Research For Climate Change And Drought Characteristics In Inner Mongolia

Inner Mongolia covers a vast geographic area,extending from east to west.Its complex climate incorporates multi climate types.Inner Mongolia is a typical cold and arid region in northern China,which is an important ecological barrier in North China,and plays an important role in the ecological process.In recent years,with the gradual deepening of the impact of climate change,temperature,precipitation and other factors have changed greatly,the trend of drought is changing,which has a certain impact on the ecological environment,water resources,agriculture and animal husbandry production.The study of climatic factors and the characteristics and laws of drought can be used for reference in the construction of ecological environment and the development and utilization of water resources.This paper is based on the research of Inner Mongolia.It applies collected data of temperature and precipitation from 70 meteorological stations between 1951 and 2014.This paper also applies central clustering,climate tendency rate,Mann-Kendall test and standardized precipitation index and other methods to study the climatic factors change,abrupt temperature change and warming hiatus and characteristics and laws of climate drought.The main conclusions were as follows:1.In the study area,the annual(season)three kinds of temperature showed an upward trend,the average minimum temperature rising rate was faster than the average temperature and the average maximum temperature,the central area of the annual average minimum temperature rise rate was the fastest(0.442?/10a).Annual(season)three types of temperature in 1970s to 1990s showed a ladder shaped up.Obvious increase in spring and winter,in central area of average minimum temperature in winter the rising rate was fastest(0.537?/10a).The spatial variation of the three types of annual(season)temperature is decreased from west to east and from southeast to northwest.2.The annual precipitation in the study area is relatively large,but the overall trend is not obvious(east:-3.755mm/10a).Precipitation in different regions of the 70s to 90s has increased in varying degrees.Spring precipitation showed an increasing trend(central:1.583 mm/10a),and summer precipitation decreased(central:-5.495mm/10a),and there was no significant change in precipitation in autumn and winter.The spatial variation of annual(season)precipitation is incressed from west to east,from northwest to southeast.There was a negative correlation between annual precipitation and the three types of temperature,except for the individual stages of each annual(season),they were showed the change of the opposition.3.Among all types of temperature,the average minimum temperature of annual or season had mutaions between 1972 and 1993 firstly,average temperature followed it between 1973 and 1996,and average maximum temperature in the period of 1976 to 1998 after mutations.Summer changes the latest(90s)while winter changes the earliest(70s).Before and after abrupt temperature change,the average minimum temperature changes intensively.Before abrupt temperature change,all kinds of temperature in the spring and autumn and after abrupt temperature change in autumn contributes the most to temperature rising.4.In the years that temperature shifts happen early,warming stagnation appeared early accordingly.Three temperature types in spring of east region(1991)firstly exhibit warming stagnation and temperatures for autumn in all regions exhibit later(2006),summer partial region in 2006 shows warming stagnation.The average maximum temperature in the east region(0.412?/a)displayed the lowest rate of increase in the period after the abrupt temperature change and before stagnation and the highest rate of increase after warming stagnation.The average annual temperature in the west is opposite.Average temperature(2.634?/a)for spring in west area increased the fastest after change before stagnation while average maximum temperature(-2.118?/a)for autumn in central area dropped the fastest after stagnation.Various types of temperature change before the sudden change in different periods,and there were warming stagnation phenomenon of 7?20 years.5.Except for the annual,spring,autumn,winter in the west area and spring,autumn in the central and spring,winter in the east area the climate tends to be moist,the fastest rate of summer drought in Central area(-0.12/10a).The duration of drought in west and central showed a trend of shortening,and the intensity of drought decreased,and the other areas and scales were opposite,and increased with the increase of scale.In the eastern part of the scale of 12,the drought degree was the fastest(4.735/10a).Severe drought in Western 1960s,central and Eastern 1990s to 2000s.6.In the west area,the annual SPI from northwest to southeast and east area from south to north showed a downward trend.The fastest rate of drought in central area.The spatial variation of SPI in plant growth period was consistent with that of the annual,but rhe area of the west and central areas with obvious drought trend has expanded.In the west and east area,spring,autumn,winter and spring in the central area the drought rate is declining,the climate tends to wet,and other seasonal changes in the trend of drought.