{"id":48052,"date":"2022-09-23T19:53:59","date_gmt":"2022-09-23T19:53:59","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=48052"},"modified":"2022-09-23T19:53:59","modified_gmt":"2022-09-23T19:53:59","slug":"center-fixing-a-storm-with-sar-and-ssmis-data","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/48052","title":{"rendered":"Center-fixing a storm with SAR and SSMIS data"},"content":{"rendered":"\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"882\" height=\"712\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/Sentinel1AWindSpeedBeaufortScale-20220923_075712_37.png\" alt=\"\" class=\"wp-image-48053\" srcset=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/Sentinel1AWindSpeedBeaufortScale-20220923_075712_37.png 882w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/Sentinel1AWindSpeedBeaufortScale-20220923_075712_37-300x242.png 300w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/Sentinel1AWindSpeedBeaufortScale-20220923_075712_37-768x620.png 768w\" sizes=\"auto, (max-width: 882px) 100vw, 882px\" \/><figcaption>Sentinel SAR Wind Speeds, 0757 UTC on 23 September 2022 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n<p>Sentinel overflew Tropical Storm Gaston, northwest of the Azores Islands, shortly before 0800 UTC on 23 September 2022, as shown above.  The Beaufort Scale enhancement suggest peak winds derived from SAR observations to be very close to 50 knots in curved bands to the east\/southeast of the center, inferred to be just off the edge of observation swath, which is at 40.76<sup>o<\/sup> N Latitude, 29.3<sup>o<\/sup> W Longitude.  GOES-16 satellite imagery spanning this time around sunrise shows an exposed low-level circulation center with stronger convection building along the northern perimeter of the storm (mp4 animation shown <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/goeseast_abi_radf_true_color_night_s20220923070020_e20220923105020_f24.mp4\">here<\/a>, created with <a href=\"https:\/\/geosphere.ssec.wisc.edu\/#coordinate:0,0;\">CSPP Geosphere<\/a> &#8212; direct link is <a href=\"https:\/\/geosphere.ssec.wisc.edu\/#playing:true;coordinate:3244771,3761196;zoom:6.5;map_grid:on;num_frames:24;start_time:2022-09-23T07:00:00Z;timeframe:Start%20Time;\">here<\/a>).  Because GOES-16 can view the low-level circulation, the parallax shift of the center in the animation is small (smaller than the parallax shift in the SAR\/GOES-16 imagery shown <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/48027\">here<\/a> Fiona) even though Gaston is near the satellite limb.<\/p>\n\n\n\n<p>DMSP-17 carries the SSMIS (Special Sensor Microwave Imager\/Sensor) and overflew Gaston just after 0900 UTC, as shown below in an image from the <a rel=\"noreferrer noopener\" href=\"http:\/\/tropic.ssec.wisc.edu\" target=\"_blank\">SSEC Tropical Website<\/a>.  The estimated wind speed from this image is 52 knots, close to the SAR values shown above.  The <a href=\"https:\/\/www.nhc.noaa.gov\/archive\/2022\/al08\/al082022.discus.012.shtml?\">0900 UTC update<\/a> from the <a href=\"https:\/\/www.nhc.noaa.gov\">National Hurricane Center<\/a> showed a center at 40.5<sup>o<\/sup>N, 29.6<sup>o<\/sup>W and maximum sustained windspeeds at 50 knots.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"680\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/SSMIS85GHz_0911UTC_23Sept2022-1024x680.gif\" alt=\"\" class=\"wp-image-48054\" srcset=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/SSMIS85GHz_0911UTC_23Sept2022-1024x680.gif 1024w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/SSMIS85GHz_0911UTC_23Sept2022-300x199.gif 300w, https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/09\/SSMIS85GHz_0911UTC_23Sept2022-768x510.gif 768w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption>85 GHz observations from SSMIS-17, 0911 UTC on 23 September 2022 (Click to enlarge)<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Sentinel overflew Tropical Storm Gaston, northwest of the Azores Islands, shortly before 0800 UTC on 23 September 2022, as shown above. The Beaufort Scale enhancement suggest peak winds derived from SAR observations to be very close to 50 knots in curved bands to the east\/southeast of the center, inferred to be just off the edge [&hellip;]<\/p>\n","protected":false},"author":19,"featured_media":48053,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[56,79,47,104,2],"tags":[],"class_list":["post-48052","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-dmsp","category-microwave","category-other-satellites","category-sar","category-tropical-cyclones"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/48052","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=48052"}],"version-history":[{"count":1,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/48052\/revisions"}],"predecessor-version":[{"id":48056,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/48052\/revisions\/48056"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/48053"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=48052"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=48052"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=48052"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}