末次盛冰期冰盖对全球季风活动的非对称性影响
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摘要
将新研发的南京信息工程大学地球系统模式(NUIST Earth System Model version 1,NESM1)首次应用于古气候模拟中,在Paleoclmate Modelling Intercomparison Project Phase III(PMIP3)框架下设计了工业革命前(Pre-industrial,PI)、末次盛冰期(Last Glacial Maximum,LGM)和增加大陆冰盖(Ice sheets,IS)试验,验证了模式对工业革命前气候和LGM时期气候的模拟能力,并通过增加大陆冰盖试验分析了其对全球季风活动的非对称性影响。结果表明:与PI时期相比,LGM时期的温度和降水均有显著改变。其中,全球平均温度比PI时期降低了4.7℃,全球平均降水减少了0.3 mm·d~(-1),降水对温度变化的敏感性约2.3%·℃~(-1),这与其他耦合模式结果一致。末次盛冰期大陆冰盖对其气候变化有重要贡献,冰盖引起的地表反照率改变与地形抬升作用导致全球平均气温下降1.2℃,降水量减少0.06 mm·d~(-1)。进一步分析表明,末次盛冰期冰盖对全球气候的影响还具有显著南北半球差异,所导致的温度降低和降水减少主要集中在北半球,其中北半球的降温更是高达南半球的5倍;引起北半球季风区年平均降水减少0.24 mm·d~(-1),降水年较差减小0.34 mm·d~(-1),而南半球变化很小。这是由于北半球大幅降温导致的低层水汽含量减小,并与大陆冰盖引起的欧洲大陆和北美大陆反气旋环流共同作用而影响季风活动。在夏季,减少的低层水汽含量与减弱的季风环流使夏季降水显著减少;而在冬季,加强的季风环流能部分抵消水汽含量减小的作用,故冬季降水稍微减弱。此外,在欧洲大陆和北美大陆附近对流层低层反气旋环流作用下,导致亚欧和北美季风活动区域减小。
The first attempt was made to simulate the paleoclimate by using the newly developed NUIST Earth System model version 1( NESM1). Three experiments are designed in the framework of Paleoclimate Model Intercomparison Project Phase III( PMIP3) : Pre Industry( PI),Last Glacial Maximum( LGM),and Ice Sheets( IS) experiments to verify the model's capability. IS experiment is used to investigate the asymmetric impact of LGM ice sheets on global monsoon activity. Results indicate that the NESM1 model is good enough to explain the cool and dry climate during the LGM period with a global cooling of 4. 7 ℃,a decreasing precipitation amount by 0. 3 mm·d~(-1)and the 2. 3%·℃~(-1)sensitivity of precipitation to surface air temperature( SAT) change,which is consistent with the previous studies. The LGM ice sheets play an important role in the formation of cool and dry LGM climate,which caused the global mean SAT to decrease by 1. 2 ℃ and global mean precipitation by 0. 06 mm·d~(-1). Further investigation demonstrates that the climate impacts' asymmetry of ice sheets are on Northern Hemisphere( NH)and Southern Hemisphere( SH). The significant cooling is only shown in NH,which is 5 times as largeas in the SH. The mean monsoon precipitation and annual range are reduced by 0. 24 mm·d~(-1)and 0. 34 mm·d~(-1),respectively,over the NH monsoon region,while the changes in SH monsoon region are not obvious. There are two factors contributing to these changes,including the lower specific humidity caused by the decreasing air temperature and the changed large-scale circulation owing to the existence of ice sheets over the North Europe and North American. The dramatically decreasing summer monsoon rainfall is associated with the decreasing specific humidity and weakening summer monsoon circulation,while the marginal change of winter monsoon precipitation is due to the cancellation effect between decreasing water vapor content and enhancing winter monsoon circulation. The anti-cyclonic circulation around the ice sheets can also reduce the Asian and North America monsoon domain.
