{"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":"
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<\/a>The “iconic” 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<\/a>). Elsewhere, though, the pattern of surface warming is more complex – trends are smaller, and while more are positive than negative they are generally not significant – see this map<\/a>. Contrary to what you might have heard, this is in general agreement with model predictions<\/a>.<\/p>\n

But meanwhile, there is a record for the upper atmosphere derived from radiosondes, which we have been working on – 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

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’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

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

[Quick addendum: the paper itself is available via this<\/a>.]<\/p>\n\n<\/div> ","protected":false},"excerpt":{"rendered":"

The “iconic” 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 – trends are smaller, and while more are positive than negative they are […]<\/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":["post-283","post","type-post","status-publish","format-standard","category-arctic-and-antarctic","category-climate-science","category-instrumental-record","entry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t