Timescale Dependence of the Precipitation Response to CO ₂ ‐Induced Warming in Millennial‐Length Climate Simulations

Journal Article · 06 November 2024 · Geophysical Research Letters

DOI: https://doi.org/10.1029/2024GL111609 · OSTI ID:2476586

Him (Kinen) Kao, Wing ^[1]; Pendergrass, Angeline G.  ^[2]

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1. Department of Earth and Atmospheric Sciences Cornell University Ithaca NY USA
2. Department of Earth and Atmospheric Sciences Cornell University Ithaca NY USA, National Center for Atmospheric Research Boulder CO USA

Abstract Previous work has shown that estimates of climate sensitivity vary over time in response to abrupt CO ₂ forcing in climate model simulations. The energy fluxes that drive warming in response to increasing CO ₂ also influence precipitation, which prompts the question: Does the precipitation response therefore also vary over time? We investigate by examining the response of precipitation to warming forced by greenhouse gases—the hydrological sensitivity—in a set of millennial‐length climate simulations with multiple climate models, Long Run Model Intercomparison Project (LongRunMIP). We compare hydrological sensitivity calculated from three different timescales of the simulations: years 1–20, 21–150, and 151–1000. We show that the hydrological sensitivity lacks a consistent dependence on timescale, in contrast to climate sensitivity. Decomposition of the surface energy budget reveals that the relative muting of the multi‐model mean hydrological sensitivity is driven by surface downwelling shortwave flux.

• Sponsoring Organization: USDOE
• Grant/Contract Number: NONE; SC0022070
• OSTI ID: 2476586
• Journal Information: Geophysical Research Letters, Journal Name: Geophysical Research Letters Journal Issue: 21 Vol. 51; ISSN 0094-8276
• Publisher: American Geophysical Union (AGU)Copyright Statement
• Country of Publication: United States
• Language: English