TY - JOUR
T1 - Climatology of hot events in the western equatorial Pacific
AU - Wirasatriya, Anindya
AU - Kawamura, Hiroshi
AU - Shimada, Teruhisa
AU - Hosoda, Kohtaro
N1 - Funding Information:
JRA-25/JCDAS data were made available by a cooperative research project of the Japan Meteorological Agency (JMA) and the Central Research Institute of Electric Power Industry. ISCCP-FD data were provided courtesy of the NASA Goddard Institute for Space Studies. The global ocean heat flux products were provided by the WHOI OAFlux project ( http://oaflux.whoi.edu ), as funded by the NOAA Climate Observations and Monitoring (COM) program. TAO/TRITON buoy data were distributed by the TAO Project Office of NOAA/PMEL. NOAA_OI_SST_V2 data were provided by the NOAA/OAR/ESRL PSD (Boulder, CO, USA), via their website at http://www.esrl.noaa.gov/psd/ . Merged satellite and in situ data on global daily sea surface temperature were from the Japan Meteorological Agency (JMA), and are available at http://near-goos1.jodc.go.jp/ . The first author thanks the Directorate General of Higher Education, Indonesian Republic, for a Ph.D. scholarship.
Publisher Copyright:
© 2014, The Oceanographic Society of Japan and Springer Japan.
PY - 2015/2
Y1 - 2015/2
N2 - We investigated the climatology of hot events (HEs) in the western equatorial Pacific. HEs are characterized by well-organized high sea surface temperatures (SSTs). We proposed a method for identifying HEs using a space–time-dependent threshold with a minimum areal size of 2 × 106 km2, and with a duration (period) of >6 days. We thus identified 71 HEs from the optimally interpolated SST dataset during 2003–2011. Their mean duration, areal size, and amplitude were 18.14 days, 6.30 × 106 km2, and 0.33 °C, respectively. On average, the HEs developed more slowly than they decayed. They were distributed within the equatorial band to the subtropical Pacific (20°S–30°N), with an eastward extension to 150°W. In particular, the HEs occurred most frequently along the northern coasts of New Guinea and the Solomon Islands to 180°E. Seasonal variation in the HE distribution was observed: a northward shift during boreal summer and a southward shift during boreal winter. The distribution of HE occurrences corresponded to the climatological SST of the western Pacific warm pool. HEs occurred under conditions of low wind speeds (~2.56 m/s) and high levels of solar radiation (~225 W/m2). However, since the high levels of solar radiation occurred over the entire area of the western equatorial Pacific during HE periods, the low wind speed distribution became a key factor in the occurrence of HEs in the western equatorial Pacific. Seasonal shifts in wind speed and solar radiation were found to influence the seasonal shift in HE distribution.
AB - We investigated the climatology of hot events (HEs) in the western equatorial Pacific. HEs are characterized by well-organized high sea surface temperatures (SSTs). We proposed a method for identifying HEs using a space–time-dependent threshold with a minimum areal size of 2 × 106 km2, and with a duration (period) of >6 days. We thus identified 71 HEs from the optimally interpolated SST dataset during 2003–2011. Their mean duration, areal size, and amplitude were 18.14 days, 6.30 × 106 km2, and 0.33 °C, respectively. On average, the HEs developed more slowly than they decayed. They were distributed within the equatorial band to the subtropical Pacific (20°S–30°N), with an eastward extension to 150°W. In particular, the HEs occurred most frequently along the northern coasts of New Guinea and the Solomon Islands to 180°E. Seasonal variation in the HE distribution was observed: a northward shift during boreal summer and a southward shift during boreal winter. The distribution of HE occurrences corresponded to the climatological SST of the western Pacific warm pool. HEs occurred under conditions of low wind speeds (~2.56 m/s) and high levels of solar radiation (~225 W/m2). However, since the high levels of solar radiation occurred over the entire area of the western equatorial Pacific during HE periods, the low wind speed distribution became a key factor in the occurrence of HEs in the western equatorial Pacific. Seasonal shifts in wind speed and solar radiation were found to influence the seasonal shift in HE distribution.
KW - High SST
KW - Hot event
KW - Merged SST
KW - Western Pacific warm pool
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U2 - 10.1007/s10872-014-0263-3
DO - 10.1007/s10872-014-0263-3
M3 - Article
AN - SCOPUS:84925502723
VL - 71
SP - 77
EP - 90
JO - Journal of Oceanography
JF - Journal of Oceanography
SN - 0916-8370
IS - 1
ER -