为减少不同气候模式评估气溶胶气候效应的差异,第六次耦合模式比较计划(Coupled Model Intercomparison Project Phase 6,CMIP6)直接给定了人为气溶胶强迫数据。因此,有必要基于此强迫数据重新评估气溶胶气候效应。本研究首先将CMIP6给...为减少不同气候模式评估气溶胶气候效应的差异,第六次耦合模式比较计划(Coupled Model Intercomparison Project Phase 6,CMIP6)直接给定了人为气溶胶强迫数据。因此,有必要基于此强迫数据重新评估气溶胶气候效应。本研究首先将CMIP6给出的描述人为气溶胶强迫的模块引入南京信息工程大学(Nanjing University of Information Science and Technology,NUIST)的地球系统模式(The NUIST Earth System Model,NESM)。之后,利用NESM模式评估地球辐射收支平衡对此人为气溶胶强迫的响应,并分析模式模拟结果的不确定性。评估给出的人为气溶胶有效辐射强迫为-0.45(±0.28)W·m^-2。其中,气溶胶直接辐射效应为-0.34(±0.01)W·m^-2,与第二次气溶胶比较计划(The second phase of Aerosol Comparisons between Observations and Models,AeroComⅡ)的评估结果基本一致;气溶胶对云辐射强迫的影响(包括半直接效应和间接效应)为-0.10(±0.30)W·m^-2,明显受到模式内部变率的干扰,具有较大的不确定性。展开更多
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...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。展开更多
This paper introduces the experimental designs and outputs of the Diagnostic,Evaluation and Characterization of Klima(DECK),historical,Scenario Model Intercomparison Project(MIP),and Paleoclimate MIP(PMIP)experiments ...This paper introduces the experimental designs and outputs of the Diagnostic,Evaluation and Characterization of Klima(DECK),historical,Scenario Model Intercomparison Project(MIP),and Paleoclimate MIP(PMIP)experiments from the Nanjing University of Information Science and Technology Earth System Model version 3(NESM3).Results show that NESM3 reasonably simulates the modern climate and the major internal modes of climate variability.In the Scenario MIP experiment,changes in the projected surface air temperature(SAT)show robust“Northern Hemisphere(NH)warmer than Southern Hemisphere(SH)”and“land warmer than ocean”patterns,as well as an El Niño-like warming over the tropical Pacific.Changes in the projected precipitation exhibit“NH wetter than SH”and“eastern hemisphere gets wetter and western hemisphere gets drier”patterns over the tropics.These precipitation patterns are driven by circulation changes owing to the inhomogeneous warming patterns.Two PMIP experiments show enlarged seasonal cycles of SAT and precipitation over the NH due to the seasonal redistribution of solar radiation.Changes in the climatological mean SAT,precipitation,and ENSO amplitudes are consistent with the results from PMIP4 models.The NESM3 outputs are available on the Earth System Grid Federation nodes for data users.展开更多
To better understand the climate response under stabilized,overshoot,and transient global warming,four types of ensemble experiments on 1.5℃/2℃ global warming scenarios(i.e.,stabilized 1.5℃,1.5℃ overshoot,stabiliz...To better understand the climate response under stabilized,overshoot,and transient global warming,four types of ensemble experiments on 1.5℃/2℃ global warming scenarios(i.e.,stabilized 1.5℃,1.5℃ overshoot,stabilized 2℃,and transient 2℃)are elaborately designed using the Nanjing University Information Science and Technology Earth System Model(NESM).Compared with the modern climate(1985–2014),the projected surface air temperature(SAT)change is characterized by a robust‘Northern Hemisphere(NH)-warmer than-Southern Hemisphere(SH)’and‘land-warmer than-ocean’patterns.The projected precipitation change exhibits‘NH-wetter than-SH’pattern in the tropics.Although the response of SAT and precipitation climatology show similar pattern between stabilized and overshoot scenarios,some significant differences are still found.The projected change in the Northern Hemisphere land monsoon precipitation(NHLMP)is 30% larger in the transient 2℃ experiment compared with that in the stabilized 2℃ experiment.The more vigorous NHLMP in the transient global warming scenario is mainly due to the enhanced land-sea thermal contrast and interhemispheric temperature difference.The enlarged land-sea thermal contrast increases the surface pressure gradient between the NH continents and its adjacent oceans,thus enhancing the NH monsoon circulation and moisture convergence.The enhanced interhemispheric temperature difference shifts the Hadley circulation and intertropical convergence zone northward,leading to the enhanced moisture convergence and the shifts of tropical rain band over the NH monsoon region.This result highlights that climate responses may depend on different warming trajectories and,which could facilitate the strategic planning of governments.展开更多