The first attempt was made to simulate the paleoclimate by using the newly developed NUIST Earth System model version 1( NESM1). Three experiments are designed in the framework of Paleoclimate Model Intercomparison Project Phase III( PMIP3) : Pre Industry( PI),Last Glacial Maximum( LGM),and Ice Sheets( IS) experiments to verify the model's capability. IS experiment is used to investigate the asymmetric impact of LGM ice sheets on global monsoon activity. Results indicate that the NESM1 model is good enough to explain the cool and dry climate during the LGM period with a global cooling of 4. 7 ℃,a decreasing precipitation amount by 0. 3 mm·d~(-1)and the 2. 3%·℃~(-1)sensitivity of precipitation to surface air temperature( SAT) change,which is consistent with the previous studies. The LGM ice sheets play an important role in the formation of cool and dry LGM climate,which caused the global mean SAT to decrease by 1. 2 ℃ and global mean precipitation by 0. 06 mm·d~(-1). Further investigation demonstrates that the climate impacts' asymmetry of ice sheets are on Northern Hemisphere( NH)and Southern Hemisphere( SH). The significant cooling is only shown in NH,which is 5 times as largeas in the SH. The mean monsoon precipitation and annual range are reduced by 0. 24 mm·d~(-1)and 0. 34 mm·d~(-1),respectively,over the NH monsoon region,while the changes in SH monsoon region are not obvious. There are two factors contributing to these changes,including the lower specific humidity caused by the decreasing air temperature and the changed large-scale circulation owing to the existence of ice sheets over the North Europe and North American. The dramatically decreasing summer monsoon rainfall is associated with the decreasing specific humidity and weakening summer monsoon circulation,while the marginal change of winter monsoon precipitation is due to the cancellation effect between decreasing water vapor content and enhancing winter monsoon circulation. The anti-cyclonic circulation around the ice sheets can also reduce the Asian and North America monsoon domain.
引文
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[6]MARGO Project Members.Constraints on the magnitude and patterns of ocean cooling at the last glacial maximum.Nat.Geosci.,2009,2:127-132.
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[19]Di Nezio P N,Tierney J E.The effect of sea level on glacial IndoPacific climate.Nat.Geosci.,2013,6:485-491.doi:10.1038/ngeo1823.
[20]LIU Jian,WANG Bin,Yim S-Y,et al.What drives the global summer monsoon over the past millennium?Climate Dyn.,2012,39(5):1063-1072.doi:10.1007/s00382-012-1360-x.
[21]Lee J-Y,WANG Bin.Future change of global monsoon in the CMIP5.Climate Dyn.,2014,42(1/2):101-119.
[22]Broccoli A J,Manabe S.The influence of continental ice,atmospheric CO2,and land albedo on the climate of the last glacial maximum.Climate Dyn.,1987,1(2):87-99.
[23]Manabe S,Broccoli A J.The influence of continental ice sheets on the climate of an ice age.J.Geophys.Res.,1985,90(D1):2167-2190.
[24]Pollard D,Thompson S L.Climate and ice-sheet mass balance at the last glacial maximum from the GENESIS version 2 global climate model.Quat.Sci.Rev.,1998,16(8):841-863.
[25]CAO Jian,WANG Bin,XIANG Baoqiang,et al.Major modes of short-term climate variability in the newly developed NUIST earth system Model(NESM).Adv.Atmos.Sci.,2015,32(5):585-600.
[26]Roeckner E,Bauml G,Bonaventura L,et al.The atmospheric general circulation model ECHAM5.Part I:model description.Rep.No.349,Max-Planck-Institutfür Meteorologie,Hamburg,Germany,2003:127.
[27]Madec G,and the NEMO team,NEMO ocean engine.Note du pòle de modélisation,Institut Pierre-Simon Laplace(IPSL),France,No 27ISSN No 1288-1619,2012.
[28]Hunke E C,Lipscomb W H.CICE:the Los Alamos Sea Ice model documentation and software user's manual,version 4.1.LA-CC-06-012,Los Alamos National Laboratory,Los Alamos N.M.,2010.
[29]Taylor K E,Stouffer R J,Meehl G A.An overview of CMIP5 and the experiment design.Bull.Amer.Meteor.Soc.,2012,93:485-498.
[30]Peltier W R.Closure of the budget of global sea level rise over the GRACE era:the importance and magnitudes of the required corrections for global glacial isostatic adjustment.Quat.Sci.Rev.,2009,28(17/18):1658-1674.
[31]Kageyama M,Braconnot P,Bopp L,et al.Mid-Holocene and last glacial maximum climate simulations with the IPSL model:Part II:model-data comparisons.Climate Dyn.,2012,40(9/10):2469-2495.
[32]Huffman G J,Adler R F,Bolvin D T,et al.Improving the global precipitation record:GPCP Version 2.1.Geophys.Res.Lett.,2009,36(17):L17808.doi:10.1029/2009GL040000.
