A High Spatial Resolution Monthly Air Temperature And Precipitation Gridded Dataset Over China And Its Preliminary Applications

The gridded climatic dataset plays an important role in studying the global and regional climate changes and variability.The international gridded datasets of different areas,span of time,spatial and temporal resolution have been established since 1970s.The gridded datasets of Climatic Research Unit(CRU),Global Historical Climatology Network(GHCN),Goddard Institute for Space Studies(GISS),Berkeley and Smith were widely quoted by Intergovernmental Panel on Climate Change(IPCC)and many scientists.The similar studies have started in China since 1990s,however,a lot of the gridded datasets over China were relatively at the poor resolution(more than 0.5°×0.5°,or 56 kilometers×56 kilometers).The available climatic datasets in China are either with low spatial resolution or cover a short period of time-term.This study constructed the high spatial resolution monthly air temperature and precipitation gridded datasets(LZU0025 in short)based on the gauge observations obtained from China Meteorological Administration using the software ANUSPLIN.This dataset covers the period from 1951 to 2012 with a horizontal resolution of 0.025° latitude by 0.025°latitude over China.In order to evaluate the quality of the dataset,the air temperature and precipitation of LZU0025 have been compared with the observation of meteorological stations.Our evaluations showed that there was a little difference between our grids' value and observation from selected meteorological stations(e.g.,Hailaer).Our gridded data are also significantly correlated to the observations.We also compared our datasets with some commonly used climate datasets from the Climatic Research Unit(CRU),Climate Prediction Center(CPC)and University of Delaware(UDEL).The results suggested that our air temperature and precipitation datasets exhibit coherent spatial and temporal variations compared to the UDEL and CPC.Our datasets,however,can better describe the spatial and temporal characteristics of temperature and precipitation under the complex topography.The characteristics of temperature and precipitation over China were further analyzed using our LZU0025 dataset.The annual and seasonal temperature increased significantly during.1951-2012.The winter temperature increased most,followed by the spring and autumn temperature.The summer temperature is also increasing but with much slower rate.In the recent 62 years,the annual temperature has a significant warming trend since 1980s.The statistics of the annual and seasonal precipitation over China during 1951-2012 shows that summer precipitation--51.7%,spring precipitation--22.6%,autumn precipitation--19.4%and winter precipitation--6.3%.In the recent 62 years,average precipitation in China has been decreasing,led to a drier condition since 1960.Additionally,our results based on LZU0025 show that the temperature over China has been changing from low level in the early years(1951-1980)to high level in recent decades(after 1980),suggesting that the China has been changing from cold to warm during the past 60 years.There was no significant in annual precipitation over entire China controlled by westerly,and decreased in northern China that controlled by Asian monsoon.