Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesim...Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesimal method for different stations at first,then yearly EHT and ELT events were counted up in differ-ent stations,and the characteristics of their spatio-temporal distribution were diagnosed at last.The study drew follow-ing conclusions:1)The consistent anomaly distribution characteristic was the most important mode of the EHT and ELT events in Northwest China.2)The spatial distribution of the EHT and ELT events can be divided into five sub-regions,namely,the north of Qinghai and west of Gansu,the north of Xinjiang,the south of Xinjiang,the east of Northwest China and the south of Qinghai.3)The EHT events showed remarkable increasing trend in all of five sub-regions,but only in the north of Qinghai and west of Gansu area,sudden change phenomenon occurred;the ELT events showed decreasing trend in all of five sub-regions,and sudden change phenomenon occurred in Northwest China except for south of Qinghai.4)In all of five sub-regions the EHT events showed remarkable 12-14yr period os-cillation,and the ELT event showed significant 13-15yr and 7-8yr period oscillation.5)The EHT and ELT events displayed remarkable positive and negative responses to regional warming of Northwest China respectively.展开更多
Western China and central Asia are positioned centrally along the Millennium Silk Road,which is regarded as a core region bridging the East and the West.Understanding the potential changes in climate over this core re...Western China and central Asia are positioned centrally along the Millennium Silk Road,which is regarded as a core region bridging the East and the West.Understanding the potential changes in climate over this core region is important to the successful implementation of the so-called＇Belt and Road Initiative＇（a $1 trillion regional investment in infrastructure）.In this study,both mean and extreme climate changes are projected using the ensemble mean of CMIP5 models.The results show a warming of ～1.5,2.9,3.6,and 6.0 ℃ under RCP2.6,4.5,6.0,and 8.5,respectively,by the end of the twenty-first century,with respect to the 1986-2005 baseline period.Meanwhile,the annual mean precipitation amount increases consistently across all RCPs,with an increase by ～14% with respect to 1986-2005 under RCP8.5.The warming over the Millennium Silk Road region reaches 1.5 ℃ before 2020 under all the emission scenarios.The 2020s （2030s） see a 2 ℃ warming under the RCP8.5 （RCP4.5） scenario.Global warming that is 0.5 ℃ lower （i.e.a warming of 1.5 ℃） could result in the avoidance of otherwise significant impacts in the Silk Road core region-specifically,a further warming of 0.73 ℃ （with an interquartile range of 0.49%-0.94 ℃） and an increase in the number of extreme heat days by 4.2,at a cost of a reduced increase of 2.72% （0.47%-3.82%） in annual precipitation.The change in consecutive dry days is region-dependent展开更多
Based on the observation data from China coastal marine stations,the key indicators of marine climate along China coast were explored,including sea surface t emperature(SST),sea level and sea ice.Results show that:(a)...Based on the observation data from China coastal marine stations,the key indicators of marine climate along China coast were explored,including sea surface t emperature(SST),sea level and sea ice.Results show that:(a)The SST along China coast continues rising and increased by 0.25℃/decade during 1980-2019,the warming accelerated significantly after 2011 and it has been well above normal for five consecutive years since 2015.In 2019,the average SST along China coast was 1.1℃ higher than normal(with 1981-2010 taken as a reference period),ranking the highest since 1980.Besides,the SST extremes have been explored based on four long-term marine stations for the period 1960-2019.(b)Sea level along China coast continues to rise at an accelerated rate.The mean sea level rise rate along China Coast was about 2.4 mm/yr during 1960-2019,3.4 mm/yr during 1980-2019,and 3.9 mm/yr during 1993-2019,with significant regional differences.The relatively stronger sea level rise trends were observed along the coastal waters of the Bohai Bay,the Laizhou Bay,the Yangtze River Estuary,the Pearl River Estuary,and the Hainan Island,respectively.Besides,the extreme sea levels along China coast showed an obvious upward trend from 1980 to 2019.During this period,the annual rise rate of extreme high water level along China coast was 4.4 mm/yr,and had obvious regional characteristics,with the highest rate of 9.9 mm/yr observed at Yantai of Shandong Province,(c)The annual sea ice period and sea ice cover of the Bohai Sea(BS)decreased substantially during 1963-2019 by 0.7-1.3 days/yr and 45-59%/yr,respectively,and the decrease rate of ice cover is larger in the north than that in the south.2019 was the year of light icing.展开更多
The air temperature of Wuli,which is located in seasonal frozen ground zone,is rising by 13 ℃ yearly.This paper discusses the days that each ground layers' temperature lags behind the surface temperature in reach...The air temperature of Wuli,which is located in seasonal frozen ground zone,is rising by 13 ℃ yearly.This paper discusses the days that each ground layers' temperature lags behind the surface temperature in reaching extremum.The results were shown:The time of each ground layers' lagging days was increasing;the lagging day in warm season was longer than that in cold season;the growth rate of lagging days in warm season was 0.5 d/y,while the growth rate of lagging days in cold season was 0.7 d/y.展开更多
基金Under the auspices of National Natural Science Foundation of China (No. 40375032,No. 40675043)
文摘Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesimal method for different stations at first,then yearly EHT and ELT events were counted up in differ-ent stations,and the characteristics of their spatio-temporal distribution were diagnosed at last.The study drew follow-ing conclusions:1)The consistent anomaly distribution characteristic was the most important mode of the EHT and ELT events in Northwest China.2)The spatial distribution of the EHT and ELT events can be divided into five sub-regions,namely,the north of Qinghai and west of Gansu,the north of Xinjiang,the south of Xinjiang,the east of Northwest China and the south of Qinghai.3)The EHT events showed remarkable increasing trend in all of five sub-regions,but only in the north of Qinghai and west of Gansu area,sudden change phenomenon occurred;the ELT events showed decreasing trend in all of five sub-regions,and sudden change phenomenon occurred in Northwest China except for south of Qinghai.4)In all of five sub-regions the EHT events showed remarkable 12-14yr period os-cillation,and the ELT event showed significant 13-15yr and 7-8yr period oscillation.5)The EHT and ELT events displayed remarkable positive and negative responses to regional warming of Northwest China respectively.
