气候变化领域集成服务门户(CCPortal): Improving the Understanding of CrIS Full Spectral Resolution Nonlocal Thermodynamic Equilibrium Radiances Using Spectral Correlation

CCPortal

DOI	10.1029/2020JD032710
	Improving the Understanding of CrIS Full Spectral Resolution Nonlocal Thermodynamic Equilibrium Radiances Using Spectral Correlation
	Li Z.; Menzel W.P.; Jung J.; Lim A.; Li J.; Matricardi M.; López-Puertas M.; DeSouza-Machado S.; Strow L.L.
发表日期	2020
ISSN	2169897X
卷号	125 期号:16
英文摘要	In recent years, significant progress has been made in fast radiative transfer model (RTM) simulation of daytime nonlocal thermodynamic equilibrium (NLTE) emission. However, NLTE remains as one important reason that prevents the hyperspectral shortwave infrared (SWIR) radiance observations from being assimilated into numerical weather prediction (NWP) models. To better understand the limitations of existing RTM-based NLTE simulation, this study introduces a new statistical method, called Spectral Correlations to Estimate Non-Local Thermal Equilibrium (SCENTE), to estimate the NLTE radiances in the Cross-track Infrared Sounder (CrIS) SWIR radiance observations. SCENTE is applied to four typical season days, including spring equinox, summer solstice, fall equinox, and winter solstice. By analyzing calculation/background minus observation (BMO) of CrIS SWIR brightness temperature (BT), results show that SCENTE characterizes the NLTE well with standard deviation of differences (STD) comparable to observation noise for both daytime and nighttime, while the community RTM (CRTM) has substantially larger STD at night, mainly due to the lack of daytime NLTE just beyond the day/night terminator and the lack of aurora-related NLTE. Detailed investigation of the biases of BMO shows that CRTM underestimates daytime SWIR NLTE effects by 0.76 K, while SCENTE overestimates SWIR NLTE effects by 0.70 K. The overestimation is because SCENTE uses CRTM-simulated SWIR local thermodynamic equilibrium (LTE) radiances in the training, which is underestimated by 0.70 K in BT. SCENTE, complementary to RTM-based simulations, can be used for quality control of SWIR radiances for assimilation and retrieval of atmospheric soundings. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	CO2 bands; data assimilation; NLTE; shortwave infrared radiances; sounding retrieval
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185839
作者单位	Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin-Madison, Madison, WI, United States; ECMWF, Reading, United Kingdom; Instituto de Astrofisica de Andalucia, CSIC, Granada, Spain; Joint Center for Earth Systems Technology, University of Maryland, Baltimore County, Baltimore, MD, United States; Department of Physics, University of Maryland, Baltimore County, Baltimore, MD, United States
推荐引用方式 GB/T 7714	Li Z.,Menzel W.P.,Jung J.,et al. Improving the Understanding of CrIS Full Spectral Resolution Nonlocal Thermodynamic Equilibrium Radiances Using Spectral Correlation[J],2020,125(16).
APA	Li Z..,Menzel W.P..,Jung J..,Lim A..,Li J..,...&Strow L.L..(2020).Improving the Understanding of CrIS Full Spectral Resolution Nonlocal Thermodynamic Equilibrium Radiances Using Spectral Correlation.Journal of Geophysical Research: Atmospheres,125(16).
MLA	Li Z.,et al."Improving the Understanding of CrIS Full Spectral Resolution Nonlocal Thermodynamic Equilibrium Radiances Using Spectral Correlation".Journal of Geophysical Research: Atmospheres 125.16(2020).