{"id":17092,"date":"2014-10-28T23:58:19","date_gmt":"2014-10-28T23:58:19","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=17092"},"modified":"2014-10-31T22:49:39","modified_gmt":"2014-10-31T22:49:39","slug":"airborne-glacial-silt-from-the-copper-river-valley-in-alaska","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/17092","title":{"rendered":"Airborne glacial silt from the Copper River Valley in Alaska"},"content":{"rendered":"
\"GOES-15<\/a>

GOES-15 0.63 \u00b5m visible channel images (click to play animation)<\/p><\/div>\n

McIDAS images of GOES-15 0.63 \u00b5m visible channel data (above; click image to play animation)<\/strong><\/em> showed the hazy signature of airborne glacial silt drifting southward out of the Copper River valley and over the adjacent waters of the Gulf of Alaska on 28 October 2014. The strong winds lofting the silt were very localized to the Copper River valley itself, with cold dense arctic air from further inland (air temperatures were 8 to 10\u00ba F at Gulkana, PAGV) accelerating through narrow mountain passes — note how winds at nearby Cordova (PACV) were generally calm during much of the period. As the western edge of the airborne silt reached Middleton Island (PAMD), the surface visibility dropped as low as 5 miles.<\/p>\n

AWIPS II images of Suomi NPP VIIRS data provided a better view of the aerial coverage of the glacial silt: a comparison of VIIRS 0.64 \u00b5m visible channel and 1.61 \u00b5m near-IR “snow\/ice channel” images (below)<\/strong><\/em> showed that the 1.61 \u00b5m image offered better contrast to help locate the edges of the feature. This 1.61 \u00b5m channel imagery will be available from the Advanced Baseline Imager (ABI<\/strong><\/a>) on GOES-R<\/strong><\/a>.<\/p>\n

\"Suomi<\/a>

Suomi NPP VIIRS 0.64 \u00b5m visible channel and 1.61 \u00b5m near-IR “snow\/ice channel” images<\/p><\/div>\n

Two consecutive VIIRS 1.61 \u00b5m images (below)<\/strong><\/em> revealed the changes in aerosol coverage between 21:43 UTC and 23:22 UTC.<\/p>\n

\"Suomi<\/a>

Suomi NPP VIIRS 1.61 \u00b5m near-IR “snow\/ice channel” images<\/p><\/div>\n

The more dense portion of the airborne glacial silt particle feature exhibited a slightly warmer (darker gray)<\/em> appearance on VIIRS 3.74 \u00b5m shortwave IR images, due to efficient reflection of incoming solar radiation.<\/p>\n

\"Suomi<\/a>

Suomi NPP VIIRS 3.74 \u00b5m shortwave IR images<\/p><\/div>\n

A VIIRS true-color Red\/Green\/Blue (RGB) image from the SSEC RealEarth<\/strong><\/a> site (below)<\/strong><\/em> offered a good view of the coverage of the glacial silt at 21:45 UTC.<\/p>\n

\"Suomi<\/a>

Suomi NPP VIIRS true-color image<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

McIDAS images of GOES-15 0.63 \u00b5m visible channel data (above; click image to play animation) showed the hazy signature of airborne glacial silt drifting southward out of the Copper River valley and over the adjacent waters of the Gulf of Alaska on 28 October 2014. The strong winds lofting the silt were very localized to […]<\/p>\n","protected":false},"author":18,"featured_media":17096,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[7,43,34,53,45,49,48],"tags":[],"class_list":["post-17092","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-air-quality","category-goes-15","category-goes-r","category-real-earth","category-redgreenblue-rgb-images","category-suomi_npp","category-viirs"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/17092","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=17092"}],"version-history":[{"count":6,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/17092\/revisions"}],"predecessor-version":[{"id":17102,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/17092\/revisions\/17102"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/17096"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=17092"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=17092"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=17092"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}