{"id":2512,"date":"2009-05-07T20:24:40","date_gmt":"2009-05-07T20:24:40","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=2512"},"modified":"2009-05-08T20:20:01","modified_gmt":"2009-05-08T20:20:01","slug":"advection-fog-over-lake-michigan-2","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/2512","title":{"rendered":"Advection fog over Lake Michigan"},"content":{"rendered":"<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/090507_g12_vis_anim.gif\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" title=\"GOES-12 visible images\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/090507_g12_vis_anim.gif\" alt=\"GOES-12 visible images\" width=\"480\" height=\"359\" \/><\/a><p class=\"wp-caption-text\">GOES-12 visible images<\/p><\/div>\n<p>GOES-12 visible channel images <em><strong>(above)<\/strong><\/em> showed advection fog that developed over Lake Michigan during the day on <a title=\"07 May 2009 daily weather map\" href=\"http:\/\/www.hpc.ncep.noaa.gov\/dailywxmap\/index_20090507.html\" target=\"_blank\"><strong>07 May 2009<\/strong><\/a>. As pointed out on the <a title=\"US Air Quality (Smog Blog)\" href=\"http:\/\/alg.umbc.edu\/usaq\/archives\/003334.html\" target=\"_blank\"><strong>US Air Quality (aka The Smog Blog)<\/strong><\/a> site,\u00c2\u00a0 this fog &#8220;fooled&#8221; the MODIS Aerosol Optical Depth (AOD) algorithm, causing a false signal of very high AOD over Lake Michigan. Also note the appearance of &#8220;shock waves&#8221; in the fog bank as it encountered obstructions to the southwesterly boundary layer flow in two areas: (1) along the western coastline of Lower Michigan <strong><em>(<a title=\"MODIS true color image\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/090507_modis_truecolor_1.jpg\" target=\"_blank\">250-m resolution MODIS true color image<\/a>),<\/em><\/strong> and (2)\u00c2\u00a0 some of the larger islands in the northern portion of Lake Michigan <strong><em>(<a title=\"MODIS true color image\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/090507_modis_truecolor_2.jpg\" target=\"_blank\">250-m resolution MODIS true color image<\/a>)<\/em><\/strong>.<\/p>\n<p>This fog formed as warm and relatively humid air <em>(with dew points in the middle 50s F)<\/em> moved across the cold waters of Lake Michigan. An AWIPS image of the MODIS Sea Surface Temperature (SST) product <em><strong>(below)<\/strong><\/em> indicated that that mid-lake SST values were still in the 37-39\u00c2\u00ba F range &#8212; and\u00c2\u00a0 this was confirmed by the water temperature values of 37\u00c2\u00ba F and 38\u00c2\u00ba F reported by buoys 45002 and 45007, respectively.<\/p>\n<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/MODIS_SST_20090507_1629.png\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" title=\"MODIS Sea Surface Temperature product\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/MODIS_SST_20090507_1629.png\" alt=\"MODIS Sea Surface Temperature product\" width=\"480\" height=\"459\" \/><\/a><p class=\"wp-caption-text\">MODIS Sea Surface Temperature product<\/p><\/div>\n<p>The western portion of the advection fog feature was quite thin, so the fog edge was difficult to pick out on the MODIS 11.0 \u00c2\u00b5m &#8220;IR window&#8221; imagery <em><strong>(below)<\/strong><\/em>. However, the fog boundaries were quite apparent on the 3.7 \u00c2\u00b5m &#8220;shortwave IR&#8221; imagery, due to the reflection of solar radiation off the top of the water droplet fog feature <em><strong>(which made the fog appear darker\/warmer).<\/strong><\/em><\/p>\n<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/090507_modis_vis_ir_anim.gif\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" title=\"MODIS visible, 11.0 \u00c2\u00b5m IR window, 3.7 \u00c2\u00b5m shortwave IR images\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/090507_modis_vis_ir_anim.gif\" alt=\"MODIS visible, 11.0 \u00c2\u00b5m IR window, 3.7 \u00c2\u00b5m shortwave IR images\" width=\"480\" height=\"460\" \/><\/a><p class=\"wp-caption-text\">MODIS visible, 11.0 \u00c2\u00b5m IR window, 3.7 \u00c2\u00b5m shortwave IR images<\/p><\/div>\n<p>The GOES sounder Cloud Top Height product <em><strong>(below)<\/strong><\/em> indicated that the tops of the fog feature over the southern half of Lake Michigan were generally around 2580 feet <em>(darker brown color enhancement)<\/em>.<\/p>\n<div style=\"width: 489px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/NA_GOES_Sounder_DPI_CTH_20090507_1700.png\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" title=\"GOES-12 sounder Cloud Top Height product\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/05\/NA_GOES_Sounder_DPI_CTH_20090507_1700.png\" alt=\"GOES-12 sounder Cloud Top Height product\" width=\"479\" height=\"458\" \/><\/a><p class=\"wp-caption-text\">GOES-12 sounder Cloud Top Height product<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"<p>GOES-12 visible channel images (above) showed advection fog that developed over Lake Michigan during the day on 07 May 2009. As pointed out on the US Air Quality (aka The Smog Blog) site,\u00c2\u00a0 this fog &#8220;fooled&#8221; the MODIS Aerosol Optical Depth (AOD) algorithm, causing a false signal of very high AOD over Lake Michigan. Also [&hellip;]<\/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":[13,15,19,12],"tags":[],"class_list":["post-2512","post","type-post","status-publish","format-standard","hentry","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\/2512","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=2512"}],"version-history":[{"count":15,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/2512\/revisions"}],"predecessor-version":[{"id":2516,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/2512\/revisions\/2516"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=2512"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=2512"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=2512"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}