Projected climate change in the South Asia and northern Indian Ocean by the end of the 21st century as obtained from a Regional Earth System Model

Detailed atmospheric, ocean physical and biogeochemical characteristics for the period 2015-2100 within the South Asia CORDEX domain have been obtained from simulations of the Regional Earth System Model ROM.Comparative analysis of average climatic characteristics for the past (1975-2004) and future (2070-2099) climates has been carried out. It shows significant future SST increase, reaching 3&#186;C on average, over the considered area. The salinity of the ocean's upper layer will decrease by 1 &#8240; on average, which indicates a change in the precipitation-evaporation balance in the future climate. The simulated annual MLD will decrease by 5 m in the future. However, this MLD change will be strongly irregular, both in time and space. Simulations also show a widespread decrease of the chlorophyll-a concentration in the surface layer (up to 2 mg Chl m-3) in the future, especially pronounced in the northern and western parts of the Arabian Sea. It is a significant change, given that absolute chlorophyll-a concentration in these areas is typically 3-4 mg Chl m-3 in spring and 5-8 mg Chl m-3 in summer, as obtained for the 1975-2004 model run. The model also shows that the chlorophyll-a concentration at the surface will decrease by 1&#8211;2 mg Chl m-3 along the western coast of the Bay of Bengal in the future. The relative decrease in the surface chlorophyll-a concentration will be about 40% in the future climate in the Arabian Sea and the Bay of Bengal.The model solution according to the SSP5-8.5 scenario shows a decrease in the amount of precipitation in the future climate (up to 3-4 mm/day) over the northeastern part of India and over Nepal in summer. But over the central part of India, in the Andaman Sea, over Thailand and Myanmar, there will be an increase in the amount of precipitation. The total continental runoff into the Bay of Bengal will increase, but the runoff in the Ganges delta will be greatly weakened. Thus, despite the decrease in the runoff of the Ganges and Brahmaputra rivers, the total continental runoff into the Bay of Bengal turns out to be higher in the future climate (2070-2099) relative to retrospective calculations (1975-2004) due to the runoff of smaller rivers.&#160;Acknowledgements: This work is funded by Russian Science Foundation (RSF, Project 19-47-02015) and Department of Science and Technology (DST, Govt. of India, grant DST/INT/RUS/RSF/P-33/G). The research was performed in the framework of the state assignment of the Ministry of Science and Higher Education of Russia (theme No. 0128-2021-0014). This work used resources of the Deutsches Klimarechenzentrum (DKRZ) granted by its Scientific Steering Committee (WLA) under project ID ba1144.

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Evolution of the Arabian Sea Upwelling from the Last Millennium to the Future as Simulated by Earth System Models

Climate ◽

10.3390/cli9050072 ◽

2021 ◽

Vol 9 (5) ◽

pp. 72

Author(s):

Xing Yi ◽

Birgit Hünicke ◽

Eduardo Zorita

Keyword(s):

Arabian Sea ◽

Positive Trend ◽

Last Millennium ◽

Earth System ◽

System Models ◽

Sediment Records ◽

The Future ◽

Water Stratification ◽

Arabian Sea Upwelling ◽

Earth System Models

Arabian Sea upwelling in the past has been generally studied based on the sediment records. We apply two earth system models and analyze the simulated water vertical velocity to investigate coastal upwelling in the western Arabian Sea over the last millennium. In addition, two models with slightly different configurations are also employed to study the upwelling in the 21st century under the strongest and the weakest greenhouse gas emission scenarios. With a negative long-term trend caused by the orbital forcing of the models, the upwelling over the last millennium is found to be closely correlated with the sea surface temperature, the Indian summer Monsoon and the sediment records. The future upwelling under the Representative Concentration Pathway (RCP) 8.5 scenario reveals a negative trend, in contrast with the positive trend displayed by the upwelling favorable along-shore winds. Therefore, it is likely that other factors, like water stratification in the upper ocean layers caused by the stronger surface warming, overrides the effect from the upwelling favorable wind. No significant trend is found for the upwelling under the RCP2.6 scenario, which is likely due to a compensation between the opposing effects of the increase in upwelling favorable winds and the water stratification.

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Comparison of summer chlorophyll a concentration in the South China Sea and the Arabian Sea using remote sensing data

Acta Oceanologica Sinica ◽

10.1007/s13131-017-1138-4 ◽

2017 ◽

Vol 36 (11) ◽

pp. 61-67

Author(s):

Jinglong Yao ◽

Lei Yang ◽

Yeqiang Shu ◽

Lili Zeng ◽

Rui Shi ◽

...

