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| Titel |
Detecting changes in marine responses to ENSO from 850-2100 CE: insights from the ocean carbon cycle |
| VerfasserIn |
Kathrin Keller, Fortunat Joos, Flavio Lehner, Christoph C. Raible |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250105257
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| Publikation (Nr.) |
 EGU/EGU2015-4741.pdf |
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| Zusammenfassung |
| El Niño–Southern Oscillation (ENSO) is the most important mode of natural variability in the
climate system on global scales. It is open whether ENSO varies under climate change, and
how potential changes are best detectable. We investigate ENSO and its influence on
biogeochemical tracers, pH, productivity, and ocean temperature utilizing a continuous
850-2100 CE simulation with the Community Earth System Model. ENSO is represented by
the Niño3.4 index, i.e., the spatial average of SST anomalies in the equatorial Pacific
(5 °S-5 °N, 170-120 °W ). The response of variables is investigated by applying
composite analysis, thereby accounting for nonlinearity of positive and negative
phases of ENSO. The modeled variance in ENSO amplitude is significantly higher
during the Maunder Minimum cold than during the 21st century warm period.
ENSO-driven anomalies in global air-sea CO2 flux and marine productivity are
two to three times lower and ocean tracer anomalies are generally weaker in the
21st century. Significant changes are detectable in both surface and subsurface
waters and are earlier verifiable and more widespread for carbon cycle tracers than
for temperature. The results suggest that multi-tracer data of both physical and
biogeochemical variables might allow an earlier detection of potential changes in
ENSO characteristics than physics-only approaches. This in turn could benefit the
planning and cost-efficient implementation of adaptation and mitigation measures. |
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