Cheng, X.; Yi, L. & Bendix, J. (2021): <b>Cloud top height retrieval over Arctic Ocean using cloud-shadow method based on MODIS</b>. <i>Atmospheric Research</i> <b>253</b>, 105468.
Resource Description
Title:
Cloud top height retrieval over Arctic Ocean using cloud-shadow method based on MODIS
FOR816dw ID:
408
Publication Date:
2021-01-01
License and Usage Rights:
Resource Owner(s):
Individual:
Xueying Cheng
Contact:
email:
webmaster <at> lcrs.de
Individual:
Li Yi
Contact:
email:
webmaster <at> lcrs.de
Individual:
Jörg Bendix
Contact:
email:
bendix <at> staff.uni-marburg.de
Deutschhausstraße 12
Room No. 02 A 48
35032 Marburg
Faculty of Geography
Germany
Abstract:
Cloud top height (CTH) plays an important role in the Earth’s radiation budget and thus in climate change. <br/>
However, accurate CTH retrieval based on satellite data remains a challenge when using currently widespread <br/>
methods based on passive remote sensing satellite data, particularly over the Arctic Ocean. It is well known that <br/>
using geometric correlation between CTH and cloud-shadow distance along the normal direction of sunlight, <br/>
cloud-edge top height (CETH) can be determined. However, this cloud-shadow method (CSM) exhibited larger <br/>
CTH errors due to low-resolution weather satellite data of the past. The aim of the paper is to analyze the effect of <br/>
higher-resolution images (MODIS with 250-m resolution) on CSM accuracy. We present a method in which CETH <br/>
is first retrieved using the MODIS data, and to calculate CTH in the center of cloud region by combining the <br/>
calculated CETH and cloud top brightness temperature using an environmental temperature lapse rate method. <br/>
We validated 14 cases over the Arctic Ocean by the CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder <br/>
Satellite Observations) CTH lidar product and another two cases by radiosonde data. CSM revealed better per-<br/>
formance (mean difference is 0.45 km and standard deviation is 0.92 km) compared to the operational MODIS <br/>
CTH product (mean difference is 0.78 km and standard deviation is 1.78 km), when validated by the CALIPSO <br/>
product. When validated by sounding data, CSM also performed better than the MODIS CTH product: the CSM <br/>
CTH errors are 0.41 and 0.52 km in two sounding cases, while the corresponding MODIS CTH errors are 1.10 <br/>
and 1.07 km. The CSM technique especially showed better performance for double-deck cloud systems. We <br/>
conclude that further improvements in CTH accuracy based on CSM can be achieved by mainly using higher- <br/>
resolution satellite imagery.
Keywords:
| MODIS | Fog | Arctic | top height | Calipso |
Literature type specific fields:
ARTICLE
Journal:
Atmospheric Research
Volume:
253
Page Range:
105468
Publisher:
Elsevier
Metadata Provider:
Individual:
Jörg Bendix
Contact:
email:
bendix <at> staff.uni-marburg.de
Deutschhausstraße 12
Room No. 02 A 48
35032 Marburg
Faculty of Geography
Germany
