{"id":10341,"date":"2012-05-15T20:10:25","date_gmt":"2012-05-15T20:10:25","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=10341"},"modified":"2014-11-17T22:14:03","modified_gmt":"2014-11-17T22:14:03","slug":"goes-13-band-co-registration","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/10341","title":{"rendered":"GOES-13 Imager Band Co-Registration"},"content":{"rendered":"<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/Reg_11-3.9_Sat_20120514_1015.png\"><img loading=\"lazy\" decoding=\"async\" title=\"GOES-13 enhanced Fog Product (10.7 \u00b5m- 3.9 \u00b5m)\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/Reg_11-3.9_Sat_20120514_1015.png\" alt=\"GOES-13 enhanced Fog Product (10.7 \u00b5m - 3.9 \u00b5m)\" width=\"480\" height=\"249\" \/><\/a><p class=\"wp-caption-text\">GOES-13 enhanced Fog Product (10.7 \u00b5m - 3.9 \u00b5m)<\/p><\/div>\n<p>On the morning of May 14th, a clear morning, the GOES-13 Legacy &#8220;Fog Product&#8221; that exploits the brightness temperature differences observed by the GOES Imager at 3.9 \u00b5m and 10.7 \u00b5m, which differences arise because of wavelength-dependent emissivity differences in water clouds, showed fog first on the eastern shores of Lakes Huron and Michigan (at <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/Reg_11-3.9_Sat_20120514_1015.png\">1015 UTC<\/a>), and then on the western shores of Lakes Huron and Michigan (at <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/Reg_11-3.9_Sat_20120514_1401.png\">1401 UTC<\/a>, and afterwards). These returns occurred despite <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/Reg_Vis_Sat_20120514_1401.png\">clear skies<\/a>.<\/p>\n<p>A similar effect occurred on the morning of May 15th. The image at <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/Reg_11-3.9_Sat_20120515_1015.png\">1015 UTC showed fog<\/a> along the eastern side of the Lakes, and the image at <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/Reg_11-3.9_Sat_20120515_1255.png\">1255 UTC<\/a> showed fog along the western side of the Lakes. (Note that more widespread mid-level clouds reduced the signal on this day). A POES Fog Product image from 1020 UTC on May 15th (<a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/POES__11-3.7_Sat_20120515_1020.png\">link<\/a>) did not show the fog signal along the shoreline.<\/p>\n<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/GOES13_bandloop_1255UTC_15May2012.gif\"><img loading=\"lazy\" decoding=\"async\" class=\" \" title=\"GOES-13 10.7 \u00b5m and 3.9 \u00b5m channel images (click image to toggle between images)\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/GOES13_10.7_1255UTC_15MAY2012.GIF\" alt=\"GOES-13 10.7 \u00b5m and 3.9 \u00b5m channel images (click image to toggle between images)\" width=\"480\" height=\"348\" \/><\/a><p class=\"wp-caption-text\">GOES-13 10.7 \u00b5m and 3.9 \u00b5m channel images (click image to toggle between images)<\/p><\/div>\n<p>The image toggle above shows highly magnified imagery over Lake Michigan at 1255 UTC on May 15 2012. There is an apparent 1-pixel shift between the 3.9 \u00b5m and the 10.7 \u00b5m imagery. If the start element of the image is shifted by 1 infrared pixel, then the <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2012\/05\/GOES13_bandloopfix_1255UTC_15MAY2012.gif\">toggle between the two images<\/a> contains no shift. The legacy &#8216;Fog Product&#8217; is therefore diagnosing fog because the 3.9 \u00b5m pixel is over water (cold) and the 10.7 \u00b5m pixel is over land (warm). When the 1-pixel shift is rectified, both pixels are either over water, or both over land.<\/p>\n<p>Scientists at NESDIS are working to find the source of this difference.<\/p>\n<p>===================================================================<\/p>\n<p>Update, 17 November 2014<\/p>\n<p>A software fix has been identified and tested.   <a href=\"http:\/\/fusedfog.ssec.wisc.edu\/?p=910\">Link<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>On the morning of May 14th, a clear morning, the GOES-13 Legacy &#8220;Fog Product&#8221; that exploits the brightness temperature differences observed by the GOES Imager at 3.9 \u00b5m and 10.7 \u00b5m, which differences arise because of wavelength-dependent emissivity differences in water clouds, showed fog first on the eastern shores of Lakes Huron and Michigan (at [&hellip;]<\/p>\n","protected":false},"author":19,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[50,10,11],"tags":[],"class_list":["post-10341","post","type-post","status-publish","format-standard","hentry","category-calibration","category-general-interpretation","category-goes-13"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/10341","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\/19"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=10341"}],"version-history":[{"count":20,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/10341\/revisions"}],"predecessor-version":[{"id":17195,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/10341\/revisions\/17195"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=10341"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=10341"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=10341"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}