Articles | Volume 24, issue 17
https://doi.org/10.5194/acp-24-10055-2024
© Author(s) 2024. 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-24-10055-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Sep 2024
Research article |
| 12 Sep 2024
| 12 Sep 2024
Relative humidity over ice as a key variable for Northern Hemisphere midlatitude tropopause inversion layers
Daniel Köhler
Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, Mainz, Germany
now at: Institute for Atmospheric and Earth System Research, University of Helsinki, Helsinki, Finland
Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, Mainz, Germany
Peter Spichtinger
Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, Mainz, Germany
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Tim Lüttmer, Peter Spichtinger, and Axel Seifert
EGUsphere, https://doi.org/10.5194/egusphere-2024-2157, https://doi.org/10.5194/egusphere-2024-2157, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We investigate ice formation pathways in idealized convective clouds using a novel microphysics scheme, that distinguishes between five ice classes each with their unique formation mechanism. Ice crystals from rime splintering forms the lowermost layer of ice crystals around the updraft core. The majority of ice crystals in the anvil of the convective cloud stems from frozen droplets. Ice stemming from homogeneous and deposition nucleation was only relevant in the overshoot.
Hans-Christoph Lachnitt, Peter Hoor, Daniel Kunkel, Martina Bramberger, Andreas Dörnbrack, Stefan Müller, Philipp Reutter, Andreas Giez, Thorsten Kaluza, and Markus Rapp
Atmos. Chem. Phys., 23, 355–373, https://doi.org/10.5194/acp-23-355-2023, https://doi.org/10.5194/acp-23-355-2023, 2023
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We present an analysis of high-resolution airborne measurements during a flight of the DEEPWAVE 2014 campaign in New Zealand. The focus of this flight was to study the effects of enhanced mountain wave activity over the Southern Alps. We discuss changes in the upstream and downstream distributions of N2O and CO and show that these changes are related to turbulence-induced trace gas fluxes which have persistent effects on the trace gas composition in the lower stratosphere.
Stefan Niebler, Annette Miltenberger, Bertil Schmidt, and Peter Spichtinger
Weather Clim. Dynam., 3, 113–137, https://doi.org/10.5194/wcd-3-113-2022, https://doi.org/10.5194/wcd-3-113-2022, 2022
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We use machine learning to create a network that detects and classifies four types of synoptic-scale weather fronts from ERA5 atmospheric reanalysis data. We present an application of our method, showing its use case in a scientific context. Additionally, our results show that multiple sources of training data are necessary to perform well on different regions, implying differences within those regions. Qualitative evaluation shows that the results are physically plausible.
Manuel Baumgartner, Christian Rolf, Jens-Uwe Grooß, Julia Schneider, Tobias Schorr, Ottmar Möhler, Peter Spichtinger, and Martina Krämer
Atmos. Chem. Phys., 22, 65–91, https://doi.org/10.5194/acp-22-65-2022, https://doi.org/10.5194/acp-22-65-2022, 2022
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An important mechanism for the appearance of ice particles in the upper troposphere at low temperatures is homogeneous nucleation. This process is commonly described by the
Koop line, predicting the humidity at freezing. However, laboratory measurements suggest that the freezing humidities are above the Koop line, motivating the present study to investigate the influence of different physical parameterizations on the homogeneous freezing with the help of a detailed numerical model.
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Martina Krämer, Peter Spichtinger, Nicole Spelten, Armin Afchine, Christian Rolf, Silvia Viciani, Francesco D'Amato, Holger Tost, and Stephan Borrmann
Atmos. Chem. Phys., 21, 13455–13481, https://doi.org/10.5194/acp-21-13455-2021, https://doi.org/10.5194/acp-21-13455-2021, 2021
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In July and August 2017, the StratoClim mission took place in Nepal with eight flights of the M-55 Geophysica at up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) next to cloud ice was detected in situ by abundant nucleation-mode aerosols (> 6 nm) along with ice particles (> 3 µm). NPF was observed mainly below the tropopause, down to 15 % being non-volatile residues. Observed intra-cloud NPF indicates its importance for the composition in the tropical tropopause layer.
Manuel Baumgartner, Ralf Weigel, Allan H. Harvey, Felix Plöger, Ulrich Achatz, and Peter Spichtinger
Atmos. Chem. Phys., 20, 15585–15616, https://doi.org/10.5194/acp-20-15585-2020, https://doi.org/10.5194/acp-20-15585-2020, 2020
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The potential temperature is routinely used in atmospheric science. We review its derivation and suggest a new potential temperature, based on a temperature-dependent parameterization of the dry air's specific heat capacity. Moreover, we compare the new potential temperature to the common one and discuss the differences which become more important at higher altitudes. Finally, we indicate some consequences of using the new potential temperature in typical applications.
Martina Krämer, Christian Rolf, Nicole Spelten, Armin Afchine, David Fahey, Eric Jensen, Sergey Khaykin, Thomas Kuhn, Paul Lawson, Alexey Lykov, Laura L. Pan, Martin Riese, Andrew Rollins, Fred Stroh, Troy Thornberry, Veronika Wolf, Sarah Woods, Peter Spichtinger, Johannes Quaas, and Odran Sourdeval
Atmos. Chem. Phys., 20, 12569–12608, https://doi.org/10.5194/acp-20-12569-2020, https://doi.org/10.5194/acp-20-12569-2020, 2020
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To improve the representations of cirrus clouds in climate predictions, extended knowledge of their properties and geographical distribution is required. This study presents extensive airborne in situ and satellite remote sensing climatologies of cirrus and humidity, which serve as a guide to cirrus clouds. Further, exemplary radiative characteristics of cirrus types and also in situ observations of tropical tropopause layer cirrus and humidity in the Asian monsoon anticyclone are shown.
