Plateau surface energy balance components and interannual variability in response to climate fluctuations

Abstract

In this paper land surface observations and meteorological data are received from Semiarid Climate and Environment Observatory of Lanzhou University (SACOL) and Yuzhong Station from 2006 to 2012. The climate changes of temperature and precipitation in the seven years are analyzed in Yuzhong, and the inter-annual variation of the components of surface energy balance in land surface is discussed. The Bowen ratio and the energy inter-annual fluctuation imbalance are also studied. Explorations of surface energy balance components as well as the land surface process parameters feedback on the temperature, precipitation interannual fluctuations on the Loess Plateau are carried out. Results show that the surface energy components are responsible to the fluctuations of the climate background. But the sensitivity varies; the net radiation and air temperature are more relevant to each other, and the sensible heat and latent heat have a better correlation with precipitation. Discussions are divided into summer and winter half year results, in which the winter half year balance component surface has a better correlation with climatic fluctuations. In the winter half year, each component has a high degree of correlation with temperature, showing that in this area each component of the land surface energy balance component corresponding to the change of temperature is more remarkable The rising trend of Bowen ratio is corresponding to the reduction of precipitation, indicating that the drought is deepened The change of the energy closure shows that the deepening of energy balance unclosure is due to the change of the climate background.