Temporal And Spatial Variation Characteristics Of Near-extreme Temperature Events In China Based On Generalized Near-extreme State Density

The events with their values near the extreme are near-extreme events.The generalized density of states is proposed that is defined as a probability density function.Based on the estimation of the generalized state density of near-extreme events,the parameters of the generalized state density of near-extreme temperature events are constructed with the temperature daily maximum data in summer and daily minimum data in winter 1961-2013 in China.According to the analyze of the single station Nanjing,the maximum probability density of occurrence about near-extreme temperature is marked as ???_max and the corresponding r of???_maxis marked as r_p,which indicates when the difference between near-extreme events andextreme events is r_p,the probability of occurrence is maximum.Then r_P is defined as the most probable intensity of near-extreme temperature events.???_max and r_p can show the crowding degree characteristics about near-extreme temperature events and can bring significant physical meanings in the practical application.The temporal and spatial characteristics of near-extreme temperature events in China from 1961 to 2013 were studied in this article and the main conclusions are as follows:?1?For Nanjing station in the summer,the probability of near-extreme high temperature events which is 33.15? is the largest.In winter,when the minimum daily temperature reaches-2.78? in Nanjing,the probability of extreme low temperature events is the largest.From the national perspective,the regional characteristics of the national distribution of the most probable strength of the generalized state density of the near-extremes and the maximum mean generalized density of states in summer and winter are more obvious than in spring and autumn.When the maximal daily temperature reaches the high-temperature threshold about 1?2.6 ?,the extreme high temperature events are most likely to occur at the next moment over the west of northwestern China,southwestern and southern China in summer.In winter,when the minimum daily temperature temperature is higher than the low-temperature threshold about 1.2?3.2 ?,the appropriate extreme low temperature warning signal should be given over the north and east of southwestern China and the west of southern China as soon as possible.?2?In summer,the most probable near-extreme high temperatures in western China and the southern part of China are more sensitive to global warming.The probability of the most probable near-extreme high temperature in the western region decreases with the climate states,the possibility of the southern region appears to be the most probable extreme high temperature is increasing and the increased range is gradually reduced.The most probable near-extreme high temperatures in the northeastern North China are relatively less responsive to global warming and the probability of the most probable extreme high temperatures is decreasing.In winter,the most near-extreme low temperatures in northeastern China are more sensitive to global warming,but the likelihood of the most extreme near-low temperatures is declining,while the most probable near-extremism in the southern region is less responsive to global warming,but the probability of the most probable extreme low temperature is increasing.?3?Whether in summer or winter,China's most recent near-extreme temperature is getting closer to extreme temperature thresholds over the past 60 years.In summer,the probability of occurrence of the most probable extreme high temperature events is decreasing,and in winter,the most probable near-extreme low temperature events are becoming more and more likely.?4?In summer,west of Northwest China,South China and south of Southwest China are easy to happen the extreme warming events when the most probable intensity of near-extreme warming temperature events p is[1.0,2.5]? and the maximum probability density of occurrence about near-extreme warming temperature ???_max is up to 44%.South China,south of Southwest China and Xizang are easy to occur extreme cooling events when the most probable intensity of near-extreme cooling temperature events r_p is[0.5,2.5]? and the maximum probability density of occurrence about near-extreme cooling temperature ???_maxis up to 34%.In winter,the warning information about extreme warming events should give to Southwest China when the most probable intensity of near-extreme warming temperature events r_p is[1,2]?and the maximum probability density of occurrence about near-extreme warming temperature?max is up to 32%.The warning information about extreme cooling events should give to Southwest China,South China and south of the Yangtze River when the most probable intensity of near-extreme cooling temperature events p is[1.0,4.0]?.Therefore,the maximum probability density of occurrence ???_maxand the most probable intensity r_p of near-extreme anomalies temperature events can give some early warning information for the coming extreme anomalies temperature events.