Andreas Petzold, Patrick Neis, Mihal Rütimann, Susanne Rohs, Florian Berkes, Herman G. J. Smit, Martina Krämer, Nicole Spelten, Peter Spichtinger, Philippe Nédélec, and Andreas Wahner
Atmos. Chem. Phys., 20, 8157–8179, https://doi.org/10.5194/acp-20-8157-2020, https://doi.org/10.5194/acp-20-8157-2020, 2020
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The first analysis of 15 years of global-scale water vapour and relative humidity observations by passenger aircraft in the MOZAIC and IAGOS programmes resolves detailed features of water vapour and ice-supersaturated air in the mid-latitude tropopause. Key results provide in-depth insight into seasonal and regional variability and chemical signatures of ice-supersaturated air masses, including trend analyses, and show a close link to cirrus clouds and their highly important effects on climate.
Philipp Reutter, Patrick Neis, Susanne Rohs, and Bastien Sauvage
Atmos. Chem. Phys., 20, 787–804, https://doi.org/10.5194/acp-20-787-2020, https://doi.org/10.5194/acp-20-787-2020, 2020
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This study compares in situ measurements of temperature and humidity in the upper troposphere and lower stratosphere with reanalysis data from the ECMWF ERA-Interim data set. It is shown that temperature compares well between both data sets. However, extreme values of relative humidity with respect to ice (RHi) are missing in ERA-Interim, and hence the number and size of ice supersaturated regions differ strongly between both data sets.
Manuel Baumgartner, Max Sagebaum, Nicolas R. Gauger, Peter Spichtinger, and André Brinkmann
Geosci. Model Dev., 12, 5197–5212, https://doi.org/10.5194/gmd-12-5197-2019, https://doi.org/10.5194/gmd-12-5197-2019, 2019
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Numerical models in atmospheric sciences need to include physical processes through parameterizations, which are not explicitly resolved, e.g., the formation of clouds. As a consequence, the parameterizations contain uncertain parameters. We suggest using the technique of algorithmic differentiation (AD) to identify the most uncertain parameters within parameterizations. In this study, we illustrate AD by analyzing a scheme for liquid clouds incorporated into a parcel model framework.
Manuel Baumgartner and Peter Spichtinger
Atmos. Chem. Phys., 18, 2525–2546, https://doi.org/10.5194/acp-18-2525-2018, https://doi.org/10.5194/acp-18-2525-2018, 2018
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Ice crystals are surrounded by liquid cloud droplets in mixed-phase clouds. The coexistence of ice and water is thermodynamically not stable and the particles will influence their respective growth by condensation. This effect is known as the Wegener–Bergeron–Findeisen process. In current models, the local interactions of the particles are neglected and they can only interact indirectly. This work proposes an approach to include local interactions and discusses some implications.
Qing Mu, Gerhard Lammel, Christian N. Gencarelli, Ian M. Hedgecock, Ying Chen, Petra Přibylová, Monique Teich, Yuxuan Zhang, Guangjie Zheng, Dominik van Pinxteren, Qiang Zhang, Hartmut Herrmann, Manabu Shiraiwa, Peter Spichtinger, Hang Su, Ulrich Pöschl, and Yafang Cheng
Atmos. Chem. Phys., 17, 12253–12267, https://doi.org/10.5194/acp-17-12253-2017, https://doi.org/10.5194/acp-17-12253-2017, 2017
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Polycyclic aromatic hydrocarbons (PAHs) are hazardous pollutants with the largest emissions in East Asia. The regional WRF-Chem-PAH model has been developed to reflect the state-of-the-art understanding of current PAHs studies with several new or updated features. It is able to reasonably well simulate the concentration levels and particulate mass fractions of PAHs near the sources and at a remote outflow region of East Asia, in high spatial and temporal resolutions.
Marcus Klingebiel, André Ehrlich, Fanny Finger, Timo Röschenthaler, Suad Jakirlić, Matthias Voigt, Stefan Müller, Rolf Maser, Manfred Wendisch, Peter Hoor, Peter Spichtinger, and Stephan Borrmann
Atmos. Meas. Tech., 10, 3485–3498, https://doi.org/10.5194/amt-10-3485-2017, https://doi.org/10.5194/amt-10-3485-2017, 2017
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Microphysical and radiation measurements were collected with the unique AIRcraft TOwed Sensor Shuttle (AIRTOSS) – Learjet tandem platform. It is a combination of a Learjet 35A research aircraft and an instrumented aerodynamic bird, which can be detached from and retracted back to the aircraft during flight.
AIRTOSS and Learjet are equipped with radiative, cloud microphysical, trace gas,
and meteorological instruments to study cirrus clouds.
Elisa Johanna Spreitzer, Manuel Patrik Marschalik, and Peter Spichtinger
Nonlin. Processes Geophys., 24, 307–328, https://doi.org/10.5194/npg-24-307-2017, https://doi.org/10.5194/npg-24-307-2017, 2017
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We developed a simple analytical model for describing subvisible cirrus clouds qualitatively. Using theory of dynamical systems we found two different states for the long-term behaviour of subvisible cirrus clouds, i.e. an attractor case (stable equilibrium point) and a limit cycle scenario. The transition between the states constitutes a Hopf bifurcation and is determined by environmental conditions such as vertical updraughts and temperature.
Thomas Berkemeier, Markus Ammann, Ulrich K. Krieger, Thomas Peter, Peter Spichtinger, Ulrich Pöschl, Manabu Shiraiwa, and Andrew J. Huisman
Atmos. Chem. Phys., 17, 8021–8029, https://doi.org/10.5194/acp-17-8021-2017, https://doi.org/10.5194/acp-17-8021-2017, 2017
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Kinetic process models are efficient tools used to unravel the mechanisms governing chemical and physical transformation in multiphase atmospheric chemistry. However, determination of kinetic parameters such as reaction rate or diffusion coefficients from multiple data sets is often difficult or ambiguous. This study presents a novel optimization algorithm and framework to determine these parameters in an automated fashion and to gain information about parameter uncertainty and uniqueness.
