humidity in the levels where aircraft cruise. Unfortunately, the humidity forecast is quite difficult for these levels, in particular the ice supersaturation, which is needed for long-lasting contrails. We are thus seeking proxy variables that help distinguish situations where strong contrails can form, for instance the lapse rate.
Ada Mariska Koning, Louise Nuijens, Christian Mallaun, Benjamin Witschas, and Christian Lemmerz
Atmos. Chem. Phys., 22, 7373–7388, https://doi.org/10.5194/acp-22-7373-2022, https://doi.org/10.5194/acp-22-7373-2022, 2022
Short summary
Short summary
Wind measurements from the mixed layer to cloud tops are scarce, causing a lack of knowledge on wind mixing between and within these layers. We use airborne observations of wind profiles and local wind at high frequency to study wind transport in cloud fields. A case with thick clouds had its maximum transport in the cloud layer, caused by eddies > 700 m, which was not expected from turbulence theory. In other cases large eddies undid transport of smaller eddies resulting in no net transport.
Markus Geldenhuys, Peter Preusse, Isabell Krisch, Christoph Zülicke, Jörn Ungermann, Manfred Ern, Felix Friedl-Vallon, and Martin Riese
Atmos. Chem. Phys., 21, 10393–10412, https://doi.org/10.5194/acp-21-10393-2021, https://doi.org/10.5194/acp-21-10393-2021, 2021
Short summary
Short summary
A large-scale gravity wave (GW) was observed spanning the whole of Greenland. The GWs proposed in this paper come from a new jet–topography mechanism. The topography compresses the flow and triggers a change in u- and
v-wind components. The jet becomes out of geostrophic balance and sheds energy in the form of GWs to restore the balance. This topography–jet interaction was not previously considered by the community, rendering the impact of the gravity waves largely unaccounted for.
Kristina Pistone, Paquita Zuidema, Robert Wood, Michael Diamond, Arlindo M. da Silva, Gonzalo Ferrada, Pablo E. Saide, Rei Ueyama, Ju-Mee Ryoo, Leonhard Pfister, James Podolske, David Noone, Ryan Bennett, Eric Stith, Gregory Carmichael, Jens Redemann, Connor Flynn, Samuel LeBlanc, Michal Segal-Rozenhaimer, and Yohei Shinozuka
Atmos. Chem. Phys., 21, 9643–9668, https://doi.org/10.5194/acp-21-9643-2021, https://doi.org/10.5194/acp-21-9643-2021, 2021
Short summary
Short summary
Using aircraft-based measurements off the Atlantic coast of Africa, we found the springtime smoke plume was strongly correlated with the amount of water vapor in the atmosphere (more smoke indicated more humidity). We see the same general feature in satellite-assimilated and free-running models. Our analysis suggests this relationship is not caused by the burning but originates due to coincident continental meteorology plus fires. This air is transported over the ocean without further mixing.
Markku Kulmala, Tom V. Kokkonen, Juha Pekkanen, Sami Paatero, Tuukka Petäjä, Veli-Matti Kerminen, and Aijun Ding
Atmos. Chem. Phys., 21, 8313–8322, https://doi.org/10.5194/acp-21-8313-2021, https://doi.org/10.5194/acp-21-8313-2021, 2021
Short summary
Short summary
The eastern part of China as a whole is practically a gigacity with 650 million inhabitants. The gigacity, with its emissions, processes in the pollution cocktail and numerous feedbacks and interactions, has a crucial and big impact on regional air quality and on global climate. A large-scale research and innovation program is needed to meet the interlinked grand challenges in this gigacity and to serve as a platform for finding pathways for sustainable development of the globe.
Yunyan Jiang, Jinyuan Xin, Ying Wang, Guiqian Tang, Yuxin Zhao, Danjie Jia, Dandan Zhao, Meng Wang, Lindong Dai, Lili Wang, Tianxue Wen, and Fangkun Wu
Atmos. Chem. Phys., 21, 6111–6128, https://doi.org/10.5194/acp-21-6111-2021, https://doi.org/10.5194/acp-21-6111-2021, 2021
Short summary
Short summary
Multiscale-circulation coupling affects pollution by changing the planetary boundary layer (PBL) structure. The multilayer PBL under cyclonic circulation has no diurnal variation; the temperature inversion and zero-speed zone can reach 600–900 m with strong mountain winds. The monolayer PBL under southwestern circulation can reach 2000 m; the inversion is lower than nocturnal PBL (400 m) with strong ambient winds. The zonal winds' vertical shear produces the inversion under western circulation.
Dillon S. Dodson and Jennifer D. Small Griswold
Atmos. Chem. Phys., 21, 1937–1961, https://doi.org/10.5194/acp-21-1937-2021, https://doi.org/10.5194/acp-21-1937-2021, 2021
Short summary
Short summary
The results here reinforce findings from previous in situ studies of the marine boundary layer. It is found that turbulence is maximized in the middle of the stratocumulus layer from latent heating effects. Precipitation acts to increase turbulence in the sub-cloud layer, while acting to stabilize the entire boundary layer after the evaporation of precipitation in the sub-cloud has stopped. A negative correlation is present between the boundary layer height and turbulence.
