Estimation of High Spatial-Resolution Clear-Sky Land Surface-Upwelling Longwave Radiation from VIIRS/S-NPP Data

Abstract

Surface-upwelling longwave radiation (LWUP) is an important component of the surface radiation budget. Under the general framework of the hybrid method, the linear models and the multivariate adaptive regression spline (MARS) models are developed to estimate the 750 m instantaneous clear-sky LWUP from the top-of-atmosphere (TOA) radiance of the Visible Infrared Imaging Radiometer Suite (VIIRS) channels M14, M15, and M16. Comprehensive radiative transfer simulations are conducted to generate a huge amount of representative samples, from which the linear model and the MARS model are derived. The two models developed are validated by the field measurements collected from seven sites in the Surface Radiation Budget Network (SURFRAD). The bias and root-mean-square error (RMSE) of the linear models are −4.59 W/m 2 and 16.15 W/m 2 , whereas those of the MARS models are −5.23 W/m 2 and 16.38 W/m 2 , respectively. The linear models are preferable for the production of the operational LWUP product due to its higher computational efficiency and acceptable accuracy. The LWUP estimated by the linear models developed from VIIRS is compared to that retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS). They agree well with each other with bias and RMSE of −0.15 W/m 2 and 25.24 W/m 2 respectively. This is the first time that the hybrid method has been applied to globally estimate clear-sky LWUP from VIIRS data. The good performance of the developed hybrid method and consistency between VIIRS LWUP and MODIS LWUP indicate that the hybrid method is promising for producing the long-term high spatial resolution environmental data record (EDR) of LWUP.

Assessment of the Long-Term High-Spatial-Resolution Global LAnd Surface Satellite (GLASS) Surface Longwave Radiation Product Using Ground Measurements

“…T HE surface longwave (LW) radiation (4-100 μm) is one of the two components of the surface radiation budget (SRB), and it consists of the surface longwave upward radiation (LWUP), the surface longwave downward radiation (LWDN), and the surface longwave net radiation (LWNR) [1], [2]. The surface LW radiation is a significant diagnostic parameter for land surface, atmospheric, and ocean models, and it is the most important variable for investigating biogeochemical processes, greenhouse effects, and global climate changes [3]- [9].…”

Estimation and Evaluation of 15 Minute, 40 Meter Surface Upward Longwave Radiation Downscaled from the Geostationary FY-4B AGRI

“…SULR is the sum of the thermal radiation emitted by a surface and the reflected SDLR. To retrieve the SULR from remote sensing data, state-of-the-art methods can be categorized into two main approaches: the temperature-broadband emissivity physical method [4,9,26] and the hybrid method [2,27,28]. The temperature-broadband emissivity physical method estimates SULR by utilizing the LST, broadband emissivity, and SDLR.…”

A New Linear Relation for Estimating Surface Broadband Emissivity in Arid Regions Based on FTIR and MODIS Products

“…Jin et al converted MODIS TIR narrowband emissivities into BBE, deriving the estimated BBE improved the performance of global climate models over desert areas [6]. As the number of satellites with TIR channels increases, this method has been extended to Landsat, Fengyun Visible Infrared Imaging Radiometer Suite (VIIRS) and Spinning Enhanced Visible Infra-Red Imager (SEVIRI) satellite Data [19][20][21][22]. Based on MODIS narrowband emissivity products, the second method has been used to produce a global land surface satellite (GLASS) BBE dataset for the years from 1981 to 2010 [23][24][25].…”