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1.
In order to understand the processes of land surface-atmosphere interaction over desertification area, it is indispensable to utilize of satellite remote sensing. Two scenes of Landsat TM were used to produce a set of maps of surface reflectance, MSAVI, vegetation coverage, surface temperature, net radiation, soil heat flux, sensible heat flux and latent heat flux. Statistical analysis based on these maps revealed some quantitative significant land surface characteristics. Future developments of the method are also discussed.  相似文献   

2.
In order to understand the processes of land surface-atmosphere interaction over de-sertification area, it is indispensable to utilize of satellite remote sensing. Two scenes of LandsatTM were used to produce a set of maps of surface reflectance, MSAVI, vegetation coverage, sur-face temperature, net radiation, soil heat flux, sensible heat flux and latent heat flux. Statisticalanalysis based on these maps revealed some quantitative significant land surface characteristics.Future developments of the method are also discussed.  相似文献   

3.
Mass and energy transfer between soil, vegetation and atmosphere is the process that allows to maintain an adequate energy and water balance in the earth–atmosphere system. However, the evaluation of the energy balance components, such as the net radiation and the sensible and latent heat fluxes, is characterized by significant uncertainties related to both the dynamic nature of heat transfer processes and surfaces heterogeneity. Therefore, a detailed land use classification and an accurate evaluation of vegetation spatial distribution are required for an accurate estimation of these variables. For this purpose, in the present article, a pixel‐oriented supervised classification was applied to obtain land use maps of the Basilicata region in Southern Italy by processing three Landsat TM and ETM+ satellite images. An accuracy analysis based on the overall accuracy index and the agreement Khat of Cohen coefficient showed a good performance of the applied classification methodology and a good quality of the obtained maps. Subsequently, these maps were used in the application of a simplified two‐source energy balance model for estimating the actual evapotranspiration at a regional scale. The comparison between the simulations made by applying the simplified two‐source energy balance model and the measurements of evapotranspiration at a lysimetric station located in the study area showed the applicability and the validity of the proposed methodology. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

4.
As surface exchange processes are highly non-linear and heterogeneous in space and time, it is important to know the appropriate scale for the reasonable prediction of these exchange processes. For example, the explicit representation of surface variability has been vital in predicting mesoscale weather events such as late-afternoon thunderstorms initiated by latent heat exchanges in mid-latitude regions of the continental United States. This study was undertaken to examine the effects of different spatial scales of input data on modeled fluxes, so as to better understand the resolution needed for accurate modeling. A statistical procedure was followed to select two cells from the Southern Great Plains 1997 hydrology experiment region, each 20 km×20 km, representing the most homogeneous and the most heterogeneous surface conditions (based on soil and vegetation) within the study region. The NOAH-OSU (Oregon State University) Land Surface Model (LSM) was employed to estimate surface energy fluxes. Three scales of study (200 m, 2 and 20 km) were considered in order to investigate the impacts of the aggregation of input data, especially soil and vegetation inputs, on the model output. Model results of net radiation and latent, sensible and ground heat fluxes were compared for the three scales. For the heterogeneous area, the model output at the 20-km resolution showed some differences when compared with the 200-m and 2-km resolutions. This was more pronounced in latent heat (12% decrease), sensible heat (22% increase), and ground heat flux (44% increase) estimation than in net radiation. The scaling effects were much less for the relatively homogeneous land area with 5% increase in sensible heat and 4% decrease in ground heat flux estimation. All of the model outputs for the 2- and 20-km resolutions were in close agreement. The results suggested that, for this study region, soils and vegetation input resolution of about 2 km should be chosen for realistic modeling of surface exchange processes. This resolution was sufficient to capture the effects of sub-grid scale heterogeneity, while avoiding the data and computational difficulties associated with higher spatial resolutions.  相似文献   