Ju Li, Zhaobin Sun, Donald H. Lenschow, Mingyu Zhou, Youjun Dou, Zhigang Cheng, Yaoting Wang, and Qingchun Li
Atmos. Chem. Phys., 20, 15793–15809, https://doi.org/10.5194/acp-20-15793-2020, https://doi.org/10.5194/acp-20-15793-2020, 2020
Short summary
Short summary
We analyzed a haze front event involving warm–dry downslope flow in December 2015 in Beijing, China. The haze front was formed by the collision between a clean warm–dry air mass flowing from a nearby mountainous region and a polluted cold–wet air mass over an urban area. We found that the polluted air advanced toward the clean air, resulting in a severe air pollution event. Our study highlights the need to further investigate the warm–dry downslope and its impacts on air pollution.
Sonja Gisinger, Johannes Wagner, and Benjamin Witschas
Atmos. Chem. Phys., 20, 10091–10109, https://doi.org/10.5194/acp-20-10091-2020, https://doi.org/10.5194/acp-20-10091-2020, 2020
Short summary
Short summary
Gravity waves are an important coupling mechanism in the atmosphere. Measurements by two research aircraft during a mountain wave event over Scandinavia in 2016 revealed changes of the horizontal scales in the vertical velocity field and of momentum fluxes in the vicinity of the tropopause inversion. Idealized simulations revealed the presence of interfacial waves. They are found downstream of the mountain peaks, meaning that they horizontally transport momentum/energy away from their source.
Rayonil G. Carneiro and Gilberto Fisch
Atmos. Chem. Phys., 20, 5547–5558, https://doi.org/10.5194/acp-20-5547-2020, https://doi.org/10.5194/acp-20-5547-2020, 2020
Short summary
Short summary
The objective of this study was to conduct observational evaluations of the daily cycle of the height of the planetary boundary layer from data that were measured and/or estimated using instruments such as a radiosonde, sodar, ceilometer, wind profiler, lidar and microwave radiometer installed in the central Amazon during 2014 (considered a typical year) and 2015 during which an intense El Niño–Southern Oscillation (ENSO) event predominated during the GoAmazon experiment.
Maurício I. Oliveira, Otávio C. Acevedo, Matthias Sörgel, Ernani L. Nascimento, Antonio O. Manzi, Pablo E. S. Oliveira, Daiane V. Brondani, Anywhere Tsokankunku, and Meinrat O. Andreae
Atmos. Chem. Phys., 20, 15–27, https://doi.org/10.5194/acp-20-15-2020, https://doi.org/10.5194/acp-20-15-2020, 2020
Short summary
Short summary
In this study, data collected during four deep convection events at the 80 m tower from the Amazon Tall Tower Observatory are analyzed. It provides a unique view on how such events affect the local boundary layer and how it recovers after their passage. Quantities analyzed include mean wind speed, virtual potential temperature, turbulent kinetic energy, sensible, and latent heat fluxes. A conceptual model for boundary layer structure along the passage of deep convection events is proposed.
Zhicong Yin, Bufan Cao, and Huijun Wang
Atmos. Chem. Phys., 19, 13933–13943, https://doi.org/10.5194/acp-19-13933-2019, https://doi.org/10.5194/acp-19-13933-2019, 2019
Short summary
Short summary
Ozone occurs both in the stratosphere and at ground level. Surface ozone is a man-made air pollutant and has harmful effects on people and the environment. Two dominant patterns of summer ozone pollution were determined. The most dominant pattern in 2017 and 2018 was different from that in previous years. The findings of this study help us to understand the features of surface ozone pollution in eastern China and their relationships with large-scale atmospheric circulations.
Karmen Babić, Norbert Kalthoff, Bianca Adler, Julian F. Quinting, Fabienne Lohou, Cheikh Dione, and Marie Lothon
Atmos. Chem. Phys., 19, 13489–13506, https://doi.org/10.5194/acp-19-13489-2019, https://doi.org/10.5194/acp-19-13489-2019, 2019
Short summary
Short summary
This study investigates differences in atmospheric conditions between nights with and without low-level stratus clouds (LLCs) over southern West Africa. We use high-quality observations collected during 2016 summer monsoon season and the ERA5 reanalysis data set. Our results show that the formation of LLCs depends on the interplay between the onset time and strength of the nocturnal low-level jet, horizontal cold-air advection, and the overall moisture level in the whole region.
Justine Ringard, Marjolaine Chiriaco, Sophie Bastin, and Florence Habets
Atmos. Chem. Phys., 19, 13129–13155, https://doi.org/10.5194/acp-19-13129-2019, https://doi.org/10.5194/acp-19-13129-2019, 2019
Short summary
Short summary
This study characterizes the changes observed at Paris urban scale and attempts to identify the surface–atmosphere feedbacks likely to explain the trends observed as a function of the different configurations of large-scale dynamics. This article is interested in several atmospheric parameters and their possible retroactions. Finally, to study urban environments, the analysis at the local scale is essential because it is very poorly represented in the model.
