Optimal use of space-borne advanced infrared and microwave soundings for regional numerical weather prediction

NCUIR > Research Center > Center for Space and Remote Sensing Research > journal & Dissertation > Item 987654321/101712

Please use this identifier to cite or link to this item: https://ir.lib.ncu.edu.tw/handle/987654321/101712

Title:	Optimal use of space-borne advanced infrared and microwave soundings for regional numerical weather prediction
Authors:	劉千義;Liu, Chian-Yi;Kuo, Szu-Chen;Lim, Agnes;Hsu, Shen-Cha;Tseng, Kuo-Hsin;Yeh, Nan-Ching;Yang, Yu-Chi
Contributors:	太空及遙測研究中心
Keywords:	advanced infrared sounding;Assimilation;data assimilation;Infrared;Infrared spectroscopy;Mathematical models;microwave sounding;numerical weather prediction;Sounding;Spectra;Troposphere;Weather forecasting
Date:	2016-10-01
Issue Date:	2026-04-21 14:41:30 (UTC+8)
Publisher:	MDPI Multidisciplinary Digital Publishing Institute;MDPI AG
Abstract:	摘要： Satellite observations can either be assimilated as radiances or as retrieved physical parameters to reduce error in the initial conditions used by the Numerical Weather Prediction (NWP) model. Assimilation of radiances requires a radiative transfer model to convert atmospheric state in model space to that in radiance space, thus requiring a lot of computational resources especially for hyperspectral instruments with thousands of channels. On the other hand, assimilating the retrieved physical parameters is computationally more efficient as they are already in thermodynamic states, which can be compared with NWP model outputs through the objective analysis scheme. A microwave (MW) sounder and an infrared (IR) sounder have their respective observational limitation due to the characteristics of adopted spectra. The MW sounder observes at much larger field-of-view (FOV) compared to an IR sounder. On the other hand, MW has the capability to reveal the atmospheric sounding when the clouds are presented, but IR observations are highly sensitive to clouds, The advanced IR sounder is able to reduce uncertainties in the retrieved atmospheric temperature and moisture profiles due to its higher spectral-resolution than the MW sounder which has much broader spectra bands. This study tries to quantify the optimal use of soundings retrieved from the microwave sounder AMSU and infrared sounder AIRS onboard the AQUA satellite in the regional Weather and Research Forecasting (WRF) model through three-dimensional variational (3D-var) data assimilation scheme. Four experiments are conducted by assimilating soundings from: (1) clear AIRS single field-of-view (SFOV); (2) retrieved from using clear AMSU and AIRS observations at AMSU field-of-view (SUP); (3) all SFOV soundings within AMSU FOVs must be clear; and (4) SUP soundings which must have all clear SFOV soundings within the AMSU FOV. A baseline experiment assimilating only conventional data is generated for comparison. Various atmospheric state variables at different pressure levels are used to assess the impact from assimilating these different data by comparing them with European Centre for Medium Range Weather Forecast (ECMWF) reanalysis data. Results indicate assimilation of SUP soundings improve the mid and upper troposphere, whereas assimilation of SFOV soundings has positive impact on the lower troposphere. Two additional assimilation experiments are carried out to determine the combination of SUP and SFOV soundings that will provide the best performance throughout the troposphere. The results indicate that optimal combination is to assimilate clear-sky matched IR retrievals with non-matched MW soundings. 出版者： MDPI AG 出版日期： 2016-10-01 出處： Remote sensing (Basel, Switzerland), 2016-10, Vol.8 (10), p.816-816 資源來源： Directory of Open Access Journals 識別號： ISSN: 2072-4292 識別號： EISSN: 2072-4292 識別號： DOI: 10.3390/rs8100816
Appears in Collections:	[Center for Space and Remote Sensing Research ] journal & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	38	View/Open

社群 sharing

Loading...