Early-twentieth-century cold bias in ocean surface temperature observations

Sebastian Sippel (), Elizabeth C. Kent, Nicolai Meinshausen, Duo Chan, Christopher Kadow, Raphael Neukom, Erich M. Fischer, Vincent Humphrey, Robert Rohde, Iris Vries and Reto Knutti
Additional contact information
Sebastian Sippel: Leipzig University
Elizabeth C. Kent: National Oceanography Centre
Nicolai Meinshausen: ETH Zürich
Duo Chan: University of Southampton
Christopher Kadow: Deutsches Klimarechenzentrum GmbH
Raphael Neukom: WSL Institute for Snow and Avalanche Research SLF
Erich M. Fischer: ETH Zürich
Vincent Humphrey: Federal Office of Meteorology and Climatology MeteoSwiss
Robert Rohde: Berkeley Earth
Iris Vries: ETH Zürich
Reto Knutti: ETH Zürich

Nature, 2024, vol. 635, issue 8039, 618-624

Abstract: Abstract The observed temperature record, which combines sea surface temperatures with near-surface air temperatures over land, is crucial for understanding climate variability and change1–4. However, early records of global mean surface temperature are uncertain owing to changes in measurement technology and practice, partial documentation5–8, and incomplete spatial coverage9. Here we show that existing estimates of ocean temperatures in the early twentieth century (1900–1930) are too cold, based on independent statistical reconstructions of the global mean surface temperature from either ocean or land data. The ocean-based reconstruction is on average about 0.26 °C colder than the land-based one, despite very high agreement in all other periods. The ocean cold anomaly is unforced, and internal variability in climate models cannot explain the observed land–ocean discrepancy. Several lines of evidence based on attribution, timescale analysis, coastal grid cells and palaeoclimate data support the argument of a substantial cold bias in the observed global sea-surface-temperature record in the early twentieth century. Although estimates of global warming since the mid-nineteenth century are not affected, correcting the ocean cold bias would result in a more modest early-twentieth-century warming trend10, a lower estimate of decadal-scale variability inferred from the instrumental record3, and better agreement between simulated and observed warming than existing datasets suggest2.

Date: 2024
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/s41586-024-08230-1 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:635:y:2024:i:8039:d:10.1038_s41586-024-08230-1

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-024-08230-1

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().