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Sensible heat has significantly affected the global hydrological cycle over the historical period.

ABSTRACT: Globally, latent heating associated with a change in precipitation is balanced by changes to atmospheric radiative cooling and sensible heat fluxes. Both components can be altered by climate forcing mechanisms and through climate feedbacks, but the impacts of climate forcing and feedbacks on sensible heat fluxes have received much less attention. Here we show, using a range of climate modelling results, that changes in sensible heat are the dominant contributor to the present global-mean precipitation change since preindustrial time, because the radiative impact of forcings and feedbacks approximately compensate. The model results show a dissimilar influence on sensible heat and precipitation from various drivers of climate change. Due to its strong atmospheric absorption, black carbon is found to influence the sensible heat very differently compared to other aerosols and greenhouse gases. Our results indicate that this is likely caused by differences in the impact on the lower tropospheric stability.

SUBMITTER: Myhre G

PROVIDER: S-EPMC5954152 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Sensible heat has significantly affected the global hydrological cycle over the historical period.

Myhre G G Samset B H BH Hodnebrog Ø Ø Andrews T T Boucher O O Faluvegi G G Fläschner D D Forster P M PM Forster P M PM Kasoar M M Kharin V V Kirkevåg A A Lamarque J-F JF Olivié D D Richardson T B TB Shawki D D Shindell D D Shine K P KP Stjern C W CW Takemura T T Voulgarakis A A

Nature communications 20180515 1

Globally, latent heating associated with a change in precipitation is balanced by changes to atmospheric radiative cooling and sensible heat fluxes. Both components can be altered by climate forcing mechanisms and through climate feedbacks, but the impacts of climate forcing and feedbacks on sensible heat fluxes have received much less attention. Here we show, using a range of climate modelling results, that changes in sensible heat are the dominant contributor to the present global-mean precipi ...[more]

PMID: 29765048

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Dataset Information

Sensible heat has significantly affected the global hydrological cycle over the historical period.

Publications

Sensible heat has significantly affected the global hydrological cycle over the historical period.

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