{"id":49886,"date":"2023-01-19T20:27:00","date_gmt":"2023-01-19T20:27:00","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=49886"},"modified":"2023-01-23T16:57:06","modified_gmt":"2023-01-23T16:57:06","slug":"a-small-fire-on-the-texas-gulf-coast","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/49886","title":{"rendered":"A small fire on the Texas Gulf Coast (and Gamma!)"},"content":{"rendered":"\n<figure class=\"wp-block-video\"><video height=\"734\" style=\"aspect-ratio: 1288 \/ 734;\" width=\"1288\" controls loop src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/goeseast_abi_radc_true_color_night_s20230119162617_e20230119190117_f32.mp4\"><\/video><figcaption class=\"wp-element-caption\">GOES-16 True-Color imagery from the CSPP Geosphere site, 1626 &#8211; 1901 UTC on 19 January 2023<\/figcaption><\/figure>\n\n\n\n<p>True color imagery from the <a href=\"https:\/\/geosphere.ssec.wisc.edu\/#coordinate:0,0;\">CSPP Geosphere<\/a> site, shown above (click <a href=\"https:\/\/geosphere.ssec.wisc.edu\/#playing:true;coordinate:-1763184,3047680;zoom:7.2;coverage:radc;map_borders:off;num_frames:32;start_time:2023-01-19T16:26:00Z;timeframe:Start%20Time;\">here<\/a> for a direct link to the animation), depicts the sudden appearance and equally sudden ending of a small fire on the Texas Gulf Coast in Jefferson County, east-northeast of Houston.<\/p>\n\n\n\n<p>The <a href=\"https:\/\/rammb.cira.colostate.edu\/training\/visit\/quick_guides\/Fire_Temperature_RGB.pdf\">Fire Temperature RGB<\/a> also shows the quick development (and cessation) of the fire; this RGB is a good situational awareness tool, as it shows an obvious color change (related to the increase in emissions of shortwave radation) when the fire initiates.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/FireRGB_Texas-20230119_1626_1901anim.gif\"><img loading=\"lazy\" decoding=\"async\" width=\"1524\" height=\"969\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/FireRGB_Texas-20230119_1626_1901anim.gif\" alt=\"\" class=\"wp-image-49888\"\/><\/a><figcaption class=\"wp-element-caption\">Fire Temperature RGB, 1626-1901 UTC on 29 January 2023 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n<p>GOES-R has derived products that quantify aspects of the detected fire, as shown in the four-panel image below from 1731 UTC, near the time when the fire was most intense. Note the contributions of the red and green components of the RGB, from the 3.9 \u00b5m and 2.25 \u00b5m channels, respectively, on GOES-16, have maximized in the center pixel, so that pixel is yellow in the RGB (red + green in an RGB yields yellow);  had the 1.61 \u00b5m emissions been stronger (that is, had the fire been hotter), the pixel would look whiter.  The Fire Products (Area, Temperature, Power) are most useful as data assimilated into models that might simulate the evolution of the fire, or the distribution of smoke.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"695\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/G16Products_1731_19Januar2023-1024x695.png\" alt=\"\" class=\"wp-image-49890\" srcset=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/G16Products_1731_19Januar2023-1024x695.png 1024w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/G16Products_1731_19Januar2023-300x204.png 300w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/G16Products_1731_19Januar2023-768x521.png 768w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/G16Products_1731_19Januar2023.png 1533w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Clockwise from upper left: Fire Temperature RGB,  GOES-16 Fire Area, GOES-16 Fire Temperature, GOES-16 Fire Power, all at 1731 UTC on 19 January 2023 (Click to enlarge) <\/figcaption><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>The Fire Temperature RGB is one of the few RGB products in AWIPS that has a gamma adjustment.  A gamma adjustment alters how the ranges of input values (in this case, 3.9 \u00b5m brightness temperatures) are displayed.  For the Fire Temperature RGB, the warmest parts of the 3.9 \u00b5m brightness temperatures occupy proportionally more of the display space in the RGB, and the cooler parts of the RGB (where fire is unlikely, yet information is still needed!) occupy less.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/GammaPlotExplanation.png\" alt=\"\" class=\"wp-image-49891\" width=\"360\" height=\"360\" srcset=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/GammaPlotExplanation.png 720w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/GammaPlotExplanation-300x300.png 300w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/GammaPlotExplanation-150x150.png 150w\" sizes=\"auto, (max-width: 360px) 100vw, 360px\" \/><\/figure>\n\n\n\n<p>AWIPS allows a gamma adjustment to be altered (using the &#8216;Composite Options&#8217; window).  The toggle below compares the default RGB to one in which the Band 7 Gamma adjustment has been changed to Gamma = 1, resulting in a very red image (because cooler brightness temperatures &#8212; that are not that relevant to the detection of fire &#8212; are more emphasized).<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/FireRGB_TexasGamma-20230119_1731Labeltoggle.gif\"><img loading=\"lazy\" decoding=\"async\" width=\"1524\" height=\"969\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/01\/FireRGB_TexasGamma-20230119_1731Labeltoggle.gif\" alt=\"\" class=\"wp-image-49926\"\/><\/a><figcaption class=\"wp-element-caption\">Fire Temperature RGB with different Gammas (default, and Gamma=1) in the &#8216;red&#8217; beam, 1731 UTC on 19 January 2023 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>Note:  AWIPS users might note that the default Gamma of the RGB is 2.5, but the Quick Guide shows the Gamma to be 0.4 (that is, 1\/2.5)!  This may be a source of confusion.  <a href=\"https:\/\/www.eumetsat.int\/media\/43014\">This website<\/a> shows a Gamma modification of 1\/Gamma &#8212; and if Gamma is 0.4, that exponent becomes 2.5, which is what AWIPS shows.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>True color imagery from the CSPP Geosphere site, shown above (click here for a direct link to the animation), depicts the sudden appearance and equally sudden ending of a small fire on the Texas Gulf Coast in Jefferson County, east-northeast of Houston. The Fire Temperature RGB also shows the quick development (and cessation) of the [&hellip;]<\/p>\n","protected":false},"author":19,"featured_media":49890,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[6,74],"tags":[],"class_list":["post-49886","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-fire-detection","category-goes-16"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/49886","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=49886"}],"version-history":[{"count":5,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/49886\/revisions"}],"predecessor-version":[{"id":49937,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/49886\/revisions\/49937"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/49890"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=49886"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=49886"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=49886"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}