Ralf Weigel, Peter Spichtinger, Christoph Mahnke, Marcus Klingebiel, Armin Afchine, Andreas Petzold, Martina Krämer, Anja Costa, Sergej Molleker, Philipp Reutter, Miklós Szakáll, Max Port, Lucas Grulich, Tina Jurkat, Andreas Minikin, and Stephan Borrmann
Atmos. Meas. Tech., 9, 5135–5162, https://doi.org/10.5194/amt-9-5135-2016, https://doi.org/10.5194/amt-9-5135-2016, 2016
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The subject of our study concerns measurements with optical array probes (OAPs) on fast-flying aircraft such as the G550 (HALO or HIAPER). At up to Mach 0.7 the effect of air compression upstream of underwing-mounted instruments and particles' inertia need consideration for determining ambient particle concentrations. Compared to conventional practices the introduced correction procedure eliminates ambiguities and exhibits consistency over flight speeds between 50 and 250 m s−.
Fanny Finger, Frank Werner, Marcus Klingebiel, André Ehrlich, Evelyn Jäkel, Matthias Voigt, Stephan Borrmann, Peter Spichtinger, and Manfred Wendisch
Atmos. Chem. Phys., 16, 7681–7693, https://doi.org/10.5194/acp-16-7681-2016, https://doi.org/10.5194/acp-16-7681-2016, 2016
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Solar spectra of optical layer properties of cirrus have been derived from the first truly collocated airborne radiation measurements using an aircraft and a towed sensor platform. The measured layer properties differ slightly due to horizontal cirrus inhomogeneities and the influence of low-level water clouds. Applying a 1-D radiative transfer model sensitivity studies were performed. It was found that if a low-level cloud is not considered, the solar cooling of the cirrus is strongly overestimated.
P. Reutter, B. Škerlak, M. Sprenger, and H. Wernli
Atmos. Chem. Phys., 15, 10939–10953, https://doi.org/10.5194/acp-15-10939-2015, https://doi.org/10.5194/acp-15-10939-2015, 2015
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In this manuscript, we investigate the exchange of air masses across the dynamical tropopause (stratosphere-troposphere exchange, STE) in the vicinity of North Atlantic cyclones. By using two 6-hourly resolved ERA-Interim climatologies of STE and cyclones from 1979 to 2011, we are able to directly compute the amount of STE in the vicinity of every individual cyclone in this time period. This enables us to provide a robust and consistent quantification of STE near North Atlantic cyclones.
D. Chang, Y. Cheng, P. Reutter, J. Trentmann, S. M. Burrows, P. Spichtinger, S. Nordmann, M. O. Andreae, U. Pöschl, and H. Su
Atmos. Chem. Phys., 15, 10325–10348, https://doi.org/10.5194/acp-15-10325-2015, https://doi.org/10.5194/acp-15-10325-2015, 2015
P. Reutter, J. Trentmann, A. Seifert, P. Neis, H. Su, D. Chang, M. Herzog, H. Wernli, M. O. Andreae, and U. Pöschl
Atmos. Chem. Phys., 14, 7573–7583, https://doi.org/10.5194/acp-14-7573-2014, https://doi.org/10.5194/acp-14-7573-2014, 2014
A. Cirisan, B. P. Luo, I. Engel, F. G. Wienhold, M. Sprenger, U. K. Krieger, U. Weers, G. Romanens, G. Levrat, P. Jeannet, D. Ruffieux, R. Philipona, B. Calpini, P. Spichtinger, and T. Peter
Atmos. Chem. Phys., 14, 7341–7365, https://doi.org/10.5194/acp-14-7341-2014, https://doi.org/10.5194/acp-14-7341-2014, 2014
H. Joos, P. Spichtinger, P. Reutter, and F. Fusina
Atmos. Chem. Phys., 14, 6835–6852, https://doi.org/10.5194/acp-14-6835-2014, https://doi.org/10.5194/acp-14-6835-2014, 2014
P. Spichtinger and M. Krämer
Atmos. Chem. Phys., 13, 9801–9818, https://doi.org/10.5194/acp-13-9801-2013, https://doi.org/10.5194/acp-13-9801-2013, 2013
E. Kienast-Sjögren, P. Spichtinger, and K. Gierens
Atmos. Chem. Phys., 13, 9021–9037, https://doi.org/10.5194/acp-13-9021-2013, https://doi.org/10.5194/acp-13-9021-2013, 2013
Related subject area
Subject: Climate and Earth System | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Technical note: Posterior uncertainty estimation via a Monte Carlo procedure specialized for 4D-Var data assimilation
Understanding the role of contrails and contrail cirrus in climate change: a global perspective
Interannual variations in Siberian carbon uptake and carbon release period
Using historical temperature to constrain the climate sensitivity, the transient climate response, and aerosol-induced cooling
Future reduction of cold extremes over East Asia due to thermodynamic and dynamic warming
General circulation models simulate negative liquid water path–droplet number correlations, but anthropogenic aerosols still increase simulated liquid water path
Global scenarios of anthropogenic mercury emissions
Impact of Asian aerosols on the summer monsoon strongly modulated by regional precipitation biases
Opinion: Optimizing climate models with process knowledge, resolution, and artificial intelligence
Assessing methane emissions from collapsing Venezuelan oil production using TROPOMI
Impacts of tropical cyclone-heatwave compound events on surface ozone in eastern China: Comparison between the Yangtze River and Pearl River Deltas
Present-Day Methane Shortwave Absorption Mutes Surface Warming and Wetting Relative to Preindustrial Conditions
Parameterizations for global thundercloud corona discharge distributions
Simulation of ozone–vegetation coupling and feedback in China using multiple ozone damage schemes
A novel method to detect the tropopause structure based on bi-Gaussian function
Multi-scale variability of southeast Australian wind resources
Opinion: Can uncertainty in climate sensitivity be narrowed further?
