{"id":50288,"date":"2023-02-06T19:57:53","date_gmt":"2023-02-06T19:57:53","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=50288"},"modified":"2023-02-07T19:58:21","modified_gmt":"2023-02-07T19:58:21","slug":"sar-observations-near-american-samoa-part-iii","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/50288","title":{"rendered":"SAR Observations near American Samoa (part III)"},"content":{"rendered":"\n<p>Synthetic Aperture Radar (SAR) RADARSAT-2 observations continue in\/around the South Pacific Ocean surrounding American Samoa.  On 6 February, observations occurred at 0543 and 1640 UTC.  The toggle below compares the 0540 UTC Band 13 Clean Window infrared (10.3 \u00b5m) image with overlain SAR winds (color-enhanced with the AWIPS &#8216;gridded data&#8217; enhancement, with values from 0-50 knots).  This was a day with wind speeds around 10-12 knots over the ocean, with exception of a few lines of stronger winds.  As with previous events, the strongest winds in these SAR analyses are likely related to highly reflective ice in the clouds.  (<a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/RSAT2_GSS_2023_02_06_05_39_54_0728977194_168.39W_13.85S_VV_C_windspeed_nrcs_toggle.gif\">Here is a toggle<\/a> of the <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/RSAT2_GSS_2023_02_06_05_39_54_0728977194_168.39W_13.85S_VV_C5_GFS025CDF_wind.png\">wind analysis<\/a> and the Normalized Radar Cross Section <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/RSAT2_GSS_2023_02_06_05_39_54_0728977194_168.39W_13.85S_VV_C_nrcs.png\">NRCS analysis<\/a> taken from <a href=\"https:\/\/www.star.nesdis.noaa.gov\/socd\/mecb\/sar\/AKDEMO_products\/APL_winds\/wind_images_nic\/sarwinds_calendar_now.html\">this website<\/a>;  ice shows up as very bright white feathery structures in the NRCS imagery).<\/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\/02\/G18SARWinds-20230206_0539toggle.gif\"><img loading=\"lazy\" decoding=\"async\" width=\"1280\" height=\"841\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/G18SARWinds-20230206_0539toggle.gif\" alt=\"\" class=\"wp-image-50289\"\/><\/a><figcaption class=\"wp-element-caption\">GOES-18 ABI Clean Window Infrared (Band 13, 10.3 \u00b5m)  Imagery and RADARSAT-2 SAR Winds, 0540 UTC on 6 February 2023 (click to enlarge)<\/figcaption><\/figure>\n\n\n\n<p>The Shortwave Infrared (ABI Band 7, 3.9) mp4 animation, below, (from the <a href=\"https:\/\/geosphere.ssec.wisc.edu\/#coordinate:0,0;\">CSPP Geosphere<\/a> site;  <a href=\"https:\/\/geosphere.ssec.wisc.edu\/#playing:true;coordinate:-3109233,-1666065;zoom:5.9;satellite:goeswest;product:C07;map_grid:on;num_frames:20;start_time:2023-02-06T04:00:00Z;timeframe:Start%20Time;\">here&#8217;s the direct link<\/a>) shows the persistent westward motion of cloud features.<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video height=\"800\" style=\"aspect-ratio: 1486 \/ 800;\" width=\"1486\" controls loop src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/goeswest_abi_radf_C07_s20230206040021_e20230206071021_f20.mp4\"><\/video><figcaption class=\"wp-element-caption\"> GOES-18 Band 7 Shortwave Infrared (3.9 \u00b5m) imagery, 0400 &#8211; 0710 on 6 February 2023<\/figcaption><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>RADARSAT-2 also overflew American Samoa at 1643 UTC on 6 February.  The toggle below shows the derived SAR wind speed and the GOES-18 Clean Window infrared (Band 13, 10.3 \u00b5m) imagery at that time.  As with the morning pass, <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/RSAT2_GSS_2023_02_06_16_43_29_0729017009_168.35W_15.05S_VV_C5_GFS025CDF_wind.png\">the strongest winds<\/a> here are associated with ice crystals within the clouds, identifiable in the <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/RSAT2_GSS_2023_02_06_16_43_29_0729017009_168.35W_15.05S_VV_C_nrcs.png\">NRCS imagery<\/a> (<a href=\"https:\/\/www.star.nesdis.noaa.gov\/socd\/mecb\/sar\/AKDEMO_products\/APL_winds\/wind_images_nic\/sarwinds_daily_now.html?date=20230206\">link to original imagery<\/a>). <\/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\/02\/G18B13SARWinds-20230206_1643toggle.gif\"><img loading=\"lazy\" decoding=\"async\" width=\"1280\" height=\"841\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2023\/02\/G18B13SARWinds-20230206_1643toggle.gif\" alt=\"\" class=\"wp-image-50299\"\/><\/a><figcaption class=\"wp-element-caption\">RADARSAT-2 Derived SAR Wind Speeds and GOES-18 Clean Window infrared (Band 13, 10.3 \u00b5m) imagery, 1640 UTC on 6 February 2023 (Click to enlarge)<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Synthetic Aperture Radar (SAR) RADARSAT-2 observations continue in\/around the South Pacific Ocean surrounding American Samoa. On 6 February, observations occurred at 0543 and 1640 UTC. The toggle below compares the 0540 UTC Band 13 Clean Window infrared (10.3 \u00b5m) image with overlain SAR winds (color-enhanced with the AWIPS &#8216;gridded data&#8217; enhancement, with values from 0-50 [&hellip;]<\/p>\n","protected":false},"author":19,"featured_media":50296,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[114,104,25],"tags":[],"class_list":["post-50288","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-goes-18","category-sar","category-satellite-winds"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/50288","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=50288"}],"version-history":[{"count":2,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/50288\/revisions"}],"predecessor-version":[{"id":50303,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/50288\/revisions\/50303"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/50296"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=50288"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=50288"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=50288"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}