{"id":866,"date":"2008-08-20T23:59:30","date_gmt":"2008-08-20T23:59:30","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=866"},"modified":"2008-08-28T16:05:52","modified_gmt":"2008-08-28T16:05:52","slug":"satellite-products-for-interrogating-low-clouds","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/866","title":{"rendered":"Satellite products for interrogating low clouds"},"content":{"rendered":"
\"MODIS<\/a>

AWIPS images of the MODIS + GOES-12 "IR window" channel (Animated GIF)<\/p><\/div>\n

Areas of low cloudiness (such as stratus and\/or fog)<\/em> at night can be important aviation hazards, but they are sometimes difficult to identify simply by examining standard IR imagery. A comparison of 1-km resolution MODIS 11.0 \u00c2\u00b5m and 4-km resolution GOES-12 10.7 \u00c2\u00b5m “IR window” images (above)<\/strong><\/em> does not give the sense that there was widespread fog and stratus clouds in place over much of eastern Colorado during the pre-dawn hours on 20 August 2008<\/strong><\/a>. Even with a color enhancement that highlights the warmer range of IR brightness temperatures (below)<\/strong>,<\/em> the edges of the low cloud feature are difficult to pick out unambiguously.<\/p>\n

\"MODIS<\/a>

AWIPS images of the MODIS + GOES-12 "IR window" channel (Animated GIF)<\/p><\/div>\n

There are a variety of satellite products available in AWIPS that can be used to better identify and characterize areas of low cloudiness and fog. In this case, the 1-km resolution MODIS fog\/stratus product (below)<\/strong><\/em> showed very good details about the edges and structure of the area of low clouds and fog, with the corresponding\u00c2\u00a0 4-km resolution MODIS Cloud Top Temperature and Cloud Phase products\u00c2\u00a0 indicating that the cloud tops over eastern Colorado were composed of water droplets (blue enhancement)<\/em> with cloud top temperatures around +5\u00c2\u00ba C (red enhancement)<\/em>. However, note that there was another separate area of supercooled cloud tops farther to the east (located over western Kansas),<\/em> where the Cloud Top Temperatures were below freezing (yellow enhancement)<\/em> while the Cloud Phase product still indicated water droplet clouds (blue enhancement)<\/em> — regions such as this might pose a higher risk for aircraft icing.<\/p>\n

\"MODIS<\/a>

AWIPS images of the MODIS fog\/stratus + cloud top temperature + cloud phase products (Animated GIF)<\/p><\/div>\n

Using the GOES-12 satellite, one can examine the 4-km resolution fog\/stratus product (below)<\/strong>,<\/em> and also utilize the 4-km resolution Low Cloud Base product along with the 10-km resolution sounder-derived Effective Cloud Amount and Cloud Top Height products to gain additional information about the cloud base height, cloud coverage, and cloud top height.<\/p>\n

\"GOES-12<\/a>

AWIPS images of the GOES-12 fog\/stratus + low cloud base + effective cloud amount + cloud top height products (Animated GIF)<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

Areas of low cloudiness (such as stratus and\/or fog) at night can be important aviation hazards, but they are sometimes difficult to identify simply by examining standard IR imagery. A comparison of 1-km resolution MODIS 11.0 \u00c2\u00b5m and 4-km resolution GOES-12 10.7 \u00c2\u00b5m “IR window” images (above) does not give the sense that there was […]<\/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":[21,13,15,19,12],"tags":[],"class_list":["post-866","post","type-post","status-publish","format-standard","hentry","category-aviation","category-fog-detection","category-goes-sounder","category-goes-12","category-modis"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/866","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=866"}],"version-history":[{"count":9,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/866\/revisions"}],"predecessor-version":[{"id":871,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/866\/revisions\/871"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=866"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=866"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=866"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}