Black carbon (BC), which consists of the strongest light-absorbing particles (LAPs) in snow, has been regarded as a potential factor accelerating regional climate change and the melting of snow cover globally. In this study, we used remote sensing (Moderate-resolution Imaging Spectroradiometer, MODIS) observations combined with a snow albedo model (Snow, Ice, and Aerosol Radiation, SNICAR) and a radiative transfer model (Santa Barbara DISORT Atmospheric Radiative Transfer, SBDART) to retrieve the radiative forcing (RF) by BC in snow (R-MODIS(BC)) across Xinjiang, China, for the first time. The observations in January-February show that the concentrations of BC (equivalent BC) in snow ranged from 44.08 to 1949.9 ng g(-1), with an average of 536.71 ng g(-1). The lowest concentrations of BC were on the border of the Altay region (AR), with a median concentration in snow of 98.5 ng g(-1). South of this area in the industrial region (Tianshan Mountain North Slope Economic Development Belt, TMNSEDB), the median concentration of BC in snow was 913.2 ng g(-1) R-MODIS(BC) presents distinct spatial variability, with the minimum (3.01W m(-2)) in the AR and the maximum (40.2W m(-2)) near industrial areas in TMNSEDB. The regional mean R-MODIS(BC) was 20.43 +/- 7.3 W m(-2) in Xinjiang, and the average values of the impurity index (I-LAPs) and SGS in the region were 0.273 and 241.38 mu m, respectively. Moreover, based on the multiple linear regressions, the BC emission intensity values were significantly correlated with I-LAPs and RF, and the correlation reached 0.681 and 0.661, respectively; thus, the BC emission could explain above 75% of the spatial variance of BC contents in TMNSEDB, confirming the reasonability of the spatial patterns of retrieved RFMODISBC in Xinjiang. Additionally, we found that the distribution of R-MODIS(BC) in northern Xinjiang is dominated by I-LAPs and BC emissions. We validated R-MODIS(BC) using in situ RF estimates (R-site(estimate)), and the error was 24.05 W m(-2); furthermore, the biases in R-MODIS(BC) were negatively correlated with the BC concentrations and ranged from 24.3% to 326% in Xinjiang.

来源平台：ATMOSPHERIC ENVIRONMENT