{"id":4014,"date":"2023-12-22T16:50:35","date_gmt":"2023-12-22T23:50:35","guid":{"rendered":"https:\/\/rammb.cira.colostate.edu\/training\/visit\/blog\/?p=4014"},"modified":"2026-03-06T09:06:25","modified_gmt":"2026-03-06T16:06:25","slug":"sunglint-solstice","status":"publish","type":"post","link":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/2023\/12\/22\/sunglint-solstice\/","title":{"rendered":"Sun Glint During the Southern Hemisphere\u2019s Summer Solstice"},"content":{"rendered":"<p>By Erin Sanders and Bernie Connell<\/p>\n<p>This year the second solstice occurred on December 21, 2023.\u00a0 In Earth\u2019s Northern Hemisphere this marks the start of astronomical winter and is the shortest day of the year in terms of possible daylight.\u00a0 In the Southern Hemisphere the opposite is true and is where we will turn our attention.<\/p>\n<p>The Amazon basin in South America is the drainage basin of the Amazon River.\u00a0 It\u2019s an extensive region with a river system that transports more water than anywhere else in the world.\u00a0 While we can explore the region with various satellite imagery and products at any time, there is one particularly interesting way to view it.\u00a0 Let me explain.\u00a0 Sun glint is an optical phenomenon that can be seen in visible and near-IR satellite imagery when sunlight is reflected off water surfaces towards the satellite sensor.\u00a0 It occurs with the right positioning between the Sun, Earth, and satellite viewing angle.\u00a0 While we typically notice sun glint over open ocean where it is the most obvious, it is not unusual to spot it over the continents if you know where to look.\u00a0 The following animation shows a small portion of the Amazon basin in Brazil, using recent GOES-16 0.64 \u00b5m visible imagery.<\/p>\n<div style=\"width: 1288px;\" class=\"wp-video\"><video class=\"wp-video-shortcode\" id=\"video-4014-1\" width=\"1288\" height=\"648\" preload=\"metadata\" controls=\"controls\"><source type=\"video\/mp4\" src=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_G16_B02_20231218.mp4?_=1\" \/><a href=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_G16_B02_20231218.mp4\">https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_G16_B02_20231218.mp4<\/a><\/video><\/div>\n<p><em>GOES-16 0.64\u00a0<\/em><em>\u00b5m visible imagery over Brazil on December 18, 2023 from 12:00-14:30 UTC.<\/em><\/p>\n<p>Here it is again for the same time period, but with GOES-16 3.9 \u00b5m imagery.<\/p>\n<div style=\"width: 1288px;\" class=\"wp-video\"><video class=\"wp-video-shortcode\" id=\"video-4014-2\" width=\"1288\" height=\"648\" preload=\"metadata\" controls=\"controls\"><source type=\"video\/mp4\" src=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_G16_B07_20231218.mp4?_=2\" \/><a href=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_G16_B07_20231218.mp4\">https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_G16_B07_20231218.mp4<\/a><\/video><\/div>\n<p><em>GOES-16 3.9 <\/em><em>\u00b5m imagery over Brazil on December 18, 2023 from 12:00-14:30 UTC.<\/em><\/p>\n<p>As the Sun moves overhead, sun glint appears east to west across the imagery highlighting the expansive water network of the Amazon basin, from major rivers to smaller bodies of water.\u00a0 As the rivers change course and diverge throughout the landscape they create stunning patterns similar to that of a lightning strike.\u00a0 It is most apparent in satellite imagery with the help of reflected solar radiation, and can be fun to spot in this region of South America when the Sun is south of the equator this time of year.<\/p>\n<p>There is another interesting feature related to sun glint that is occasionally seen and could be seen in the previous animations.\u00a0 Did you notice anything unusual? An arc of sun glint appears along a cloud edge around 13:20 UTC. These clouds are likely composed of ice crystals, and with the right viewing geometry creates a higher reflection of sunlight.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-4015 size-large alignleft\" src=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_20231218_labels-1024x720.png\" alt=\"\" width=\"640\" height=\"450\" srcset=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_20231218_labels-1024x720.png 1024w, https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_20231218_labels-300x211.png 300w, https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/river_sunglint_20231218_labels.png 2007w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/>\u00a0<em>GOES-16 0.64 <\/em><em>\u00b5m visible imagery over Brazil on December 18, 2023 at 13:20 UTC.<\/em><\/p>\n<p>Let\u2019s take a look at another example.\u00a0 Sun glint can be spotted year-round in satellite imagery, typically in the tropics.\u00a0 On the Southern Hemisphere\u2019s summer solstice, the Sun is aligned with the Tropic of Capricorn at roughly 23.4\u00b0 south latitude.\u00a0 This is the southernmost latitude where the Sun can be directly overhead, and we find sun glint extending the farthest south at this time of year.\u00a0 The following animation shows sun glint as far south as 67.5\u00b0 south latitude over the Southern Ocean.<\/p>\n<div style=\"width: 1208px;\" class=\"wp-video\"><video class=\"wp-video-shortcode\" id=\"video-4014-3\" width=\"1208\" height=\"686\" preload=\"metadata\" controls=\"controls\"><source type=\"video\/mp4\" src=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/south_sunglint_G16_B02_20231221.mp4?_=3\" \/><a href=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/south_sunglint_G16_B02_20231221.mp4\">https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/south_sunglint_G16_B02_20231221.mp4<\/a><\/video><\/div>\n<p><em>GOES-16 0.64 <\/em><em>\u00b5m imagery over the Southern Ocean on December 21, 2023 from 04:00-06:20 UTC.<\/em><\/p>\n<p>Were you able to find it? Although there is widespread cloud cover, there are clearings where open ocean and Antarctic sea ice peek through in the 0.64 \u00b5m satellite imagery.\u00a0 In these places we are able to see sun glint, as the area goes from dark to very bright to dark again in a short amount of time.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignleft wp-image-4016 size-large\" src=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/south_sunglint_20231221_labels-1024x481.png\" alt=\"\" width=\"640\" height=\"301\" srcset=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/south_sunglint_20231221_labels-1024x481.png 1024w, https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2023\/12\/south_sunglint_20231221_labels-300x141.png 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/p>\n<p><em>GOES-16 0.64 <\/em><em>\u00b5m visible imagery over the Southern Ocean on December 21, 2023 at 05:20 UTC.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>By Erin Sanders and Bernie Connell This year the second solstice occurred on December 21, 2023.\u00a0 In Earth\u2019s Northern Hemisphere this marks the start of astronomical winter and is the shortest day of the year in terms of possible daylight.\u00a0 In the Southern Hemisphere the opposite is true and is where we will turn our <a href=\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/2023\/12\/22\/sunglint-solstice\/\" class=\"more-link\">Continue Reading<\/a><\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[19],"tags":[],"class_list":["post-4014","post","type-post","status-publish","format-standard","hentry","category-miscellaneous"],"_links":{"self":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts\/4014","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/comments?post=4014"}],"version-history":[{"count":1,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts\/4014\/revisions"}],"predecessor-version":[{"id":6023,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts\/4014\/revisions\/6023"}],"wp:attachment":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/media?parent=4014"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/categories?post=4014"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/tags?post=4014"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}