The Chinese Academy of Sciences(CAS)Flexible Global Ocean Atmosphere Land System(FGOALS-f3-L)model datasets prepared for the sixth phase of the Coupled Model Intercomparison Project(CMIP6)Global Monsoons Model Interco...The Chinese Academy of Sciences(CAS)Flexible Global Ocean Atmosphere Land System(FGOALS-f3-L)model datasets prepared for the sixth phase of the Coupled Model Intercomparison Project(CMIP6)Global Monsoons Model Intercomparison Project(GMMIP)Tier-1 and Tier-3 experiments are introduced in this paper,and the model descriptions,experimental design and model outputs are demonstrated.There are three simulations in Tier-1,with different initial states,and five simulations in Tier-3,with different topographies or surface thermal status.Specifically,Tier-3 contains four orographic perturbation experiments that remove the Tibetan Iranian Plateau,East African and Arabian Peninsula highlands,Sierra Madre,and Andes,and one thermal perturbation experiment that removes the surface sensible heating over the Tibetan Iranian Plateau and surrounding regions at altitudes above 500 m.These datasets will contribute to CMIP6’s value as a benchmark to evaluate the importance of long-term and short-term trends of the sea surface temperature in monsoon circulations and precipitation,and to a better understanding of the orographic impact on the global monsoon system over highlands.展开更多
The climate variability in global land precipitation is important for the global hydrological cycle.Based on the Coupled Model Intercomparison Project Phase 6(CMIP6)historical experiments and the Global Monsoons Model...The climate variability in global land precipitation is important for the global hydrological cycle.Based on the Coupled Model Intercomparison Project Phase 6(CMIP6)historical experiments and the Global Monsoons Model Intercomparison Project(GMMIP)Tier-1 experiments,the spatialtemporal characteristics of global and regional land precipitation long-term climate changes in CAS FGOALS-f3-L are evaluated in this study.By comparing these two kinds of experiments,the precipitation biases related to the SSTs are also discussed.The results show that the two experiments could capture the precipitation trend and amplitude to a certain degree compared with observations.The GMMIP simulations show a higher skill than the historical runs verified by correlation coefficients partly because the observed monthly mean SST was prescribed.For the Northern Hemisphere,GMMIP can reproduce the trend and variability in global precipitation,while historical simulations cannot reproduce the trend and variability.However,both experiments fail to simulate the amplitude of the southern hemisphere summer precipitation anomalies.Ensemble empirical mode decomposition(EEMD)was applied to compare the simulated precipitation on different time scales.The sea surface temperature anomaly(SSTA)bias,especially the La Ni?a-type SSTA,is the dominant source of the model bias for simulating interannual precipitation anomalies.The authors also emphasize that the response of precipitation anomalies to the ENSO effect varies regionally.This study highlights the importance of the multiannual variability in SSTAs in global and hemispheric precipitation simulations.The ways to improve the simulation of global precipitation for CAS FGOALS-f3-L are also discussed.展开更多
Recent work has shown the dominance of the Himalaya in supporting the Indian summer monsoon （ISM）, perhaps by surface sensible heating along its southern slope and by mechanical blocking acting to separate moist tro...Recent work has shown the dominance of the Himalaya in supporting the Indian summer monsoon （ISM）, perhaps by surface sensible heating along its southern slope and by mechanical blocking acting to separate moist tropical flow from drier midlatitnde air. Previous studies have also shown that Indian snmmer rainfall is largely unaffected in sensitivity experiments that remove only the Tibetan Plateau. However, given the large biases in simulating the monsoon in CMIP5 models, such results may be model dependent. This study investigates the impact of orographic forcing from the Tibetan Plateau, Himalaya and Iranian Plateau on the ISM and East Asian snmmer monsoon （EASM） in the UK Met Office＇s HadGEM3-GA6 and China＇s Institute of Atmospheric Physics FGOALS-FAMIL global climate models. The models chosen featnre oppositesigned biases in their simulation of the ISM rainfall and circulation climatology. The changes to ISM and EASM circulation across the sensitivity experiments are similar in both models and consistent with previous studies. However, considerable differences exist in the rainfall responses over India and China, and in the detailed aspects such as onset and retreat dates. In particular, the models show opposing changes in Indian monsoon rainfall when the Himalaya and Tibetan Plateau orography are removed. Our results show that a multi-model approach, as suggested in the forthcoming Global Monsoon Model Intercomparison Project （GMMIP） associated with CMIP6, is needed to clarify the impact of orographic forcing on the Asian monsoon and to fully understand the implications of model systematic error.展开更多
