CAS-FGOALS Datasets for the Two Interglacial Epochs of the Holocene and the Last Interglacial in PMIP4

Abstract Two versions of the Chinese Academy of Sciences Flexible Global Ocean-Atmosphere-Land System model (CAS-FGOALS), version f3-L and g3, are used to simulate the two interglacial epochs of the mid-Holocene and the Last Interglacial in phase 4 of the Paleoclimate Modelling Intercomparison Project (PMIP4), which aims to study the impact of changes in orbital parameters on the Earth’s climate. Following the PMIP4 experimental protocols, four simulations for the mid-Holocene and two simulations for the Last Interglacial have been completed, and all the data, including monthly and daily outputs for the atmospheric, oceanic, land and sea-ice components, have been released on the Earth System Grid Federation (ESGF) node. These datasets contribute to PMIP4 and CMIP6 (phase 6 of the Coupled Model Intercomparison Project) by providing the variables necessary for the two interglacial periods. In this paper, the basic information of the CAS-FGOALS models and the protocols for the two interglacials are briefly described, and the datasets are validated using proxy records. Results suggest that the CAS-FGOALS models capture the large-scale changes in the climate system in response to changes in solar insolation during the interglacial epochs, including warming in mid-to-high latitudes, changes in the hydrological cycle, the seasonal variation in the extent of sea ice, and the damping of interannual variabilities in the tropical Pacific. Meanwhile, disagreements within and between the models and the proxy data are also presented. These datasets will help the modeling and the proxy data communities with a better understanding of model performance and biases in paleoclimate simulations.

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Experimental and diagnostic protocol for the physical component of the CMIP6 Ocean Model Intercomparison Project (OMIP)

10.5194/gmd-2016-77 ◽

2016 ◽

Cited By ~ 4

Author(s):

Stephen M. Griffies ◽

Gokhan Danabasoglu ◽

Paul J. Durack ◽

Alistair J. Adcroft ◽

V. Balaji ◽

...

Keyword(s):

Sea Ice ◽

Global Climate ◽

Coupled Model ◽

Companion Paper ◽

Ocean Model ◽

Global Ocean ◽

Model Intercomparison ◽

Experimental Protocol ◽

Diagnostic Protocol ◽

Intercomparison Project

Abstract. The Ocean Model Intercomparison Project (OMIP) aims to provide a framework for evaluating, understanding, and improving the ocean and sea-ice components of global climate and earth system models contributing to the Coupled Model Intercomparison Project Phase 6 (CMIP6). OMIP addresses these aims in two complementary manners: (A) by providing an experimental protocol for global ocean/sea-ice models run with a prescribed atmospheric forcing, (B) by providing a protocol for ocean diagnostics to be saved as part of CMIP6. We focus here on the physical component of OMIP, with a companion paper (Orr et al., 2016) offering details for the inert chemistry and interactive biogeochemistry. The physical portion of the OMIP experimental protocol follows that of the interannual Coordinated Ocean-ice Reference Experiments (CORE-II). Since 2009, CORE-I (Normal Year Forcing) and CORE-II have become the standard method to evaluate global ocean/sea-ice simulations and to examine mechanisms for forced ocean climate variability. The OMIP diagnostic protocol is relevant for any ocean model component of CMIP6, including the DECK (Diagnostic, Evaluation and Characterization of Klima experiments), historical simulations, FAFMIP (Flux Anomaly Forced MIP), C4MIP (Coupled Carbon Cycle Climate MIP), DAMIP (Detection and Attribution MIP), DCPP (Decadal Climate Prediction Project), ScenarioMIP (Scenario MIP), as well as the ocean-sea ice OMIP simulations. The bulk of this paper offers scientific rationale for saving these diagnostics.

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The last interglacial (Eemian) climate simulated by LOVECLIM and CCSM3

Climate of the Past Discussions ◽

10.5194/cpd-8-5293-2012 ◽

2012 ◽

Vol 8 (5) ◽

pp. 5293-5340 ◽

Cited By ~ 2

Author(s):

I. Nikolova ◽

Q. Yin ◽

A. Berger ◽

U. K. Singh ◽

M. P. Karami

Keyword(s):

