Seasonal and diurnal variations of aerosol extinction profile and type distribution from CALIPSO 5‐year observations

Abstract

[1] The new Level 3 aerosol profile data derived from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) provide a multiyear global aerosol distribution with high vertical resolution. We analyzed seasonal and diurnal variations of the vertical distributions of aerosol properties represented by 5-year CALIPSO data. Results show that dust, smoke, and polluted dust are the most frequently detected aerosol types during all seasons. Dust is the dominant type, especially in the middle to upper troposphere, over most areas during boreal spring and summer, while smoke and polluted dust tend to dominate during biomass burning seasons. The seasonal variations of dust layer top height and dust contribution to all-aerosol extinction are positively correlated with the seasonal variation of the dust occurrence frequency. The seasonal cycle of aerosol properties over west Australia is similar to that over biomass burning regime areas, despite its desert regime. In general, smoke is detected more frequently from the lower to middle troposphere; clean marine and polluted continental aerosols are detected more frequently, while polluted dust is detected less frequently, in the lower troposphere during nighttime than daytime. The all-aerosol extinction is generally larger, and the aerosol layer top is detected at high altitudes more frequently during nighttime than daytime. The diurnal changes of aerosol properties are similar within the same aerosol regime. Dust extinction shows little diurnal variation except when dust is the dominant aerosol type. The results contribute to an initial global 3-D aerosol climatology which will likely be extended and improved in the future.

A GCM investigation of dust aerosol impact on the regional climate of North Africa and South/East Asia

“…North Africa is heavily influenced by dust with significant year-round dust emissions as shown in the observations derived from the Total Ozone Mapping Spectrometer (TOMS) aerosol index (AI), with maximum emissions from May to August (Engelstaedter et al 2006). During boreal spring and summer, the air over North Africa is almost permanently loaded with significant amounts of dust (Huang et al 2013). A large amount of dust particles are carried by the general circulations from North Africa to Europe, Middle East, and across the Atlantic to the southeastern United States, leading to the formation of a major dust belt.…”

Trans-Pacific transport and evolution of aerosols: evaluation of quasi-global WRF-Chem simulation with multiple observations

“…Previous studies have found that simulated aerosol vertical distributions differ significantly, which can affect the assessments of aerosol impacts on climate and air quality (e.g., Schulz et al, 2006;Textor et al, 2006). CALIPSO with its unique capability provides an opportunity to assess model simulation of aerosol vertical distributions (e.g., Huang et al, 2013). Figure 11 shows the vertical distributions of annual mean aerosol extinction coefficients for 2010-2014 averaged over the three sub-regions from the CALIPSO retrieval and the corresponding WRFChem simulation under cloud-free conditions.…”

CALIPSO lidar level 3 aerosol profile product: version 3 algorithm design

“…Researchers have used the CALIOP level 3 product to investigate seasonal variability of the vertical distribution and extinction profiles (Huang et al, 2013;Xu et al, 2015). It has provided insights into global aerosol source attribution (Prijith et al, 2013) and how the vertical distribution of aerosols relates to atmospheric circulation (Alizadeh-Choobari et al, 2014;Prijith et al, 2016) and to ice cloud nucleation potential (Tan et al, 2014).…”