Characteristics of atmospheric aerosols observed by lidar at five TCCON sites extending from 43°N to 45°S

We have been observing the vertical distributions of atmospheric aerosols with two wavelength polarization lidar systems at five Total Carbon Column Observing Network (TCCON) sites of Rikubetsu (43.46°N, 143.77°E), Tsukuba (36.05°N, 140.12°E), Saga (33.24°N, 130.29°E) in Japan, Burgos (18.53°N, 120.65°E) in the Philippines and Lauder (45.04°S, 169.68°E) in New Zealand. The main purpose of these lidar observations is to investigate the influence of atmospheric aerosols and thin cirrus clouds on the Greenhouse gases Observing SATellite (GOSAT) data with simultaneous TCCON Fourier Transform Spectrometer (FTS) observations during the GOSAT overpass time. Also, these lidar data provide indispensable information on characteristics of space and time variations of tropospheric and stratospheric aerosols in the northern low and middle latitudes and the southern middle latitude. Aerosols originating from fires in Siberia were observed at Rikubetsu on 18-20 May and were also observed at Tsukuba on 19 May in 2016. The aerosols covered the northern part of Japan, and the extinction-to-backscatter ratio of the aerosols was about 60 sr and the aerosol optical depth (AOD) at 532 nm was larger than 1.0. The column amount of CO measured by Rikubetsu TCCON FTS increased simultaneously. Aerosols from the polluted area in the North China Plain and dust particles from the Gobi Desert were observed in spring time at Saga, and large AOD could impact on GOSAT data. On the other hand, tropospheric AOD is usually very low at Lauder. Lidar observation at Burgos just started in March 2017, and using the Raman scattering technique, water vapor profiles were obtained up to 5 km in nighttime. These lidar systems detected some increases in stratospheric aerosols by the volcanic eruptions of Sarychev Peak, Puyehue-Cordon Caulle, Nabro and Calbuco from the launch of GOSAT in 2009 to 2016. Increased stratospheric aerosols after the Calbuco eruption might significantly impact GOSAT data observed over Lauder.