This paper presents projections of climate extremes over China under global warming of 1.5,2,and 3℃ above pre-industrial(1861–1900),based on the latest Coupled Model Intercomparison Project phase 6(CMIP6)simulations...This paper presents projections of climate extremes over China under global warming of 1.5,2,and 3℃ above pre-industrial(1861–1900),based on the latest Coupled Model Intercomparison Project phase 6(CMIP6)simulations.Results are compared with what produced by the precedent phase of the project,CMIP5.Model evaluation for the reference period(1985–2005)indicates that CMIP6 models outperform their predecessors in CMIP5,especially in simulating precipitation extremes.Areal averages for changes of most indices are found larger in CMIP6 than in CMIP5.The emblematic annual mean temperature,when averaged over the whole of China in CMIP6,increases by 1.49,2.21,and 3.53℃(relative to1985–2005)for 1.5,2,and 3℃ above-preindustrial global warming levels,while the counterpart in CMIP5 is 1.20,1.93 and 3.39℃ respectively.Similarly,total precipitation increases by 5.3%,8.6%,and16.3%in CMIP6 and by 4.4%,7.0%and 12.8%in CMIP5,respectively.The spatial distribution of changes for extreme indices is generally consistent in both CMIP5 and CMIP6,but with significantly higher increases in CMIP6 over Northeast and Northwest China for the hottest day temperature,and South China for the coldest night temperature.In the south bank of the Yangtze River,and most regions around40°N,CMIP6 shows higher increases for both total precipitation and heavy precipitation.The projected difference between CMIP6 and CMIP5 is mainly attributable to the physical upgrading of climate models and largely independent from their emission scenarios.展开更多
Based on observations of the equilibrium line altitude(ELA)of the Qiyi Glacier in the Qilian Mountain,we established a statistical model between ELA and its major influencing factors,warm season air temperature(air te...Based on observations of the equilibrium line altitude(ELA)of the Qiyi Glacier in the Qilian Mountain,we established a statistical model between ELA and its major influencing factors,warm season air temperature(air temperature averages for September,July and August)and cold season precipitation(total precipitation in the period January through March).Warm season air temperature was the leading climatic factor influencing ELA variations.The glacier ELA ascends(descends)172 m when warm season air temperature increases(decreases)by 1°C,and ascends(descends)62 m when cold season precipitation decreases(increases)by 10%.In the period 1958-2008,the glacier ELA showed a general increasing trend,ascending 230 m and reaching its highest altitude in 2006 at 5131 m a.s.l.,close to the glacier summit.If future climate is similar to that in the period 2001-2008,the Qiyi Glacier will not stabilize until it retreats by 2.08 km.展开更多
Clustered heavy rains （CHRs） defined using hierarchical cluster analysis based on daily observations of precipitation in China during 1960-2008 are investi- gated in this paper. The geographical pattern of CHRs in C...Clustered heavy rains （CHRs） defined using hierarchical cluster analysis based on daily observations of precipitation in China during 1960-2008 are investi- gated in this paper. The geographical pattern of CHRs in China shows three high-frequency centers--South China, the Yangtze River basin, and part of North China around the Bohai Sea. CHRs occur most frequently in South China with a mean annual frequency of 6.8 （a total of 334 times during 1960-2008）. June has the highest monthly frequency （2.2 times/month with a total of 108 times dur- ing 1960-2008）, partly in association with the Meiyu phenomenon in the Yangtze River basin. Within the past 50 years, the frequency of CHRs in China has increased significantly from 13.5 to 17.3 times per year, which is approximately 28%. In the 1990s, the frequency of CHRs often reached 19.1 times per year. The geographical extent of CHR has expanded slightly by 0.5 stations, and its average daily rainfall intensity has increased by 3.7 mm d-1. The contribution of CHRs to total rainfall amount and the frequency of daily precipitation have increased by 63.1% and 22.7%, respectively, partly due to a significant decrease in light rains. In drying regions of North and Northeast China, the amounts of minimal CHRs have had no significant trend in recent years, probably due to warming in these arid regions enhancing atmospheric conveetivity at individual stations.展开更多
