Abstract:
The term “drought” is the natural disaster which is caused by large amount of evaporation due to long term of dryness and it affects the nature and social economy in bad ways like shortcoming of plants due to low moisture in the soil and lack of surface water resource. Drought can also be explained as it is the one kind of atmospheric disaster that can affect the pastoral cattle breeding and plant cover.
The research was done focusing the diverse drought amount and diverse extensional and periodic dispersion based on precipitation data of the Mongolian Altitude (Mongolia and Inner Mongolia Autonomous Region) of total of 31 years from 1980 to 2010 performed by 108 weather stations using method SPI as modeling the GAMMA dispersion function.
The estimation of SPI for the period of 31 years from 1980 to 2010 of Mongolian Altitude shows that the drought is mainly dispersed in spring and summer times in areas including Khangai range; Bulgan, Selenge, Uvurkhangai, Tuv provinces which are south parts of Khentii range; from Northeast to the west - cavity of Grand Lakes, Dornogobi, South gobi of Altai, Alshaa, Ordos; in the southeast – Tung Liao, Chi Feng cities. The most serious dispersion year was 1981 and the SPI was “-2.57” in certain section of area from west to southeast till Alshaa province. In the spring and fall times, the drought intensification was higher in areas from west-north to south-east and from north-east to the center.
The most serious drought year was 1980 and SPI was equal to -2.501 and disperse was through the areas of south-west including Gobi-Altai, Bayankhongor, Alshaa and south part of Khulunbuir.
This natural order is relative to dry climate of Mongolian Altitude as well as sparse vegetative cover and low precipitation in the regions of south-west and south parts regarding their parched and deserted condition. Mongolian Altitude exists covering wide range of land and several regions along latitude from north to south. It is relatively different as for the space, earth surface, thus the drought period and its frequency is also different.
Study for evaluation of drought has contained the drought affecting scope, duration and the level and drought disperse. Also it
has included drought condition in the research regions in the spring, fall and summer times.