Jesús Yus-Díez, Mireia Udina, Maria Rosa Soler, Marie Lothon, Erik Nilsson, Joan Bech, and Jielun Sun
Atmos. Chem. Phys., 19, 9495–9514, https://doi.org/10.5194/acp-19-9495-2019, https://doi.org/10.5194/acp-19-9495-2019, 2019
Short summary
Short summary
This study helps improve the understanding of the turbulence description and the interactions occurring in the lower part of the boundary layer. It is carried out at an orographically influenced site close to the Pyrenees to explore the hockey-stick transition (HOST) theory. HOST is seen to be strongly dependent on both the meteorological conditions and the orographic features. Examples of intermittent turbulence events that lead to transitions between the turbulence regimes are also identified.
Cheikh Dione, Fabienne Lohou, Marie Lothon, Bianca Adler, Karmen Babić, Norbert Kalthoff, Xabier Pedruzo-Bagazgoitia, Yannick Bezombes, and Omar Gabella
Atmos. Chem. Phys., 19, 8979–8997, https://doi.org/10.5194/acp-19-8979-2019, https://doi.org/10.5194/acp-19-8979-2019, 2019
Short summary
Short summary
Low atmospheric dynamics and low-level cloud (LLC) macrophysical properties are analyzed using in situ and remote sensing data collected from 20 June to 30 July at Savè, Benin, during the DACCIWA field campaign in 2016. We find that the low-level jet (LLJ), LLCs, monsoon flow, and maritime inflow reveal a day-to-day variability. LLCs form at the same level as the jet core height. The cloud base height is stationary at night and remains below the jet. The cloud top height is found above the jet.
Dani J. Caputi, Ian Faloona, Justin Trousdell, Jeanelle Smoot, Nicholas Falk, and Stephen Conley
Atmos. Chem. Phys., 19, 4721–4740, https://doi.org/10.5194/acp-19-4721-2019, https://doi.org/10.5194/acp-19-4721-2019, 2019
Short summary
Short summary
This paper covers the importance of understanding ozone pollution in California’s southern San Joaquin Valley from the perspective of meteorological conditions that occur overnight. Our main finding is that stronger winds aloft allow ozone to be depleted overnight, leading to less ozone the following day. This finding has the potential to greatly improve ozone forecasts in the San Joaquin Valley. This study is primarily conducted with aircraft observations.
Étienne Vignon, Olivier Traullé, and Alexis Berne
Atmos. Chem. Phys., 19, 4659–4683, https://doi.org/10.5194/acp-19-4659-2019, https://doi.org/10.5194/acp-19-4659-2019, 2019
Short summary
Short summary
The future sea-level rise will depend on how much the Antarctic ice sheet gain – via precipitation – or loose mass. The simulation of precipitation by numerical models used for projections depends on the representation of the atmospheric circulation over and around Antarctica. Using daily measurements from balloon soundings at nine Antarctic stations, this study characterizes the structure of the atmosphere over the Antarctic coast and its representation in atmospheric simulations.
Nicola Bodini, Julie K. Lundquist, Raghavendra Krishnamurthy, Mikhail Pekour, Larry K. Berg, and Aditya Choukulkar
Atmos. Chem. Phys., 19, 4367–4382, https://doi.org/10.5194/acp-19-4367-2019, https://doi.org/10.5194/acp-19-4367-2019, 2019
Short summary
Short summary
To improve the parameterization of the turbulence dissipation rate (ε) in numerical weather prediction models, we have assessed its temporal and spatial variability at various scales in the Columbia River Gorge during the WFIP2 field experiment. The turbulence dissipation rate shows large spatial variability, even at the microscale, with larger values in sites located downwind of complex orographic structures or in wind farm wakes. Distinct diurnal and seasonal cycles in ε have also been found.
Frederick Letson, Rebecca J. Barthelmie, Weifei Hu, and Sara C. Pryor
Atmos. Chem. Phys., 19, 3797–3819, https://doi.org/10.5194/acp-19-3797-2019, https://doi.org/10.5194/acp-19-3797-2019, 2019
Short summary
Short summary
Wind gusts are a key driver of aerodynamic loading, and common approximations used to describe wind gust behavior may not be appropriate in complex terrain at heights relevant to wind turbines and other structures. High-resolution observations from sonic anemometers and vertically pointing Doppler lidars collected in the Perdigão experiment are analyzed to provide a foundation for improved wind gust characterization in complex terrain.
Rohit Chakraborty, Madineni Venkat Ratnam, and Shaik Ghouse Basha
Atmos. Chem. Phys., 19, 3687–3705, https://doi.org/10.5194/acp-19-3687-2019, https://doi.org/10.5194/acp-19-3687-2019, 2019
Short summary
Short summary
Intense convective phenomena are a common climatic feature in the Indian tropical region which occur during the pre-monsoon to post-monsoon seasons (April–October) and are generally accompanied by intense thunderstorms, lightning, and wind gusts with heavy rainfall. Here we show long-term trends of the parameters related to convection and instability obtained from 27 radiosonde stations across six subdivisions over the Indian region during the period 1980–2016.
