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China is a large country by area. In situ monitoring of the environment cannot meet the demand of the society. For large areas, remote sensing is the only viable technology for environmental monitoring of the entire area. Although satellite observation capabilities as well as remotely sensed data acquired on board of satellites from both within and outside China are widely available, research is rare that targets the entire territory of China for environmental monitoring. In this paper, the process of environmental change has been categorized into changes in driving forces, environmental change, materials transport and transformation, concentration and abundance change, exposure and infection change of human and ecosystems, and impacts. The potential in monitoring changes in these various aspects is assessed. The progress of environmental change monitoring over the entire territory of China is reviewed. It is suggested that at the methodological level, remote sensing should not only be applied to observation and experiments as well as understanding the change mechanism, but also be coupled with environmental simulation and forecasting so as to support environmental policy making. At the application level, remote sensing should be used beyond its traditional application fields to include species diversity, biological invasion, public health, air and water quality monitoring. Finally, at the technical level, systematic research should be devoted to the improvement of operational and automatic use of remotely sensed data. [ABSTRACT FROM AUTHOR]

In this paper, with the application of satellite thermal infrared remote sensing technique, nine land surface temperature distribution maps of Changbaishan Tianchi volcano area are retrieved from nine thermal infrared images which are taken from 1999 to 2008. In terms of NDVI (Normalized Difference Vegetation Index), we classify the surface cover of the study area into three types, i.e. vegetation (forest), mixture of soil and vegetation (short grasses), and bare rock. The average temperature of each type of surface covers is calculated first, and then the average daily temperature record from Tianchi meteorological station is subtracted in order to reduce the effect of weather variation. Finally, thermal anomalies of three types of surface cover in Changbaishan Tianchi volcano area in the period of 1999 to 2008 are obtained, which is believed to reflect the magmatic activity in the magma chamber under Tianchi volcano caldera. Our results indicate that temperature of the study area increased with an intermittent tendency during 1999 to 2005, but dropped after 2005, and then maintained a relatively stable state from 2006 to 2008. Such a tendency of annual temperature variation possibly caused by magmatic activity is correlated with the results observed by means of seismic monitoring, ground deformation from GPS measurement, and volcanic gas geochemistry monitoring in the same area. It is implied that the upward intrusion of magma may cause temperature increase, and such temperature variation is great enough so that could be detected by using satellite thermal infrared remote sensing technology. [ABSTRACT FROM AUTHOR]

The HJ-1A satellite was successfully launched on September 6, 2008. The inclusion of a HyperSpectral Imager (HSI) as one of the payloads of the HJ-1A Satellite is a major milestone in the field of the remote sensing in China. It is also the first Fourier transform imaging spectrometer routinely used to acquire scientific data from a satellite orbiting Earth. This paper briefly introduces the basic imaging theories of the spatially modulated Fourier transform imaging spectrometer, and then discusses the theoretical analysis and algorithms of spectrum reconstruction. Results of the operational spectrum reconstruction for the raw data of the HJ-1A satellite Fourier transform HSI are presented. At present, the algorithms and processing flow have been used successfully in the Ground Data Processing System (GDPS) built by the China Center for Resource Satellite Data and Applications (CRESDA). [ABSTRACT FROM AUTHOR]

The scientific design and preliminary results of the data assimilation component of the Global-Regional Prediction and Assimilation System (GRAPES) recently developed in China Meteorological Administration (CMA) are presented in this paper. This is a three-dimensional variational (3DVar) assimilation system set up on global and regional grid meshes favorable for direct assimilation of the space-based remote sensing data and matching the frame work of the prediction model GRAPES. The state variables are assumed to decompose balanced and unbalanced components. By introducing a simple transformation from the state variables to the control variables with a recursive or spectral filter, the convergence rate of iteration for minimization of the cost function in 3DVar is greatly accelerated. The definition of dynamical balance depends on the characteristic scale of the circulation considered. The ratio of the balanced to the unbalanced parts is controlled by the prescribed statistics of background errors. Idealized trials produce the same results as the analytic solution. The results of real data case studies show the capability of the system to improve analysis compared to the traditional schemes. Finally, further development of the system is discussed. [ABSTRACT FROM AUTHOR]

Recent climatic changes have affected terrestrial net primary productivity (NPP). This paper presents an investigation of the impact of climatic changes on Chinese terrestrial vegetation NPP by analyzing 18 years' (1982 to 1999) climatic data and satellite observations of vegetation activity. Results indicate that climatic changes in China have eased some critical climatic constraint on plant growth. (1) From 1982 to 1999, modeled NPP increased by 1.42% · a-1 in water-limited regions of Northwest China, 1.46% · a-1 in temperature-limited regions of Northeast China and Tibet Plateau, and 0.99% · a-1 in radiation-limited regions of South China and East China. (2) NPP increased by 24.2%, i.e. 0.76 petagram of carbon (Pg C) over 18 years in China. Changes in climate (with constant vegetation) directly contributed nearly 11.5% (0.36 Pg C). Changes in vegetation (with constant climate) contributed 12.4% (0.40 Pg C), possibly as a result of climate-vegetation feedbacks, changes in land use, and growth stimulation from other mechanisms. (3) Globally, NPP declined during all three major El Niño events (1982 to 1983, 1987 to 1988, and 1997 to 1998) between 1982 and 2000, but Chinese vegetation productivity responded differently to them because of the monsoon dynamics. In the first three events (1982 to 1983, 1987 to 1988, and 1992), Chinese vegetation NPP declined, while in the later two events (1993, 1997 to 1998) increasing obviously. [ABSTRACT FROM AUTHOR]