[33]Xie P P,Arkin P A.Global precipitation:a 17-year monthly analysis based on gauge observations,satellite estimates,and numerical model outputs.Bull.Amer.Meteor.Soc.,1997,78:2539-2558.
[34]Annamalai H,Hamilton K,Sperber K R.The South Asian summer monsoon and its relationship with ENSO in the IPCC AR4 simulations.J.Climate,2007,20(6):1071-1092.
[35]徐敏,于庚康,徐经纬,等.不同分辨率下全球气候模式的集合结果检验.气象科学,2013,33(2):160-167.XU Min,YU Gengkang,XU Jingwei,et al.Assessment of global climate models based on different resolution sets of simulation results.Journal of the Meteorological Sciences(in Chinese),2013,33(2):160-167.
[36]张宏芳,陈海山.21个气候模式对东亚夏季环流模拟的评估II:年际变化.气象科学,2011,31(3):247-257.ZHANG Hongfang,CHEN Haishan.Evaluation of summer circulation simulation over East Asia by 21 climate models II:Interannual variability.Journal of the Meteorological Sciences(in Chinese),2011,31(3):247-257.
[37]WANG B,DING Q.The global monsoon:Major modes of annual variations in the tropics.Dyn.Atmos.Ocean,2008,2:165-183.doi:10.1016/j.dynatmoce.5.002.
[38]WANG Bin,Kim H-J,Kikuchik,et al.Diagnostic metrics for evaluation of annual and diurnal cycles.Climate Dyn.,2011,37(5/6):941-955.
[39]林壬萍,周天军,薛峰,等.NCEP/NCAR再分析资料所揭示的全球季风降水变化.大气科学,2012,36(5):1027-1040.LIN Renping,ZHOU Tianjun,XUE Feng,et al.The global monsoon variability revealed by NCEP/NCAR reanalysis data.Chinese Journal of Atmospheric Sciences(in Chinese),2012,36(5):1027-1040.
[40]LIN Jialin.The double-ITCZ problem in IPCC AR4 coupled GCMs:ocean-atmosphere feedback analysis.J.Climate,2007,20(18):4497-4525.
[41]Delworth T L,Broccoli A J,Rosati A,et al.GFDL's CM2 global coupled climate models.Part I:formulation and simulation characteristics.J.Climate,2006,19(5):643-674.
[42]Hsu P-C,LI T,Murakami H,et al.Future change of the global monsoon revealed from 19 cmip5 models.J.Geophys.Res.,2013,118(3):1247-1260.
[43]Weaver A J,Eby M,Fanning A F,et al.Simulated influence of carbon dioxide,orbital forcing,and ice sheets on the climate of the last glacial maximum.Nature,1998,394(6696):847-853.
[44]Brady E C,Otto-Bliesner B L,Kay J E,et al.Sensitivity to glacial forcing in the CCSM4.J.Climate,2013,26(6):1901-1925.
[45]Toracinta E R,Oglesby R J,Bromwich D H.Atmospheric response to modified CLIMAP ocean boundary conditions during the last glacial maximum.J.Climate,2004,17:504-522.
[2]ZHENG Weipeng,YU Yongqiang.Paleoclimate simulations of the mid-Holocene and last glacial maximum by FGOALS.Adv.Atmos.Sci.,2013,30(3):684-698.
[3]Sueyoshi T,Ohgaito R,Yamamoto A,et al.Set-up of the PMIP3paleoclimate experiments conducted using an earth system model,MIROC-ESM.Geosci.Model Dev.,2013,6:819-836.
[4]Clark P U,Dyke A S,Shakun J D,et al.The last glacial maximum.Science,2009,325(5941):710-714.
[5]CLIMAP Project Members.Seasonal reconstructions of the earth's surface at the last glacial maximum.Geol.Soc.Amer.,Map Chart Series,1981,36:18.
[6]MARGO Project Members.Constraints on the magnitude and patterns of ocean cooling at the last glacial maximum.Nat.Geosci.,2009,2:127-132.
[7]Lain e'A,Kageyama M,Salas-Mélia D,et al.Northern hemisphere storm tracks during the last glacial maximum in the PMIP2 oceanatmosphere coupled models:energetic study,seasonal cycle,precipitation.Climate Dyn.,2009,32(5):593-614.
[8]Braconnot P,Otto-Bliesner S,Harrison S,at al.Results of PMIP2coupled simulations of the mid-Holocene and last glacial maximum—Part 1:experiments and large-scale features.Clim.Past,2007,3(2):261-277.
