{"id":72114,"date":"2026-09-05T10:59:00","date_gmt":"2026-09-05T10:59:00","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=72114"},"modified":"2026-09-13T02:50:39","modified_gmt":"2026-09-13T02:50:39","slug":"eruption-of-anak-krakatau-in-indonesia","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/72114","title":{"rendered":"Eruption of Anak Krakatau in Indonesia"},"content":{"rendered":"\n<figure class=\"wp-block-video aligncenter\"><video autoplay controls loop muted src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260904_260905_himawari9_ashRGB_Krakatau_anim.mp4\" playsinline><\/video><figcaption class=\"wp-element-caption\"><em>10-minute Himawari-9 Ash RGB images, from 1500 UTC on 04 September to 0620 UTC on 05 September<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><a href=\"https:\/\/www.jma.go.jp\/jma\/indexe.html\">JMA<\/a><\/strong> Himawari-9 <strong><a href=\"https:\/\/rammb2.cira.colostate.edu\/wp-content\/uploads\/2020\/01\/GOES_Ash_RGB-1.pdf\">Ash RGB<\/a><\/strong> images created using <strong><a href=\"https:\/\/www.ssec.wisc.edu\/software\/geo2grid\/\">Geo2Grid<\/a><\/strong> <strong><em>(above)<\/em><\/strong> showed a major eruption of <strong><a href=\"https:\/\/en.wikipedia.org\/wiki\/Anak_Krakatoa\">Anak Krakatau<\/a><\/strong> in Indonesia, which began around 1620 UTC on 04 September 2026. A middle-tropospheric volcanic ash cloud (depicted by shades of red to magenta) remained closer to the volcano &#8212; while an upper-tropospheric SO<sub>2<\/sub> cloud (shades of yellow-green) moved rapidly west-southwestward.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-rich is-provider-bluesky-social wp-block-embed-bluesky-social\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"bluesky-embed\" data-bluesky-uri=\"at:\/\/did:plc:54p7tmjjko2ek3yzuvareiwr\/app.bsky.feed.post\/3murmgbsnts2j\" data-bluesky-cid=\"bafyreibpqzculdgmkfq33pqtjrbifedxfcvzve32uhlag3c6pnpyqfsqvi\"><p lang=\"en\">Large #eruption of #Krakatau #volcano (#Indonesia) started at ~16:30 UTC on Sept 4, and is continuing as of 13:00 UTC on Sept 5. #NOAA-20 OMPS satellite data showing injection of ~0.2 Tg SO? into the upper troposphere by 06:50 UTC on Sep 5.<\/p>&mdash; <a href=\"https:\/\/bsky.app\/profile\/did:plc:54p7tmjjko2ek3yzuvareiwr?ref_src=embed\">Prof. Simon Carn (@simoncarn.bsky.social)<\/a> <a href=\"https:\/\/bsky.app\/profile\/did:plc:54p7tmjjko2ek3yzuvareiwr\/post\/3murmgbsnts2j?ref_src=embed\">2026-09-05T13:45:18.892Z<\/a><\/blockquote><script async src=\"https:\/\/embed.bsky.app\/static\/embed.js\" charset=\"utf-8\"><\/script>\n<\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">After sunrise on 05 September, Himawari-9 True Color RGB images <em><strong>(below)<\/strong><\/em> showed the middle-tropospheric volcanic ash cloud as shades of brown, with pulses of brighter white upper-tropospheric volcanic cloud (a mixture of water vapor, ash and SO<sub>2<\/sub>) moving quickly westward away from the volcano. Ash eventually drifted northward over parts of the island of Sumatra, and eastward over parts of the island of Java.<\/p>\n\n\n\n<figure class=\"wp-block-video aligncenter\"><video autoplay controls loop muted src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260905_himawari9_trueColorRGB_Krakatau_anim.mp4\" playsinline><\/video><figcaption class=\"wp-element-caption\"><em>10-minute Himawari-9 True Color RGB images, from 2340 UTC on 04 September to <\/em><em>1000 UTC on 05 September<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A radiometrically-retrieved Ash Height product from the <strong><a href=\"https:\/\/volcano.ssec.wisc.edu\">NOAA\/CIMSS Volcanic Cloud Monitoring<\/a><\/strong> site <strong><em>(below)<\/em><\/strong> indicated that ash from the eruption likely reached maximum altitudes in the 18-20 km range (black enhancement).<\/p>\n\n\n\n<figure class=\"wp-block-video aligncenter\"><video autoplay controls loop muted src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260904_260905_himawari9_ashHeight_Krakatau.mov\" playsinline><\/video><figcaption class=\"wp-element-caption\"><em>Himawari-9 Ash Height derived product, from 1500 UTC on 04 September to 1500 UTC on 05 September<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A plot of <strong><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260905_0000UTC_WIII_RAOB_DATA.TEXT\">rawinsonde data<\/a><\/strong> from Jakarta International Airport, located east of Krakatau on the island of Java <strong><em>(below)<\/em><\/strong> showed lighter and variable-direction winds in the mid-troposphere (within the 650-450 hPa pressure layer, or altitudes of 3.7-7.0 km), with stronger easterly winds in the upper troposphere (especially within the 300-200 hPa pressure layer, or altitudes of 9.7-12.5 km).