5.
Water and energy fluxes are inextricably interlinked within the interface of the land surface and the atmosphere. In the regional earth system models, the lower boundary parameterization of land surface neglects lateral hydrological processes, which may inadequately depict the surface water and energy fluxes variations, thus affecting the simulated atmospheric system through land-atmosphere feedbacks. Therefore, the main objective of this study is to evaluate the hydrologically enhanced regional climate modelling in order to represent the diurnal cycle of surface energy fluxes in high spatial and temporal resolution. In this study, the Weather Research and Forecasting model (WRF) and coupled WRF Hydrological modelling system (WRF-Hydro) are applied in a high alpine catchment in Northeastern Tibetan Plateau, the headwater area of the Heihe River. By evaluating and intercomparing model results by both models, the role of lateral flow processes on the surface energy fluxes dynamics is investigated. The model evaluations suggest that both WRF and coupled WRF-Hydro reasonably represent the diurnal variations of the near-surface meteorological fields, surface energy fluxes and hourly partitioning of available energy. By incorporating additional lateral flow processes, the coupled WRF-Hydro simulates higher surface soil moisture over the mountainous area, resulting in increased latent heat flux and decreased sensible heat flux of around 20–50 W/m2 in their diurnal peak values during summertime, although the net radiation and ground heat fluxes remain almost unchanged. The simulation results show that the diurnal cycle of surface energy fluxes follows the local terrain and vegetation features. This highlights the importance of consideration of lateral flow processes over areas with heterogeneous terrain and land surfaces.  相似文献   

6.
Estimation of evapotranspiration (ET) is of great significance in modeling the water and energy interactions between land and atmosphere. Negative correlation of surface temperature (Ts) versus vegetation index (VI) from remote sensing data provides diagnosis on the spatial pattern of surface soil moisture and ET. This study further examined the applicability of Ts–VI triangle method with a newly developed edges determination technique in estimating regional evaporative fraction (EF) and ET at MODIS pixel scale through comparison with large aperture scintillometer (LAS) and high‐level eddy covariance measurements collected at Changwu agro‐ecological experiment station from late June to late October, 2009. An algorithm with merely land and atmosphere products from MODIS onboard Terra satellite was used to estimate the surface net radiation (Rn) and soil heat flux. In most cases, the estimated instantaneous Rn was in good agreement with surface measurement with slight overestimation by 12 W/m2. Validation results from LAS measurement showed that the root mean square error is 0.097 for instantaneous EF, 48 W/m2 for instantaneous sensible heat flux, and 30 W/m2 for daily latent heat flux. This paper successfully presents a miniature of the overall capability of Ts–VI triangle in estimating regional EF and ET from limited number of data. For a thorough interpretation, further comprehensive investigation needs to be done with more integration of remote sensing data and in‐situ surface measurements. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

7.
应用定西地区的陆面过程野外观测资料和四次EOS_MODIS卫星资料,对典型的西北半干旱雨养农业区的基本地表特征参数进行反演,在此基础上对各能量通量和蒸散量进行估算,进而分别分析其季节和空间变化.结果表明：应用卫星数据估算的各参量的相对误差基本都在20%以内,其空间和时间变化基本反映了当地的实际情况;区域各通量和日蒸散量分布极不均匀,表现为四季相差比较大的单峰型变化特征,冬季最小、其次是秋季、夏春两季最大;与面积较大的中、低植被覆盖度区域相比,小范围的高植被覆盖度区域的地表净辐射、潜热和日蒸散量相对较高,土壤热通量和显热通量相对较低,并且都在春、夏季节表现得更加显著.低、中植被覆盖度区的各能量通量的季节变化不显著的特征反映了半干旱西北雨养农业区土壤的干土层相对比较厚的特征.  相似文献   

8.
沙漠陆面过程参数化与模拟   总被引：4，自引：2，他引：2       下载免费PDF全文
郑辉  刘树华 《地球物理学报》2013,56(7):2207-2217
沙漠地区植被稀疏、干旱少雨,其陆面物理过程具有与全球其它地区显著不同的特点.本文利用巴丹吉林沙漠观测资料,分析和计算了地表反照率、比辐射率、粗糙度和土壤热容量、热传导系数等关键陆面过程参数,建立了适合于沙漠地区的陆面过程模式DLSM (Desert Land Surface Model),并与NOAH陆面过程模式的模拟结果和观测资料进行了比较.结果表明:巴丹吉林沙漠地表反照率为0.273,比辐射率为0.950,地表粗糙度为1.55×10-3 m,土壤热容量和热扩散系数分别为1.08×106 J·m-3·K-1和3.34×10-7 m2·s.辐射传输、感热输送和土壤热传导过程是影响沙漠地区地表能量平衡的主要物理过程.通过对这三种过程的准确模拟检验,DLSM能够较准确地模拟巴丹吉林沙漠地气能量交换特征;短波辐射、长波辐射和感热通量的模拟结果与观测值间的标准差分别为7.98,6.14,33.9 W·m-2,与NOAH陆面过程模式的7.98,7.72,46.6 W·m-2的结果接近.地表反照率是沙漠地区最重要的陆面过程参数,地表反照率增大5%,向上短波辐射通量随之增加5%,感热通量则减小2.8%.本文研究结果对丰富陆面过程参数化方案,改进全球陆面过程模式、气候模式具有参考意义.  相似文献   