Increasing Aerosol Direct Effect Despite Declining Global Emissions in MPI-ESM1.2
Unravelling Disparities in Eulerian and Lagrangian Moisture Tracking Models in Monsoon- and Westerlies-dominated Basins Around the Tibetan Plateau
Significant human health co-benefits of mitigating African emissions
Water vapour exchange between the atmospheric boundary layer and free troposphere over eastern China: seasonal characteristics and the El Niño–Southern Oscillation anomaly
Strong aerosol cooling alone does not explain cold-biased mid-century temperatures in CMIP6 models
Investigation of the climatology of low-level jets over North America in a high-resolution WRF simulation
Air pollution reductions caused by the COVID-19 lockdown open up a way to preserve the Himalayan glaciers
Modeling atmosphere–land interactions at a rainforest site – a case study using Amazon Tall Tower Observatory (ATTO) measurements and reanalysis data
Michael Stanley, Mikael Kuusela, Brendan Byrne, and Junjie Liu
Atmos. Chem. Phys., 24, 9419–9433, https://doi.org/10.5194/acp-24-9419-2024, https://doi.org/10.5194/acp-24-9419-2024, 2024
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To serve the uncertainty quantification (UQ) needs of 4D-Var data assimilation (DA) practitioners, we describe and justify a UQ algorithm from carbon flux inversion and incorporate its sampling uncertainty into the final reported UQ. The algorithm is mathematically proved, and its performance is shown for a carbon flux observing system simulation experiment. These results legitimize and generalize this algorithm's current use and make available this effective algorithm to new DA domains.
Dharmendra Kumar Singh, Swarnali Sanyal, and Donald J. Wuebbles
Atmos. Chem. Phys., 24, 9219–9262, https://doi.org/10.5194/acp-24-9219-2024, https://doi.org/10.5194/acp-24-9219-2024, 2024
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Radiative forcing of contrails could triple by 2050 due to increased air traffic and potential changes in flight altitudes. Factors like air traffic patterns, fuel efficiency, alternative fuels, and climate change further influence this impact. By highlighting gaps in knowledge and uncertainties, this research helps set priorities for future studies and assess strategies to mitigate the environmental impact of aviation emissions.
Dieu Anh Tran, Christoph Gerbig, Christian Rödenbeck, and Sönke Zaehle
Atmos. Chem. Phys., 24, 8413–8440, https://doi.org/10.5194/acp-24-8413-2024, https://doi.org/10.5194/acp-24-8413-2024, 2024
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The analysis of the atmospheric CO2 record from the Zotino Tall Tower Observatory (ZOTTO) in central Siberia shows significant increases in the length and amplitude of the CO2 uptake and release in the 2010–2021 period. The trend shows a stronger increase in carbon release amplitude compared to the uptake, suggesting that, despite enhanced growing season uptake, during this period climate warming did not elevate the annual net CO2 uptake as cold-season respirations also responded to the warming.
Olaf Morgenstern
Atmos. Chem. Phys., 24, 8105–8123, https://doi.org/10.5194/acp-24-8105-2024, https://doi.org/10.5194/acp-24-8105-2024, 2024
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I use errors in climate model simulations to derive correction factors for the impacts of greenhouse gases and particles that bring these simulated temperature fields into agreement with an observational reconstruction of the Earth's temperature. On average across eight models, a reduction by about one-half of the particle-induced cooling would be required, causing only 0.24 K of cooling since 1850–1899. The greenhouse gas warming simulated by several highly sensitive models would also reduce.
Donghuan Li, Tianjun Zhou, Youcun Qi, Liwei Zou, Chao Li, Wenxia Zhang, and Xiaolong Chen
Atmos. Chem. Phys., 24, 7347–7358, https://doi.org/10.5194/acp-24-7347-2024, https://doi.org/10.5194/acp-24-7347-2024, 2024
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Two sets of climate model simulations are used to investigate the dynamic and thermodynamic factors of future change in cold extremes in East Asia. Dynamic factor accounted for over 80 % of cold-month temperature anomalies in past 50 years. The intensity of cold extreme is expected to decrease by 5 ℃, with thermodynamic factor contributing ~ 75 % by the end of the 21st century. Changes in dynamic factor are driven by an upward trend of positive Arctic Oscillation-like sea level pressure pattern.
Johannes Mülmenstädt, Edward Gryspeerdt, Sudhakar Dipu, Johannes Quaas, Andrew S. Ackerman, Ann M. Fridlind, Florian Tornow, Susanne E. Bauer, Andrew Gettelman, Yi Ming, Youtong Zheng, Po-Lun Ma, Hailong Wang, Kai Zhang, Matthew W. Christensen, Adam C. Varble, L. Ruby Leung, Xiaohong Liu, David Neubauer, Daniel G. Partridge, Philip Stier, and Toshihiko Takemura
Atmos. Chem. Phys., 24, 7331–7345, https://doi.org/10.5194/acp-24-7331-2024, https://doi.org/10.5194/acp-24-7331-2024, 2024
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Human activities release copious amounts of small particles called aerosols into the atmosphere. These particles change how much sunlight clouds reflect to space, an important human perturbation of the climate, whose magnitude is highly uncertain. We found that the latest climate models show a negative correlation but a positive causal relationship between aerosols and cloud water. This means we need to be very careful when we interpret observational studies that can only see correlation.
Flora Maria Brocza, Peter Rafaj, Robert Sander, Fabian Wagner, and Jenny Marie Jones
Atmos. Chem. Phys., 24, 7385–7404, https://doi.org/10.5194/acp-24-7385-2024, https://doi.org/10.5194/acp-24-7385-2024, 2024
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To understand how atmospheric mercury levels will change in the future, we model how anthropogenic Hg releases will change following developments in human energy use and mercury use and efforts to reduce pollution and battle climate change. Overall, the findings emphasize that it will be necessary to implement targeted Hg control measures in addition to stringent climate and clean air policies to achieve significant reductions in Hg emissions.