Keyword(s):

Remote Sensing ◽

South China Sea ◽

Chlorophyll A ◽

South China ◽

Arabian Sea ◽

Remote Sensing Data ◽

The South China Sea ◽

Chlorophyll A Concentration ◽

Sensing Data ◽

China Sea

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Aerosols and their impacts on future Arctic climate change under different emission projections in the GISS-E2.1 Earth system model

10.5194/egusphere-egu21-2566 ◽

2021 ◽

Author(s):

Ulas Im ◽

Kostas Tsigaridis ◽

Gregory S. Faluvegi ◽

Peter L. Langen ◽

Joshua P. French ◽

...

Keyword(s):

Sea Ice ◽

Earth System Model ◽

System Model ◽

The Arctic ◽

Earth System ◽

Anthropogenic Aerosols ◽

Emission Reductions ◽

Air Temperatures ◽

The Future ◽

Emission Projections

In order to study the future aerosol burdens and their radiative and climate impacts over the Arctic (>60 &#176;N), future (2015-2050) simulations have been carried out using the GISS-E2.1 Earth system model. Different future anthrpogenic emission projections have been used from the Eclipse V6b and the Coupled Model Intercomparison Project Phase 6 (CMIP6) databases. Results showed that&#160;Arctic BC, OC and SO42- burdens decrease significantly in all simulations following the emission projections, with the CMIP6 ensemble showing larger reductions in Arctic aerosol burdens compared to the Eclipse ensemble. For the 2030-2050 period, both the Eclipse Current Legislation (CLE) and the Maximum Feasible Reduction (MFR) ensembles simulated an aerosol top of the atmosphere (TOA) forcing of -0.39&#177;0.01 W m-2, of which -0.24&#177;0.01 W m-2 were attributed to the anthropogenic aerosols. The CMIP6 SSP3-7.0 scenario simulated a TOA aerosol forcing of -0.35 W m-2 for the same period, while SSP1-2.6 and SSP2-4.5 scenarios simulated a slightly more negative TOA forcing (-0.40 W m-2), of which the anthropogenic aerosols accounted for -0.26 W m-2. The 2030-2050 mean surface air temperatures are projected to increase by 2.1 &#176;C and 2.4 &#176;C compared to the 1990-2010 mean temperature according to the Eclipse CLE and MFR ensembles, respectively, while the CMIP6 simulation calculated an increase of 1.9 &#176;C (SSP1-2.6) to 2.2 &#176;C (SSP3-7.0). Overall, results show that even the scenarios with largest emission reductions lead to similar impact on the future Arctic surface air temperatures compared to scenarios with smaller emission reductions, while scenarios with no or little mitigation leads to much larger sea-ice loss, implying that even though the magnitude of aerosol reductions lead to similar responses in surface air temperatures, high mitigation of aerosols are still necessary to limit sea-ice loss.&#160;

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Setup of the PMIP3 paleoclimate experiments conducted using an Earth System Model, MIROC-ESM

Geoscientific Model Development Discussions ◽

10.5194/gmdd-5-2527-2012 ◽

2012 ◽

Vol 5 (3) ◽

pp. 2527-2569 ◽

Cited By ~ 1

Author(s):

T. Sueyoshi ◽

R. Ohgaito ◽

A. Yamamoto ◽

M. O. Chikamoto ◽

T. Hajima ◽

...

Keyword(s):

Climate Model ◽

Coupled Model ◽

Earth System Model ◽

Future Climate ◽

System Model ◽

Climate Feedback ◽

Climate Projections ◽

Earth System ◽

Intergovernmental Panel ◽

Intercomparison Project

Abstract. The importance of climate model evaluation using paleoclimate simulations for better future climate projections has been recognized by the Intergovernmental Panel on Climate Change. In recent years, Earth System Models (ESMs) were developed to investigate carbon-cycle climate feedback, as well as to project the future climate. Paleoclimate events, especially those associated with the variations in atmospheric CO2 level or land vegetation, provide suitable benchmarks to evaluate ESMs. Here we present implementations of the paleoclimate experiments proposed by the Coupled Model Intercomparison Project phase 5/Paleoclimate Modelling Intercomparison Project phase 3 (CMIP5/PMIP3) using an Earth System Model, MIROC-ESM. In this paper, experimental settings and procedures of the mid-Holocene, the Last Glacial Maximum, and the Last Millennium experiments are explained. The first two experiments are time slice experiments and the last one is a transient experiment. The complexity of the model requires various steps to correctly configure the experiments. Several basic outputs are also shown.

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