[9]Braconnot P,Otto-Bliesner S,Harrison S,at al.Results of PMIP2coupled simulations of the mid-Holocene and last glacial maximum—Part 2:feedbacks with emphasis on the location of the ITCZ and mid-and high latitudes heat budget.Clim.Past,2007,3(2):279-296.
[10]YAN M,WANG B,LIU J.Global monsoon change during Last Glacial Maximum:A multi-model study.Submitted to Climate Dynamics,2015.
[11]Kutzbach J E,Guetter P J.The influence of changing orbital parameters and surface boundary conditions on climate simulation for the past 18 000 years.J.Atmos.Sci.,1986,43:1726-1759.
[12]于革,陈星,刘健,等.末次盛冰期东亚气候的模拟和诊断初探.科学通报,2000,45(20):2153-2159.YU Ge,CHEN Xing,LIU Jian,et al.Preliminary study on LGM climate Simulation and the diagnosis for East Asia.Chinese Science Bulletin(in Chinese),2001,46(5):364-368.
[13]赵平,陈隆勋,周秀骥,等.末次盛冰期东亚气候的数值模拟.中国科学(D辑),2003,33(6):557-562.ZHAO Ping,CHEN Longxun,ZHOU Xiuji,et al.Modeling of the East Asian Climate during the Last Glacial Maximum.Science in China(Series D)(in Chinese),2003,46(10):1060-1068.
[14]JIANG Dabang,LANG Xianmei.Last glacial maximum East Asian monsoon:results of PMIP simulations.J.Climate,2010,23(18):5030-5038.
[15]Braconnot P,Harrison S P,Kageyam M,et al.Evaluation of climate models using palaeoclimatic data.Nat.Clim.Change,2012,2:417-424.
[16]Kageyama M,Braconnot P,Bopp L,et al.Mid-Holocene and last glacial maximum climate simulations with the IPSL model—Part I:comparing IPSL_CM5A to IPSL_CM4.Climate Dyn.,2012,40(9/10):2447-2468.
[17]黄刚,屈侠.IPCC AR4模式中夏季西太平洋副高南北位置特征的模拟.大气科学学报,2009,32(3):351-359.HUANG Gang,QU Xia.Merdional location of West Pacific subtropical high in summer in IPCC AR4 simulation.Transactions of Atmospheric Sciences(in Chinese),2009,32(3):351-359.
[18]胡伯彦,汤剑平,王淑瑜.中国地区IPCC A1B情景下21世纪中期气候变化的数值模拟试验.气象科学,2012,32(2):127-136.HU Boyan,TANG Jianping,WANG Shuyu.A numerical simulation for mid-21st century climate change over China under IPCC A1B scenario.Journal of the Meteorological Sciences(in Chinese),2012,32(2):127-136.
[19]Di Nezio P N,Tierney J E.The effect of sea level on glacial IndoPacific climate.Nat.Geosci.,2013,6:485-491.doi:10.1038/ngeo1823.
[20]LIU Jian,WANG Bin,Yim S-Y,et al.What drives the global summer monsoon over the past millennium?Climate Dyn.,2012,39(5):1063-1072.doi:10.1007/s00382-012-1360-x.
[21]Lee J-Y,WANG Bin.Future change of global monsoon in the CMIP5.Climate Dyn.,2014,42(1/2):101-119.
[22]Broccoli A J,Manabe S.The influence of continental ice,atmospheric CO2,and land albedo on the climate of the last glacial maximum.Climate Dyn.,1987,1(2):87-99.
[23]Manabe S,Broccoli A J.The influence of continental ice sheets on the climate of an ice age.J.Geophys.Res.,1985,90(D1):2167-2190.
[24]Pollard D,Thompson S L.Climate and ice-sheet mass balance at the last glacial maximum from the GENESIS version 2 global climate model.Quat.Sci.Rev.,1998,16(8):841-863.
[25]CAO Jian,WANG Bin,XIANG Baoqiang,et al.Major modes of short-term climate variability in the newly developed NUIST earth system Model(NESM).Adv.Atmos.Sci.,2015,32(5):585-600.
[26]Roeckner E,Bauml G,Bonaventura L,et al.The atmospheric general circulation model ECHAM5.Part I:model description.Rep.No.349,Max-Planck-Institutfür Meteorologie,Hamburg,Germany,2003:127.
