{"id":48704,"date":"2022-11-10T11:29:00","date_gmt":"2022-11-10T11:29:00","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=48704"},"modified":"2022-11-25T20:06:51","modified_gmt":"2022-11-25T20:06:51","slug":"sar-data-over-guam-part-iv","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/48704","title":{"rendered":"SAR data over Guam (part IV)"},"content":{"rendered":"\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/11\/H8Band13_SARWinds-20221110_0840toggle.gif\"><img loading=\"lazy\" decoding=\"async\" width=\"1342\" height=\"841\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/11\/H8Band13_SARWinds-20221110_0840toggle.gif\" alt=\"\" class=\"wp-image-48705\"\/><\/a><figcaption class=\"wp-element-caption\">Himawari Band 13 infrared imagery (10.4 \u00b5m) SAR winds from RADARSAT-2, 0840 UTC on 10 November 2022 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n<p>RADARSAT-2 overflew Guam early on 10 November 2022, and the toggle above shows both Himawari-8 imagery at that time with the SAR wind estimates overlain.  This was a time of light winds and minimal shower activity.  It&#8217;s interesting that the wake of weak winds downwind of the islands of Guam (and Rota) are apparent in this regime of weak easterly winds.  (Metop-B ASCAT winds from late on 9 November are <a href=\"https:\/\/manati.star.nesdis.noaa.gov\/ascat_images\/arch_25km_METB\/AS2022313\/zooms\/WMBds256.png\">here<\/a>, and late on 10 November are <a href=\"https:\/\/manati.star.nesdis.noaa.gov\/ascat_images\/arch_25km_METB\/AS2022314\/zooms\/WMBds256.png\">here<\/a>;  both images are from the <a href=\"https:\/\/manati.star.nesdis.noaa.gov\/\">NOAA\/NESDIS &#8216;manati&#8217; website<\/a>).<\/p>\n\n\n\n<p>A zoomed-in version of the image above is shown below.  The windspeed downwind of Guam shows downstream variations in speed, oriented north-south.  Those speed changes are very small, from 11-12 knots (cyan enhancement) to 8 or 9 knots (dark blue) enhancements.  The coldest cloud tops in the Himawari-8 imagery  &#8212; to the west of Guam &#8212; are associated with strong\/weak wind dipoles.  The region of stronger winds (around 18 knots, green in the enhancement used) to the west-northwest of Guam are associated with slightly cooler cloud tops, but this line of tropical convection has brightness temperatures in the 15-18<sup>o<\/sup>C range:  not very tall at all!<\/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\/2022\/11\/H8Band13SARWinds-20221110_084020Zoomtoggle.gif\"><img loading=\"lazy\" decoding=\"async\" width=\"1342\" height=\"841\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/11\/H8Band13SARWinds-20221110_084020Zoomtoggle.gif\" alt=\"\" class=\"wp-image-48706\"\/><\/a><figcaption class=\"wp-element-caption\">Himawari Band 13 infrared imagery (10.4 \u00b5m) SAR winds from RADARSAT, 0840 UTC on 10 November 2022 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n<p>Imagery is also available at the NOAA\/NESDIS STAR SAR Winds calendar <a href=\"https:\/\/www.star.nesdis.noaa.gov\/socd\/mecb\/sar\/AKDEMO_products\/APL_winds\/wind_images_nic\/sarwinds_calendar_now.html\">here<\/a>;  the <a href=\"https:\/\/www.star.nesdis.noaa.gov\/socd\/mecb\/sar\/AKDEMO_products\/APL_winds\/wind_images_nic\/2022-11\/RSAT2_GSS_2022_11_10_08_35_36_0721384536_143.50E_13.23N_VV_C5_GFS025CDF_wind.png\">wind speed<\/a> and the <a href=\"https:\/\/www.star.nesdis.noaa.gov\/socd\/mecb\/sar\/AKDEMO_products\/APL_winds\/wind_images_nic\/2022-11\/RSAT2_GSS_2022_11_10_08_35_36_0721384536_143.50E_13.23N_VV_C_nrcs.png\">Normalized Radar Cross Section<\/a> information are both available, and they are shown in a toggle below.<\/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\/2022\/11\/RSAT2_GSS_2022_11_10_08_35_36_0721384536_143.50E_13.23N_VV_C_nrcstoggle.gif\"><img loading=\"lazy\" decoding=\"async\" width=\"1824\" height=\"1955\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2022\/11\/RSAT2_GSS_2022_11_10_08_35_36_0721384536_143.50E_13.23N_VV_C_nrcstoggle.gif\" alt=\"\" class=\"wp-image-48710\"\/><\/a><figcaption class=\"wp-element-caption\">SAR Wind Speeds and Normalized Radar Cross Section (NRCS) imagery, 0835 UTC on 10 November 2022 (Click to enlarge)<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>RADARSAT-2 overflew Guam early on 10 November 2022, and the toggle above shows both Himawari-8 imagery at that time with the SAR wind estimates overlain. This was a time of light winds and minimal shower activity. It&#8217;s interesting that the wake of weak winds downwind of the islands of Guam (and Rota) are apparent in [&hellip;]<\/p>\n","protected":false},"author":19,"featured_media":48707,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[62,104],"tags":[],"class_list":["post-48704","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-himawari-8","category-sar"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/48704","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=48704"}],"version-history":[{"count":4,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/48704\/revisions"}],"predecessor-version":[{"id":48840,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/48704\/revisions\/48840"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/48707"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=48704"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=48704"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=48704"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}