9.
Human activities result in deforestation, expansion of cropland, grassland degradation, urbanization and other large-scale land use/cover change; among these, cropland expansion is one of the most important processes. To understand the effects of cropland expansion on seasonal temperatures over China, two 21-year simulations (spanning January 1, 1980–December 31, 2000), using the Regional Integrated Environmental Model System (RIEMS 2.0), were performed. The two simulations comprised current realistic land use/cover patterns and the previous vegetation cover without crop expansion, to investigate the impact of crop expansion on seasonal temperatures over China. The results showed that due to cropland expansion: (1) the most obvious changes occurred in the maximum temperatures, followed by the mean surface air temperatures, and the minimum temperatures were the least affected; (2) the summer mean maximum temperatures decreased in most parts of eastern China, and the temperatures changed significantly in most parts of northeast China, north China and central China (p < 0.05); (3) the surface air temperatures, maximum temperatures and minimum temperatures in summer decreased in the different regions by between −0.03 and −0.76 °C (the greatest temperature changes occurred in southwest China, and the smallest were in northeast China); (4) the net radiation flux and latent heat flux increased, while the sensible flux decreased, when semi-desert vegetation was replaced by dry land crops, in both summer and winter seasons, and the converse occurred when irrigated crops were replaced by dry land crops. In addition, the net radiation flux and sensible heat flux decreased, and the latent heat flux increased when short grass and tall grass were replaced dry land crops, as well as when dry land crops were replaced by irrigated crops.  相似文献   

10.
Land surface energy fluxes are required in many environmental studies, including hydrology, agronomy and meteorology. Surface energy balance models simulate microscale energy exchange processes between the ground surface and the atmospheric layer near ground level. Spatial variability of energy fluxes limits point measurements to be used for larger areas. Remote sensing provides the basis for spatial mapping of energy fluxes. Remote‐sensing‐based surface energy flux‐mapping was conducted using seven Landsat images from 1997 to 2002 at four contiguous crop fields located in Polk County, northwestern Minnesota. Spatially distributed surface energy fluxes were estimated and mapped at 30 m pixel level from Landsat Thematic Mapper and Enhanced Thematic Mapper images and weather information. Net radiation was determined using the surface energy balance algorithm for land (SEBAL) procedure. Applying the two‐source energy balance (TSEB) model, the surface temperature and the latent and sensible heat fluxes were partitioned into vegetation and soil components and estimated at the pixel level. Yield data for wheat and soybean from 1997 to 2002 were mapped and compared with latent heat (evapotranspiration) for four of the fields at pixel level. The spatial distribution and the relation of latent heat flux and Bowen ratio (ratio of sensible heat to latent heat) to crop yield were studied. The root‐mean‐square error and the mean absolute percentage of error between the observed and predicted energy fluxes were between 7 and 22 W m−2 and 12 and 24% respectively. Results show that latent heat flux and Bowen ratio were correlated (positive and negative) to the yield data. Wheat and soybean yields were predicted using latent heat flux with mean R2 = 0·67 and 0·70 respectively, average residual means of −4·2 bushels/acre and 0·11 bushels/acre respectively, and average residual standard deviations of 16·2 bushels/acre and 16·6 bushels/acre respectively (1 bushel/acre ≈ 0·087 m3 ha−1). The flux estimation procedure from the SEBAL‐TSEB model was useful and applicable to agricultural fields. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

