Global effects are due to changes in global cycles of C and N and water vapor and may be related to global warming or the greenhouse effect. The principal local effects of deforestation are related to changes in microclimate and soil properties. In general, deforestation eliminates the buffering effect of vegetation cover and accentuates the extremes. Deforestation decreases rainfall effectiveness and increases aridization of the climate. Forest removal increases the magnitude and intensity of net radiation reaching the soil surface.
Deforestation decreases the maximum relative humidity, especially during mid-day.
There is also a corresponding increase in air temperature and evaporation rate. Perhaps the most drastic effect of deforestation is on soil temperature. The maximum soil temperature at I to 5 cm depth can be 5 to 20 C higher on cleared land on a sunny day compared with land under TRF cover. Deforestation also has a drastic impact on the physical, chemical, and biological properties of soil. The magnitude of deforestation-induced alterations in soil properties depends on antecedent soil conditions, tree density and species of the forest and under story vegetation, and methods of lend clearing used.