Seasonal and Diurnal Variations of Aerosol Extinction Profile 1 and Type Distribution from CALIPSO 5-year Observations

43 The new level 3 aerosol profile data derived from the Cloud-Aerosol Lidar and 44 Infrared Pathfinder Satellite Observations (CALIPSO) provide multi-year global 45 aerosol distribution with high vertical resolution. We analyzed seasonal and diurnal 46 variations of the vertical distributions of aerosol properties represented by this 47 CALIPSO data for the period of five years. Results show that dust, smoke and 48 polluted dust are the most frequently detected aerosol types during all seasons. Dust is 49 the dominant type, especially in the middle-upper troposphere, over most areas during 50 boreal spring and summer; while smoke and polluted dust tend to dominate during 51 biomass burning seasons. The seasonal variations of dust layer top height and dust 52 contribution to all-aerosol extinction are positively correlated with the seasonal 53 variation of dust occurrence frequency. Southeast Asia has the least seasonal variation 54 of aerosol properties. The seasonal cycle of aerosol properties over West Australia is 55 similar to that over biomass burning regime areas, despite of its desert regime. In 56 general, smoke is detected more frequently from lower to middle troposphere; clean 57 marine and polluted continental (polluted dust) aerosols are detected more (less) 58 frequently in the lower troposphere, during nighttime than daytime. The all-aerosol 59 extinction is generally larger and aerosol layer top is detected at high altitudes more 60 frequently during nighttime than daytime. The diurnal changes of aerosol properties 61 are similar within the same aerosol emission regime. Dust extinction shows little 62 diurnal variation except when dust is the dominant aerosol type. 63 64 65-3