The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate
While rapid changes in Arctic climate over recent decades are widely documented, the importance of different driving mechanisms is still debated. A previous study proposed a causal connection between recent tropical Pacific sea surface temperature (SST) trends and circulation changes over northern C...
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American Meteorological Society
2020
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ftnerc:oai:nora.nerc.ac.uk:527830 2024-02-11T10:00:47+01:00 The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate McCrystall, Michelle R. Hosking, J. Scott White, Ian P. Maycock, Amanda C. 2020-06-15 text http://nora.nerc.ac.uk/id/eprint/527830/ https://nora.nerc.ac.uk/id/eprint/527830/1/jcli-d-19-0456.1.pdf https://journals.ametsoc.org/doi/full/10.1175/JCLI-D-19-0456.1 en eng American Meteorological Society https://nora.nerc.ac.uk/id/eprint/527830/1/jcli-d-19-0456.1.pdf McCrystall, Michelle R.; Hosking, J. Scott orcid:0000-0002-3646-3504 White, Ian P.; Maycock, Amanda C. 2020 The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate. Journal of Climate, 33 (12). 5103-5121. https://doi.org/10.1175/JCLI-D-19-0456.1 <https://doi.org/10.1175/JCLI-D-19-0456.1> Publication - Article PeerReviewed 2020 ftnerc https://doi.org/10.1175/JCLI-D-19-0456.1 2024-01-19T00:03:17Z While rapid changes in Arctic climate over recent decades are widely documented, the importance of different driving mechanisms is still debated. A previous study proposed a causal connection between recent tropical Pacific sea surface temperature (SST) trends and circulation changes over northern Canada and Greenland (NCG). Here, using the HadGEM3-A model, we perform a suite of sensitivity experiments to investigate the influence of tropical SSTs on winter atmospheric circulation over NCG. The experiments are forced with observed SST changes between an “early” (1979–88) and “late” period (2003–12) and applied across the entire tropics (TropSST), the tropical Pacific (PacSST), and the tropical Atlantic (AtlSST). In contrast to the previous study, all three experiments show a negative 200-hPa eddy geopotential height (Z200) anomaly over NCG in winter, which is similar to the response in AMIP experiments from four other climate models. The positive Z200 NCG anomaly in ERA-Interim between the two periods is inside the bounds of internal variability estimated from bootstrap sampling. The NCG circulation anomaly in the TropSST experiment is associated with a Rossby wave train originating from the tropical Pacific, with an important contribution coming from the tropical Atlantic SSTs connected via an atmospheric bridge through the tropical Pacific. This generates anomalous upper-level convergence and a positive Rossby wave source anomaly near the North Pacific jet exit region. Hence, while a tropics–Arctic teleconnection is evident, its influence on recent Arctic regional climate differs from observed changes and warrants further research. Article in Journal/Newspaper Arctic Greenland Natural Environment Research Council: NERC Open Research Archive Arctic Canada Greenland Pacific Journal of Climate 33 12 5103 5121 |
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Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
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ftnerc |
language |
English |
description |
While rapid changes in Arctic climate over recent decades are widely documented, the importance of different driving mechanisms is still debated. A previous study proposed a causal connection between recent tropical Pacific sea surface temperature (SST) trends and circulation changes over northern Canada and Greenland (NCG). Here, using the HadGEM3-A model, we perform a suite of sensitivity experiments to investigate the influence of tropical SSTs on winter atmospheric circulation over NCG. The experiments are forced with observed SST changes between an “early” (1979–88) and “late” period (2003–12) and applied across the entire tropics (TropSST), the tropical Pacific (PacSST), and the tropical Atlantic (AtlSST). In contrast to the previous study, all three experiments show a negative 200-hPa eddy geopotential height (Z200) anomaly over NCG in winter, which is similar to the response in AMIP experiments from four other climate models. The positive Z200 NCG anomaly in ERA-Interim between the two periods is inside the bounds of internal variability estimated from bootstrap sampling. The NCG circulation anomaly in the TropSST experiment is associated with a Rossby wave train originating from the tropical Pacific, with an important contribution coming from the tropical Atlantic SSTs connected via an atmospheric bridge through the tropical Pacific. This generates anomalous upper-level convergence and a positive Rossby wave source anomaly near the North Pacific jet exit region. Hence, while a tropics–Arctic teleconnection is evident, its influence on recent Arctic regional climate differs from observed changes and warrants further research. |
format |
Article in Journal/Newspaper |
author |
McCrystall, Michelle R. Hosking, J. Scott White, Ian P. Maycock, Amanda C. |
spellingShingle |
McCrystall, Michelle R. Hosking, J. Scott White, Ian P. Maycock, Amanda C. The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate |
author_facet |
McCrystall, Michelle R. Hosking, J. Scott White, Ian P. Maycock, Amanda C. |
author_sort |
McCrystall, Michelle R. |
title |
The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate |
title_short |
The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate |
title_full |
The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate |
title_fullStr |
The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate |
title_full_unstemmed |
The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate |
title_sort |
impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate |
publisher |
American Meteorological Society |
publishDate |
2020 |
url |
http://nora.nerc.ac.uk/id/eprint/527830/ https://nora.nerc.ac.uk/id/eprint/527830/1/jcli-d-19-0456.1.pdf https://journals.ametsoc.org/doi/full/10.1175/JCLI-D-19-0456.1 |
geographic |
Arctic Canada Greenland Pacific |
geographic_facet |
Arctic Canada Greenland Pacific |
genre |
Arctic Greenland |
genre_facet |
Arctic Greenland |
op_relation |
https://nora.nerc.ac.uk/id/eprint/527830/1/jcli-d-19-0456.1.pdf McCrystall, Michelle R.; Hosking, J. Scott orcid:0000-0002-3646-3504 White, Ian P.; Maycock, Amanda C. 2020 The impact of changes in tropical sea surface temperatures over 1979–2012 on northern hemisphere high-latitude climate. Journal of Climate, 33 (12). 5103-5121. https://doi.org/10.1175/JCLI-D-19-0456.1 <https://doi.org/10.1175/JCLI-D-19-0456.1> |
op_doi |
https://doi.org/10.1175/JCLI-D-19-0456.1 |
container_title |
Journal of Climate |
container_volume |
33 |
container_issue |
12 |
container_start_page |
5103 |
op_container_end_page |
5121 |
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1790596509708845056 |