Large Scale ◽

Climate Models ◽

Hydrological Cycle ◽

The Arctic ◽

Boreal Summer ◽

Interglacial Period ◽

Last Interglacial ◽

Proxy Data ◽

Vegetation Feedback ◽

Depth Analysis

Abstract. This paper presents a detailed analysis of the climate of the last interglacial simulated by two climate models of different complexities, LOVECLIM and CCSM3. The simulated surface temperature, hydrological cycle, vegetation and ENSO variability during the last interglacial are analyzed through the comparison with the simulated Pre-Industrial (PI) climate. In both models, the last interglacial period is characterized by a significant warming (cooling) over almost all the continents during boreal summer (winter) leading to a largely increased (reduced) seasonal contrast in the northern (southern) hemisphere. This is mainly due to the much higher (lower) insolation received by the whole Earth in boreal summer (winter) during this interglacial. The arctic is warmer than PI through the whole year, resulting from its much higher summer insolation and its remnant effect in the following fall-winter through the interactions between atmosphere, ocean and sea ice. In the tropical Pacific, the change in the SST annual cycle is suggested to be related to a minor shift towards an El Nino, slightly stronger for MIS-5 than for PI. Intensified African monsoon and vegetation feedback are responsible for the cooling during summer in North Africa and Arabian Peninsula. Over India precipitation maximum is found further west, while in Africa the precipitation maximum migrates further north. Trees and grassland expand north in Sahel/Sahara. A mix of forest and grassland occupies continents and expand deep in the high northern latitudes. Desert areas reduce significantly in Northern Hemisphere, but increase in North Australia. The simulated large-scale climate change during the last interglacial compares reasonably well with proxy data, giving credit to both models and reconstructions. However, discrepancies exist at some regional scales between the two models, indicating the necessity of more in depth analysis of the models and comparisons with proxy data.

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UK Global Ocean GO6 and GO7: a traceable hierarchy of model resolutions

Geoscientific Model Development ◽

10.5194/gmd-11-3187-2018 ◽

2018 ◽

Vol 11 (8) ◽

pp. 3187-3213 ◽

Cited By ~ 44

Author(s):

David Storkey ◽

Adam T. Blaker ◽

Pierre Mathiot ◽

Alex Megann ◽

Yevgeny Aksenov ◽

...

Keyword(s):

Southern Ocean ◽

Sea Ice ◽

Large Scale ◽

Coupled Model ◽

Weddell Sea ◽

Global Ocean ◽

Near Surface ◽

Ice Shelves ◽

Surface Circulation ◽

The Uk

Abstract. Versions 6 and 7 of the UK Global Ocean configuration (known as GO6 and GO7) will form the ocean components of the Met Office GC3.1 coupled model and UKESM1 earth system model to be used in CMIP61 simulations. The label “GO6” refers to a traceable hierarchy of three model configurations at nominal 1, 1∕4 and 1/12∘ resolutions. The GO6 configurations are described in detail with particular focus on aspects which have been updated since the previous version (GO5). Results of 30-year forced ocean-ice integrations with the 1/4∘ model are presented, in which GO6 is coupled to the GSI8.1 sea ice configuration and forced with CORE22 fluxes. GO6-GSI8.1 shows an overall improved simulation compared to GO5-GSI5.0, especially in the Southern Ocean where there are more realistic summertime mixed layer depths, a reduced near-surface warm and saline biases, and an improved simulation of sea ice. The main drivers of the improvements in the Southern Ocean simulation are tuning of the vertical and isopycnal mixing parameters. Selected results from the full hierarchy of three resolutions are shown. Although the same forcing is applied, the three models show large-scale differences in the near-surface circulation and in the short-term adjustment of the overturning circulation. The GO7 configuration is identical to the GO6 1/4∘ configuration except that the cavities under the ice shelves are opened. Opening the ice shelf cavities has a local impact on temperature and salinity biases on the Antarctic shelf with some improvement in the biases in the Weddell Sea.

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Large-scale features and evaluation of the PMIP4-CMIP6 <i>midHolocene</i> simulations

Climate of the Past ◽

10.5194/cp-16-1847-2020 ◽

2020 ◽

Vol 16 (5) ◽

pp. 1847-1872 ◽

Cited By ~ 7

Author(s):

Chris M. Brierley ◽

Anni Zhao ◽

Sandy P. Harrison ◽

Pascale Braconnot ◽

Charles J. R. Williams ◽

...

