Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation
Studies conducted by the UK Met Office reported significant skill in predicting the winter North Atlantic Oscillation (NAO) index with their seasonal prediction system. At the same time, a very low signal‐to‐noise ratio was observed, as measured using the “ratio of predictable components” (RPC) metr...
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crwiley:10.1002/qj.3414 2024-09-15T18:21:54+00:00 Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation Strommen, Kristian Palmer, Tim N. Horizon 2020 Framework Programme 2018 http://dx.doi.org/10.1002/qj.3414 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fqj.3414 https://onlinelibrary.wiley.com/doi/pdf/10.1002/qj.3414 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/qj.3414 https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/qj.3414 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Quarterly Journal of the Royal Meteorological Society volume 145, issue 718, page 147-163 ISSN 0035-9009 1477-870X journal-article 2018 crwiley https://doi.org/10.1002/qj.3414 2024-08-13T04:16:45Z Studies conducted by the UK Met Office reported significant skill in predicting the winter North Atlantic Oscillation (NAO) index with their seasonal prediction system. At the same time, a very low signal‐to‐noise ratio was observed, as measured using the “ratio of predictable components” (RPC) metric. We analyse both the skill and signal‐to‐noise ratio using a new statistical toy model, which assumes NAO predictability is driven by regime dynamics. It is shown that if the system is approximately bimodal in nature, with the model consistently underestimating the level of regime persistence each season, then both the high skill and high RPC value of the Met Office hindcasts can easily be reproduced. Underestimation of regime persistence could be attributable to any number of sources of model error, including imperfect regime structure or errors in the propagation of teleconnections. In particular, a high RPC value for a seasonal mean prediction may be expected even if the model's internal level of noise is realistic. Article in Journal/Newspaper North Atlantic North Atlantic oscillation Wiley Online Library Quarterly Journal of the Royal Meteorological Society 145 718 147 163 |
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Open Polar |
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Wiley Online Library |
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crwiley |
language |
English |
description |
Studies conducted by the UK Met Office reported significant skill in predicting the winter North Atlantic Oscillation (NAO) index with their seasonal prediction system. At the same time, a very low signal‐to‐noise ratio was observed, as measured using the “ratio of predictable components” (RPC) metric. We analyse both the skill and signal‐to‐noise ratio using a new statistical toy model, which assumes NAO predictability is driven by regime dynamics. It is shown that if the system is approximately bimodal in nature, with the model consistently underestimating the level of regime persistence each season, then both the high skill and high RPC value of the Met Office hindcasts can easily be reproduced. Underestimation of regime persistence could be attributable to any number of sources of model error, including imperfect regime structure or errors in the propagation of teleconnections. In particular, a high RPC value for a seasonal mean prediction may be expected even if the model's internal level of noise is realistic. |
author2 |
Horizon 2020 Framework Programme |
format |
Article in Journal/Newspaper |
author |
Strommen, Kristian Palmer, Tim N. |
spellingShingle |
Strommen, Kristian Palmer, Tim N. Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation |
author_facet |
Strommen, Kristian Palmer, Tim N. |
author_sort |
Strommen, Kristian |
title |
Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation |
title_short |
Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation |
title_full |
Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation |
title_fullStr |
Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation |
title_full_unstemmed |
Signal and noise in regime systems: A hypothesis on the predictability of the North Atlantic Oscillation |
title_sort |
signal and noise in regime systems: a hypothesis on the predictability of the north atlantic oscillation |
publisher |
Wiley |
publishDate |
2018 |
url |
http://dx.doi.org/10.1002/qj.3414 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fqj.3414 https://onlinelibrary.wiley.com/doi/pdf/10.1002/qj.3414 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/qj.3414 https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/qj.3414 |
genre |
North Atlantic North Atlantic oscillation |
genre_facet |
North Atlantic North Atlantic oscillation |
op_source |
Quarterly Journal of the Royal Meteorological Society volume 145, issue 718, page 147-163 ISSN 0035-9009 1477-870X |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/qj.3414 |
container_title |
Quarterly Journal of the Royal Meteorological Society |
container_volume |
145 |
container_issue |
718 |
container_start_page |
147 |
op_container_end_page |
163 |
_version_ |
1810460938162143232 |