{"id":9912,"date":"2012-03-06T23:59:18","date_gmt":"2012-03-06T23:59:18","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=9912"},"modified":"2012-03-07T14:53:08","modified_gmt":"2012-03-07T14:53:08","slug":"ice-eddies-in-the-gulf-of-saint-lawrence","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/9912","title":{"rendered":"Ice eddies in the Gulf of Saint Lawrence"},"content":{"rendered":"

We received the following in an email from John Goff, lead forecaster at the Burlington, Vermont<\/a><\/strong> National Weather Service office:<\/p>\n

“Couldn’t help but notice the apparent large ice eddies up in the Gulf of Saint Lawrence this afternoon (3\/6) per the TERRA MODIS noon overpass (250m res). I thought that initially these were eddy\/small-scale cloud vortices we sometimes see up there, but upon looping the GOES visible imagery on my AWIPS workstation it’s fairly obvious these are not clouds, but ice structures.”<\/p><\/blockquote>\n

\"GOES-13<\/a>

GOES-13 0.63 \u00c2\u00b5m visible channel images (click image to play animation)<\/p><\/div>\n

Thanks John for the heads-up on this very interesting example! McIDAS images of 1-km resolution GOES-13 0.63 \u00c2\u00b5m visible channel data (above; click image to play animation)<\/em><\/strong> showed the development and motion of the ice eddies on 06 March 2012<\/strong>. Note how many of the ice floe structures began to move toward the northeast by the end of the day, due to increasing southwesterly surface winds across the region.<\/p>\n

A comparison of AWIPS images of 1-km resolution MODIS 0.65 \u00c2\u00b5m visible channel data and the corresponding MODIS false-color Red\/Green\/Blue (RGB) image (below)<\/em><\/strong> demonstrated the value of using RGB imagery to aid in the discrimination between snow\/ice (which appeared as varying shades of red in the false-color RGB image)<\/em> and supercooled water droplet clouds (which appeared as the brighter white to cyan features on the RGB image)<\/em>.<\/p>\n

\"MODIS<\/a>

MODIS 0.65 \u00c2\u00b5m visible channel image + MODIS false-color Red\/Green\/Blue (RGB) image<\/p><\/div>\n

An AWIPS image of the 1-km resolution POES AVHRR Sea Surface Temperature (SST) product at 18:55 UTC (below)<\/em><\/strong> indicated that SST values over the open waters were in the 30-31\u00c2\u00ba F range (blue color enhancement),<\/em> while the ice features exhibited colder values in the 23-25\u00c2\u00ba F range (violet color enhancement)<\/em>.<\/p>\n

\"POES<\/a>

POES AVHRR Sea Surface Temperature product<\/p><\/div>\n

Finally, a comparison of 250-meter resolution MODIS true color<\/a><\/strong> and false color Red\/Green\/Blue (RGB) images from the SSEC MODIS Today<\/a><\/strong> site (below)<\/em><\/strong> showed a closer view of the ice eddies, and again demonstrated the value of using various RGB image combinations to discriminate between snow\/ice (cyan in the false-color image)<\/em> and supercooled water droplet low cloud features (white on the true-color image)<\/em>.<\/p>\n

\"MODIS<\/a>

MODIS true-color and false-color Red\/Green\/Blue (RGB) images<\/p><\/div>\n

CIMSS participation in GOES-R Proving Ground<\/strong><\/a> activities includes making a variety of POES AVHRR<\/strong><\/a> and MODIS<\/a><\/strong> images and products available for National Weather Service forecast offices to add to their local AWIPS workstations. Currently there are 51 NWS offices<\/a><\/strong> receiving MODIS imagery and products from CIMSS.<\/p>\n","protected":false},"excerpt":{"rendered":"

We received the following in an email from John Goff, lead forecaster at the Burlington, Vermont National Weather Service office: “Couldn’t help but notice the apparent large ice eddies up in the Gulf of Saint Lawrence this afternoon (3\/6) per the TERRA MODIS noon overpass (250m res). I thought that initially these were eddy\/small-scale cloud […]<\/p>\n","protected":false},"author":18,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[22,11,34,12,26,45,5],"tags":[],"class_list":["post-9912","post","type-post","status-publish","format-standard","hentry","category-avhrr","category-goes-13","category-goes-r","category-modis","category-poes","category-redgreenblue-rgb-images","category-winter-weather"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/9912","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=9912"}],"version-history":[{"count":13,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/9912\/revisions"}],"predecessor-version":[{"id":9925,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/9912\/revisions\/9925"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=9912"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=9912"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=9912"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}