Zhen Liu, Massimo A. Bollasina, and Laura J. Wilcox
Atmos. Chem. Phys., 24, 7227–7252, https://doi.org/10.5194/acp-24-7227-2024, https://doi.org/10.5194/acp-24-7227-2024, 2024
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The aerosol impact on monsoon precipitation and circulation is strongly influenced by a model-simulated spatio-temporal variability in the climatological monsoon precipitation across Asia, which critically modulates the efficacy of aerosol–cloud–precipitation interactions, the predominant driver of the total aerosol response. There is a strong interplay between South Asia and East Asia monsoon precipitation biases and their relative predominance in driving the overall monsoon response.
Tapio Schneider, L. Ruby Leung, and Robert C. J. Wills
Atmos. Chem. Phys., 24, 7041–7062, https://doi.org/10.5194/acp-24-7041-2024, https://doi.org/10.5194/acp-24-7041-2024, 2024
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Climate models are crucial for predicting climate change in detail. This paper proposes a balanced approach to improving their accuracy by combining traditional process-based methods with modern artificial intelligence (AI) techniques while maximizing the resolution to allow for ensemble simulations. The authors propose using AI to learn from both observational and simulated data while incorporating existing physical knowledge to reduce data demands and improve climate prediction reliability.
Brian Nathan, Joannes D. Maasakkers, Stijn Naus, Ritesh Gautam, Mark Omara, Daniel J. Varon, Melissa P. Sulprizio, Lucas A. Estrada, Alba Lorente, Tobias Borsdorff, Robert J. Parker, and Ilse Aben
Atmos. Chem. Phys., 24, 6845–6863, https://doi.org/10.5194/acp-24-6845-2024, https://doi.org/10.5194/acp-24-6845-2024, 2024
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Venezuela's Lake Maracaibo region is notoriously hard to observe from space and features intensive oil exploitation, although production has strongly decreased in recent years. We estimate methane emissions using 2018–2020 TROPOMI satellite observations with national and regional transport models. Despite the production decrease, we find relatively constant emissions from Lake Maracaibo between 2018 and 2020, indicating that there could be large emissions from abandoned infrastructure.
Cuini Qi, Pinya Wang, Yang Yang, Huimin Li, Hui Zhang, Lili Ren, Xipeng Jin, Chenchao Zhan, Jianping Tang, and Hong Liao
EGUsphere, https://doi.org/10.5194/egusphere-2024-846, https://doi.org/10.5194/egusphere-2024-846, 2024
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We investigate extreme hot weathers impacts on surface ozone over Southeastern Coast of China with (TC-HDs) and without (AHDs) tropical cyclones. Compared to AHDs, ozone concentration decreased notably in Yangtze River Delta (YRD) but increased in Pearl River Delta (PRD) during TC-HDs. YRD benefitted from strong, clean sea winds aiding ozone elimination. In contrast, PRD experienced strong northeasterly winds, potentially transporting ozone pollution.
Robert J. Allen, Xueying Zhao, Cynthia A. Randles, Ryan J. Kramer, Bjorn H. Samset, and Christopher J. Smith
EGUsphere, https://doi.org/10.5194/egusphere-2024-872, https://doi.org/10.5194/egusphere-2024-872, 2024
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Present-day methane shortwave absorption mutes 29 % of the surface warming and 66 % of the precipitation increase associated with its longwave absorption. The muting effect of present-day methane shortwave absorption is about five times larger as compared to that under idealized carbon dioxide perturbations.
Sergio Soler, Francisco J. Gordillo-Vázquez, Francisco J. Pérez-Invernón, Patrick Jöckel, Torsten Neubert, Olivier Chanrion, Victor Reglero, and Nikolai Østgaard
EGUsphere, https://doi.org/10.5194/egusphere-2024-132, https://doi.org/10.5194/egusphere-2024-132, 2024
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Sudden local ozone (O3) enhancements have been reported in different regions of the world since the 1970s. While the hot channel of lightning strokes directly produce significant amounts of nitrogen oxide, no direct emission of O3 is expected. Corona discharges in convectively active regions could explain local O3 increases, which remains unexplained. We present the first mathematical functions that relate the global annual frequency of in-cloud coronas with four sets of meteorological variables
Jiachen Cao, Xu Yue, and Mingrui Ma
Atmos. Chem. Phys., 24, 3973–3987, https://doi.org/10.5194/acp-24-3973-2024, https://doi.org/10.5194/acp-24-3973-2024, 2024
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We implemented two widely used ozone damage schemes into a same regional model. Although the two schemes yielded distinct ozone vegetation damages, they predicted similar feedbacks to surface air temperature and ozone air quality in China. Our results highlighted the significance of ozone pollution control given its detrimental impacts on ecosystem functions, contributions to global warming, and amplifications of ozone pollution through ozone–vegetation coupling.
Kun Zhang, Tao Luo, Xuebin Li, Shengcheng Cui, Ningquan Weng, Yinbo Huang, and Yingjian Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-345, https://doi.org/10.5194/egusphere-2024-345, 2024
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In order to deeply understand the formation mechanisms and evolution processes of vertical tropopause structures, this study proposes a new method to identify the multiple characteristic parameters of tropopause vertical structures, by mean of fitting the temperature profiles using the bi-Gaussian function.
Claire Louise Vincent and Andrew J. Dowdy
EGUsphere, https://doi.org/10.5194/egusphere-2024-228, https://doi.org/10.5194/egusphere-2024-228, 2024
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We investigated how wind speed at the height of a typical wind turbine changes during El Nino and La Nina years, and with season and time of day in southeast Australia. We found that El Niño and La Niña can cause average wind speed differences of around 1 m/s in some regions. The highest winds speeds occur in the afternoon or evening around mountains or the coast, and during the night inland. The results help show how strategic placement of wind turbines can balance electricity generation.
Steven C. Sherwood and Chris E. Forest
Atmos. Chem. Phys., 24, 2679–2686, https://doi.org/10.5194/acp-24-2679-2024, https://doi.org/10.5194/acp-24-2679-2024, 2024
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The most fundamental parameter used to gauge the severity of future climate change is the so-called equilibrium climate sensitivity, which measures the warming that would ultimately occur due to a doubling of atmospheric carbon dioxide levels. Due to recent advances it is now thought to probably lie in the range 2.5–4 °C. We discuss this and the issues involved in evaluating and using the number, pointing to some pitfalls in current efforts but also possibilities for further progress.