基金supported by the National Natural Science Foundation of China[grant numbers 41330423,41420104006,and 41605057]
文摘Western China and central Asia are positioned centrally along the Millennium Silk Road,which is regarded as a core region bridging the East and the West.Understanding the potential changes in climate over this core region is important to the successful implementation of the so-called＇Belt and Road Initiative＇（a $1 trillion regional investment in infrastructure）.In this study,both mean and extreme climate changes are projected using the ensemble mean of CMIP5 models.The results show a warming of ～1.5,2.9,3.6,and 6.0 ℃ under RCP2.6,4.5,6.0,and 8.5,respectively,by the end of the twenty-first century,with respect to the 1986-2005 baseline period.Meanwhile,the annual mean precipitation amount increases consistently across all RCPs,with an increase by ～14% with respect to 1986-2005 under RCP8.5.The warming over the Millennium Silk Road region reaches 1.5 ℃ before 2020 under all the emission scenarios.The 2020s （2030s） see a 2 ℃ warming under the RCP8.5 （RCP4.5） scenario.Global warming that is 0.5 ℃ lower （i.e.a warming of 1.5 ℃） could result in the avoidance of otherwise significant impacts in the Silk Road core region-specifically,a further warming of 0.73 ℃ （with an interquartile range of 0.49%-0.94 ℃） and an increase in the number of extreme heat days by 4.2,at a cost of a reduced increase of 2.72% （0.47%-3.82%） in annual precipitation.The change in consecutive dry days is region-dependent
基金supported by the National Key Research and Development Program of China(NO.2016YFC1402610).
文摘Based on the observation data from China coastal marine stations,the key indicators of marine climate along China coast were explored,including sea surface t emperature(SST),sea level and sea ice.Results show that:(a)The SST along China coast continues rising and increased by 0.25℃/decade during 1980-2019,the warming accelerated significantly after 2011 and it has been well above normal for five consecutive years since 2015.In 2019,the average SST along China coast was 1.1℃ higher than normal(with 1981-2010 taken as a reference period),ranking the highest since 1980.Besides,the SST extremes have been explored based on four long-term marine stations for the period 1960-2019.(b)Sea level along China coast continues to rise at an accelerated rate.The mean sea level rise rate along China Coast was about 2.4 mm/yr during 1960-2019,3.4 mm/yr during 1980-2019,and 3.9 mm/yr during 1993-2019,with significant regional differences.The relatively stronger sea level rise trends were observed along the coastal waters of the Bohai Bay,the Laizhou Bay,the Yangtze River Estuary,the Pearl River Estuary,and the Hainan Island,respectively.Besides,the extreme sea levels along China coast showed an obvious upward trend from 1980 to 2019.During this period,the annual rise rate of extreme high water level along China coast was 4.4 mm/yr,and had obvious regional characteristics,with the highest rate of 9.9 mm/yr observed at Yantai of Shandong Province,(c)The annual sea ice period and sea ice cover of the Bohai Sea(BS)decreased substantially during 1963-2019 by 0.7-1.3 days/yr and 45-59%/yr,respectively,and the decrease rate of ice cover is larger in the north than that in the south.2019 was the year of light icing.
基金Supported by Pasture Industrialization Technology Research Integration and Application in Mountainous Areas of Guizhou([2014]6017)Phosphate Solubilizing Bacteria Bank Establishment and Phosphate Solubilization Mechanism of Pasture Rhizosphere in Mountainous Areas of Guizhou([2013]2152)
文摘The air temperature of Wuli,which is located in seasonal frozen ground zone,is rising by 13 ℃ yearly.This paper discusses the days that each ground layers' temperature lags behind the surface temperature in reaching extremum.The results were shown:The time of each ground layers' lagging days was increasing;the lagging day in warm season was longer than that in cold season;the growth rate of lagging days in warm season was 0.5 d/y,while the growth rate of lagging days in cold season was 0.7 d/y.
