The Penman-Monteith equation is useful for computing evaporation rates of uniform surfaces, such as dense vegetation or bare soil. This equation becomes less useful for evaluation of evaporation rates at the regional scale, where surfaces are generally characterized by a patchy combination of vegetation and soil. This is particularly true in the arid and semi-arid regions of the world. The appr...

The impact of ‘non-rainfall’ water on soil is important in arid zones. In that environment, the amount of dew can exceed that of rainfall, or even be the sole source of liquid water for plants. However, since plants cover only a small fraction of the desert surface, such assessments apply only to a small proportion of the area. In the absence of fog, dew formation and direct water vapor adsorpt...

physical characteristics of different features in desert is a reflection of severe thermal and climatic conditions. in this paper, diurnal surface temperature patterns of important surface features in lut desert were studied and the relationship among different surfaces analyzed. diurnal trend in surface temperature of surface types, marl, dark sand, light sand, salt-affected soil, soul at 10 c...

During a field campaign covering the 2002 corn growing season, a dual polarized tower mounted L-band (1.4 GHz) radiometer (LRAD) provided brightness temperature (T(B)) measurements at preset intervals, incidence and azimuth angles. These radiometer measurements were supported by an extensive characterization of land surface variables including soil moisture, soil temperature, vegetation biomass...

Fertilized soils have large potential for production of soil nitrogen oxide (NOx=NO+NO2), however these emissions are difficult to predict in high-temperature environments. Understanding these emissions may improve air quality modelling as NOx contributes to formation of tropospheric ozone (O3), a powerful air pollutant. Here we identify the environmental and management factors that regulate so...

[1] Permafrost soils store nearly half of global soil carbon (C), and therefore permafrost thawing could lead to large amounts of greenhouse gas emissions via decomposition of soil organic matter. When ice-rich permafrost thaws, it creates a localized surface subsidence called thermokarst terrain, which changes the soil microenvironment. We used soil profile CO2 measurements to understand the r...

A box model for estimating bidirectional air– surface exchange of gaseous elemental mercury (Hg0) has been updated based on the latest understanding of the resistance scheme of atmosphere–biosphere interface transfer. Simulations were performed for two seasonal months to evaluate diurnal and seasonal variation. The base-case results show that water and soil surfaces are net sources, while veget...

Chemical and microbial degradation of the nematicides-insecticides aldicarb and ethoprop has been studied extensively in both laboratory and field studies. These studies show that temperature is the most important variable affecting the degradation rate of aldicarb and its carbamate metabolites in surface soils. Temperature and organic matter appear to be the most important variables affecting ...

1. INTRODUCTION Deardorff (1978, D78 henceforth) showed that a two-layered force-restore scheme is superior to bulk scheme in describing the surface soil moisture content because it contains the mechanism by which a deeper soil layer can influence the thin surface layer. This gives the flexibility and advantages in superficial soil moisture prediction especially when there are precipitation and...