Shi lun wei lai ji duan qi hou shi jian fa zhan qu shi de bu que ding xing

Variations and trends in extreme climate events have recently received much attention since it is becoming more frequently and costly.Extreme climate events are happening on a certain time scale,being different from the abrupt climate change of climate system on the average state.The extreme climate events had happened at orbit scales and Millennial-Centennial scales,such as Paleocene-Eocene Thermal Maximum,the great warmth in Quaternary reflected by S4,S5 soils,and the severe dry-cold periods evidenced by the L9 and L15 at Chinese Loess Plateau,and the Younger Drays Event,the nine severe cold events respectively occurred in the last deglaciation and Holocene.These extreme climate events appeared in the earth′s climate system under the background of different changes in temperature,however,there are a lot of uncertainties in their formation mechanism and representation.Since the 20th century,many extreme climate events such as droughts,floods,hurricanes and dust storms have taken place,which could not be explained only by the increasing of greenhouse gas,and the conclusion that the frequency and intensity of extreme climate events would increase along with the global warming still remains uncertain.Therefore,it is neither scientific nor reasonable if we simply ascribe modern extreme climate events to climate warming.So,an intensive study for the volatility,periodicity and uncertainty of the extreme climate events happened at different time scales will help us to predict the development tendency of extreme climate events under the background of climate change in the future.