Antoine Hermant, Linnea Huusko, and Thorsten Mauritsen
EGUsphere, https://doi.org/10.22541/essoar.170158317.78990757/v1, https://doi.org/10.22541/essoar.170158317.78990757/v1, 2024
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Aerosol particles, from natural and human sources, have a cooling effect on the climate, partially offsetting global warming. They do this through direct (sunlight reflection) and indirect (cloud property alteration) mechanisms. Using a global climate model, we found that despite declining emissions, the direct effect of human-made aerosols has increased, while the indirect effect has decreased, attributed to the shift in emissions from North America and Europe to Southeast Asia.
Ying Li, Chenghao Wang, Qiuhong Tang, Shibo Yao, Bo Sun, Hui Peng, and Shangbin Xiao
EGUsphere, https://doi.org/10.5194/egusphere-2024-14, https://doi.org/10.5194/egusphere-2024-14, 2024
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This study compare the applications of the most widely used Eulerian (WAM-2layers) and Lagrangian (FLEXPART-WaterSip) models in the Tibetan Plateau. WAM-2layers is more effectively in identifying varying moisture contributions arising from distinct surface evaporation sources, while FLEXPART-WaterSip tend to be more reliable in regions heavily influenced by smaller-scale convective systems with high spatial heterogeneity.
Christopher D. Wells, Matthew Kasoar, Majid Ezzati, and Apostolos Voulgarakis
Atmos. Chem. Phys., 24, 1025–1039, https://doi.org/10.5194/acp-24-1025-2024, https://doi.org/10.5194/acp-24-1025-2024, 2024
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Human-driven emissions of air pollutants, mostly caused by burning fossil fuels, impact both the climate and human health. Millions of deaths each year are caused by air pollution globally, and the future trends are uncertain. Here, we use a global climate model to study the effect of African pollutant emissions on surface level air pollution, and resultant impacts on human health, in several future emission scenarios. We find much lower health impacts under cleaner, lower-emission futures.
Xipeng Jin, Xuhui Cai, Xuesong Wang, Qianqian Huang, Yu Song, Ling Kang, Hongsheng Zhang, and Tong Zhu
Atmos. Chem. Phys., 24, 259–274, https://doi.org/10.5194/acp-24-259-2024, https://doi.org/10.5194/acp-24-259-2024, 2024
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This work presents a climatology of water vapour exchange flux between the atmospheric boundary layer (ABL) and free troposphere (FT) over eastern China. The water vapour exchange maintains ABL humidity in cold months and moistens the FT in warm seasons, and its distribution has terrain-dependent features. The exchange flux is correlated with the El Niño–Southern Oscillation (ENSO) index and precipitation pattern. The study provides new insight into moisture transport and extreme weather.
Clare Marie Flynn, Linnea Huusko, Angshuman Modak, and Thorsten Mauritsen
Atmos. Chem. Phys., 23, 15121–15133, https://doi.org/10.5194/acp-23-15121-2023, https://doi.org/10.5194/acp-23-15121-2023, 2023
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The latest-generation climate models show surprisingly cold mid-20th century global-mean temperatures, often despite exhibiting more realistic late 20th/early 21st century temperatures. A too-strong aerosol forcing in many models was thought to the be primary cause of these too-cold mid-century temperatures, but this was found to only be a partial explanation. This also partly undermines the hope to construct a strong relationship between the mid-century temperatures and aerosol forcing.
Xiao Ma, Yanping Li, Zhenhua Li, and Fei Huo
EGUsphere, https://doi.org/10.5194/egusphere-2023-2342, https://doi.org/10.5194/egusphere-2023-2342, 2023
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This research studies the climatological attributes of low-level jets (LLJs) across North America using a 4km simulation. The study identifies significant LLJ systems such as the Great Plains LLJs. It also provides insights into less adequately represented LLJ systems by coarser models, such as the Quebec Northerly LLJ and small-scale low-level wind maxima around the Rocky Mountains. Additionally, the study investigates three distinct LLJs' diverse physical mechanisms driving their formation.
Suvarna Fadnavis, Bernd Heinold, T. P. Sabin, Anne Kubin, Katty Huang, Alexandru Rap, and Rolf Müller
Atmos. Chem. Phys., 23, 10439–10449, https://doi.org/10.5194/acp-23-10439-2023, https://doi.org/10.5194/acp-23-10439-2023, 2023
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The influence of the COVID-19 lockdown on the Himalayas caused increases in snow cover and a decrease in runoff, ultimately leading to an enhanced snow water equivalent. Our findings highlight that, out of the two processes causing a retreat of Himalayan glaciers – (1) slow response to global climate change and (2) fast response to local air pollution – a policy action on the latter is more likely to be within the reach of possible policy action to help billions of people in southern Asia.
Amelie U. Schmitt, Felix Ament, Alessandro C. de Araújo, Marta Sá, and Paulo Teixeira
Atmos. Chem. Phys., 23, 9323–9346, https://doi.org/10.5194/acp-23-9323-2023, https://doi.org/10.5194/acp-23-9323-2023, 2023
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Tall vegetation in forests affects the exchange of heat and moisture between the atmosphere and the land surface. We compared measurements from the Amazon Tall Tower Observatory to results from a land surface model to identify model shortcomings. Our results suggest that soil temperatures in the model could be improved by incorporating a separate canopy layer which represents the heat storage within the forest.
