{"id":1178,"date":"2023-07-03T02:21:09","date_gmt":"2023-07-03T01:21:09","guid":{"rendered":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/?page_id=1178"},"modified":"2023-07-03T02:21:09","modified_gmt":"2023-07-03T01:21:09","slug":"abstract230","status":"publish","type":"page","link":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/","title":{"rendered":"Abstract 230"},"content":{"rendered":"

[vc_row][vc_column][vc_column_text]Abstract ID:<\/strong> 230<\/p>\n

Relating the properties of quasi-stationary Rossby waves to the jet that they live on<\/h2>\n

Lead Author:<\/strong> John Methven
\nUniversity of Reading, United Kingdom
\n<\/span><\/p>\n

Keywords:<\/strong> Persistent weather, Modes of variability, Wave activity, Jetstream, Phase speed<\/p>\n

Abstract: <\/strong>In recent decades, western Europe has seen a number of extreme
\nseasons. For example, anomalously high precipitation totals for the
\nsummers of 2007 and 2012 as well as the exceptionally high temperature
\nof summer 2003 and the coldness of winter 2009\/10. One common feature
\nin all these examples is the existence of persistent, near stationary
\nRossby wave patterns on the tropopause. Here a rigorous framework is
\nused to extract these “”slow modes of variability”” from
\ndata in such a way that each mode has an intrinsic phase speed related
\nonly to its spatial structure, in a similar way that a bell rings with a
\ncharacteristic note. The phase speed is derived from global
\nconservation properties. The question addressed here is how these slow
\nmodes of variability relate to the structure of the background state jet
\nthat they live on.<\/p>\n

Idealised experiments using a global primitive equation model are
\nconstructed where the only forcing is a weak relaxation to a zonally
\nsymmetric balanced background state which includes a sloping tropopause
\nand westerly jet with a latitude that can be controlled by a single parameter.
\nThe jet is baroclinically unstable and so wave activity is sustained through
\nrepeated growth of baroclinic waves and their nonlinear life cycles.
\nModes of variability in the perturbations are extracted from global data
\nusing the empirical normal mode (ENM) technique. This amounts to
\nEOF analysis using pseudomomentum (wave activity) as the norm.
\nFor a linear system the ENMs would equal the dynamical
\nnormal modes since they are also orthogonal under this norm. Although
\nthe system is nonlinear, only a few ENMs dominate the variability and
\nthe ratio of pseudoenergy to pseudomomentum yields a unique phase
\nspeed for each. It is shown how the properties of the dominant modes
\ndepend on the quasi-equilibrium background state jet strength and latitude.
\nIn this way seasons with anomalously persistent mid-latitude Rossby wave
\nactivity may be related to the interannual variability in the background
\nstate zonal flow.<\/p>\n

Co-authors:
\n<\/strong>Dominic Jones (University of Albany)
\nThomas Frame (University of Reading)
\nPaul Berrisford (ECMWF)[\/vc_column_text][vc_separator][\/vc_column][\/vc_row][vc_row][vc_column width=”1\/6″][vc_single_image image=”344″ img_size=”full” onclick=”custom_link” link=”http:\/\/s2sprediction.net\/”][\/vc_column][vc_column width=”1\/6″][vc_single_image image=”345″ img_size=”full” onclick=”custom_link” link=”https:\/\/public.wmo.int\/en”][\/vc_column][vc_column width=”1\/6″][vc_single_image image=”346″ img_size=”full” onclick=”custom_link” link=”https:\/\/community.wmo.int\/activity-areas\/wwrp”][\/vc_column][vc_column width=”1\/6″][vc_single_image image=”347″ img_size=”full” onclick=”custom_link” link=”https:\/\/www.wcrp-climate.org\/”][\/vc_column][vc_column width=”1\/6″][vc_single_image image=”348″ img_size=”full”][\/vc_column][vc_column width=”1\/6″][vc_single_image image=”349″ img_size=”full” onclick=”custom_link” link=”https:\/\/www.reading.ac.uk\/”][\/vc_column][\/vc_row]<\/p>\n","protected":false},"excerpt":{"rendered":"