11.
The default fractional vegetation cover and terrain height were replaced by the estimated fractional vegetation cover, which was calculated by the Normalized Difference Vegetation Index(NDVI) of Earth Observing System Moderate-Resolution Imaging Spectroradiometer(EOS-MODIS) and the Digital Elevation Model of the Shuttle Radar Topography Mission(SRTM) system. The near-surface meteorological elements over northeastern China were assimilated into the three-dimensional variational data assimilation system(3DVar) module in the Weather Research and Forecasting(WRF) model. The structure and daily variations of air temperature, humidity, wind and energy fields over northeastern China were simulated using the WRF model. Four groups of numerical experiments were performed, and the simulation results were analyzed of latent heat flux, sensible heat flux, and their relationships with changes in the surface energy flux due to soil moisture and precipitation over different surfaces. The simulations were compared with observations of the stations Tongyu, Naiman, Jinzhou, and Miyun from June to August, 2009. The results showed that the WRF model achieves high-quality simulations of the diurnal characteristics of the surface layer temperature, wind direction, net radiation, sensible heat flux, and latent heat flux over semiarid northeastern China in the summer. The simulated near-surface temperature, relative humidity, and wind speed were improved in the data assimilation case(Case 2) compared with control case(Case 1). The simulated sensible heat fluxes and surface heat fluxes were improved by the land surface parameterization case(Case 3) and the combined case(Case 4). The simulated temporal variations in soil moisture over the northeastern arid areas agree well with observations in Case 4, but the simulated precipitation should be improved in the WRF model. This study could improve the land surface parameters by utilizing remote sensing data and could further improve atmospheric elements with a data assimilation system. This work provides an effective attempt at combining multi-source data with different spatial and temporal scales into numerical simulations. The assimilation datasets generated by this work can be applied to research on climate change and environmental monitoring of arid lands, as well as research on the formation and stability of climate over semiarid areas.  相似文献   

12.
China's Loess Plateau is located at the edge of the Asian summer monsoon in a transition zone of climate and ecology. In the Loess Plateau, climate and environments change along with space, which has an obvious impact on the spatial distribution of surface energy fluxes. Because of scarce land-surface observation sites and short observation time in this area, previous studies have failed to fully understand the land-surface energy balance characteristics over the entire the Loess Plateau and their effect mechanisms. In this paper, we first test the simulation ability of the Community Land Model(CLM) model by comparing its simulated data with observed data. Based on the simulation data for the Loess Plateau over the past thirty years, we then analyze the spatial distribution of surface energy fluxes and compare the pattern differences between the area averages for the driest year and wettest year. Furthermore, we analyze the relationship between the spatial distribution of the components of the surface energy balance with longitude, latitude, altitude, precipitation and temperature. The main results are as follows: the spatial distribution of surface energy fluxes are significantly different, with the surface net radiation and sensible heat flux increasing from south to north and latent heat flux and soil heat flux decreasing from southeast to northwest. The sensible heat flux at the driest point is nearly twice as high as that at the wettest point, whereas the latent heat flux and soil heat flux at the driest point are half as much as that at the wettest point. The impact of variations of annual precipitation on the components of the surface energy balance is also obvious, and the maximum magnitude of the changes to the sensible heat flux and latent heat flux is nearly 30%. To a certain extent, geographical factors(including longitude, latitude, and altitude) and climate factors(including temperature and precipitation) affect the surface energy fluxes. However, the surface net radiation is more closely related to latitude and altitude, sensible heat flux is more closely related to the monsoon rainfall and latitude, and latent heat flux and soil heat flux are more closely related to the monsoon rainfall.  相似文献   

