We systematically examined that how various large-scale atmospheric conditions (ACs) affects the distributions of aerosol optical depth (AOD) over eastern China. We extract and depict nine main types for AOD (six polluted types and three clean types) in autumn over eastern China. The results provide convincing evidence that the general characteristics of atmospheric circulations contribute significantly to the different types of regional pollution.

Global warming will induce large-scale insect outbreaks in boreal forests. Our results from field and laboratory experiments, satellite observations and global-scale modelling suggest that more frequent insect outbreaks, in addition to temperature-dependent increases in VOC emissions, could result in substantial increases in biogenic SOA formation and therefore affect both aerosol direct and indirect forcing of climate at regional scales. This should be considered in future climate predictions.

Three different continuous datasets for complex refractive indices of hematite are employed in climate models, the real role of iron-oxides in the optical properties of dust aerosols becomes a key scientific question, and we address this problem by considering different refractive indices, size distributions, and more logical weight fractions and mixing states of hematite. More laboratory measurements should be taken into account when assessing the effect of mineral dust on climate forcing.

The expedited near-real-time Level 1.5 Cloud-Aerosol Lidar with Orthogonal Polarization version 3 products were evaluated against data from the ground-based European Aerosol Research Lidar Network. The statistical framework and results of the 3-year evaluation of 48 CALIOP overpasses with ground tracks within a 100km distance from operating EARLINET stations are presented.

This study attempts to determine the consequences of the changes in tropospheric aerosol burden arising from substantial reductions in emissions of SO2 and NOx associated with control measures under the Clean Air Act especially on trends in solar radiation. Comparisons of model results with observations of aerosol optical depth, aerosol concentration, and radiation demonstrate that the coupled WRF-CMAQ model is capable of replicating the trends well even though it tends to underestimate the AOD.

The research paper presents the first comprehensive overview of field measurements with the CCN Counter performed at a large number of locations around the world within the EUCAARI framework. The paper sheds light on the CCN number concentrations and activated fractions around the world and their dependence on the water vapour supersaturation ratio, the dependence of aerosol hygroscopicity on particle size, and seasonal and diurnal variation of CCN activation and hygroscopic properties.

We analyze the direct radiative impact of an intense African dust plume on orographic precipitation in the western Mediterranean in the fall of 2012 using high-resolution simulations from a convection permitting mesoscale model validated against measurements acquired during the first special observation period of HyMeX. We show that the dust's direct radiative effect in such a dynamical environment is not sufficient to impact 24h of accumulated rainfall over the Cevennes in the dust simulation.

The addition of NO2 to atmospheric particle formation simulations based on ozone reactions with tree-emitted monoterpenes results in changing particle composition and mass yields, with effects that vary across the range of studied monoterpenes. For alpha-pinene, a dominantly emitted terpene in the United States, NO2 addition suppresses particle formation, while for others, particle yields remain high.

The mathematical description of finite volume coalescing systems relies on the multivariate master equation. However, due to its complexity, it has analytical solutions only for a limited number of kernels and initial conditions. In this paper, in an effort to solve this problem, we have introduced a novel numerical approach to calculate the solution of the multivariate coalescence master equation that works for any type of kernel and initial conditions.

We discuss the shape of ice water content (IWC) vertical profiles in high ice clouds and its effect on radiative properties of these clouds, both in short- and in long-wave bands (SW and LW). We suggest a set of primitive shapes (rectangular, isosceles trapezoid, lower and upper triangle) and propose a statistical parameterization using ice water path (IWP) as a single parameter. We estimate and explain simulated differences in LW/SW atmospheric radiances for suggested IWC shapes.

The annual average concentrations (1.3-47.0µg N m-3) and dry plus wet/bulk deposition fluxes (2.9-83.3kg N ha-1 yr-1) of inorganic Nr species ranked by land use as urban > rural > background sites and by regions as north China > southeast China > southwest China > northeast China > northwest China > Tibetan Plateau, reflecting the impact of anthropogenic Nr emission. Average dry and wet/bulk N deposition fluxes were 20.6 ± 11.2 and 19.3 ± 9.2kg kg N ha-1 yr-1 across China, respectively.

This paper assesses the resolution dependance of clouds and precipitation over Germany by numerical simulations with the COnsortium for Small-scale MOdeling model for 7 cases of 2013. By means of a series of grid-refinement resolution tests, the variability of clouds and precipitation and how this variability changes with model resolution are investigated. The performance of the model at these resolutions is of general relevance to the research community as well as to operational forecasters

Aerosols affect cloud properties, and the radiative effects of clouds. Human emissions of aerosol particles and precursors may alter the radiative effects of clouds. This is generally a cooling effect that offsets other warming effects of human emissions of gases. Simulating these aerosol effects on clouds are highly dependent on the formulation of the microphysical (cloud droplet scale) processes. This work uses model simulations to show these effects are large, and depend on certain processes.

