The Pliocene Model Intercomparison Project Phase 2: large-scale climate features and climate sensitivity

Climate of the past, Journal Year: 2020, Volume and Issue: 16(6), P. 2095 - 2123

Published: Nov. 4, 2020

Abstract. The Pliocene epoch has great potential to improve our understanding of the long-term climatic and environmental consequences an atmospheric CO2 concentration near ∼400 parts per million by volume. Here we present large-scale features climate as simulated a new ensemble models varying complexity spatial resolution based on reconstructions boundary conditions (the Model Intercomparison Project Phase 2; PlioMIP2). As global annual average, modelled surface air temperatures increase between 1.7 5.2 ∘C relative pre-industrial era with multi-model mean value 3.2 ∘C. Annual total precipitation rates 7 % (range: 2 %–13 %). On temperature (SAT) increases 4.3 over land 2.8 oceans. There is clear pattern polar amplification warming polewards 60∘ N S exceeding factor 2.3. In Atlantic Pacific oceans, meridional gradients are reduced, while tropical zonal remain largely unchanged. statistically significant relationship model's response associated doubling in (equilibrium sensitivity; ECS) its response. Earth system (including ice sheet feedbacks) 67 greater than ECS; this larger 47 obtained from PlioMIP1 ensemble. Proxy-derived estimates sea used assess model ECS give range 2.6–4.8 This result general accord presented previous Intergovernmental Panel Climate Change (IPCC) Assessment Reports.

Language: Английский

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A comprehensive evaluation of soil moisture and soil temperature from third‐generation atmospheric and land reanalysis data sets

International Journal of Climatology, Journal Year: 2020, Volume and Issue: 40(13), P. 5744 - 5766

Published: March 14, 2020

Abstract Soil moisture and soil temperature, reflecting a synthetic climate regime, are vitally important for change assessments adaption. As historical in situ measurements of states extremely scarce spatially uneven, reanalysis products play an increasingly role filling these gaps. The focus this paper is on water–heat covariations joint evaluation temperature five widely used atmospheric land reanalyses presented using observations from 25 networks during various periods 1979 to 2017. At the network scale, show statistically significant correlations with observations, European Centre Medium‐Range Weather Forecasts ERA5 shows higher skills than other four improvement over its predecessor. National Centers Environmental Prediction Climate Forecast System Reanalysis performs better terms long‐term trends. most skilful signals seasonal cycles, correlation coefficients 0.9. However, trends substantially weaker observed still tend perform poorly high latitudes cold seasons. even skills, mean 0.9 between anomalies; enhanced annual ranges toward altitudes. A showed physically consistent conjunction fluxes growing season Northern Hemisphere. This report suggests good future their potential surface assessments.

Language: Английский

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Is there warming in the pipeline? A multi-model analysis of the Zero Emissions Commitment from CO<sub>2</sub>

Biogeosciences, Journal Year: 2020, Volume and Issue: 17(11), P. 2987 - 3016

Published: June 15, 2020

Abstract. The Zero Emissions Commitment (ZEC) is the change in global mean temperature expected to occur following cessation of net CO2 emissions and as such a critical parameter for calculating remaining carbon budget. Model Intercomparison Project (ZECMIP) was established gain better understanding potential magnitude sign ZEC, addition processes that underlie this metric. A total 18 Earth system models both full intermediate complexity participated ZECMIP. All conducted an experiment where atmospheric concentration increases exponentially until 1000 PgC has been emitted. Thereafter are set zero configured allow free evolution concentration. Many additional second-priority simulations with different cumulative emission totals alternative idealized pathway gradual transition emissions. inter-model range ZEC 50 years after cease −0.36 0.29 ∘C, model ensemble −0.07 median −0.05 standard deviation 0.19 ∘C. Models exhibit wide variety behaviours cease, some continuing warm decades millennia others cooling substantially. Analysis shows uptake by ocean terrestrial biosphere important counteracting warming effect from reduction heat cease. This difficult constrain due high uncertainty efficacy uptake. Overall, most likely value on multi-decadal timescales close zero, consistent previous experiments simple theory.

Language: Английский

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Global land use for 2015–2100 at 0.05° resolution under diverse socioeconomic and climate scenarios

Scientific Data, Journal Year: 2020, Volume and Issue: 7(1)

Published: Oct. 2, 2020

Abstract Global future land use (LU) is an important input for Earth system models projecting dynamics and critical many modeling studies on global change. Here we generated a new gridded LU dataset using the Change Analysis Model (GCAM) spatial downscaling model, named Demeter, under five Shared Socioeconomic Pathways (SSPs) four Representative Concentration (RCPs) scenarios. Compared to existing similar datasets, presented has higher resolution (0.05° × 0.05°) spreads more comprehensive set of SSP-RCP scenarios (in total 15 scenarios), considers uncertainties from forcing climates. We compared our with Land Use Harmonization version 2 (LUH2) found results are in general spatially consistent LUH2. The will be useful studies, especially analysis impacts cover change socioeconomics, as well characterizing associated these impacts.

Language: Английский

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Eco‐evolutionary optimality as a means to improve vegetation and land‐surface models

New Phytologist, Journal Year: 2021, Volume and Issue: 231(6), P. 2125 - 2141

Published: June 16, 2021

Summary Global vegetation and land‐surface models embody interdisciplinary scientific understanding of the behaviour plants ecosystems, are indispensable to project impacts environmental change on interactions between climate. However, systematic errors persistently large differences among carbon water cycle projections by different highlight limitations current process formulations. In this review, focusing core plant functions in terrestrial cycles, we show how unifying hypotheses derived from eco‐evolutionary optimality (EEO) principles can provide novel, parameter‐sparse representations processes. We present case studies that demonstrate EEO generates parsimonious core, leaf‐level processes individually testable supported evidence. approaches photosynthesis primary production, dark respiration stomatal ripe for implementation global models. other important traits, including leaf economics spectrum applications at community level active research areas. Independently tested modules emerging could profitably be integrated into modelling frameworks account multiple time scales which communities adjust change.

Language: Английский

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