Kunihiko Kodera, Nawo Eguchi, Rei Ueyama, Yuhji Kuroda, Chiaki Kobayashi, Beatriz M. Funatsu, and Chantal Claud
Atmos. Chem. Phys., 19, 2655–2669, https://doi.org/10.5194/acp-19-2655-2019, https://doi.org/10.5194/acp-19-2655-2019, 2019
Short summary
Short summary
The recent cooling of the equatorial eastern Pacific Ocean occurred in conjunction with enhanced cross-equatorial southerlies associated with a strengthening of the boreal summer Hadley circulation. A combination of land surface warming and reduced static stability in the tropical tropopause layer due to stratospheric cooling is suggested to have caused the increase in the deep ascending branch of the Hadley circulation and related recent decadal change in the tropical troposphere and ocean.
Karmen Babić, Bianca Adler, Norbert Kalthoff, Hendrik Andersen, Cheikh Dione, Fabienne Lohou, Marie Lothon, and Xabier Pedruzo-Bagazgoitia
Atmos. Chem. Phys., 19, 1281–1299, https://doi.org/10.5194/acp-19-1281-2019, https://doi.org/10.5194/acp-19-1281-2019, 2019
Short summary
Short summary
The first detailed observational analysis of the complete diurnal cycle of low-level clouds (LLC) and associated atmospheric processes over southern West Africa is performed using the data gathered within the DACCIWA (Dynamics-Aerosol-Chemistry-Cloud-Interactions in West Africa) ground-based campaign. We find cooling related to the horizontal advection, which occurs in connection with the inflow of cool maritime air mass and a prominent low-level jet, to have the dominant role in LLC formation.
Bianca Adler, Karmen Babić, Norbert Kalthoff, Fabienne Lohou, Marie Lothon, Cheikh Dione, Xabier Pedruzo-Bagazgoitia, and Hendrik Andersen
Atmos. Chem. Phys., 19, 663–681, https://doi.org/10.5194/acp-19-663-2019, https://doi.org/10.5194/acp-19-663-2019, 2019
Short summary
Short summary
This study deals with nocturnal stratiform low-level clouds that frequently form in the atmospheric boundary layer over southern West Africa. We use observational data from 11 nights to characterize the clouds and intranight variability of boundary layer conditions as well as to assess the physical processes relevant for cloud formation. We find that cooling is crucial to reach saturation and a large part of the cooling is related to horizontal advection of cool air from the Gulf of Guinea.
Jutta Vüllers, Georg J. Mayr, Ulrich Corsmeier, and Christoph Kottmeier
Atmos. Chem. Phys., 18, 18169–18186, https://doi.org/10.5194/acp-18-18169-2018, https://doi.org/10.5194/acp-18-18169-2018, 2018
Short summary
Short summary
This paper investigates frequently occurring foehn at the Dead Sea, which strongly impacts the local climatic conditions, in particular temperature and humidity, as well as evaporation from the Dead Sea, the aerosol load, and visibility. A statistical classification exposes two types of foehn and first-time, high-resolution measurements reveal trigger mechanisms and relevant characteristics, such as wind velocities, affected air layers, and resulting phenomena such as hydraulic jumps and rotors.
Cited articles
AEMET: Summary of Summer 2017, Spanish Meteorological Agency,
available at: http://www.aemet.es/en/noticias/2017/09/Verano_2017 (last access: 13 August 2018), 2017.
Arrillaga, J. A., Vilà-Guerau de Arellano, J., Bosveld, F., Baltink, H. K.,
Yagüe, C., Sastre, M., and Román-Cascón, C.: Impacts of afternoon and
evening sea-breeze fronts on local turbulence, and on CO2 and radon-222
transport, Q. J. Roy. Meteor. Soc., 144, 990–1011,
https://doi.org/10.1002/qj.3252, 2018.
Atkinson, B.: Meso-Scale Atmospheric Circulations, Academic Press, London,
1981.
Banta, R. M. and Gannon, P. T.: Influence of soil moisture on simulations of
katabatic flow, Theor. Appl. Climatol., 52, 85–94,
https://doi.org/10.1007/BF00865509, 1995.
Barry, R. G.: Mountain Weather and Climate, Cambridge University Press,
Cambridge, UK, Meteorol. Appl., 17, 506 pp.,
https://doi.org/10.1002/met.222, 2008.
Borge, R., Narros, A., Artíñano, B., Yagüe, C., Gómez-Moreno, F. J., de la
Paz, D., Román-Cascón, C., Díaz, E., Maqueda, G., Sastre, M., Quaassdorff,
C., Dimitroulopoulou, C., and Vardoulakis, S.: Assessment of microscale
spatio-temporal variation of air pollution at an urban hotspot in Madrid
(Spain) through an extensive field campaign, Atmos. Environ., 140, 432–445, https://doi.org/10.1016/j.atmosenv.2016.06.020, 2016.
Borge, R., Artíñano, B., Yagüe, C., Gomez-Moreno, F. J., Saiz-Lopez, A.,
Sastre, M., Narros, A., García-Nieto, D., Benavent, N., Maqueda, G.,
Barreiro, M., de Andrés, J. M., and Cristóbal, A.: Application of a
short term air quality action plan in Madrid (Spain) under a high-pollution
episode – Part I: Diagnostic and analysis from observations, Sci. Total
Environ., 635, 1561–1573,
https://doi.org/10.1016/j.scitotenv.2018.03.149, 2018.
Campbell-Scientific: EasyFlux DL Eddy-Covariance CR3000 Datalogger Program,
available at: https://s.campbellsci.com/documents/us/product-brochures/b_easyflux-dl.pdf (15 February 2019), 2017.