Cited articles
Baumgartner, M., Weigel, R., Harvey, A. H., Plöger, F., Achatz, U., and Spichtinger, P.: Reappraising the appropriate calculation of a common meteorological quantity: potential temperature, Atmos. Chem. Phys., 20, 15585–15616, https://doi.org/10.5194/acp-20-15585-2020, 2020. a
Bethan, S., Vaughan, G., and Reid, S.: A comparison of ozone and thermal tropopause heights and the impact of tropopause definition on quantifying the ozone content of the troposphere, Q. J. Roy. Meteor. Soc., 122, 929–944, https://doi.org/10.1002/qj.49712253207, 1996. a
Birner, T.: Fine‐scale structure of the extratropical tropopause region, J. Geophys. Res., 111, D04104, https://doi.org/10.1029/2005JD006301, 2006. a, b, c
Birner, T.: Residual Circulation and Tropopause Structure, J. Atmos. Sci., 67, 2582–2600, https://doi.org/10.1175/2010JAS3287.1, 2010. a
Birner, T., Dörnbrack, A., and Schumann, U.: How sharp is the tropopause at midlatitudes?, Geophys. Res. Lett., 29, 45-1–45-4, https://doi.org/10.1029/2002GL015142, 2002. a, b, c, d
Durran, D. R. and Klemp, J. B.: On the Effects of Moisture on the Brunt-Väisälä Frequency, J. Atmos. Sci., 39, https://doi.org/10.1175/1520-0469(1982)039<2152:OTEOMO>2.0.CO;2, 1982. a
DWD: Radiosonde data, DWD [data set], https://opendata.dwd.de/climate_environment/CDC/observations_germany/radiosondes/high_resolution/historical/, last access: 5 September 2024. a
Erler, A. R. and Wirth, V.: The Static Stability of the Tropopause Region in Adiabatic Baroclinic Life Cycle Experiments, J. Atmos. Sci., 68, 1178–1193, https://doi.org/10.1175/2010JAS3694.1, 2011. a
Fusina, F. and Spichtinger, P.: Cirrus clouds triggered by radiation, a multiscale phenomenon, Atmos. Chem. Phys., 10, 5179–5190, https://doi.org/10.5194/acp-10-5179-2010, 2010. a, b, c
Gettelman, A. and Wang, T.: Structural diagnostics of the tropopause inversion layer and its evolution, J. Geophys. Res., 120, 46–62, https://doi.org/10.1002/2014JD021846, 2015. a, b
Gettelman, A., Hoor, P., Pan, L. L., Randel, W. J., Hegglin, M. I., and Birner, T.: The Extratropical Upper Troposphere and Lower Stratosphere, Rev. Geophys., 49, RG3003, https://doi.org/10.1029/2011RG000355, 2011. a, b, c
Gierens, K., Schumann, U., Helten, M., Smit, H., and Marenco, A.: A distribution law for relative humidity in the upper troposphere and lower stratosphere derived from three years of MOZAIC measurements, Ann. Geophys., 17, 1218–1226, https://doi.org/10.1007/s00585-999-1218-7, 1999. a
Grise, K. M., Thompson, D. W. J., and Birner, T.: A Global Survey of Static Stability in the Stratosphere and Upper Troposphere, J. Climate, 23, 2275–2292, https://doi.org/10.1175/2009JCLI3369.1, 2010. a
Hantel, M.: Einführung Theoretische Meteorologie, Vol. 1, Springer Spektrum, Springer-Verlag Berlin Heidelberg, 1st Edn., ISBN 978-3-8274-3055-7, https://doi.org/10.1007/978-3-8274-3056-4, 2013. a
Hegglin, M. I., Boone, C., Manney, G. L., and Walker, K. A.: A global view of the extratropical tropopause transition layer from Atmospheric Chemistry Experiment Fourier Transform Spectrometer O3, H2O, and CO, J. Geophys. Res.-Atmos., 114, D00B11, https://doi.org/10.1029/2008JD009984, 2009. a
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz‐Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.: The ERA5 global reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020. a, b, c
Hersbach, H., Bell, B., Berrisford, P., Biavati, G., Horányi, A., Muñoz Sabater, J., Nicolas, J., Peubey, C., Radu, R., Rozum, I., Schepers, D., Simmons, A., Soci, C., Dee, D., and Thépaut, J.-N.: ERA5 hourly data on single levels from 1940 to present, Copernicus Climate Change Service (C3S) Climate Data Store (CDS) [data set], https://doi.org/10.24381/cds.adbb2d47, 2023. a
Highwood, E. J. and Hoskins, B. J.: The tropical tropopause, Q. J. Roy. Meteor. Soc., 124, 1579–1604, https://doi.org/10.1002/qj.49712454911, 1998. a
Hoerling, M. P., Schaack, T. K., and Lenzen, A. J.: Global Objective Tropopause Analysis, Mon. Weather Rev., 119, 1816–1831, https://doi.org/10.1175/1520-0493(1991)119<1816:GOTA>2.0.CO;2, 1991. a
Hoffmann, L. and Spang, R.: An assessment of tropopause characteristics of the ERA5 and ERA-Interim meteorological reanalyses, Atmos. Chem. Phys., 22, 4019–4046, https://doi.org/10.5194/acp-22-4019-2022, 2022. a
Hoinka, K.: The tropopause: discovery, definition and demarcation, Meteorol. Z., 6, 281–303, https://doi.org/10.1127/metz/6/1997/281, 1997. a
Hoinka, K.: Statistics of the global tropopause pressure, Mon. Weather Rev., 126, 3303–3325, https://doi.org/10.1175/1520-0493(1998)126<3303:SOTGTP>2.0.CO;2, 1998. a
Hoskins, B. J. and James, I. N.: Fluid Dynamics of the Midlatitude Atmosphere, Wiley, 1st Edn., ISBN 978-0-470-83369-8, 978-1-118-52600-2, https://doi.org/10.1002/9781118526002, 2014. a
Köhler, D.: Code for “The extratropical tropopause inversion layer and its correlation with relative humidity”, Zenodo [code], https://doi.org/10.5281/zenodo.10604349, 2024. a, b