13.
This paper discusses the preliminary results of a study on the vegetation pattern and its relationship with meteorological parameters in and around Istanbul. The study covers an area of over 6800 km2 consisting of urban and suburban centers, and uses the visible and near-infrared bands of Landsat. The spatial variation of the Normalized Difference Vegetation Index (NDVI) and meteorological parameters such as sensible heat flux, momentum flux, relative humidity, moist static energy, rainfall rate and temperature have been investigated based on observations in ten stations in the European (Thracian) and Anatolian parts of Istanbul. NDVI values have been evaluated from the Landsat data for a single day, viz. 24 October 1986, using ERDAS in ten different classes. The simultaneous spatial variations of sensible heat and momentum fluxes have been computed from the wind and temperature profiles using the Monin-Obukhov similarity theory. The static energy variations are based on the surface meteorological observations. There is very good correlation between NDVI and rainfall rate. Good correlation also exists between: NDVI and relative humidity; NDVI, sensible heat flux and relative humidity; NDVI, momentum flux and emissivity; and NDVI, sensible heat flux and emissivity. The study suggests that the momentum flux has only marginal impact on NDVI. Due to rapid urbanization, the coastal belt is characterized by reduced NDVI compared to the interior areas, suggesting that thermodynamic discontinuities considerably influence the vegetation pattern. This study is useful for the investigation of small-scale circulation models, especially in urban and suburban areas where differential heating leads to the formation of heat islands. In the long run, such studies on a global scale are vital to gain accurate, timely information on the distribution of vegetation on the earth’s surface. This may lead to an understanding of how changes in land cover affect phenomena as diverse as the atmospheric CO2 concentrations, the hydrological cycle and the energy balance at the surface-atmosphere interface.  相似文献   

14.
—The influence of soil moisture and vegetation variation on simulation of monsoon circulation and rainfall is investigated. For this purpose a simple land surface parameterization scheme is incorporated in a three-dimensional regional high resolution nested grid atmospheric model. Based on the land surface parameterization scheme, latent heat and sensible heat fluxes are explicitly estimated over the entire domain of the model. Two sensitivity studies are conducted; one with bare dry soil conditions (no latent heat flux from land surface) and the other with realistic representation of the land surface parameters such as soil moisture, vegetation cover and landuse patterns in the numerical simulation. The sensitivity of main monsoon features such as Somali jet, monsoon trough and tropical easterly jet to land surface processes are discussed.¶Results suggest the necessity of including a detailed land surface parameterization in the realistic short-range weather numerical predictions. An enhanced short-range prediction of hydrological cycle including precipitation was produced by the model, with land surface processes parameterized. This parameterization appears to simulate all the main circulation features associated with the summer monsoon in a realistic manner.  相似文献   

15.
巢湖对冬季陆面辐射和热量过程的影响   总被引：3，自引：1，他引：2  
从物理气候学的观点出发,分析了湖泊对水体和陆地辐射平衡和热量平衡各分量的影响。以巢湖地区冬季观测资料为例,揭示了在晴稳天气湖陆风环流对陆面显热输送的影响,以及在冷平流天气,湖泊对上下风方陆面显热输送的影响。  相似文献   

16.
Jing Wang  Qiang Yu  Xuhui Lee 《水文研究》2007,21(18):2474-2492
Understanding the exchange processes of energy and carbon dioxide (CO2) in the soil–vegetation–atmosphere system is important for assessing the role of the terrestrial ecosystem in the global water and carbon cycle and in climate change. We present a soil–vegetation–atmosphere integrated model (ChinaAgrosys) for simulating energy, water and CO2 fluxes, crop growth and development, with ample supply of nutrients and in the absence of pests, diseases and weed damage. Furthermore, we test the hypotheses of whether there is any significant difference between simulations over different time steps. CO2, water and heat fluxes were estimated by the improving parameterization method of the coupled photosynthesis–stomatal conductance–transpiration model. Soil water evaporation and plant transpiration were calculated using a multilayer water and heat‐transfer model. Field experiments were conducted in the Yucheng Integrated Agricultural Experimental Station on the North China Plain. Daily weather and crop growth variables were observed during 1998–2001, and hourly weather variables and water and heat fluxes were measured using the eddy covariance method during 2002–2003. The results showed that the model could effectively simulate diurnal and seasonal changes of net radiation, sensible and latent heat flux, soil heat flux and CO2 fluxes. The processes of evapotranspiration, soil temperature and leaf area index agree well with the measured values. Midday depression of canopy photosynthesis could be simulated by assessing the diurnal change in canopy water potential. Moreover, the comparisons of simulated daily evapotranspiration and net ecosystem exchange (NEE) under different time steps indicated that time steps used by a model affect the simulated results. There is no significant difference between simulated evapotranspiration using the model under different time steps. However, simulated NEE produces large differences in the response to different time steps. Therefore, the accurate calculation of average absorbed photosynthetic active radiation is important for the scaling of the model from hourly steps to daily steps in simulating energy and CO2 flux exchanges between winter wheat and the atmosphere. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