Casso-Torralba, P., Vilà-Guerau de Arellano, J., Bosveld, F., Soler, M. R.,
Vermeulen, A., Werner, C., and Moors, E.: Diurnal and vertical variability of
the sensible heat and carbon dioxide budgets in the atmospheric surface
layer, J. Geophys. Res.-Atmos., 113, d12119,
https://doi.org/10.1029/2007JD009583, 2008.
Chrust, M. F., Whiteman, C. D., and Hoch, S. W.: Observations of Thermally
Driven Wind Jets at the Exit of Weber Canyon, Utah, J. Appl. Meteorol. Clim.,
52, 1187–1200, https://doi.org/10.1175/JAMC-D-12-0221.1,
2013.
Cristofanelli, P., Calzolari, F., Bonafè, U., Lanconelli, C., Lupi, A.,
Busetto, M., Vitale, V., Colombo, T., and Bonasoni, P.: Five-year analysis of
background carbon dioxide and ozone variations during summer seasons at the
Mario Zucchelli station (Antarctica), Tellus B, 63, 831–842,
https://doi.org/10.1111/j.1600-0889.2011.00576.x, 2011.
Detto, M., Montaldo, N., Albertson, J. D., Mancini, M., and Katul, G.: Soil
moisture and vegetation controls on evapotranspiration in a heterogeneous
Mediterranean ecosystem on Sardinia, Italy, Water Resour. Res., 42, 1–16,
https://doi.org/10.1029/2005WR004693, 2006.
Doran, J. C.: The effects of ambient winds on valley drainage flows,
Bound.-Lay. Meteorol., 55, 177–189,
https://doi.org/10.1007/BF00119333, 1991.
Durán, L., Sánchez, E., and Yagüe, C.: Climatology of precipitation over the
Iberian Central System mountain range, Int. J. Climatol., 33, 2260–2273,
https://doi.org/10.1002/joc.3602, 2013.
Durán, L., Rodríguez-Muñoz, I., and Sánchez, E.: The Peñalara Mountain
Meteorological Network (1999–2014): Description, Preliminary Results and
Lessons Learned, Atmosphere, 8, 1–25,
https://doi.org/10.3390/atmos8100203, 2018.
Fitzjarrald, D. R.: Katabatic Wind in Opposing Flow, J. Atmos. Sci., 41,
1143–1158,
https://doi.org/10.1175/1520-0469(1984)041<1143:KWIOF>2.0.CO;2, 1984.
Flocas, H. A., Helmis, C. G., Blikas, S. N., Asimakopoulos, D. N., Bartzis,
J. G., and Deligiorgi, D. G.: Mean Characteristics of the Katabatic Flow of a
1024 m High Knife Edge Mountain, Theor. Appl. Climatol., 59,
237–249, https://doi.org/10.1007/s007040050027, 1998.
Grachev, A. A., Leo, L. S., Di Sabatino, S., Fernando, H. J. S., Pardyjak,
E. R., and Fairall, C. W.: Structure of Turbulence in Katabatic Flows Below
and Above the Wind-Speed Maximum, Bound.-Lay. Meteorol., 159, 469–494,
https://doi.org/10.1007/s10546-015-0034-8, 2016.
GuMNet: https://www.ucm.es/gumnet/ (last access: 29 March 2019), 2019.
Hang, C., Nadeau, D. F., Gultepe, I., Hoch, S. W., Román-Cascón, C.,
Pryor, K., Fernando, H. J. S., Creegan, E. D., Leo, L. S., Silver, Z., and
Pardyjak, E. R.: A Case Study of the Mechanisms Modulating the Evolution of
Valley Fog, Pure Appl. Geophys., 173, 3011–3030,
https://doi.org/10.1007/s00024-016-1370-4, 2016.
Horst, T. W. and Doran, J. C.: Nocturnal drainage flow on simple slopes,
Bound.-Lay. Meteorol., 34, 263–286,
https://doi.org/10.1007/BF00122382, 1986.
Hsieh, C. I., Katul, G., and Chi, T.-W.: An approximate analytical model for
footprint estimation of scalar fluxes in thermally stratified atmospheric
flows, Adv. Water Resour., 23, 765–772,
https://doi.org/10.1016/S0309-1708(99)00042-1, 2000.
Jacobs, A. F. G., Heusinkveld, B. G., and Holtslag, A. A. M.: Seasonal and
interannual variability of carbon dioxide and water balances of a grassland,
Clim. Change, 82, 163–177,
https://doi.org/10.1007/s10584-006-9182-7, 2007a.
Jacobs, C. M. J., Jacobs, A. F. G., Bosveld, F. C., Hendriks, D. M. D.,
Hensen, A., Kroon, P. S., Moors, E. J., Nol, L., Schrier-Uijl, A., and
Veenendaal, E. M.: Variability of annual CO2 exchange from Dutch grasslands,
Biogeosciences, 4, 803–816, https://doi.org/10.5194/bg-4-803-2007, 2007b.
Jensen, D., Nadeau, D. F., Hoch, S. W., and Pardyjak, E. R.: The evolution and
sensitivity of katabatic flow dynamics to external influences through the
evening transition, Q. J. Roy. Meteor. Soc., 143, 423–438,
https://doi.org/10.1002/qj.2932, 2017.
