Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover
Worldwide sea surface temperatures (SST) have increased on average by about 1oC since 1900 with the exception of a region of the North Atlantic subpolar gyre (SPG) near 50oN which has cooled by up to 0.9oC over the same period, generating the negative feature on temperature anomaly maps which has be...
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Online Access: | https://centaur.reading.ac.uk/87865/ https://centaur.reading.ac.uk/87865/1/Allan20JGR.pdf |
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ftunivreading:oai:centaur.reading.ac.uk:87865 2024-05-19T07:35:26+00:00 Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover Allan, David Allan, Richard P. 2020-01-24 text https://centaur.reading.ac.uk/87865/ https://centaur.reading.ac.uk/87865/1/Allan20JGR.pdf en eng Wiley https://centaur.reading.ac.uk/87865/1/Allan20JGR.pdf Allan, D. and Allan, R. P. <https://centaur.reading.ac.uk/view/creators/90000870.html> orcid:0000-0003-0264-9447 (2020) Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover. Journal of Geophysical Research: Oceans, 124 (12). pp. 9040-9052. ISSN 2169-9275 doi: https://doi.org/10.1029/2019JC015379 <https://doi.org/10.1029/2019JC015379> Article PeerReviewed 2020 ftunivreading https://doi.org/10.1029/2019JC015379 2024-05-01T00:23:28Z Worldwide sea surface temperatures (SST) have increased on average by about 1oC since 1900 with the exception of a region of the North Atlantic subpolar gyre (SPG) near 50oN which has cooled by up to 0.9oC over the same period, generating the negative feature on temperature anomaly maps which has been colloquially described by Rahmstorf et al. (2015) as the ‘cold blob’ (abbreviated here CB). This unique long term surface cooling trend is most evident in February but in August net warming is observed even at CB epicentre and the CB itself is reduced to a mere ‘warming hole’. These seasonal changes in the intensity of the CB are the product of two separate factors: (1) a long term winter cooling specific for the CB region which appears to be associated with cooling of Greenland coastal waters in autumn, plausibly linked to summer meltwater from icebergs and sea ice and (2) summer warming effects which derive from (a) dramatic reductions in summer sea ice cover in the sub‐Arctic over the last 30 years that allows enhanced absorption of sunlight by the new open water in summer and (b) an unusual period of increased summer sub‐Arctic ice cover in the early 20th century which lowers the SST baseline measured from 1900, thus increasing the calculated linear rate of change of SST with time. Both of these effects could contribute to the observed Arctic amplification of warming. Article in Journal/Newspaper Arctic Greenland Iceberg* North Atlantic Sea ice Subarctic CentAUR: Central Archive at the University of Reading Journal of Geophysical Research: Oceans 124 12 9040 9052 |
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Open Polar |
collection |
CentAUR: Central Archive at the University of Reading |
op_collection_id |
ftunivreading |
language |
English |
description |
Worldwide sea surface temperatures (SST) have increased on average by about 1oC since 1900 with the exception of a region of the North Atlantic subpolar gyre (SPG) near 50oN which has cooled by up to 0.9oC over the same period, generating the negative feature on temperature anomaly maps which has been colloquially described by Rahmstorf et al. (2015) as the ‘cold blob’ (abbreviated here CB). This unique long term surface cooling trend is most evident in February but in August net warming is observed even at CB epicentre and the CB itself is reduced to a mere ‘warming hole’. These seasonal changes in the intensity of the CB are the product of two separate factors: (1) a long term winter cooling specific for the CB region which appears to be associated with cooling of Greenland coastal waters in autumn, plausibly linked to summer meltwater from icebergs and sea ice and (2) summer warming effects which derive from (a) dramatic reductions in summer sea ice cover in the sub‐Arctic over the last 30 years that allows enhanced absorption of sunlight by the new open water in summer and (b) an unusual period of increased summer sub‐Arctic ice cover in the early 20th century which lowers the SST baseline measured from 1900, thus increasing the calculated linear rate of change of SST with time. Both of these effects could contribute to the observed Arctic amplification of warming. |
format |
Article in Journal/Newspaper |
author |
Allan, David Allan, Richard P. |
spellingShingle |
Allan, David Allan, Richard P. Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover |
author_facet |
Allan, David Allan, Richard P. |
author_sort |
Allan, David |
title |
Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover |
title_short |
Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover |
title_full |
Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover |
title_fullStr |
Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover |
title_full_unstemmed |
Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover |
title_sort |
seasonal changes in the north atlantic cold anomaly: the influence of cold surface waters from coastal greenland and warming trends associated with variations in subarctic sea ice cover |
publisher |
Wiley |
publishDate |
2020 |
url |
https://centaur.reading.ac.uk/87865/ https://centaur.reading.ac.uk/87865/1/Allan20JGR.pdf |
genre |
Arctic Greenland Iceberg* North Atlantic Sea ice Subarctic |
genre_facet |
Arctic Greenland Iceberg* North Atlantic Sea ice Subarctic |
op_relation |
https://centaur.reading.ac.uk/87865/1/Allan20JGR.pdf Allan, D. and Allan, R. P. <https://centaur.reading.ac.uk/view/creators/90000870.html> orcid:0000-0003-0264-9447 (2020) Seasonal changes in the North Atlantic cold anomaly: the influence of cold surface waters from coastal Greenland and warming trends associated with variations in subarctic sea ice cover. Journal of Geophysical Research: Oceans, 124 (12). pp. 9040-9052. ISSN 2169-9275 doi: https://doi.org/10.1029/2019JC015379 <https://doi.org/10.1029/2019JC015379> |
op_doi |
https://doi.org/10.1029/2019JC015379 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
124 |
container_issue |
12 |
container_start_page |
9040 |
op_container_end_page |
9052 |
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1799474116001005568 |