17.
J. A. Leach  R. D. Moore 《水文研究》2010,24(17):2369-2381
Stream temperature and riparian microclimate were characterized for a 1·5 km wildfire‐disturbed reach of Fishtrap Creek, located north of Kamloops, British Columbia. A deterministic net radiation model was developed using hemispherical canopy images coupled with on‐site microclimate measurements. Modelled net radiation agreed reasonably with measured net radiation. Air temperature and humidity measured at two locations above the stream, separated by 900 m, were generally similar, whereas wind speed was poorly correlated between the two sites. Modelled net radiation varied considerably along the reach, and measurements at a single location did not provide a reliable estimate of the modelled reach average. During summer, net radiation dominated the surface heat exchanges, particularly because the sensible and latent heat fluxes were normally of opposite sign and thus tended to cancel each other. All surface heat fluxes shifted to negative values in autumn and were of similar magnitude through winter. In March, net radiation became positive, but heat gains were cancelled by sensible and latent heat fluxes, which remained negative. A modelling exercise using three canopy cover scenarios (current, simulated pre‐wildfire and simulated complete vegetation removal) showed that net radiation under the standing dead trees was double that modelled for the pre‐fire canopy cover. However, post‐disturbance standing dead trees reduce daytime net radiation reaching the stream surface by one‐third compared with complete vegetation removal. The results of this study have highlighted the need to account for reach‐scale spatial variability of energy exchange processes, especially net radiation, when modelling stream energy budgets. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

18.
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19.
This paper presents measurements of the energy balance (radiation, sensible heat flux, evaporation) from a sub‐arctic hillside in northern Finland for a summer season. Comparisons are also made with a nearby wetland site. The hillslope measurements show an equal partition of the radiant energy into sensible and latent heat flux. The evaporative ratio of just over one half was remarkably constant throughout the season, despite very large day‐to‐day and diurnal variations of temperature, humidity deficit and radiation input. This conservative behaviour of the evaporation was caused by a strong rise in effective surface resistance to evaporation with increasing vapour pressure deficit. This suggests a strong physiological control on the evaporation, with stomata closing at times of high evaporative demand. There was no obvious impact of soil‐water stress on the evaporation. However, a comparison with the evaporation measured at a nearby mire site in 1997 suggests that the mire has a significantly lower surface resistance, even when the impact of a significantly lower humidity deficit in the earlier year is taken into account. The measurements are used to test, off‐line, the performance of MOSES (Meteorological Office Surface Exchange Scheme), a simple, but comprehensive, land surface model. The sensitivity of the energy exchanges to the thermal properties of the top soil layer (a surrogate for the upper soil/vegetation layer) is investigated with the use of the model. It is found that the evaporation is insensitive to these properties; they do, however, influence the partition of energy between the sensible heat flux and the ground heat flux (and hence the soil temperatures). It is suggested that the model needs to represent the thermal properties of the canopy more realistically. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

20.
Surface soil heat flux(G0) is an indispensable component of the surface energy balance and plays an important role in the estimation of surface evapotranspiration(ET). This study calculated G0 in the Heihe River Basin based on the thermal diffusion equation, using the observed soil temperature and moisture profiles, with the aim to analyze the spatial-temporal variations of G0 over the heterogeneous area(with alpine grassland, farmland, and forest). The soil ice content was estimated by the difference in liquid soil water content before and after the melting of the frozen soil and its impact on the calculation of G0 was further analyzed. The results show that:(1) the diurnal variation of G0 is obvious under different underlying surfaces in the Heihe River Basin, and the time when the daily maximum value of G0 occurs is a few minutes to several hours earlier than that of the net radiation flux, which is related to the soil texture, soil moisture, soil thermal properties, and the vegetation coverage;(2) the net radiation flux varies with season and reaches the maximum in summer and the minimum in winter, whereas G0 reaches the maximum in spring rather than in summer, because more vegetation in summer hinders energy transfer into the soil;(3) the proportions of G0 to the net radiation flux are different with seasons and surface types, and the mean values in January are 25.6% at the Arou site, 22.9% at the Yingke site and 4.3% at the Guantan site, whereas the values in July are 2.3%, 1.6% and 0.3%, respectively; and(4) G0 increases when the soil ice content is included in thermal diffusion equation, which improves the surface energy balance closure by 4.3%.  相似文献   

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