Keyword(s):

Large Scale ◽

Climate Models ◽

Hydrological Cycle ◽

Global Climate ◽

Coupled Model ◽

Global Climate Models ◽

Current Phase ◽

Model Intercomparison ◽

Global Mean Temperature ◽

Intercomparison Project

Abstract. The mid-Holocene (6000 years ago) is a standard time period for the evaluation of the simulated response of global climate models using palaeoclimate reconstructions. The latest mid-Holocene simulations are a palaeoclimate entry card for the Palaeoclimate Model Intercomparison Project (PMIP4) component of the current phase of the Coupled Model Intercomparison Project (CMIP6) – hereafter referred to as PMIP4-CMIP6. Here we provide an initial analysis and evaluation of the results of the experiment for the mid-Holocene. We show that state-of-the-art models produce climate changes that are broadly consistent with theory and observations, including increased summer warming of the Northern Hemisphere and associated shifts in tropical rainfall. Many features of the PMIP4-CMIP6 simulations were present in the previous generation (PMIP3-CMIP5) of simulations. The PMIP4-CMIP6 ensemble for the mid-Holocene has a global mean temperature change of −0.3 K, which is −0.2 K cooler than the PMIP3-CMIP5 simulations predominantly as a result of the prescription of realistic greenhouse gas concentrations in PMIP4-CMIP6. Biases in the magnitude and the sign of regional responses identified in PMIP3-CMIP5, such as the amplification of the northern African monsoon, precipitation changes over Europe, and simulated aridity in mid-Eurasia, are still present in the PMIP4-CMIP6 simulations. Despite these issues, PMIP4-CMIP6 and the mid-Holocene provide an opportunity both for quantitative evaluation and derivation of emergent constraints on the hydrological cycle, feedback strength, and potentially climate sensitivity.

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OMIP contribution to CMIP6: experimental and diagnostic protocol for the physical component of the Ocean Model Intercomparison Project

Geoscientific Model Development ◽

10.5194/gmd-9-3231-2016 ◽

2016 ◽

Vol 9 (9) ◽

pp. 3231-3296 ◽

Cited By ~ 78

Author(s):

Stephen M. Griffies ◽

Gokhan Danabasoglu ◽

Paul J. Durack ◽

Alistair J. Adcroft ◽

V. Balaji ◽

...

Keyword(s):

Sea Ice ◽

Coupled Model ◽

Climate Science ◽

Companion Paper ◽

Ocean Model ◽

Global Ocean ◽

Model Intercomparison ◽

Experimental Protocol ◽

Diagnostic Protocol ◽

Intercomparison Project

Abstract. The Ocean Model Intercomparison Project (OMIP) is an endorsed project in the Coupled Model Intercomparison Project Phase 6 (CMIP6). OMIP addresses CMIP6 science questions, investigating the origins and consequences of systematic model biases. It does so by providing a framework for evaluating (including assessment of systematic biases), understanding, and improving ocean, sea-ice, tracer, and biogeochemical components of climate and earth system models contributing to CMIP6. Among the WCRP Grand Challenges in climate science (GCs), OMIP primarily contributes to the regional sea level change and near-term (climate/decadal) prediction GCs.OMIP provides (a) an experimental protocol for global ocean/sea-ice models run with a prescribed atmospheric forcing; and (b) a protocol for ocean diagnostics to be saved as part of CMIP6. We focus here on the physical component of OMIP, with a companion paper (Orr et al., 2016) detailing methods for the inert chemistry and interactive biogeochemistry. The physical portion of the OMIP experimental protocol follows the interannual Coordinated Ocean-ice Reference Experiments (CORE-II). Since 2009, CORE-I (Normal Year Forcing) and CORE-II (Interannual Forcing) have become the standard methods to evaluate global ocean/sea-ice simulations and to examine mechanisms for forced ocean climate variability. The OMIP diagnostic protocol is relevant for any ocean model component of CMIP6, including the DECK (Diagnostic, Evaluation and Characterization of Klima experiments), historical simulations, FAFMIP (Flux Anomaly Forced MIP), C4MIP (Coupled Carbon Cycle Climate MIP), DAMIP (Detection and Attribution MIP), DCPP (Decadal Climate Prediction Project), ScenarioMIP, HighResMIP (High Resolution MIP), as well as the ocean/sea-ice OMIP simulations.

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UK Global Ocean GO6 and GO7: a traceable hierarchy of model resolutions

10.5194/gmd-2017-263 ◽

2018 ◽

Cited By ~ 5

Author(s):

David Storkey ◽

Adam T. Blaker ◽

Pierre Mathiot ◽

Alex Megann ◽

Yevgeny Aksenov ◽

...