Kunz, A., Konopka, P., Müller, R., Pan, L. L., Schiller, C., and Rohrer, F.: High static stability in the mixing layer above the extratropical tropopause, J. Geophys. Res.-Atmospheres, 114, D16305, https://doi.org/10.1029/2009JD011840, 2009. a
Kunz, A., Konopka, P., Mueller, R., and Pan, L. L.: Dynamical tropopause based on isentropic potential vorticity gradients, J. Geophys. Res., 116, D01110, https://doi.org/10.1029/2010JD014343, 2011. a, b
Maddox, E. M. and Mullendore, G. L.: Determination of Best Tropopause Definition for Convective Transport Studies, J. Atmos. Sci., 75, 3433–3446, https://doi.org/10.1175/JAS-D-18-0032.1, 2018. a, b
Miloshevich, L. M., Paukkunen, A., Vömel, H., and Oltmans, S. J.: Development and Validation of a Time-Lag Correction for Vaisala Radiosonde Humidity Measurements, J. Atmos. Ocean. Tech., 21, 1305–1327, https://doi.org/10.1175/1520-0426(2004)021<1305:DAVOAT>2.0.CO;2, 2004. a
Miloshevich, L. M., Vömel, H., Whiteman, D. N., and Leblanc, T.: Accuracy assessment and correction of Vaisala RS92 radiosonde water vapor measurements, J. Geophys. Res.-Atmos., 114, D11305, https://doi.org/10.1029/2008JD011565, 2009. a
Mullendore, G., Durran, D., and Holton, J.: Cross-tropopause tracer transport in midlatitude convection, J. Geophys. Res., 110, D06113, https://doi.org/10.1029/2004JD005059, 2005. a
Murphy, D. M. and Koop, T.: Review of the vapour pressures of ice and supercooled water for atmospheric applications, Q. J. Roy. Meteor. Soc., 131, 1539–1565, https://doi.org/10.1256/qj.04.94, 2005. a
Niebler, S., Miltenberger, A., Schmidt, B., and Spichtinger, P.: Automated detection and classification of synoptic-scale fronts from atmospheric data grids, Weather Clim. Dynam., 3, 113–137, https://doi.org/10.5194/wcd-3-113-2022, 2022. a
Pan, L., Randel, W., Gary, B., Mahoney, M., and Hintsa, E.: Definitions and sharpness of the extratropical tropopause: A trace gas perspective, J. Geophys. Res., 109, D23103, https://doi.org/10.1029/2004JD004982, 2004. a
Peters, J. M., Mulholland, J. P., and Chavas, D. R.: Generalized Lapse Rate Formulas for Use in Entraining CAPE Calculations, J. Atmos. Sci., 79, 815–836, https://doi.org/10.1175/JAS-D-21-0118.1, 2022. a
Randel, W. J. and Wu, F.: The Polar Summer Tropopause Inversion Layer, J. Atmos. Sci., 67, 2572–2581, https://doi.org/10.1175/2010JAS3430.1, 2010. a
Reichler, T., Dameris, M., and Sausen, R.: Determining the tropopause height from gridded data, Geophys. Res. Lett., 30, 2042, https://doi.org/10.1029/2003GL018240, 2003. a
Reutter, P., Neis, P., Rohs, S., and Sauvage, B.: Ice supersaturated regions: properties and validation of ERA-Interim reanalysis with IAGOS in situ water vapour measurements, Atmos. Chem. Phys., 20, 787–804, https://doi.org/10.5194/acp-20-787-2020, 2020. a
Schmidt, T., Cammas, J.-P., Smit, H. G. J., Heise, S., Wickert, J., and Haser, A.: Observational characteristics of the tropopause inversion layer derived from CHAMP/GRACE radio occultations and MOZAIC aircraft data, J. Geophys. Res.-Atmos., 115, D24304, https://doi.org/10.1029/2010JD014284, 2010. a
Sonntag, D.: Important new values of the physical constants of 1986, vapour pressure formulations based on the ITS-90, and psychrometer formulae, Z. Meteorol., 40, 340–344, https://doi.org/10.1127/metz/3/1994/51, 1990. a
Taszarek, M., Allen, J. T., Marchio, M., and Brooks, H. E.: Global climatology and trends in convective environments from ERA5 and rawinsonde data, npj Climate and Atmospheric Science, 4, 35, https://doi.org/10.1038/s41612-021-00190-x, 2021. a
Tinney, E. N., Homeyer, C. R., Elizalde, L., Hurst, D. F., Thompson, A. M., Stauffer, R. M., Vömel, H., and Selkirk, H. B.: A Modern Approach to a Stability-Based Definition of the Tropopause, Mon. Weather Rev., 150, 3151–3174, https://doi.org/10.1175/MWR-D-22-0174.1, 2022. a, b, c
Wernli, H. and Schwierz, C.: Surface Cyclones in the ERA-40 Dataset (1958–2001). Part I: Novel Identification Method and Global Climatology, J. Atmos. Sci., 63, 2486–2507, https://doi.org/10.1175/JAS3766.1, 2006. a
Wirth, V. and Szabo, T.: Sharpness of the extratropical tropopause in baroclinic life cycle experiments, Geophys. Res. Lett., 34, L02809, https://doi.org/10.1029/2006GL028369, 2007. a, b
Xu, H., Guo, J., Tong, B., Zhang, J., Chen, T., Guo, X., Zhang, J., and Chen, W.: Characterizing the near-global cloud vertical structures over land using high-resolution radiosonde measurements, Atmos. Chem. Phys., 23, 15011–15038, https://doi.org/10.5194/acp-23-15011-2023, 2023. a
Short summary
In this work, the influence of humidity on the properties of the tropopause is studied. The tropopause is the interface between the troposphere and the stratosphere and represents a barrier for the transport of air masses between the troposphere and the stratosphere. We consider not only the tropopause itself, but also a layer around it called the tropopause inversion layer (TIL). It is shown that the moister the underlying atmosphere is, the more this layer acts as a barrier.
In this work, the influence of humidity on the properties of the tropopause is studied. The...
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