Jiménez, M. A., Cuxart, J., and Martínez-Villagrasa, D.: Influence of a
valley exit jet on the nocturnal atmospheric boundary layer at the foothills
of the Pyrenees, Q. J. Roy. Meteor. Soc., 145, 356–375,
https://doi.org/10.1002/qj.3437, 2019.
Kaimal, J. and Finnigan, J.: Atmospheric Boundary Layer Flows: Their Structure
and Measurements, Oxford University Press, Oxford, 289 pp., 1994.
Kaimal, J. C., Clifford, S. F., and Lataitis, R. J.: Effect of finite sampling
on atmospheric spectra, Bound.-Lay. Meteor., 47, 337–347,
https://doi.org/10.1007/BF00122338, 1989.
Legrand, M., Preunkert, S., Savarino, J., Frey, M. M., Kukui, A., Helmig, D.,
Jourdain, B., Jones, A. E., Weller, R., Brough, N., and Gallée, H.:
Inter-annual variability of surface ozone at coastal (Dumont d'Urville,
2004–2014) and inland (Concordia, 2007–2014) sites in East Antarctica, Atmos.
Chem. Phys., 16, 8053–8069, https://doi.org/10.5194/acp-16-8053-2016, 2016.
Lehner, M., Whiteman, C. D., Hoch, S. W., Jensen, D., Pardyjak, E. R., Leo,
L. S., Di Sabatino, S., and Fernando, H. J. S.: A Case Study of the Nocturnal
Boundary Layer Evolution on a Slope at the Foot of a Desert Mountain, J.
Appl. Meteorol. Clim., 54, 732–751,
https://doi.org/10.1175/JAMC-D-14-0223.1, 2015.
Li, J., Sun, J., Zhou, M., Cheng, Z., Li, Q., Cao, X., and Zhang, J.:
Observational analyses of dramatic developments of a severe air pollution
event in the Beijing area, Atmos. Chem. Phys., 18, 3919–3935,
https://doi.org/10.5194/acp-18-3919-2018, 2018.
Lloyd, J. and Taylor, J.: On the Temperature Dependence of Soil Respiration,
Funct. Ecol., 8, 315–323, https://doi.org/10.2307/2389824,
1994.
Lothon, M., Lohou, F., Pino, D., Couvreux, F., Pardyjak, E. R., Reuder, J.,
Vilà-Guerau de Arellano, J., Durand, P., Hartogensis, O., Legain, D.,
Augustin, P., Gioli, B., Lenschow, D. H., Faloona, I., Yagüe, C., Alexander,
D. C., Angevine, W. M., Bargain, E., Barrié, J., Bazile, E., Bezombes, Y.,
Blay-Carreras, E., van de Boer, A., Boichard, J. L., Bourdon, A., Butet, A.,
Campistron, B., de Coster, O., Cuxart, J., Dabas, A., Darbieu, C., Deboudt,
K., Delbarre, H., Derrien, S., Flament, P., Fourmentin, M., Garai, A.,
Gibert, F., Graf, A., Groebner, J., Guichard, F., Jiménez, M. A., Jonassen,
M., van den Kroonenberg, A., Magliulo, V., Martin, S., Martinez, D.,
Mastrorillo, L., Moene, A. F., Molinos, F., Moulin, E., Pietersen, H. P.,
Piguet, B., Pique, E., Román-Cascón, C., Rufin-Soler, C., Saïd, F.,
Sastre-Marugán, M., Seity, Y., Steeneveld, G. J., Toscano, P., Traullé, O.,
Tzanos, D., Wacker, S., Wildmann, N., and Zaldei, A.: The BLLAST field
experiment: Boundary-Layer Late Afternoon and Sunset Turbulence, Atmos. Chem.
Phys., 14, 10931–10960, https://doi.org/10.5194/acp-14-10931-2014, 2014.
Mahrt, L.: Nocturnal Boundary-Layer Regimes, Bound.-Lay. Meteorol., 88,
255–278, https://doi.org/10.1023/A:1001171313493, 1998.
Mahrt, L.: Stably Stratified Atmospheric Boundary Layers, Annu. Rev. Fluid
Mech., 46, 23–45,
https://doi.org/10.1146/annurev-fluid-010313-141354, 2014.
Mahrt, L. and Larsen, S.: Relation of slope winds to the ambient flow over
gentle terrain, Bound.-Lay. Meteorol., 53, 93–102,
https://doi.org/10.1007/BF00122465, 1990.
Mahrt, L., Vickers, D., Nakamura, R., Soler, M. R., Sun, J., Burns, S., and
Lenschow, D.: Shallow Drainage Flows, Bound.-Lay. Meteorol., 101,
243–260, https://doi.org/10.1023/A:1019273314378, 2001.
Manins, P. C. and Sawford, B. L.: A Model of Katabatic Winds, J. Atmos. Sci.,
36, 619–630,
https://doi.org/10.1175/1520-0469(1979)036<0619:AMOKW>2.0.CO;2, 1979.