Using daily precipitation data from weather stations in China, the variations in the contribution of extreme precipitation to the total precipitation are analyzed. It is found that extreme precipitation accounts for a...Using daily precipitation data from weather stations in China, the variations in the contribution of extreme precipitation to the total precipitation are analyzed. It is found that extreme precipitation accounts for approximately one third of the total precipitation based on the overall mean for China. Over the past half century, extreme precipitation has played a dominant role in the year-to-year variability of the total precipitation. On the decadal time scale, the extreme precipitation makes different contributions to the wetting and drying regions of China. The wetting trends of particular regions are mainly attributed to increases in extreme precipitation; in contrast, the drying trends of other regions are mainly due to decreases in non-extreme precipitation.展开更多
Based on 10 years precipitation data from Tropical Rainfall Measurement Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） 3B42 and the best track data from China Meteorological Administration （CMA）, t...Based on 10 years precipitation data from Tropical Rainfall Measurement Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） 3B42 and the best track data from China Meteorological Administration （CMA）, the seasonal, monthly and annual contribution of tropical cyclone （TC） precipitation to the total rainfall are analyzed over the Western North Pacific （WNP） during 1998 to 2007 from May to December. The results show that： （1） TC seasonal rainfall contribution ranges from 4% in inland regions to above 40% in ocean-regions of 15°N-25°N. TCs at higher categories contribute much more to the total precipitation. （2） On monthly scale, TCs contribute 60% to the total rainfall regionally during whole TC season, which is the maximum contribution. The peak contribution of TC rainfall averaged in multi-months of the ten years occurs in August （28%） over the whole ocean impacted by TC and in December （23%） over the whole land impacted by TC, respectively. （3） On annual scale, the maximum contribution of TC precipitation to the total rainfall are in 2004 （-30%） over ocean and in 1998 （-20%） over land, respectively. （4） The contribution of TC precipitation to the total rainfall increases 6% （decreases 6%） in El Nino （La Nifia） years compared with neutral years.展开更多
基金supported by the National Key Research and Development Program of China(2017YFA0603804,2016YFA0600402,and 2018YFC1507704)。
文摘This paper presents projections of climate extremes over China under global warming of 1.5,2,and 3℃ above pre-industrial(1861–1900),based on the latest Coupled Model Intercomparison Project phase 6(CMIP6)simulations.Results are compared with what produced by the precedent phase of the project,CMIP5.Model evaluation for the reference period(1985–2005)indicates that CMIP6 models outperform their predecessors in CMIP5,especially in simulating precipitation extremes.Areal averages for changes of most indices are found larger in CMIP6 than in CMIP5.The emblematic annual mean temperature,when averaged over the whole of China in CMIP6,increases by 1.49,2.21,and 3.53℃(relative to1985–2005)for 1.5,2,and 3℃ above-preindustrial global warming levels,while the counterpart in CMIP5 is 1.20,1.93 and 3.39℃ respectively.Similarly,total precipitation increases by 5.3%,8.6%,and16.3%in CMIP6 and by 4.4%,7.0%and 12.8%in CMIP5,respectively.The spatial distribution of changes for extreme indices is generally consistent in both CMIP5 and CMIP6,but with significantly higher increases in CMIP6 over Northeast and Northwest China for the hottest day temperature,and South China for the coldest night temperature.In the south bank of the Yangtze River,and most regions around40°N,CMIP6 shows higher increases for both total precipitation and heavy precipitation.The projected difference between CMIP6 and CMIP5 is mainly attributable to the physical upgrading of climate models and largely independent from their emission scenarios.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(KZCX2-YW-310)the National Basic Research Program of China(2005CB422003)+1 种基金the National Natural Science Foundation of China(40930526)the Special Program of the Ministry of Science and Technology of the People's Republic of China for Basic Works(2006FY1102007)
文摘Based on observations of the equilibrium line altitude(ELA)of the Qiyi Glacier in the Qilian Mountain,we established a statistical model between ELA and its major influencing factors,warm season air temperature(air temperature averages for September,July and August)and cold season precipitation(total precipitation in the period January through March).Warm season air temperature was the leading climatic factor influencing ELA variations.The glacier ELA ascends(descends)172 m when warm season air temperature increases(decreases)by 1°C,and ascends(descends)62 m when cold season precipitation decreases(increases)by 10%.In the period 1958-2008,the glacier ELA showed a general increasing trend,ascending 230 m and reaching its highest altitude in 2006 at 5131 m a.s.l.,close to the glacier summit.If future climate is similar to that in the period 2001-2008,the Qiyi Glacier will not stabilize until it retreats by 2.08 km.
