{"id":283,"date":"2006-03-31T15:17:41","date_gmt":"2006-03-31T19:17:41","guid":{"rendered":"\/?p=283"},"modified":"2007-08-24T09:26:48","modified_gmt":"2007-08-24T14:26:48","slug":"significant-warming-of-the-antarctic-winter-troposphere","status":"publish","type":"post","link":"https:\/\/www.realclimate.org\/index.php\/archives\/2006\/03\/significant-warming-of-the-antarctic-winter-troposphere\/","title":{"rendered":"Significant Warming of the Antarctic Winter Troposphere"},"content":{"rendered":"<div class=\"kcite-section\" kcite-section-id=\"283\">\n<p><a href=http:\/\/www.antarctica.ac.uk\/met\/wmc\/gjma-500hpa-map.png><img src=http:\/\/www.antarctica.ac.uk\/met\/wmc\/gjma-500hpa-map.png align=right width=250 height=250\/><\/a>The &#8220;iconic&#8221; Antarctic temperature trends are the large warming seen on the Antarctic Peninsula, which has had various repercussions including the collapse of several ice shelves (some documented in a <a href=http:\/\/www.realclimate.org\/index.php?p=146>previous post<\/a>). Elsewhere, though, the pattern of surface warming is more complex &#8211; trends are smaller, and while more are positive than negative they are generally not significant &#8211; see <a href=http:\/\/www.nerc-bas.ac.uk\/public\/icd\/gjma\/trends2004.col.pdf>this map<\/a>. Contrary to what you might have heard, this is in <a href=http:\/\/www.realclimate.org\/index.php?p=234>general agreement with model predictions<\/a>.<\/p>\n<p>But meanwhile, there is a record for the upper atmosphere derived from radiosondes, which we have been working on &#8211; finding old datasets and digitising them to fill in gaps. What this shows is that around East Antarctica there is a general warming of the troposphere, greatest at around mid-height (at 600 hPa) at 0.7 \u00baC\/decade over the last 30+ years.<\/p>\n<p>In itself, this is an interesting observation. The obvious question is, what does it mean? Is this natural variability; is it a response to global warming, or to changes in ozone; or something else? Ozone is unlikely, because this is winter (which conveniently means that the radiosonde temperature corrections, often a source of potential trouble, are not a problem). Two ways of trying to interpret the record are to see what GCMs run for the same period show; or to look at the re-analyses (essentially, the archived outputs from the weather-prediction models). The latter, of course, incorporate many of the radiosonde observations that we are using, and so don&#8217;t count as independant. Despite this, the ECMWF re-analyses show *greater* trends than we see in the observations; and a maximum trend over West Antarctica (which has no radisonde stations to allow us to verify this). A climate model (HadCM3, with an ensemble of four members) shows similar patterns to the observations, but this time too little warming; and a good deal of variation between the ensemble members. So neither of these is helps much with the interpretation.<\/p>\n<p>So we are currently left with an open question; hopefully, this will stimulate us and other researchers to explain it in the future.<\/p>\n<p>[Quick addendum: the paper itself is available <a href=http:\/\/scienceblogs.com\/stoat\/2006\/03\/science_significant_warming_of.php>via this<\/a>.]<\/p>\n<!-- kcite active, but no citations found -->\n<\/div> <!-- kcite-section 283 -->","protected":false},"excerpt":{"rendered":"<p>The &#8220;iconic&#8221; Antarctic temperature trends are the large warming seen on the Antarctic Peninsula, which has had various repercussions including the collapse of several ice shelves (some documented in a previous post). Elsewhere, though, the pattern of surface warming is more complex &#8211; trends are smaller, and while more are positive than negative they are [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[12,1,9],"tags":[],"class_list":{"0":"post-283","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-arctic-and-antarctic","7":"category-climate-science","8":"category-instrumental-record","9":"entry"},"aioseo_notices":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/posts\/283","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/comments?post=283"}],"version-history":[{"count":0,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/posts\/283\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/media?parent=283"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/categories?post=283"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/tags?post=283"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}