[vc_row][vc_column][vc_column_text]Abstract ID: 230 Relating the properties of quasi-stationary Rossby waves to the jet that they live on Lead Author: John Methven University of Reading, United Kingdom Keywords: Persistent weather, Modes…Read More ><\/a><\/p>\n","protected":false},"author":145,"featured_media":0,"parent":528,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"__cvm_playback_settings":[],"__cvm_video_id":"","footnotes":""},"coauthors":[13],"class_list":["post-1178","page","type-page","status-publish","hentry"],"acf":[],"yoast_head":"\nAbstract 230 - WWRP\/WCRP S2S Summit 2023<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Abstract 230 - WWRP\/WCRP S2S Summit 2023\" \/>\n<meta property=\"og:description\" content=\"[vc_row][vc_column][vc_column_text]Abstract ID: 230 Relating the properties of quasi-stationary Rossby waves to the jet that they live on Lead Author: John Methven University of Reading, United Kingdom Keywords: Persistent weather, Modes...Read More >\" \/>\n<meta property=\"og:url\" content=\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/\" \/>\n<meta property=\"og:site_name\" content=\"WWRP\/WCRP S2S Summit 2023\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Estimated reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n\t<meta name=\"twitter:label2\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data2\" content=\"Robert Lee\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/\",\"url\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/\",\"name\":\"Abstract 230 - WWRP\/WCRP S2S Summit 2023\",\"isPartOf\":{\"@id\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/#website\"},\"datePublished\":\"2023-07-03T01:21:09+00:00\",\"dateModified\":\"2023-07-03T01:21:09+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/#breadcrumb\"},\"inLanguage\":\"en-GB\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Programme\",\"item\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Abstract 230\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/#website\",\"url\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/\",\"name\":\"WWRP\/WCRP S2S Summit 2023\",\"description\":\"Advancing Sub-seasonal to Seasonal Predictions and their Applications\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/research.reading.ac.uk\/s2s-summit2023\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-GB\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Abstract 230 - WWRP\/WCRP S2S Summit 2023","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/","og_locale":"en_GB","og_type":"article","og_title":"Abstract 230 - WWRP\/WCRP S2S Summit 2023","og_description":"[vc_row][vc_column][vc_column_text]Abstract ID: 230 Relating the properties of quasi-stationary Rossby waves to the jet that they live on Lead Author: John Methven University of Reading, United Kingdom Keywords: Persistent weather, Modes...Read More >","og_url":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/","og_site_name":"WWRP\/WCRP S2S Summit 2023","twitter_card":"summary_large_image","twitter_misc":{"Estimated reading time":"2 minutes","Written by":"Robert Lee"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/","url":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/","name":"Abstract 230 - WWRP\/WCRP S2S Summit 2023","isPartOf":{"@id":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/#website"},"datePublished":"2023-07-03T01:21:09+00:00","dateModified":"2023-07-03T01:21:09+00:00","breadcrumb":{"@id":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/#breadcrumb"},"inLanguage":"en-GB","potentialAction":[{"@type":"ReadAction","target":["https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/abstract230\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/"},{"@type":"ListItem","position":2,"name":"Programme","item":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/programme\/"},{"@type":"ListItem","position":3,"name":"Abstract 230"}]},{"@type":"WebSite","@id":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/#website","url":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/","name":"WWRP\/WCRP S2S Summit 2023","description":"Advancing Sub-seasonal to Seasonal Predictions and their Applications","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-GB"}]}},"_links":{"self":[{"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/pages\/1178","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/users\/145"}],"replies":[{"embeddable":true,"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/comments?post=1178"}],"version-history":[{"count":2,"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/pages\/1178\/revisions"}],"predecessor-version":[{"id":1199,"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/pages\/1178\/revisions\/1199"}],"up":[{"embeddable":true,"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/pages\/528"}],"wp:attachment":[{"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/media?parent=1178"}],"wp:term":[{"taxonomy":"author","embeddable":true,"href":"https:\/\/research.reading.ac.uk\/s2s-summit2023\/wp-json\/wp\/v2\/coauthors?post=1178"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}