Mauritsen, T. and Svensson, G.: Observations of Stably Stratified Shear-Driven
Atmospheric Turbulence at Low and High Richardson Numbers, J. Atmos. Sci.,
64, 645–655, https://doi.org/10.1175/JAS3856.1, 2007.
Nadeau, D., Pardyjak, E. R., Higgins, C. W., Huwald, H., and Parlange, M. B.:
Flow during the evening transition over steep Alpine slopes, Q. J. Roy.
Meteor. Soc., 139, 607–624,
https://doi.org/10.1002/qj.1985, 2013.
Oldroyd, H. J., Pardyjak, E. R., Higgins, C. W., and Parlange, M. B.: Buoyant
Turbulent Kinetic Energy Production in Steep-Slope Katabatic Flow,
Bound.-Lay. Meteor., 161, 405–416,
https://doi.org/10.1007/s10546-016-0184-3, 2016.
Papadopoulos, K. H. and Helmis, C. G.: Evening and Morning Transition of
Katabatic Flows, Bound.-Lay. Meteor., 92, 195–227,
https://doi.org/10.1023/A:1002070526425, 1999.
Pardyjak, E. R., Fernando, H. J. S., Hunt, J. C., Grachev, A. A., and Anderson,
J. A.: A case study of the development of nocturnal slope flows in a wide
open valley and associated air quality implications, Meteorol. Z., 18,
85–100, https://doi.org/10.1127/0941-2948/2009/362, 2009.
Plaza, J., Pujadas, M., and Artíñano, B.: Formation and Transport of the
Madrid Ozone Plume, J. Air Waste Manage. Assoc., 47, 766–774,
https://doi.org/10.1080/10473289.1997.10463938, 1997.
Poulos, G. and Zhong, S.: An Observational History of Small-Scale Katabatic
Winds in Mid-Latitudes, Geogr. Compass, 2, 1798–1821,
https://doi.org/10.1111/j.1749-8198.2008.00166.x, 2008.
Poulos, G. S., Blumen, W., Fritts, D. C., Lundquist, J. K., Sun, J., Burns,
S. P., Nappo, C., Banta, R., Newsom, R., Cuxart, J., Terradellas, E.,
Balsley, B., and Jensen, M.: CASES-99: A Comprehensive Investigation of the
Stable Nocturnal Boundary Layer, B. Am. Meteor. Soc., 83, 555–582,
https://doi.org/10.1175/1520-0477(2002)083<0555:CACIOT>2.3.CO;2, 2002.
Román-Cascón, C., Yagüe, C., Mahrt, L., Sastre, M., Steeneveld, G.-J.,
Pardyjak, E., van de Boer, A., and Hartogensis, O.: Interactions among
drainage flows, gravity waves and turbulence: a BLLAST case study, Atmos.
Chem. Phys., 15, 9031–9047, https://doi.org/10.5194/acp-15-9031-2015, 2015.
Román-Cascón, C., Yagüe, C., Arrillaga, J., Lothon, M., Pardyjak, E., Lohou,
F., Inclán, R., Sastre, M., Maqueda, G., Derrien, S., Meyerfeld, Y., Hang,
C., Campargue-Rodríguez, P., and Turki, I.: Comparing mountain breezes and
their impacts on CO2 mixing ratios at three contrasting areas, Atmos. Res.,
221, 111–126,
https://doi.org/10.1016/j.atmosres.2019.01.019, 2019.
Rotach, M. W., Wohlfahrt, G., Hansel, A., Reif, M., Wagner, J., and Gohm, A.:
The World is Not Flat: Implications for the Global Carbon Balance, B. Am.
Meteor. Soc., 95, 1021–1028,
https://doi.org/10.1175/BAMS-D-13-00109.1, 2014.
Sastre, M., Yagüe, C., Román-Cascón, C., and Maqueda, G.: Atmospheric
Boundary-Layer Evening Transitions: A Comparison Between Two Different
Experimental Sites, Bound.-Lay. Meteorol., 157, 375–399,
https://doi.org/10.1007/s10546-015-0065-1, 2015.
Schotanus, P., Nieuwstadt, F., and de Bruin, H.: Temperature-Measurement with a
Sonic Anemometer and Its Application to Heat and Moisture Fluxes,
Bound.-Lay. Meteorol., 26, 81–93,
https://doi.org/10.1007/BF00164332, 1983.
Soler, M., Infante, C., Buenestado, P., and Mahrt, L.: Observations Of
Nocturnal Drainage Flow In A Shallow Gully, Bound.-Lay. Meteorol., 105,
253–273, https://doi.org/10.1023/A:1019910622806, 2002.
Steeneveld, G. J., Wokke, M. J. J., Groot Zwaaftink, C. D., Pijlman, S.,
Heusinkveld, B. G., Jacobs, A. F. G., and Holtslag, A. A. M.: Observations of
the radiation divergence in the surface layer and its implication for its
parameterization in numerical weather prediction models, J. Geophys. Res.-Atmos., 115, 1–13, https://doi.org/10.1029/2009JD013074,
2010.
Sun, H., Clark, T. L., Stull, R. B., and Black, T. A.: Two-dimensional
simulation of airflow and carbon dioxide transport over a forested mountain:
Part II, Carbon dioxide budget analysis and advection effects, Agric. For.
