{"id":2704,"date":"2009-06-11T18:50:04","date_gmt":"2009-06-11T18:50:04","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=2704"},"modified":"2010-05-20T20:20:42","modified_gmt":"2010-05-20T20:20:42","slug":"denali-mount-mckinley-erupts","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/2704","title":{"rendered":"Denali (“Mt. McKinley”) erupts!"},"content":{"rendered":"
\"GOES-11<\/a>

GOES-11 visible images<\/p><\/div>\n

Well, not really — but a very interesting cloud plume formed yesterday and streamed off the 20,318-ft (6194-m) summit of Denali (“Mt. McKinley”) in southern Alaska on 10 June 2009<\/strong>, which almost had the\u00c2\u00a0 appearance of a volcanic eruption plume. GOES-11 visible images (above)<\/strong><\/em> showed this thin cloud plume spreading out as it curved to the southeast and then to the south, eventually moving over Anchorage and then the Kenai Peninsula.<\/p>\n

A 1-km resolution NOAA-18 AVHRR 10.8 \u00c2\u00b5m IR image (below)<\/strong><\/em> indicated that IR brightness temperatures were quite warm for such a high-altitude cirrus plume, barely reaching the -15 to -20\u00c2\u00ba C range. Due to the thin nature of this cloud plume, a significant amount of radiation from the warmer ground surfaces below was bleeding upward through the thin cloud layer and reaching the satellite detectors.<\/p>\n

\"NOAA-18<\/a>

NOAA-18 AVHRR 10.8 \u00c2\u00b5m IR image<\/p><\/div>\n

A false-color NOAA-18 Red\/Green\/Blue (RGB) image (below)<\/strong><\/em> showed the “transparent” nature of the cloud plume, with snow cover features on the ground clearly recognizable beneath the cloud.<\/p>\n

\"NOAA-18<\/a>

NOAA-18 AVHRR false color RGB image<\/p><\/div>\n

Tracking the location of the leading edge of the thin cloud plume feature was difficult using single-channel satellite imagery, which underscores the importance of using multi-spectral satellite products such as the 10.8 – 12.0 \u00c2\u00b5m IR difference\u00c2\u00a0 (below)<\/strong><\/em> to correctly analyze the cloud location. Areas where the IR difference product reached +7 to +10 K (cyan colors)<\/em> corresponded to the thicker portions of the cloud plume.<\/p>\n

\"NOAA-18<\/a>

NOAA-18 IR difference product (10.8 - 12.0 \u00c2\u00b5m, channel 04 - 05)<\/p><\/div>\n

The cloud plume was curving to the southeast and then to the south due to the presence of a ridge of high pressure aloft over southern Alaska, as seen on an AWIPS image of the GOES-11 IR channel with an overlay of the GFS model 500 hPa winds (below)<\/strong><\/em>.<\/p>\n

\"GOES-11<\/a>

GOES-11 10.7 \u00c2\u00b5m IR image + GSF 500 hPa winds<\/p><\/div>\n

A tip of the hat to Emily Niebuhr, UW-Madison \/ AOS graduate student, who is currently up in Alaska and brought this to our attention!<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Well, not really — but a very interesting cloud plume formed yesterday and streamed off the 20,318-ft (6194-m) summit of Denali (“Mt. McKinley”) in southern Alaska on 10 June 2009, which almost had the\u00c2\u00a0 appearance of a volcanic eruption plume. GOES-11 visible images (above) showed this thin cloud plume spreading out as it curved to […]<\/p>\n","protected":false},"author":18,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37,22,18,26,45],"tags":[],"class_list":["post-2704","post","type-post","status-publish","format-standard","hentry","category-arctic","category-avhrr","category-goes-11","category-poes","category-redgreenblue-rgb-images"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/2704","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/users\/18"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=2704"}],"version-history":[{"count":15,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/2704\/revisions"}],"predecessor-version":[{"id":5733,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/2704\/revisions\/5733"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=2704"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=2704"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=2704"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}