<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260905_0000UTC_WIII_RAOB.GIF\"><img decoding=\"async\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260905_0000UTC_WIII_RAOB.GIF\" alt=\"\"\/><\/a><figcaption class=\"wp-element-caption\"><em>Plot of rawinsonde data from Jakarta International Airport at 0000 UTC on 05 September [click to enlarge]<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"has-text-align-center wp-block-paragraph\"><strong>===== 06 September Update =====<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-video aligncenter\"><video autoplay controls loop muted src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260906_himawari9_trueColorRGB_Krakatau_anim.mp4\" playsinline><\/video><figcaption class=\"wp-element-caption\"><em>10-minute Himawari-9 True Color RGB images, from 2340 UTC on 05 September to 1000 UTC on 06 September<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">On 06 September, Himawari-9 True Color RGB images <strong><em>(above)<\/em><\/strong> showed the hazy signature of residual lower-altitude volcanic ash across the region &#8212; although the ash was not as thick as on the previous day, so it did not exhibit the same shades-of-brown signature. Nearly 3000 flights were suspended from Jakarta International Airport during its 2-day closure after the eruption of Krakatau.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A NOAA-21 VIIRS Day\/Night Band image at 0533 UTC on 06 September <em><strong>(below)<\/strong><\/em> included a cursor sample of the Jakarta International Airport (identifier WIII) METAR observation, which included Volcanic Ash (VA).<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260906_0533utc_noaa21_viirs_dayNightBand_Krakatau.png\"><img decoding=\"async\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260906_0533utc_noaa21_viirs_dayNightBand_Krakatau.png\" alt=\"\"\/><\/a><figcaption class=\"wp-element-caption\"><em>NOAA-21 (mislabeled by AWIPS as NPP) VIIRS Day\/Night Band image, valid at 0533 UTC on 06 September &#8212; with a cursor sample of the Jakarta International Airport METAR observation at 0530 UTC [click to enlarge]<\/em><\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">A plot of surface observation data from Jakarta International Airport <strong><em>(below)<\/em><\/strong> indicated that Volcanic Ash was reported beginning at 1900 UTC on 05 September, with the volcanic ash restricting surface visibility to 4-7 miles.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260904_260906_WIII_SFCMG.GIF\"><img decoding=\"async\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2026\/09\/260904_260906_WIII_SFCMG.GIF\" alt=\"\"\/><\/a><figcaption class=\"wp-element-caption\"><em>Plot of surface observation data from Jakarta International Airport, from 1600 UTC on 04 September to 1600 UTC on 06 September [click to enlarge]<\/em><\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>JMA Himawari-9 Ash RGB images created using Geo2Grid (above) showed a major eruption of Anak Krakatau in Indonesia, which began around 1620 UTC on 04 September 2026. A middle-tropospheric volcanic ash cloud (depicted by shades of red to magenta) remained closer to the volcano &#8212; while an upper-tropospheric SO2 cloud (shades of yellow-green) moved rapidly [&hellip;]<\/p>\n","protected":false},"author":18,"featured_media":72116,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[7,21,132,73,131,45,48,9],"tags":[],"class_list":["post-72114","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-air-quality","category-aviation","category-geo2grid","category-himawari-9","category-noaa-21","category-redgreenblue-rgb-images","category-viirs","category-volcanic-activity"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/72114","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\/18"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=72114"}],"version-history":[{"count":43,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/72114\/revisions"}],"predecessor-version":[{"id":72203,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/72114\/revisions\/72203"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/72116"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=72114"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=72114"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=72114"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}