气候变化领域集成服务门户(CCPortal): Evaluation of aerosol number concentrations from CALIPSO with ATom airborne in situ measurements

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DOI	10.5194/acp-22-7143-2022
	Evaluation of aerosol number concentrations from CALIPSO with ATom airborne in situ measurements
	Choudhury, Goutam; Ansmann, Albert; Tesche, Matthias
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	7143
结束页码	7161
卷号	22 期号:11 页码:19
英文摘要	The present study aims to evaluate the available aerosol number concentration (ANC) retrieval algorithms for spaceborne lidar CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) aboard the CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) satellite with the airborne in situ measurements from the ATom (Atmospheric Tomography Mission) campaign. We used HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory model) to match both the measurements in space and identified 53 cases that were suitable for comparison. Since the ATom data include the dry aerosol extinction coefficient, we used kappa parameterization to adjust the ambient measurements from CALIOP to dry conditions. As both the datasets have a different vertical resolution, we regrid them to uniform height bins of 240 m from the surface to a height of 5 km. On comparing the dry extinction coefficients, we found a reasonable agreement between the CALIOP and ATom measurements with Spearman's correlation coefficient of 0.715. Disagreement was found mostly for retrievals above 3 km altitude. Thus, to compare the ANC, which may vary by orders of magnitude in space and time, we further limit the datasets and only select those height bins for which the CALIOP-derived dry extinction coefficient is within +/- 50 % of the ATom measurements. This additional filter further increases the probability of comparing the same air parcel. The altitude bins which qualify the extinction coefficient constraint are used to estimate ANC with a dry radius > 50 nm (n(50)(,dry)) and > 250nm (n(250)(,dry)). The POLIPHON (Polarization Lidar Photometer Networking) and OMCAM (Optical Modelling of CALIPSO Aerosol Microphysics) algorithms were used to estimate the n(50)(,dry) and n(250)(,dry). The POLIPHON estimates of n(50)(,dry) and n(250)(,dry) were found to be in good agreement with the in situ measurements, with a correlation coefficient of 0.829 and 0.47, root mean square error (RMSE) of 234 and 13 cm(-3), and bias of -97 and 4 cm(-3), respectively. The OMCAM estimates of n(50)(,dry) and n(250)(,dry) were also in reasonable agreement with the in situ measurements, with a correlation coefficient of 0.823 and 0.463, RMSE of 247 and 13 cm(-3), and bias of 44 and 4 cm(-3), respectively. However, we found that the OMCAM-estimated n(50)(,dry) were about an order of magnitude less than the in situ measurements for marine-dominated cases. We propose a modification to the OMCAM algorithm by using an AERONET-based marine model. With the updated OMCAM algorithm, the n(50)(,dry) agrees well with the ATom measurements. Such concurrence between the satellite-derived ANC and the independent ATom in situ measurements emboldens the use of CALIOP in studying the aerosol-cloud interactions.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000805200700001
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/273780
作者单位	Leipzig University; Leibniz Institut fur Tropospharenforschung (TROPOS)
推荐引用方式 GB/T 7714	Choudhury, Goutam,Ansmann, Albert,Tesche, Matthias. Evaluation of aerosol number concentrations from CALIPSO with ATom airborne in situ measurements[J],2022,22(11):19.
APA	Choudhury, Goutam,Ansmann, Albert,&Tesche, Matthias.(2022).Evaluation of aerosol number concentrations from CALIPSO with ATom airborne in situ measurements.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(11),19.
MLA	Choudhury, Goutam,et al."Evaluation of aerosol number concentrations from CALIPSO with ATom airborne in situ measurements".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.11(2022):19.