Keyword(s):

Southern Ocean ◽

Sea Ice ◽

Large Scale ◽

Coupled Model ◽

Weddell Sea ◽

Global Ocean ◽

Near Surface ◽

Ice Shelves ◽

Surface Circulation ◽

The Uk

Abstract. Versions 6 and 7 of the UK Global Ocean conﬁguration (known as GO6 and GO7) will form the ocean components of the Met Ofﬁce GC3.1 coupled model and UKESM earth system model to be used in CMIP6 simulations. The label "GO6" refers to a traceable hierarchy of three model conﬁgurations at nominal 1°, 1/4° and 1/12° resolution. The GO6 conﬁgurations are described in detail with particular focus on aspects which have been updated since the previous version (GO5). Results of 30-year forced ocean-ice integrations with the 1/4° model are presented, in which GO6 is coupled to the GSI8.1 sea ice conﬁguration and forced with CORE2 ﬂuxes. GO6-GSI8.1 shows an overall improved simulation compared to GO5-GSI5.0, especially in the Southern Ocean where there are more realistic summertime mixed layer depths, a reduced near-surface warm and saline biases and an improved simulation of sea ice. The main drivers of the improvements in the Southern Ocean simulation are tunings of the vertical and isopycnal mixing parameters. Selected results from the full hierarchy of three resolutions are shown. Although the same forcing is applied, the three models show large-scale differences in the near-surface circulation and in the short-term adjustment of the overturning circulation. The GO7 conﬁguration is identical to the GO6 1/4° conﬁguration except that the cavities under the ice shelves are opened. Opening the ice shelf cavities has a local impact on temperature and salinity biases on the Antarctic shelf with some improvement in the biases in the Weddell Sea.

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Moving beyond the Total Sea Ice Extent in Gauging Model Biases

Journal of Climate ◽

10.1175/jcli-d-16-0026.1 ◽

2016 ◽

Vol 29 (24) ◽

pp. 8965-8987 ◽

Cited By ~ 14

Author(s):

Detelina P. Ivanova ◽

Peter J. Gleckler ◽

Karl E. Taylor ◽

Paul J. Durack ◽

Kate D. Marvel

Keyword(s):

Sea Ice ◽

Error Compensation ◽

Climate Modeling ◽

Model Performance ◽

Coupled Model ◽

Cmip5 Models ◽

Model Errors ◽

Sea Ice Extent ◽

Model Biases ◽

The Impact

Abstract Reproducing characteristics of observed sea ice extent remains an important climate modeling challenge. This study describes several approaches to improve how model biases in total sea ice distribution are quantified, and applies them to historically forced simulations contributed to phase 5 of the Coupled Model Intercomparison Project (CMIP5). The quantity of hemispheric total sea ice area, or some measure of its equatorward extent, is often used to evaluate model performance. A new approach is introduced that investigates additional details about the structure of model errors, with an aim to reduce the potential impact of compensating errors when gauging differences between simulated and observed sea ice. Using multiple observational datasets, several new methods are applied to evaluate the climatological spatial distribution and the annual cycle of sea ice cover in 41 CMIP5 models. It is shown that in some models, error compensation can be substantial, for example resulting from too much sea ice in one region and too little in another. Error compensation tends to be larger in models that agree more closely with the observed total sea ice area, which may result from model tuning. The results herein suggest that consideration of only the total hemispheric sea ice area or extent can be misleading when quantitatively comparing how well models agree with observations. Further work is needed to fully develop robust methods to holistically evaluate the ability of models to capture the finescale structure of sea ice characteristics; however, the “sector scale” metric used here aids in reducing the impact of compensating errors in hemispheric integrals.

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Impact of Large-Scale Ocean–Atmosphere Interactions on Interannual Water Storage Changes in the Tropics and Subtropics

Remote Sensing ◽

10.3390/rs13173529 ◽

2021 ◽

Vol 13 (17) ◽

pp. 3529

Author(s):

Shengnan Ni ◽

Zhicai Luo ◽

Jianli Chen ◽

Jin Li

Keyword(s):

Large Scale ◽

Hydrological Cycle ◽

Southern Oscillation ◽

Water Storage ◽

Least Square ◽

Global Ocean ◽

Climate Indices ◽

Ocean Atmosphere ◽

The Tropics ◽

The Impact

Satellite observations from the Gravity Recovery and Climate Experiment (GRACE) provide unique measurements of global terrestrial water storage (TWS) changes at different spatial and temporal scales. Large-scale ocean–atmosphere interactions might have significant impacts on the global hydrological cycle, resulting in considerable influences on TWS changes. Quantifying the contributions of large-scale ocean–atmosphere interactions to TWS changes would be beneficial to improving our understanding of water storage responses to climate variability. In the study, we investigate the impact of three major global ocean–atmosphere interactions—El Niño and Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), and Atlantic Meridional Mode (AMM) on interannual TWS changes in the tropics and subtropics, using GRACE measurements and climate indices. Based on the least square principle, these climate indices, and the corresponding Hilbert transformations along with a linear trend, annual and semi-annual terms are fitted to the TWS time series on global 1° × 1° grids. By the fitted results, we analyze the connections between interannual TWS changes and ENSO, IOD, and AMM indices, and estimate the quantitative contributions of these climate phenomena to TWS changes. The results indicate that interannual TWS changes in the tropics and subtropics are related to ENSO, IOD, and AMM climate phenomena. The contribution of each climate phenomenon to TWS changes might vary in different regions, but in most parts of the tropics and subtropics, the ENSO contribution to TWS changes is found to be more dominant than those from IOD and AMM.

