Spline Interpolation of Spatial-temporal Climate Data for China
YAN Hong(Chinese Academy of Forestry, Beijing 100091,China)
Surfaces of monthly mean temperature and rainfall were fitted with data from meteorological station network recorded in period of 1951-2000 using spline interpolation technique and a spatiotemporal climate database was developed by coupling the fitted spline surfaces to underlying digital elevation model in scale of 1/10 degree to expand the use of long term climate data for climate modeling. Two data formats are available for this database. Gridded files can be used by GIS for data retrieval, climate mapping and secondary climate variables deriving. Graphic files are suitable to visual display of climate change through time with a browsing program developed by Java. The statistical analysis indicated the residual errors of the fitted surfaces were correspondently reduced while the density of original data point increased from 200 up to 700 stations. Thin plate smoothing spline is advantageous to data which is limited either in time period or spatial density.