The GFDL Global Atmospheric Chemistry‐Climate Model AM4.1: Model Description and Simulation Characteristics

Journal of Advances in Modeling Earth Systems, Journal Year: 2020, Volume and Issue: 12(10)

Published: Aug. 25, 2020

Abstract We describe the baseline model configuration and simulation characteristics of Geophysical Fluid Dynamics Laboratory (GFDL)'s Atmosphere Model version 4.1 (AM4.1), which builds on developments at GFDL over 2013–2018 for coupled carbon‐chemistry‐climate as part sixth phase Coupled Intercomparison Project. In contrast with GFDL's AM4.0 development effort, focused physical aerosol interactions is used atmospheric component CM4.0, AM4.1 focuses comprehensiveness Earth system interactions. Key features this include doubled horizontal resolution atmosphere (~200 to ~100 km) revised dynamics physics from previous‐generation AM3 chemistry‐climate model. improved representation chemical composition, including precursor emissions, key land‐atmosphere interactions, comprehensive land‐atmosphere‐ocean cycling dust iron, interactive ocean‐atmosphere reactive nitrogen. provides vast improvements in fidelity AM3, captures most AM4.0's simulations characteristics, notably improves aerosols Southern Ocean, India, China—even its chemistry representation—and manifestation sudden stratospheric warmings coldest months. Distributions nitrogen sulfur species, carbon monoxide, ozone are all substantially AM3. Fidelity concerns degradation upper equatorial winds some regions.

Language: Английский

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Historical and Future Projected Warming of Antarctic Shelf Bottom Water in CMIP6 Models

Geophysical Research Letters, Journal Year: 2021, Volume and Issue: 48(10)

Published: April 19, 2021

Abstract Understanding warming on the Antarctic shelf is critical for projecting changes in ice shelves and sheets. Here we assess Shelf Bottom Water (ASBW) temperature mean‐state trends CMIP6 models. While models do not resolve shelves, future water will impact vulnerability. The multi‐model mean zonal structure ASBW spatial pattern resemble observations, although there considerable spread across a warm bias. projects an average of 0.36°C (interdecile range 0.07°C–0.60°C) under SSP245 0.62°C 0.16°C–0.95°C) SSP585 by 2100, emphasizing influence emissions have around Antarctica. Changes transport Circumpolar Deep onto associated with Southern Annular Mode, as well warming, are predicted to conspire future.

Language: Английский

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Evaluating stratospheric ozone and water vapour changes in CMIP6 models from 1850 to 2100

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(6), P. 5015 - 5061

Published: March 31, 2021

Abstract. Stratospheric ozone and water vapour are key components of the Earth system, past future changes to both have important impacts on global regional climate. Here, we evaluate long-term in these species from pre-industrial period (1850) end 21st century Coupled Model Intercomparison Project phase 6 (CMIP6) models under a range emissions scenarios. There is good agreement between CMIP multi-model mean observations for total column (TCO), although there substantial variation individual CMIP6 models. For mean, TCO has increased ∼ 300 DU 1850 305 1960, before rapidly declining 1970s 1980s following use emission halogenated ozone-depleting substances (ODSs). projected return 1960s values by middle SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, SSP5-8.5 scenarios, SSP3-7.0 scenarios be 10 higher than 2100. However, SSP1-1.9 SSP1-1.6 not despite reductions ODSs due decreases tropospheric mixing ratios. This pattern similar patterns, except tropics where most values, either through SSP1-2.6, or lower stratospheric resulting an acceleration Brewer–Dobson circulation other Shared Socioeconomic Pathways (SSPs). In contrast TCO, poorer observed ratios, with underestimating ratios 0.5 ppmv at 70 hPa. tropical stratosphere present-day increase further century. The largest increases (∼ 2 ppmv) simulated highest assumed forcing pathway (e.g. SSP5-8.5). Tropical vapour, lesser extent shows large variations explosive volcanic eruptions.

Language: Английский

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Effective radiative forcing from emissions of reactive gases and aerosols – a multi-model comparison

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(2), P. 853 - 874

Published: Jan. 21, 2021

Abstract. This paper quantifies the pre-industrial (1850) to present-day (2014) effective radiative forcing (ERF) of anthropogenic emissions NOX, volatile organic compounds (VOCs; including CO), SO2, NH3, black carbon, and concentrations methane, N2O ozone-depleting halocarbons, using CMIP6 models. Concentration emission changes reactive species can cause multiple in composition radiatively active species: tropospheric ozone, stratospheric water vapour, secondary inorganic aerosol, methane. Where possible we break down ERFs from each emitted into contributions changes. The are calculated for models that participated AerChemMIP experiments as part project, where relevant model output was available. 1850 2014 multi-model mean (± standard deviations) −1.03 ± 0.37 W m−2 SO2 emissions, −0.25 0.09 carbon (OC), 0.15 0.17 (BC) −0.07 0.01 NH3. For combined aerosols (in piClim-aer experiment) it is −1.01 0.25 m−2. means well-mixed greenhouse gases (including any effects on ozone aerosol chemistry) 0.67 methane (CH4), 0.26 0.07 nitrous oxide (N2O) 0.12 0.2 halocarbons (HC). Emissions precursors nitrogen oxides (NOx), both together (O3) lead 0.14 0.13, 0.20 respectively. differences different reflect complexity their chemistry schemes, especially case captures increased production.