文摘为减少不同气候模式评估气溶胶气候效应的差异,第六次耦合模式比较计划(Coupled Model Intercomparison Project Phase 6,CMIP6)直接给定了人为气溶胶强迫数据。因此,有必要基于此强迫数据重新评估气溶胶气候效应。本研究首先将CMIP6给出的描述人为气溶胶强迫的模块引入南京信息工程大学(Nanjing University of Information Science and Technology,NUIST)的地球系统模式(The NUIST Earth System Model,NESM)。之后,利用NESM模式评估地球辐射收支平衡对此人为气溶胶强迫的响应,并分析模式模拟结果的不确定性。评估给出的人为气溶胶有效辐射强迫为-0.45(±0.28)W·m^-2。其中,气溶胶直接辐射效应为-0.34(±0.01)W·m^-2,与第二次气溶胶比较计划(The second phase of Aerosol Comparisons between Observations and Models,AeroComⅡ)的评估结果基本一致;气溶胶对云辐射强迫的影响(包括半直接效应和间接效应)为-0.10(±0.30)W·m^-2,明显受到模式内部变率的干扰,具有较大的不确定性。
基金supported by the Natural Science Foundation of China of Jiangsu Province(Grant No.BK20180812,BK20181412)the National Natural Science Foundation of China(Grant No.42005017,41675072,41922033)the Startup Foundation for Introducing Talent of NUIST(Grant No.2018r063)。
文摘This paper introduces the experimental designs and outputs of the Diagnostic,Evaluation and Characterization of Klima(DECK),historical,Scenario Model Intercomparison Project(MIP),and Paleoclimate MIP(PMIP)experiments from the Nanjing University of Information Science and Technology Earth System Model version 3(NESM3).Results show that NESM3 reasonably simulates the modern climate and the major internal modes of climate variability.In the Scenario MIP experiment,changes in the projected surface air temperature(SAT)show robust“Northern Hemisphere(NH)warmer than Southern Hemisphere(SH)”and“land warmer than ocean”patterns,as well as an El Niño-like warming over the tropical Pacific.Changes in the projected precipitation exhibit“NH wetter than SH”and“eastern hemisphere gets wetter and western hemisphere gets drier”patterns over the tropics.These precipitation patterns are driven by circulation changes owing to the inhomogeneous warming patterns.Two PMIP experiments show enlarged seasonal cycles of SAT and precipitation over the NH due to the seasonal redistribution of solar radiation.Changes in the climatological mean SAT,precipitation,and ENSO amplitudes are consistent with the results from PMIP4 models.The NESM3 outputs are available on the Earth System Grid Federation nodes for data users.
基金supported by the National Key R&D Program of China(2017YFA0603801)the Natural Science Foundation of China of Jiangsu Province(BK20180812,BK20181412)the Natural Science Foundation of China(42005017,41922033).
文摘To better understand the climate response under stabilized,overshoot,and transient global warming,four types of ensemble experiments on 1.5℃/2℃ global warming scenarios(i.e.,stabilized 1.5℃,1.5℃ overshoot,stabilized 2℃,and transient 2℃)are elaborately designed using the Nanjing University Information Science and Technology Earth System Model(NESM).Compared with the modern climate(1985–2014),the projected surface air temperature(SAT)change is characterized by a robust‘Northern Hemisphere(NH)-warmer than-Southern Hemisphere(SH)’and‘land-warmer than-ocean’patterns.The projected precipitation change exhibits‘NH-wetter than-SH’pattern in the tropics.Although the response of SAT and precipitation climatology show similar pattern between stabilized and overshoot scenarios,some significant differences are still found.The projected change in the Northern Hemisphere land monsoon precipitation(NHLMP)is 30% larger in the transient 2℃ experiment compared with that in the stabilized 2℃ experiment.The more vigorous NHLMP in the transient global warming scenario is mainly due to the enhanced land-sea thermal contrast and interhemispheric temperature difference.The enlarged land-sea thermal contrast increases the surface pressure gradient between the NH continents and its adjacent oceans,thus enhancing the NH monsoon circulation and moisture convergence.The enhanced interhemispheric temperature difference shifts the Hadley circulation and intertropical convergence zone northward,leading to the enhanced moisture convergence and the shifts of tropical rain band over the NH monsoon region.This result highlights that climate responses may depend on different warming trajectories and,which could facilitate the strategic planning of governments.
