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The Indo‐Pacific Warm Pool (IPWP) exerts a major influence on global atmospheric circulation, yet the drivers of late Pleistocene IPWP sea surface temperature (SST) variability remain debated. To evaluate how IPWP temperature responds to different climate forcings, we present new SST records spanning the past 650 kyr based on three independent proxies—, , and Mg/Ca—from International Ocean Discovery Program Site U1482, located off northwestern Australia at the southernmost margin of the IPWP. Core top samples suggest that and Mg/Ca are biased toward austral summer, while is elevated under low‐nutrient conditions. Down‐core, all proxies exhibit coherent glacial–interglacial SST variations of ∼5C, although is affected by nutrient stress during interglacials. The record shows relatively warm conditions during Marine Isotope Stage 6 compared to other glacial intervals, but this is not observed in the or Mg/Ca records. Total alkenone concentration, reflecting paleo‐productivity, indicate enhanced productivity during glacial intervals and reduced productivity during interglacials. The SST proxy records are in phase with greenhouse gas and ice volume in the 100 and 41 kyr orbital bands, emphasizing tropical‐high latitude climate coupling, while local precession forcing impacts seasonal SSTs. Productivity variations track both glacial‐interglacial cycles and precession‐driven changes in wind‐driven upwelling and surface current intensity in the Indo‐Pacific. Our regional synthesis highlights sea‐level and shelf exposure as key drivers of IPWP SST patterns, with a more pronounced precession influence at the southern IPWP margin. Our findings demonstrate that both glacial‐interglacial cycles and precession govern SST and productivity variations in the IPWP.
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The 1991–2020 sea surface temperature normals
Abstract The 1991–2020 climate normals for sea surface temperature (SST) are computed based on the NOAA Daily Optimum Interpolation SST dataset. This is the first time that high‐resolution SST normals with global coverage can be achieved in the satellite SST era. Normals are one of the fundamental parameters in describing and understanding weather and climate and provide decision‐making information to industry, public, and scientific communities. This product suite includes SST mean, standard deviation, count and extreme parameters at daily, monthly, seasonal and annual time scales on 0.25° spatial grids. The main feature of the SST mean state revealed by the normals is that in the Tropics, the Indo‐Pacific Ocean is dominated by the warm pool (SST ≥ 28°C) while the eastern Pacific is characterized by the cold tongue (SST ≤ 24°C); in the midlatitudes, SSTs are in zonal patterns with high meridional gradients. Daily SST standard deviations are generally small (<1.0°C) except in frontal zones (>1.5°C) mostly associated with ocean currents such as the Gulf Stream, Kuroshio and Equatorial Currents. Compared to the 1982–2011 climatology, the 1991–2020 mean SSTs increased over most global areas but obvious cooling is seen in the Southern Ocean, eastern tropical South Pacific Ocean and North Atlantic warming hole. The Indo‐Pacific warm pool (IPWP) is found to have strengthened in both intensity and coverage since 1982–2011. By a count parameter criterion of ≥300 days annually with SST ≥ 28°C, the IPWP coverage increased 33% from 1982–2011 to 1991–2020. The global mean SST of 1991–2020 is warmer than that of 1982–2011, and the warming rate over 1991–2020 doubles that over 1901–2020.
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- Award ID(s):
- 1948952
- PAR ID:
- 10507993
- Publisher / Repository:
- Royal Meteorological Society
- Date Published:
- Journal Name:
- International Journal of Climatology
- Edition / Version:
- 1
- Volume:
- 44
- Issue:
- 2
- ISSN:
- 0899-8418
- Page Range / eLocation ID:
- 668 to 685
- Subject(s) / Keyword(s):
- sea surface temperature climate variability remote sensing
- Format(s):
- Medium: X Size: 22mb Other: pdf
- Size(s):
- 22mb
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/joc.8350