Language: Английский

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A multi-model assessment of the Global Warming Potential of hydrogen

Communications Earth & Environment, Journal Year: 2023, Volume and Issue: 4(1)

Published: June 7, 2023

Abstract With increasing global interest in molecular hydrogen to replace fossil fuels, more attention is being paid potential leakages of into the atmosphere and its environmental consequences. Hydrogen not directly a greenhouse gas, but chemical reactions change abundances gases methane, ozone, stratospheric water vapor, as well aerosols. Here, we use model ensemble five atmospheric chemistry models estimate 100-year time-horizon Global Warming Potential (GWP100) hydrogen. We GWP100 11.6 ± 2.8 (one standard deviation). The uncertainty range covers soil uptake, photochemical production hydrogen, lifetimes hydroxyl radical feedback on methane hydrogen-induced changes are robust across different models. It will be important keep at minimum accomplish benefits switching economy.

Language: Английский

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Future changes in precipitation and temperature over the Yangtze River Basin in China based on CMIP6 GCMs

Atmospheric Research, Journal Year: 2021, Volume and Issue: 264, P. 105828 - 105828

Published: Aug. 25, 2021

Language: Английский

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Evaluation of soil carbon simulation in CMIP6 Earth system models

Biogeosciences, Journal Year: 2022, Volume and Issue: 19(19), P. 4671 - 4704

Published: Oct. 5, 2022

Abstract. The response of soil carbon represents one the key uncertainties in future climate change. ability Earth system models (ESMs) to simulate present-day is therefore vital for reliably estimating global budgets required Paris Agreement targets. In this study CMIP6 ESMs are evaluated against empirical datasets assess each model and related controls: net primary productivity (NPP) turnover time (τs). Comparing with previous generation (CMIP5), a lack consistency modelled remains, particularly underestimation northern high-latitude stocks. There robust improvement simulation NPP compared CMIP5; however, an unrealistically high correlation stocks suggesting potential overestimation long-term terrestrial sink. Additionally, same improvements not seen τs. These results suggest that much uncertainty associated can be attributed below-ground processes, greater emphasis on improving representation processes developments models. would help reduce projected release from soils under change increase confidence different levels warming.

Language: Английский

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Climate change penalty and benefit on surface ozone: a global perspective based on CMIP6 earth system models

Environmental Research Letters, Journal Year: 2022, Volume and Issue: 17(2), P. 024014 - 024014

Published: Jan. 11, 2022

Abstract This work presents an analysis of the effect climate change on surface ozone discussing related penalties and benefits around globe from global modelling perspective based simulations with five CMIP6 (Coupled Model Intercomparison Project Phase 6) Earth System Models. As part AerChemMIP (Aerosol Chemistry Project) all models conducted simulation experiments considering future (ssp370SST) present-day (ssp370pdSST) under same emissions trajectory (SSP3-7.0). A multi-model average benefit −0.96 ± 0.07 ppbv °C −1 is calculated which mainly linked to dominating role enhanced destruction higher water vapour abundances a warmer climate. Over regions remote pollution sources, there robust decline in mean concentration annual basis as well for boreal winter summer varying spatially −0.2 −2 , strongest over tropical oceanic regions. The implication that sources (except Arctic) consistent baseline due warming. However, increases close anthropogenic or natural biogenic volatile organic compounds emission rate ranging regionally 0.2 2 C implying regional penalty Overall, enhances efficiency precursor generate polluted thus magnitude this depends changes considered study within SSP3_7.0 scenario. comparison impact versus combined indicates dominant projecting concentrations scenarios.

Language: Английский

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Tripling of western US particulate pollution from wildfires in a warming climate

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(14)

Published: March 28, 2022

SignificanceRecord-setting fires in the western United States over last decade caused severe air pollution, loss of human life, and property damage. Enhanced drought increased biomass a warmer climate may fuel larger more frequent wildfires coming decades. Applying an empirical statistical model to projected by Earth System Models including climate-ecosystem-socioeconomic interactions, we show that fine particulate pollution US Pacific Northwest could double triple during late summer fall 21st century under intermediate- low-mitigation scenarios. The historic resulting extremes 2017-2020 occur every 3 5 y 21st-century change, posing challenges for quality management threatening public health.

Language: Английский

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Future Population Exposure to Daytime and Nighttime Heat Waves in South Asia

Earth s Future, Journal Year: 2022, Volume and Issue: 10(5)

Published: April 12, 2022

Abstract Climate change is expected to result in more frequent and intense heat waves (HWs) South Asia (SA). The simultaneous increases temperature population will exacerbate the exposure future HWs. Here we estimate daytime nighttime HWs SA using Coupled Model Intercomparison Project 6 (CMIP6) models under four Shared Socioeconomic Pathways (SSPs) during 2061–2100, relative 1975–2014. results show that projected frequency spatial extent of (nighttime) be higher scenario SSP5‐8.5, followed by SSP2‐4.5, SSP3‐7.0, SSP1‐2.6 (SSP5‐8.5, SSP1‐2.6), historical period. approach presented here allows decomposing effects climate on overall exposure. reveal compounding trends significantly escalate Under selected SSPs, total ranges from 185 492 204–555 million people‐event, respectively, with maximum occurring Indo‐Gigantic Plain. wide range exposed populations highlights sensitivity our socioeconomic pathway decisions, emphasizing importance curbing anthropogenic greenhouse gas emissions adopting sustainable urban planning solutions minimize potential health impacts

Language: Английский

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