Satellite Based Downward Long Wave Radiation by Various Models in Northeast Asia

• Main Authors: Chanyang Sur, Hyunwoo Kim, Minha Choi
• Format: Article
• Language: English
• Published: Chinese Geoscience Union 2014-01-01
• Series: Terrestrial, Atmospheric and Oceanic Sciences
• Subjects: Downward long wave radiation; Moderate resolution imaging spectroradiometer; Air temperature; Vapor pressure; Brutsaert; Abramowitz
• Online Access: http://tao.cgu.org.tw/images/attachments/v256p893.pdf

Satellite-based downward long wave radiation measurement under clear sky conditions in Northeast Asia was conducted using five well-known physical models (Brunt 1932, Idso and Jackson 1969, Brutsaert 1975, Satterlund 1979, Prata 1996) with a newly proposed global Rld model (Abramowitz et al. 2012). Data from two flux towers in South Korea were used to validate downward long wave radiation. Moderate resolution imaging spectroradiometer (MODIS) atmospheric profile products were used to develop the Rld models. The overall root mean square error (RMSE) of MODIS Rld with respect to two ecosystem-type flux towers was determined to be ≈ 20 W m-2. Based on the statistical analyses, MODIS Rld estimates with Brutsaert (1975) and Abramowitz et al. (2012) models were the most applicable for evaluating Rld for clear sky conditions in Northeast Asia. The Abramowitz Rld maps with MODIS Ta and ea showed reasonable seasonal patterns, which were well-aligned with other biophysical variables reported by previous studies. The MODIS Rld map developed in this study will be very useful for identifying spatial patterns that are not detectable from ground-based Rld measurement sites.