[27]Madec G,and the NEMO team,NEMO ocean engine.Note du pòle de modélisation,Institut Pierre-Simon Laplace(IPSL),France,No 27ISSN No 1288-1619,2012.
[28]Hunke E C,Lipscomb W H.CICE:the Los Alamos Sea Ice model documentation and software user's manual,version 4.1.LA-CC-06-012,Los Alamos National Laboratory,Los Alamos N.M.,2010.
[29]Taylor K E,Stouffer R J,Meehl G A.An overview of CMIP5 and the experiment design.Bull.Amer.Meteor.Soc.,2012,93:485-498.
[30]Peltier W R.Closure of the budget of global sea level rise over the GRACE era:the importance and magnitudes of the required corrections for global glacial isostatic adjustment.Quat.Sci.Rev.,2009,28(17/18):1658-1674.
[31]Kageyama M,Braconnot P,Bopp L,et al.Mid-Holocene and last glacial maximum climate simulations with the IPSL model:Part II:model-data comparisons.Climate Dyn.,2012,40(9/10):2469-2495.
[32]Huffman G J,Adler R F,Bolvin D T,et al.Improving the global precipitation record:GPCP Version 2.1.Geophys.Res.Lett.,2009,36(17):L17808.doi:10.1029/2009GL040000.
[33]Xie P P,Arkin P A.Global precipitation:a 17-year monthly analysis based on gauge observations,satellite estimates,and numerical model outputs.Bull.Amer.Meteor.Soc.,1997,78:2539-2558.
[34]Annamalai H,Hamilton K,Sperber K R.The South Asian summer monsoon and its relationship with ENSO in the IPCC AR4 simulations.J.Climate,2007,20(6):1071-1092.
[35]徐敏,于庚康,徐经纬,等.不同分辨率下全球气候模式的集合结果检验.气象科学,2013,33(2):160-167.XU Min,YU Gengkang,XU Jingwei,et al.Assessment of global climate models based on different resolution sets of simulation results.Journal of the Meteorological Sciences(in Chinese),2013,33(2):160-167.
[36]张宏芳,陈海山.21个气候模式对东亚夏季环流模拟的评估II:年际变化.气象科学,2011,31(3):247-257.ZHANG Hongfang,CHEN Haishan.Evaluation of summer circulation simulation over East Asia by 21 climate models II:Interannual variability.Journal of the Meteorological Sciences(in Chinese),2011,31(3):247-257.
[37]WANG B,DING Q.The global monsoon:Major modes of annual variations in the tropics.Dyn.Atmos.Ocean,2008,2:165-183.doi:10.1016/j.dynatmoce.5.002.
[38]WANG Bin,Kim H-J,Kikuchik,et al.Diagnostic metrics for evaluation of annual and diurnal cycles.Climate Dyn.,2011,37(5/6):941-955.
[39]林壬萍,周天军,薛峰,等.NCEP/NCAR再分析资料所揭示的全球季风降水变化.大气科学,2012,36(5):1027-1040.LIN Renping,ZHOU Tianjun,XUE Feng,et al.The global monsoon variability revealed by NCEP/NCAR reanalysis data.Chinese Journal of Atmospheric Sciences(in Chinese),2012,36(5):1027-1040.
[40]LIN Jialin.The double-ITCZ problem in IPCC AR4 coupled GCMs:ocean-atmosphere feedback analysis.J.Climate,2007,20(18):4497-4525.
[41]Delworth T L,Broccoli A J,Rosati A,et al.GFDL's CM2 global coupled climate models.Part I:formulation and simulation characteristics.J.Climate,2006,19(5):643-674.
[42]Hsu P-C,LI T,Murakami H,et al.Future change of the global monsoon revealed from 19 cmip5 models.J.Geophys.Res.,2013,118(3):1247-1260.
[43]Weaver A J,Eby M,Fanning A F,et al.Simulated influence of carbon dioxide,orbital forcing,and ice sheets on the climate of the last glacial maximum.Nature,1998,394(6696):847-853.
[44]Brady E C,Otto-Bliesner B L,Kay J E,et al.Sensitivity to glacial forcing in the CCSM4.J.Climate,2013,26(6):1901-1925.
[45]Toracinta E R,Oglesby R J,Bromwich D H.Atmospheric response to modified CLIMAP ocean boundary conditions during the last glacial maximum.J.Climate,2004,17:504-522.