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| Titel |
A Real-time Ocean Reanalyses Intercomparison Project in the Context of Tropical Pacific Observing System and ENSO Monitoring |
| VerfasserIn |
Yan Xue, Caihong Wen, Arun Kumar, Magdalena Balmaseda, Yosuke Fujii, Oscar Alves, Matthew Martin, Xiaosong Yang, Guillaume Vernieres, Charles Desporters, Tong Lee, Isabella Ascione, Rich Gudgel, Ichiro Ishikawa |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250144501
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| Publikation (Nr.) |
 EGU/EGU2017-8336.pdf |
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| Zusammenfassung |
| An ensemble of nine operational ocean reanalyses (ORAs) is now routinely collected, and is
used to monitor the consistency across the tropical Pacific temperature analyses in real-time
in support of ENSO monitoring, diagnostics, and prediction. The ensemble approach allows a
more reliable estimate of the signal as well as an estimation of the noise among
analyses. The real-time estimation of signal-to-noise ratio assists the prediction of
ENSO.
The ensemble spread, as a measure of uncertainties in ORAs, is shown to partially
link to the Tropical Pacific Observing System (TPOS). The full deployment of the
TAO array significantly reduced the uncertainties among temperature analyses in
the equatorial Pacific, thus clearly highlighting the positive influence of the TAO
data on constraining ocean analyses. The availability of the Argo data helped to
reduce the analysis uncertainty north of 8oN and south of 8oS significantly. The
uncertainties in total temperature reduced significantly in 2015 due to the recovery of the
TAO/TRITON array to approach the value before the TAO crisis in 2012. However, the
uncertainties in anomalous temperature still remained much higher than the pre-2012
value, probably due to uncertainties in the reference climatology. This highlights
the importance of the long- term stability of the observing system for anomaly
monitoring.
The influences of the TAO data loss on the estimation of D20 anomalies during
2012-2015 were assessed. In 2012 and 2013, the signal was weak, while the noise was
comparable to the signal in the eastern equatorial Pacific where many TAO moorings were
down. The 2015/16 El Nin∼o was very well observed due to the recovery of the TAO
moorings by the end of 2014, and the signal-to-noise ratio in D20 anomalies was relatively
high. The ensemble ORAs have been used to study the characteristics of the evolution of the
2015/16 El Niño and place it in the context of historical ENSO events since 1979. |
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