基金supported by the NationalBasic Research Program of China (Grant No. 2009CB421401)the Chinese Meteorological Administration Program (Grant No.GYHY200906009)
文摘Clustered heavy rains （CHRs） defined using hierarchical cluster analysis based on daily observations of precipitation in China during 1960-2008 are investi- gated in this paper. The geographical pattern of CHRs in China shows three high-frequency centers--South China, the Yangtze River basin, and part of North China around the Bohai Sea. CHRs occur most frequently in South China with a mean annual frequency of 6.8 （a total of 334 times during 1960-2008）. June has the highest monthly frequency （2.2 times/month with a total of 108 times dur- ing 1960-2008）, partly in association with the Meiyu phenomenon in the Yangtze River basin. Within the past 50 years, the frequency of CHRs in China has increased significantly from 13.5 to 17.3 times per year, which is approximately 28%. In the 1990s, the frequency of CHRs often reached 19.1 times per year. The geographical extent of CHR has expanded slightly by 0.5 stations, and its average daily rainfall intensity has increased by 3.7 mm d-1. The contribution of CHRs to total rainfall amount and the frequency of daily precipitation have increased by 63.1% and 22.7%, respectively, partly due to a significant decrease in light rains. In drying regions of North and Northeast China, the amounts of minimal CHRs have had no significant trend in recent years, probably due to warming in these arid regions enhancing atmospheric conveetivity at individual stations.
基金supported by the"Strategic Priority Research Program-Climate Change:Carbon Budget and Relevant Issues" of the Chinese Academy of Sciences(Grant No. XDA05090306)the National Basic Research Programof China(Grant No.2009CB421406)the Chinese Academy of Sciences-Common wealth Scientific and Industrial Research Organisation Cooperative Research Program(Grant No.GJHZ1223)
文摘Using daily precipitation data from weather stations in China, the variations in the contribution of extreme precipitation to the total precipitation are analyzed. It is found that extreme precipitation accounts for approximately one third of the total precipitation based on the overall mean for China. Over the past half century, extreme precipitation has played a dominant role in the year-to-year variability of the total precipitation. On the decadal time scale, the extreme precipitation makes different contributions to the wetting and drying regions of China. The wetting trends of particular regions are mainly attributed to increases in extreme precipitation; in contrast, the drying trends of other regions are mainly due to decreases in non-extreme precipitation.
基金supported by the Special Funds for Public Welfare of China(Grant No.GYHY201306077)CAS Strategic Priority Research Program(Grant No.XDA05100303)+1 种基金the National Natural Science Foundation of China(Grant Nos.41230419,91337213)the Jiangsu Provincial 2011 Program(Collaborative Innovation Center of Climate Change)
文摘Based on 10 years precipitation data from Tropical Rainfall Measurement Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） 3B42 and the best track data from China Meteorological Administration （CMA）, the seasonal, monthly and annual contribution of tropical cyclone （TC） precipitation to the total rainfall are analyzed over the Western North Pacific （WNP） during 1998 to 2007 from May to December. The results show that： （1） TC seasonal rainfall contribution ranges from 4% in inland regions to above 40% in ocean-regions of 15°N-25°N. TCs at higher categories contribute much more to the total precipitation. （2） On monthly scale, TCs contribute 60% to the total rainfall regionally during whole TC season, which is the maximum contribution. The peak contribution of TC rainfall averaged in multi-months of the ten years occurs in August （28%） over the whole ocean impacted by TC and in December （23%） over the whole land impacted by TC, respectively. （3） On annual scale, the maximum contribution of TC precipitation to the total rainfall are in 2004 （-30%） over ocean and in 1998 （-20%） over land, respectively. （4） The contribution of TC precipitation to the total rainfall increases 6% （decreases 6%） in El Nino （La Nifia） years compared with neutral years.