Three tiers of experiments in the Global Monsoons Model Intercomparison Project(GMMIP),one of the endorsed model intercomparison projects of phase 6 of the Coupled Model Intercomparison Project(CMIP6),are implemented ...Three tiers of experiments in the Global Monsoons Model Intercomparison Project(GMMIP),one of the endorsed model intercomparison projects of phase 6 of the Coupled Model Intercomparison Project(CMIP6),are implemented by the First Institute of Oceanography Earth System Model version 2(FIO-ESM v2.0),following the GMMIP protocols.Evaluation of global mean surface air temperature from 1870 to 2014 and climatological precipitation(1979–2014)in tier-1 shows that the atmosphere model of FIO-ESM v2.0 can reproduce the basic observed atmospheric features.In tier-2,the internal variability is captured by the coupled model,with the SST restoring to the model climatology plus the observed anomalies in the tropical Pacific and North Atlantic.Simulation of the Northern Hemisphere summer monsoon circulation is significantly improved by the SST restoration in the North Atlantic.In tier-3,five orographic perturbation experiments are conducted covering the period 1979–2014 by modifying the surface elevation or vertical heating in the prescribed region.In particular,the strength of the South Asian summer monsoon is reduced by removing the topography or thermal forcing above 500 m over the Asian continent.Monthly and daily simulated outputs of FIO-ESM v2.0 are provided through the Earth System Grid Federation(ESGF)node to contribute to a better understanding of the global monsoon system.展开更多
基金funded by the National Natural Science Foundation of China (Grant Nos. 91737306, 91637312, 41730963, 91837101, 91637208, 41530426)the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (Grant QYZDY-SSW-DQC018)
文摘The Chinese Academy of Sciences(CAS)Flexible Global Ocean Atmosphere Land System(FGOALS-f3-L)model datasets prepared for the sixth phase of the Coupled Model Intercomparison Project(CMIP6)Global Monsoons Model Intercomparison Project(GMMIP)Tier-1 and Tier-3 experiments are introduced in this paper,and the model descriptions,experimental design and model outputs are demonstrated.There are three simulations in Tier-1,with different initial states,and five simulations in Tier-3,with different topographies or surface thermal status.Specifically,Tier-3 contains four orographic perturbation experiments that remove the Tibetan Iranian Plateau,East African and Arabian Peninsula highlands,Sierra Madre,and Andes,and one thermal perturbation experiment that removes the surface sensible heating over the Tibetan Iranian Plateau and surrounding regions at altitudes above 500 m.These datasets will contribute to CMIP6’s value as a benchmark to evaluate the importance of long-term and short-term trends of the sea surface temperature in monsoon circulations and precipitation,and to a better understanding of the orographic impact on the global monsoon system over highlands.
基金jointly funded by the National Key Research and Development Program of ChinaGrant No. 2017YFA0604004the National Natural Science Foundation of China Grant Nos. 91737306,41530426,91837101,91937302,and 41606032。
文摘The climate variability in global land precipitation is important for the global hydrological cycle.Based on the Coupled Model Intercomparison Project Phase 6(CMIP6)historical experiments and the Global Monsoons Model Intercomparison Project(GMMIP)Tier-1 experiments,the spatialtemporal characteristics of global and regional land precipitation long-term climate changes in CAS FGOALS-f3-L are evaluated in this study.By comparing these two kinds of experiments,the precipitation biases related to the SSTs are also discussed.The results show that the two experiments could capture the precipitation trend and amplitude to a certain degree compared with observations.The GMMIP simulations show a higher skill than the historical runs verified by correlation coefficients partly because the observed monthly mean SST was prescribed.For the Northern Hemisphere,GMMIP can reproduce the trend and variability in global precipitation,while historical simulations cannot reproduce the trend and variability.However,both experiments fail to simulate the amplitude of the southern hemisphere summer precipitation anomalies.Ensemble empirical mode decomposition(EEMD)was applied to compare the simulated precipitation on different time scales.The sea surface temperature anomaly(SSTA)bias,especially the La Ni?a-type SSTA,is the dominant source of the model bias for simulating interannual precipitation anomalies.The authors also emphasize that the response of precipitation anomalies to the ENSO effect varies regionally.This study highlights the importance of the multiannual variability in SSTAs in global and hemispheric precipitation simulations.The ways to improve the simulation of global precipitation for CAS FGOALS-f3-L are also discussed.