We discuss the spatiotemporal variations in aerosol characteristics, measured along the Northern Sea Route in RV Akademik Fedorov and RV Professor Khljustin cruises. The variability ranges of the average aerosol parameters in separate seas and regions were from 2.5 to 24cm-3 for number concentration of particles; from 830 to 2970ngm-3 for aerosol mass concentrations; from 20 to 150ngm-3 for black carbon mass concentrations; and from 0.03 to 0.19 for aerosol optical depth (0.5um).

We report 2 years of measurements of submicron particles at the SORPES station and provide a comprehensive understanding of main factors controlling temporal variation of the aerosol size distribution and NPF in eastern China. The number concentrations of total particles at Nanjing were comparable to other Chinese megacities but the frequency of NPF was much higher. Year-to-year differences of meteorological conditions could significantly influence the seasonal cycle of NPF and growth.

The CMAM30 data set takes a chemistry-climate model and relaxes the dynamics to reanalysis, which can then provide chemistry fields not available from the reanalysis data set. This paper addresses this gap by comparing temperature, water vapour, ozone and methane to satellite data to determine and document any biases in the model fields. The lack of ozone destruction and dehydration in the SH polar vortex is shown to be due to the treatment of polar stratosphere clouds in the model.

Variability in aerosol optical properties relevant to radiative forcing were studied on several timescales at four continental North American NOAA-ESRL sites. Light scattering and intensive properties varied most on seasonal scales while absorption variability on weekly and diurnal timescales was comparable to its seasonal variability. Large reductions in light scattering were observed at the two long-term sites (relative to late 1990s), along with a smaller contribution by sub-1µm particles.

We present the new version of the BIRA-IASB algorithm for the retrieval of H2CO columns from OMI and GOME-2A and B measurements. Validation results at seven stations in Europe, China and Africa confirm the capacity of the satellite measurements to resolve diurnal variations in H2CO columns. Furthermore, vertical profiles derived from MAX-DOAS measurements in Beijing and in Bujumbura are used for a more detailed validation exercise. Finally trends are estimated using 10 years of OMI observations.

We present an empirical method to retrieve actual evapotranspiration (ET) at a spatial resolution of 250m for the eastern Mediterranean based on observed relationships between satellite vegetation indices and eddy covariance ET. Our model was successfully evaluated against two physically based models and calculated ET from water catchment balances along rainfall gradient. In the absence of high-resolution models, our model is expected to contribute to the ecohydrological study of this region.

We firstly evaluated the Spectral Radiation-Transport Model for Aerosol Species combined with a non-hydrostatic regional model through comparing the simulation results and satellite observations, both in horizontal and vertical. The dust and anthropogenic aerosols in summer over the Tibetan Plateau are evaluated, and their distributions over the TP are presented. The transport of these aerosols over the Tibetan Plateau is also explored via combining the simulation results and reanalysis data.

We developed Arizona dust records in 2005-2013 using multiple surface and remote sensing observation data sets. The inter-annual variability of dust events was anticorrelated with three drought indicators (PDSI, satellite NDVI and soil moisture), and stronger dust activity was found in the afternoon than in the morning due to stronger winds and drier soil. Impact of a recent dust event accompanied by a stratospheric ozone intrusion was evaluated with various observational and modeling data sets.

In east Asia, emissions of O3 precursors have gradually increased and O3 concentrations are expected to increase in the near future. Ieodo Ocean Research Station (IORS), located in the East China Sea, is a unique research tower suitable for observing continental outflows from east Asia. In this study, we present long-term measurements of O3 at IORS, describe their characteristic variations, and evaluate their continental influence on the regional background concentrations of O3.

A high-resolution emission inventory of air pollutants and CO2 for Nanjing, a typical city in eastern China, is developed, incorporating the best available local information from on-site surveys. The temporal and spatial distribution of the emissions and the correlation between specific species of the inventory are assessed by comparisons with observations and other inventories at larger spatial scale. The emission inventory provides a basis to consider the quality of instrumental observations.

The manuscript is the first paper to validate and discuss the high-resolution vertical profiles of aerosols using a ceilometer in Beijing, China. We introduce the contribution of aerosols during different air pollution episodes in Beijing. Also, we seize the opportunity of emission reduction during APEC to study the contribution of aerosols. The results are helpful to provide guidance in redefining coordinated emission control strategies to control the regional pollution over northern China.