{"id":23337,"date":"2017-03-10T22:59:06","date_gmt":"2017-03-10T22:59:06","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=23337"},"modified":"2017-03-11T22:46:17","modified_gmt":"2017-03-11T22:46:17","slug":"multi-spectral-views-of-fire-with-goes-16-data","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/23337","title":{"rendered":"Multi-spectral views of smoke and fire with GOES-16 Data"},"content":{"rendered":"

\"GOES-16<\/a>

GOES-16 Infrared 3.9 \u00b5m images on 7 March 2017 [click to enlarge]<\/p><\/div>The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. <\/strong><\/p>\n

Tweets on Tuesday 7 March 2017 highlighted the fast-moving fires over the High Plains (that began burning on 6 March<\/a>), and they also highlighted different bands available from the GOES-16 ABI<\/a>. For example, this tweet<\/a> references the loop above, showing an animation of 3.9 \u00b5m temperatures; that shortwave infrared channel is used because it is more sensitive to hot temperatures than longer wavelength infrared channels. The Norman WFO also tweeted out imagery<\/a>, shown below, that included the 0.86 \u00b5m ‘Veggie’ band<\/a> and the 0.47 \u00b5m visible band<\/a>. Why use those two channels?<\/p>\n

\"GOES-16<\/a>

GOES-16 0.86 \u00b5m (near infrared) and 0.47 \u00b5m (visible) imagery from 07 March 2017 [click to enlarge]<\/p><\/div>The 0.47 \u00b5m imagery is observing a part of the visible electromagnetic spectrum where scattering is largest, so smoke plumes are more apparent at that wavelength than at 0.64 \u00b5m. For a very obvious event such as this one, this might not be as important, but for a modest fire event over Florida, shown next, it can be. The 0.86 \u00b5m imagery is useful because it very distinctly shows fire burn scars; that is, the contrast at 0.86 \u00b5m between vegetated soil and adjacent burned regions is greater than occurs at other visible wavelengths. That is shown in the toggle below that steps through 0.47 \u00b5m<\/a>, 0.64 \u00b5m<\/a>, 0.86 \u00b5m<\/a>, 1.61 \u00b5m<\/a> and 3.9 \u00b5m<\/a> imagery for one time on 7 March. The smoke plume is most distinct at the shortest wavelength 0.47 \u00b5m; it is very difficult to discern at 0.86 \u00b5m and especially at 1.61 \u00b5m because these near-infrared channels sense radiation at longer wavelengths that is unaffected by scattering of light by the small smoke particles. Note, however, that the small lakes do jump out at both wavelengths because of the very different reflectance properties of land and water at both 0.86 \u00b5m and 1.61 \u00b5m.<\/p>\n

Finally, compare the 0.64 \u00b5m<\/a> and 0.86 \u00b5m<\/a> with special focus on the burn scars (here<\/a> is a toggle between the two). Although the spatial resolution is greatest in the 0.64 \u00b5m visible imagery (0.5 km at the sub-satellite point, vs. 1 km at the sub-satellite point for the 0.86 \u00b5m imagery), the burn scars nevertheless are more distinct at 0.86 \u00b5m, in part because vegetated ground is more reflective at 0.86 \u00b5m than at 0.64 \u00b5m (See the figure in ‘Tim’s Topics’ on page 2 of the 0.86 \u00b5m fact sheet<\/a>).<\/p>\n

\"GOES-16<\/a>

GOES-16 imagery from 2227 UTC on 07 March 2017. Wavelengths indicated in the image [click to animate]<\/p><\/div>


\n=========================================================================<\/center>A less extensive fire event occurred on 10 March 2017 in Florida. Focus on the largest hot spot (black pixels) in the 3.9 \u00b5m imagery in the center of the top third of the image below; this point is in southeastern Polk County<\/a>. For this event, the smoke plume is more easily visualized in the 0.47 \u00b5m imagery than in the 0.64 \u00b5m or the 0.86 \u00b5m imagery. A burn scar does not appear in this case.<\/p>\n

\"GOES-16<\/a>

GOES-16 imagery from 1931 UTC on 10 March 2017. [click to animate]<\/p><\/div>The GOES-R<\/a> Website includes Fact Sheets for Band 1 (0.47 \u00b5m)<\/a>, Band 2 (0.64 \u00b5m)<\/a>, Band 3 (0.86 \u00b5m)<\/a>, Band 5 (1.61 \u00b5m)<\/a> and Band 7 (3.9 \u00b5m)<\/a>.<\/p>\n

AWIPS Note: The default enhancement (“IR_COLOR_CLOUDS_WINTER”) for 3.9 \u00b5m results in imagery that shows too little gradation over Florida during the daytime<\/a>; for fire detection, either modify the colormap (this<\/a> changed the temperature range from the default [-109 to 55] to -70 to 75, and is shown above) or switch to the”IR_COLOR_CLOUDS_SUMMER” enhancement.<\/p>\n","protected":false},"excerpt":{"rendered":"

The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Tweets on Tuesday 7 March 2017 highlighted the fast-moving fires over the High Plains (that began burning on 6 March), and they also highlighted different bands available from the GOES-16 ABI. For example, this tweet references the loop above, showing […]<\/p>\n","protected":false},"author":19,"featured_media":23360,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[6,74],"tags":[],"class_list":["post-23337","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\/23337","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=23337"}],"version-history":[{"count":35,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/23337\/revisions"}],"predecessor-version":[{"id":23377,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/23337\/revisions\/23377"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/23360"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=23337"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=23337"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=23337"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}