Journal article
Large‐Scale Reductions in Terrestrial Carbon Uptake Following Central Pacific El Niño
Geophysical research letters, Vol.48(7), e2020GL092367
04/16/2021
DOI: 10.1029/2020GL092367
Abstract
The El Niño–Southern Oscillation (ENSO) affects global climate and ecosystems, but a recent shift toward more frequent central Pacific (CP) El Niño events could alter these relationships. Here, we show strong responses of the terrestrial carbon cycle to CP ENSO, exceeding even those to canonical eastern Pacific (EP) ENSO. Annual GPP of both global tropical forests and semiarid ecosystems were reduced by ∼0.3–0.5 Pg C yr−1 K−1 increase in CP sea surface temperatures (SSTs), which also reduced net ecosystem production of key tropical and semiarid regions like the Amazon and Australia, but with smaller (and generally not significant) responses to EP SSTs. Given these large negative responses of ecosystem production to CP SSTs, our results suggest that a recent shift toward CP‐dominated ENSO events could further alter Earth's terrestrial carbon cycle, especially when coupled with possible increases in ENSO amplitude with continued warming.
Plain Language Summary
El Niño (warmer‐than‐normal tropical Pacific sea surface temperatures [SSTs]) usually causes warming of air temperatures across most of Earth's surface and enhanced dryness in many tropical regions, while La Niña (cooler‐than‐normal tropical Pacific SSTs) usually has the opposite effect. Global photosynthesis is usually reduced following El Niño but enhanced following La Niña. However, not all El Niño and La Niña events are the same: some are dominated by temperature changes in the eastern Pacific (EP), some by changes in the central Pacific (CP), and some by mixtures of the two. We show that global photosynthesis, especially in tropical forests and semiarid ecosystems, is particularly sensitive to CP SSTs, likely reflecting enhanced air temperature and dryness throughout most of the tropics following CP El Niño. Forecasts of both climate and vegetation activity often rely on knowledge of El Niño, but these forecasts might be improved using information on which “type” of El Niño is dominant. Further, CP El Niños have recently become more common than EP El Niños.
Key Points
Responses of gross primary production to central Pacific El Niño are generally stronger and more coherent than to eastern Pacific El Niño
Tropical forests and semiarid ecosystems in South America, Africa, and Australia respond most negatively to central Pacific El Niño
The Sahel was the only region with consistently stronger responses to eastern than to central Pacific sea surface temperatures
Details
- Title: Subtitle
- Large‐Scale Reductions in Terrestrial Carbon Uptake Following Central Pacific El Niño
- Creators
- Matthew P. Dannenberg - University of IowaWilliam K. Smith - University of ArizonaYulong Zhang - University of Tennessee at KnoxvilleConghe Song - University of North Carolina at Chapel HillDeborah N. Huntzinger - Northern Arizona UniversityDavid J. P. Moore - University of Arizona
- Resource Type
- Journal article
- Publication Details
- Geophysical research letters, Vol.48(7), e2020GL092367
- DOI
- 10.1029/2020GL092367
- ISSN
- 0094-8276
- eISSN
- 1944-8007
- Number of pages
- 11
- Grant note
- Department of Defense SERDP (RC18‐1322) National Aeronautics and Space Administration (NASA) (80NSSC20K1805) National Aeronautics and Space Administration (NASA) (NNX17AE69G)
- Language
- English
- Date published
- 04/16/2021
- Academic Unit
- Geographical and Sustainability Sciences
- Record Identifier
- 9984259636102771
Metrics
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