Meteorol., 140, 352–364,
https://doi.org/10.1016/j.agrformet.2006.03.016, 2006.
Sun, J., Burns, S. P., Delany, A. C., Oncley, S. P., Turnipseed, A. A.,
Stephens, B. B., Lenschow, D. H., LeMone, M. A., Monson, R. K., and Anderson,
D. E.: CO2 transport over complex terrain, Agric. For. Meteorol., 145, 1–21, https://doi.org/10.1016/j.agrformet.2007.02.007, 2007.
Sun, J., Mahrt, L., Banta, R. M., and Pichugina, Y. L.: Turbulence Regimes and
Turbulence Intermittency in the Stable Boundary Layer during CASES-99, J.
Atmos. Sci., 69, 338–351,
https://doi.org/10.1175/JAS-D-11-082.1, 2012.
Sun, J., Mahrt, L., Nappo, C., and Lenschow, D. H.: Wind and Temperature
Oscillations Generated by Wave–Turbulence Interactions in the Stably
Stratified Boundary Layer, J. Atmos. Sci., 72, 1484–1503,
https://doi.org/10.1175/JAS-D-14-0129.1, 2015.
Terradellas, E. and Cano, D.: Implementation of a Single-Column Model for Fog
and Low Cloud Forecasting at Central-Spanish Airports, Pure Appl. Geophys.,
164, 1327–1345, https://doi.org/10.1007/s00024-007-0221-8,
2007.
Van de Wiel, B. J. H., Moene, A. F., Steeneveld, G., Baas, P., Bosveld, F., and
Holtslag, A. A. M.: Intermittent Turbulence and Oscillations in the Stable
Boundary Layer over Land, Part III: A classification for observations during
CASES-99, J. Atmos. Sci., 60, 2509–2522,
https://doi.org/10.1175/1520-0469(2002)059<2567:ITAOIT>2.0.CO;2, 2003.
Van de Wiel, B. J. H., Moene, A. F., and Jonker, H. J. J.: The Cessation of
Continuous Turbulence as Precursor of the Very Stable Nocturnal Boundary
Layer, J. Atmos. Sci., 69, 3097–3115,
https://doi.org/10.1175/JAS-D-12-064.1, 2012a.
Van de Wiel, B. J. H., Moene, A. F., Jonker, H. J. J., Baas, P., Basu, S.,
Donda, J. M. M., Sun, J., and Holtslag, A. A. M.: The Minimum Wind Speed for
Sustainable Turbulence in the Nocturnal Boundary Layer, J. Atmos. Sci., 69,
3116–3127, https://doi.org/10.1175/JAS-D-12-0107.1, 2012b.
Van der Linden, S. J. A., Baas, P., Antoon van Hooft, J., van Hooijdonk, I.
G. S., Bosveld, F. C., and van de Wiel, B. J. H.: Local Characteristics of
the Nocturnal Boundary Layer in Response to External Pressure Forcing, J.
Appl. Meteorol. Clim., 56, 3035–3047,
https://doi.org/10.1175/JAMC-D-17-0011.1, 2017.
Van Hooijdonk, I. G. S., Donda, J. M. M., Clercx, H. J. H., Bosveld, F. C., and
van de Wiel, B. J. H.: Shear Capacity as Prognostic for Nocturnal Boundary
Layer Regimes, J. Atmos. Sci., 72, 1518–1532,
https://doi.org/10.1175/JAS-D-14-0140.1, 2015.
Webb, E. K., Pearman, G. I., and Leuning, R.: Correction of flux measurements
for density effects due to heat and water vapour transfer, Q. J. Roy. Meteorol.
Soc., 106, 85–100, https://doi.org/10.1002/qj.49710644707,
1980.
Whiteman, C.: Mountain Meteorology: Fundamentals and Applications, Oxford
University Press, Oxford, 2000.
Whiteman, C. D.: Breakup of Temperature Inversions in Deep Mountain Valleys:
Part I. Observations, J. Appl. Meteorol., 21, 270–289,
https://doi.org/10.1175/1520-0450(1982)021<0270:BOTIID>2.0.CO;2, 1982.
Zardi, D. and Whiteman, C.: Mountain Weather Research and Forecasting: Recent
Progress and Current Challenges, 1 edn., vol. XIII of Springer Atmospheric
Sciences, in: Diurnal Mountain WInd Systems, 35–119, Springer,
Netherlands, 2013.
Zhou, F.-H., Zhang, R.-W., Shi, R., Chen, J., He, Y.-K., and Xie, Q.:
Processing of Turbulent Data and Flux Quality Control of Observed Data from
Yongxing Island in Spring 2016, J. Coast. Res., 84, 114–124,
https://doi.org/10.2112/SI84-017.1, 2018.
Short summary
Thermally driven downslope winds develop in mountainous areas under a weak large-scale forcing and clear skies. In this work, we find that their onset time and intensity are closely connected with both the large-scale wind and soil moisture. We also show how the distinct downslope intensities shape the turbulent and thermal features of the nocturnal atmosphere. The analysis concludes that the downslope–turbulence interaction and the horizontal transport explain the important CO2 variability.
Thermally driven downslope winds develop in mountainous areas under a weak large-scale forcing...
Altmetrics
Final-revised paper
Preprint