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Two Interglacials: Scientific Objectives and Experimental Designs for CMIP6 and PMIP4 Holocene and Last Interglacial Simulations

10.5194/cp-2016-106 ◽

2016 ◽

Cited By ~ 1

Author(s):

Bette L. Otto-Bliesner ◽

Pascale Braconnot ◽

Sandy P. Harrison ◽

Daniel J. Lunt ◽

Ayako Abe-Ouchi ◽

...

Keyword(s):

Land Surface ◽

Radiative Forcing ◽

Large Scale ◽

Climate Changes ◽

Systematic Evaluation ◽

Before Present ◽

Last Interglacial ◽

Sensitivity Experiments ◽

Intercomparison Project ◽

The Impact

Abstract. Two interglacial epochs are included in the suite of paleoclimate simulations in the present phase of the Coupled Model Intercomparison Project (CMIP6). Equilibrium simulations of the mid-Holocene (midHolocene, 6000 years before present) and the Last Interglacial (lig127k, 127,000 years before present) are designed to examine the impact of changes in orbital forcing at times when atmospheric greenhouse gas levels were similar to those of the preindustrial period and the continental configurations were almost identical to modern. These simulations test our understanding of the interplay between radiative forcing and atmospheric circulation, and the connections among large-scale and regional climate changes giving rise to phenomena such as land-sea contrast and high-latitude amplification in temperature changes, and responses of the monsoons, as compared to today. They also provide an opportunity, through carefully designed additional sensitivity experiments as part of the Paleoclimate Modeling Intercomparison Project (PMIP4), to quantify the strength of atmosphere, ocean, cryosphere, and land-surface feedbacks. Sensitivity experiments are proposed to investigate the role of freshwater forcing in triggering abrupt climate changes within interglacial epochs. These feedback experiments naturally lead to a focus on climate evolution during interglacial periods, which will be examined through transient experiments. Analyses of the sensitivity simulations will also focus on interactions between extratropical and tropical circulation, and the relationship between changes in mean climate state and climate variability on annual to multi-decadal timescales. The comparative abundance of paleoenvironmental data and of quantitative climate reconstructions for the Holocene and Last Interglacial make these two epochs ideal candidates for systematic evaluation of model performance, and such comparisons will shed new light on the importance of external feedbacks (e.g., vegetation, dust) and the ability of state-of-the-art models to simulate climate changes realistically.

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Simulating the mid-Holocene, Last Interglacial and mid-Pliocene climate with EC-Earth3-LR

10.5194/gmd-2020-208 ◽

2020 ◽

Cited By ~ 2

Author(s):

Qiong Zhang ◽

Qiang Li ◽

Qiang Zhang ◽

Ellen Berntell ◽

Josefine Axelsson ◽

...

Keyword(s):

Large Scale ◽

Climate Changes ◽

Climate Models ◽

Coupled Model ◽

Walker Circulation ◽

Earth Model ◽

Model Intercomparison ◽

Test Bed ◽

Last Interglacial ◽

Intercomparison Project

Abstract. Paleoclimate modelling has long been regarded as a strong out-of-sample test-bed of the climate models that are used for the projection of future climate changes. For the first time, the EC-Earth model contributes to the Paleoclimate Model Intercomparison Project (PMIP) phase 4, which is part of the current sixth phase of the Coupled Model Intercomparison Project (CMIP6). Here, we document the model setup for PMIP4 experiments with EC-Earth3-LR and present the results on the large-scale features from the completed production simulations for the three past warm periods (mid-Holocene, Last Interglacial, and mid-Pliocene). Using the pre-industrial climate as a reference state, we show the changes in global temperature, large scale Hadley circulation and Walker circulation, polar warming and global monsoons, as well as the climate variability modes (ENSO, PDO, AMO). The EC-Earth3-LR simulates reasonable climate responses during past warm periods as shown in the other PMIP4-CMIP6 model ensemble. The systematic comparison of these climate changes in three past warm periods in an individual model demonstrates the ability of the model to capture the climate response under different climate forcings, providing potential implications for confidence in future projections with EC-Earth model.

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