| In this paper, land surface observations and meteorological data are used from Semi-arid Climate and Environment Observatory of Lanzhou University (SACOL) and Yuzhong Station from 2006 to 2012.7 years of climate change of temperature and precipitation are analyzed in Yuzhong and the inter-annual variation of the components of surface energy balance of land surface is discussed. The Bowen ratio, energy inter-annual fluctuations imbalance are also studied. There are exploring the surface energy balance components as well as the land surface process parameters feedback on the temperature, precipitation interannual fluctuations on the Loess Plateau. The results show that the surface energy components are respond to the fluctuations of the climate background. But the sensitivity varies, net radiation and air temperature is more relevant, sensible heat and latent heat have a better correlation of precipitation. Discussion is divided into summer and winter half year results that the winter half year balance component surface have a better correlation with climatic fluctuations. In winter half year, each component has a high degree of correlation with temperature, showing in this area each component of the land surface energy balance component winter half year corresponding to the change of temperature is more remarkable. The rising trend of Bowen ratio is corresponding with the reduction of the precipitation, which described 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.In this paper,2006-2012 land surface observation data of Lanzhou University, semi-arid climate and environmental observation stations (SACOL station)and meteorological data of Yuzhong Station are be used to analysis the land surface radiation budget component of the response to climate fluctuations. And also study the interannual variability of surface albedo and discusses the feedback of various parameters on the Loess Plateau land surface process to the temperature and precipitation interannual fluctuations. According to the type of precipitation, the year is divided into winter and summer in order to get more significant variability and correlation. The results show that, trends of temperature and precipitation in recent years match the overall total Loess Plateau warming and drying trend. And the shallow surface soil moisture and temperature showed a good response to air temperature and precipitation. In concluding, land surface condition and the combined effects of climatic factors are the reason of the change of the land surface albedo. Through the distinguish inquiry of winter and summer, correlation coefficient of long-wave radiation components and climatic factors are more relevant than correlation coefficient of short-wave radiation components and climatic factors.To explore seasonal changes of land surface processes, diurnal variation of radiation processes and land surface energy balance components sub-humid lands on behalf of the station Qingyang stations of four seasons are discussed. Changes of radiation budget and energy balance components between the diurnal variation in different weather conditions of different seasons in this area are discussed. The land surface process daily change in this area is studied in different surface conditions and different temperatures and humidity background. In conclusion, land surface water and heat exchange process have a great relationship with the atmosphere, soil temperature and humidity condition and the underlying surface vegetation situation in this region. As representatives of sub-humid land Qingyang station, distribution of net radiation has subtle differences with a number of other stations in the Loess Plateau and there are also representative of the characteristics in four seasons of its own.To better understand the the space-time differences in land surface water and heat fluxes between different climatic zones, the surface data is used from "Experimental Study of the Loess Plateau land surface processes (LOPEX) ". And anlysised Dingxi station, Pingliang station, Qingyang station and SACOL station’s radiation budget and energy balance component features. In this paper, also used a variation of the above station winter and summer under sunny conditions to discuss the land surface radiation and energy characteristics of spatial difference and influence mechanism in the Loess Plateau. The results showed that the difference between the stations is subject to certain seasonal variation in the surface energy balance. And surface heat flux has a different impact factor in summer and winter. Variation of net radiation is showing the opposite state in summer and winter. Seasonal changes in the radiation budget by less pronounced impact and the difference between each station depends on which climate zone. |
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