基金supported jointly by the UK-China Research and Innovation Partnership Fund through the Met Office Climate Science for Service Partnership(CSSP) Chinathe Major Research Plan of the National Natural Science Foundation of China(Grant Nos.91637312 and 91437219)
文摘Recent work has shown the dominance of the Himalaya in supporting the Indian summer monsoon （ISM）, perhaps by surface sensible heating along its southern slope and by mechanical blocking acting to separate moist tropical flow from drier midlatitnde air. Previous studies have also shown that Indian snmmer rainfall is largely unaffected in sensitivity experiments that remove only the Tibetan Plateau. However, given the large biases in simulating the monsoon in CMIP5 models, such results may be model dependent. This study investigates the impact of orographic forcing from the Tibetan Plateau, Himalaya and Iranian Plateau on the ISM and East Asian snmmer monsoon （EASM） in the UK Met Office＇s HadGEM3-GA6 and China＇s Institute of Atmospheric Physics FGOALS-FAMIL global climate models. The models chosen featnre oppositesigned biases in their simulation of the ISM rainfall and circulation climatology. The changes to ISM and EASM circulation across the sensitivity experiments are similar in both models and consistent with previous studies. However, considerable differences exist in the rainfall responses over India and China, and in the detailed aspects such as onset and retreat dates. In particular, the models show opposing changes in Indian monsoon rainfall when the Himalaya and Tibetan Plateau orography are removed. Our results show that a multi-model approach, as suggested in the forthcoming Global Monsoon Model Intercomparison Project （GMMIP） associated with CMIP6, is needed to clarify the impact of orographic forcing on the Asian monsoon and to fully understand the implications of model systematic error.
基金This research was jointly supported by the National Key Research and Development Program of China(Grant No.2017YFC1404004)the Project of Indo-Pacific Ocean Environment Variation and Air-sea Interactions(Grant No.GASIIPOVAI-06)+5 种基金the Basic Scientific Fund of the National Public Research Institute of China(Grant No.2019S06)Ying BAO was supported by the National Key Research and Development Program of China(Grant No.2016YFA0602200)Zhenya SONG was supported by the National Natural Science Foundation of China(Grant No.41821004)the Basic Scientific Fund of the National Public Research Institute of China(Grant No.2016S03)the China–Korea Cooperation Project on Northwestern Pacific Climate Change and its PredictionAll numerical experiments were carried out at the Beijing Super Cloud Computing Center(BSCC).
文摘Three tiers of experiments in the Global Monsoons Model Intercomparison Project(GMMIP),one of the endorsed model intercomparison projects of phase 6 of the Coupled Model Intercomparison Project(CMIP6),are implemented by the First Institute of Oceanography Earth System Model version 2(FIO-ESM v2.0),following the GMMIP protocols.Evaluation of global mean surface air temperature from 1870 to 2014 and climatological precipitation(1979–2014)in tier-1 shows that the atmosphere model of FIO-ESM v2.0 can reproduce the basic observed atmospheric features.In tier-2,the internal variability is captured by the coupled model,with the SST restoring to the model climatology plus the observed anomalies in the tropical Pacific and North Atlantic.Simulation of the Northern Hemisphere summer monsoon circulation is significantly improved by the SST restoration in the North Atlantic.In tier-3,five orographic perturbation experiments are conducted covering the period 1979–2014 by modifying the surface elevation or vertical heating in the prescribed region.In particular,the strength of the South Asian summer monsoon is reduced by removing the topography or thermal forcing above 500 m over the Asian continent.Monthly and daily simulated outputs of FIO-ESM v2.0 are provided through the Earth System Grid Federation(ESGF)node to contribute to a better understanding of the global monsoon system.
