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In this study, the ability of dynamical downscaling for reduction of artificial climate trends in global reanalysis is tested in China. Dynamical downscaling is performed using a 60-km horizontal r...

A validation study of land surface temperature (LST) obtained from the Ka band (37 GHz) vertically polarized brightness temperature over northern China is presented. The remotely sensed LST derived jointly by the Vrije Universiteit Amsterdam and the NASA Goddard Space Flight Center (VUA-NASA) from the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) were compared to the daily in-situ top soil temperature/infrared surface temperature observations from eleven/three Enhanced Coordinated Observation stations in arid and semi-arid regions of northern China. The VUA-NASA LST from the descending path exhibited a stronger correspondence to the in-situ infrared surface temperature than soil temperature observations, whereas correlations (R2) of the latter ranged from 0.41 to 0.86. Meanwhile, the ascending overpass LST was generally warmer than the in-situ soil temperature observations at all stations, and the correlation (R2) was between 0.07 and 0.72. Furthermore, the correlation of ...

Assessing large-scale patterns of gross pri- mary production (GPP) in arid and semi-arid (ASA) areas is important for both scientific and practical purposes. Remote sensing-based models, which integrate satellite data with input from ground-based meteorological meas- urements and vegetation characteristics, improve spatially extended estimates of vegetation productivity with high accuracy. In this study, the authors simulated GPP in ASA areas by integrating moderate resolution imaging spectral radiometer (MODIS) data with eddy covariance and me- teorological measurements at the flux tower sites using the Vegetation Photosynthesis Model (VPM), which is a re- mote sensing-based model for analyzing the spatial pat- tern of GPP in different land cover types. The field data were collected by coordinating observations at nine sta- tions in 2008. The results indicate that in the region dur- ing the growing season GPP was highest in cropland sites, second highest in woodland sites, and lowest in grassland sites. VPM captured the temporal and spatial characteris- tics of GPP for different land covers in ASA areas. Further, Enhanced Vegetation Index (EVI) had a strong liner rela- tionship with GPP in densely vegetated areas, while the Normalized Difference Vegetation Index (NDVI) had a strong liner relationship with GPP over less dense vegeta- tion. This study demonstrates the potential of satel- lite-driven models for scaling-up GPP, which is a key component for studying the carbon cycle at regional and