Comparative Analysis Of Climate Change Over The Mid-latitude Western And Eastern Eurasia

Utilizing daily precipitation and temperature data collected from 333 stations from 1961 to 2012,we comparatively analyzed the spatio-temporal changes in a series of climate variables,including precipitation?PRCP?,maximum temperature(T_max),minimum temperature(T_min),and daily temperature range?DTR?,between Western?WE?and Eastern Eurasia?EE?on both the annual and seasonal scales.In addition,we explored their relationships with large-scale atmospheric circulations,such as Arctic Oscillation?AO?,North Atlantic Oscillation?NAO?and El Ni?o-Southern Oscillation?ENSO?patterns.The major conclusions are summarized as follows.1)PRCP mainly exhibited increasing trends in northern WE and decreasing trends in southern WE,whereas PRCP in EE recorded an increase-decrease-increase trend from high to low latitudes.T_max and T_min significantly increased for almost all stations in WE and EE.DTR showed an increasing trend in most of stations in WE and an adverse trend was detected in EE.2)The increase of annual PRCP in WE?5.63 mm/decade?was higher than that in EE?0.13 mm/decade?.On the seasonal scale,the PRCP in WE recorded an opposite trend from EE,especially in summer.Both T_max and T_min recorded significant warming?p<0.05?in WE and EE on the seasonal and annual scales,especially in winter.DTR were increased in WE and decreased in EE on the seasonal and annual scales.In response to global climate change,the difference between the temperate marine climate and the temperate monsoon climate was larger in PRCP and smaller in T_min and DTR,but no obvious effect on T_max was detected over the past half century.3)As for PRCP,there was only one obvious abrupt change detected in summer PRCP in EE?around 1963?.It was indicated that summer was the most sensitive season of PRCP.The abrupt changes in T_min?around 1988?occurred earlier than those in T_max?around 1993?in both regions,suggesting that variations in T_min were more sensitive than those in T_max over mid-latitude Eurasia.On the seasonal scales,winter is the most sensitive season of temperature indices.4)Cycles were 2³ years and 10 years of annual PRCP in WE,whereas 3⁵years,15 years and more than 30 years circles were detected in EE.PRCP had 3⁵years circle on the seasonal scales;There were 3⁵ years and more than 30 years circles of T_max,T_min,and DTR in WE and 5 years circles in EE.And all the seasons had 3⁵ years circles.5)AO was the major large-scale atmospheric circulation affecting the changes of PRCP and temperature over WE and EE,next one was NAO and the smallest was ENSO.AO was negatively related to the PRCP but positively correlated with temperature indices(T_max,T_min,and DTR)in the study areas at seasonal and annual scales.