{"id":36923,"date":"2020-05-30T18:56:25","date_gmt":"2020-05-30T18:56:25","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=36923"},"modified":"2020-06-03T14:41:36","modified_gmt":"2020-06-03T14:41:36","slug":"when-is-an-abi-hot-bright-spot-not-a-fire","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/36923","title":{"rendered":"When is an ABI hot (bright) spot not a fire?"},"content":{"rendered":"\r\n<p>An ABI hot (bright) spot is not a fire when it&#8217;s a fleet of solar farms. For example, recall the <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/33504\">CIMSS Satellite Blog entry<\/a> regarding solar farms in California.\u00a0<\/p>\r\n<div style=\"width: 650px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2020\/05\/GLINT_loop_2020151_183113_2020151_202613.mp4\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2020\/05\/GLINT_B2_2020151_193613_GOES-16_0001PANEL_FRAME00014.GIF\" alt=\"ABI band 2 visible\" width=\"640\" height=\"640\" \/><\/a><p class=\"wp-caption-text\">ABI band 2 visible animation on May 30, 2020 (mostly) in southeastern Minnesota. Click to play mp4.<\/p><\/div>\r\n<p>Note how some reflections are so bright that the ABI reports dark surrounding pixels. This is part of the remapping process from detector to pixel space.\u00a0<\/p>\r\n<p>&nbsp;<\/p>\r\n<div style=\"width: 650px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2020\/05\/MN_solar_farms_2020151_1831utcto2056utc.mp4\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2020\/05\/OR_ABI-L2-FDCC-M6_G16_s20201511936130_e20201511938503_c20201511939168.nc_MNsolar.png\" alt=\"9-panel\" width=\"640\" height=\"459\" \/><\/a><p class=\"wp-caption-text\">A multiple-spectral ABI comparison on May 30, 2020. The rows are: band 2, band 5, band 6 band 7, band 7 &#8211; 14 brightness temp, band 14 fire mask, band 7-14 radiance difference, band 7-14 radiance difference minus the rolling average<\/p><\/div>\r\n<p>From left to right, top to bottom the panels are:<br \/>1) ABI <strong>band 2<\/strong> reflectance, dynamically scaled to enhance contrast (will appear to flicker)<br \/>2) ABI <strong>band 5<\/strong> reflectance, dynamically scaled to enhance contrast (will appear to flicker)<br \/>3) ABI <strong>band 6<\/strong> reflectance, dynamically scaled to enhance contrast (will appear to flicker)<br \/>4) ABI <strong>band 7<\/strong> brightness temperature, dynamically scaled to enhance contrast (will appear to flicker)<br \/>5) ABI <strong>band 7 minus band 14<\/strong> brightness temperature. Red indicates positive values (extra thermal energy due to the sun and fires, if present), dynamically scaled to enhance contrast (will appear to flicker)<br \/>6) ABI <strong>band 14<\/strong> brightness temperature, dynamically scaled to enhance contrast (will appear to flicker)<br \/>7) ABI Fire Detection and Characterization Algorithm (FDCA, aka WFABBA)<strong> fire detection metadata mask<\/strong>.\u00a0 Fires are red, orange, magenta, and shades of blue indicating different confidence levels.\u00a0 Green indicates fire-free land, shades of gray indicate clouds, dark\u00a0 blue indicates water.<br \/>8) Radiance <strong>difference of band 7 minus band 14<\/strong> radiance in band 7 space.\u00a0 Red indicates positive values (extra thermal energy due to the sun and fires, if present), dynamically scaled to enhance contrast (will appear to flicker)<br \/>9) Radiance <strong>difference of band 7 minus band 14 radiance in band 7 space minus a rolling average<\/strong> of the 5 prior frames, to highlight changes. Red indicates positive values (extra thermal energy due to the sun and fires, if present), dynamically scaled to enhance contrast (will appear to flicker).<br \/><br \/>Aside from the <a href=\"https:\/\/www.google.com\/search?rlz=1C1CHBF_enUS874US874&amp;q=solar+farms+in+minnesota&amp;npsic=0&amp;rflfq=1&amp;rlha=0&amp;rllag=45233261,-93053072,30145&amp;tbm=lcl&amp;ved=2ahUKEwjahMHl7-XpAhUEba0KHdqXBrMQtgN6BAgLEAQ&amp;tbs=lrf:!1m4!1u3!2m2!3m1!1e1!2m1!1e3!3sIAE,lf:1,lf_ui:2&amp;rldoc=1#rlfi=hd:;si:;mv:[[45.26641092884788,-89.82971204843749],[43.55574445927599,-94.59777845468749],null,[44.417333065253885,-92.21374525156249],8]\">solar farms<\/a>, water clouds show up in the difference panels due to their reflection of shortwave radiation.\u00a0<\/p>\r\n<p>H\/T to <a href=\"https:\/\/twitter.com\/geofire\">Chris Schmidt<\/a> for the 9-panel ABI imagery.\u00a0 More about <a href=\"https:\/\/www.star.nesdis.noaa.gov\/goesr\/\">quantitative ABI products<\/a>, including fire detection.\u00a0<\/p>\r\n<p>The original <a href=\"https:\/\/twitter.com\/NWSLaCrosse\/status\/1266852686579683329\">tweet<\/a> from the <a href=\"https:\/\/twitter.com\/NWSLaCrosse\">La Crosse WFO<\/a>: &#8220;We saw some awfully bright looking &#8220;clouds&#8221; showing up via satellite in southeast Minnesota earlier this afternoon. Well after some investigation, we were able to determine they were actually solar panel arrays that the sun was hitting just right!&#8221;<\/p>\r\n<div style=\"width: 690px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2020\/05\/mn_awips_farms.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2020\/05\/mn_awips_farms.jpg\" alt=\"NWS tweet\" width=\"680\" height=\"510\" \/><\/a><p class=\"wp-caption-text\">Solar farms and GOES-16 ABI visible imagery from the La Crosse NWS WFO.<\/p><\/div>\r\n","protected":false},"excerpt":{"rendered":"<p>An ABI hot (bright) spot is not a fire when it&#8217;s a fleet of solar farms. For example, recall the CIMSS Satellite Blog entry regarding solar farms in California.\u00a0 Note how some reflections are so bright that the ABI reports dark surrounding pixels. This is part of the remapping process from detector to pixel space.\u00a0 [&hellip;]<\/p>\n","protected":false},"author":21,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[6,10,74,39],"tags":[],"class_list":["post-36923","post","type-post","status-publish","format-standard","hentry","category-fire-detection","category-general-interpretation","category-goes-16","category-training"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/36923","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\/21"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=36923"}],"version-history":[{"count":11,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/36923\/revisions"}],"predecessor-version":[{"id":36992,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/36923\/revisions\/36992"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=36923"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=36923"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=36923"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}