{"id":35678,"date":"2020-12-03T08:14:17","date_gmt":"2020-12-03T08:14:17","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=35678"},"modified":"2020-12-04T01:14:13","modified_gmt":"2020-12-04T01:14:13","slug":"guinobatan-lahar","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2020\/12\/03\/guinobatan-lahar\/","title":{"rendered":"High resolution satellite images of the Guinobatan lahar"},"content":{"rendered":"<h4>High resolution satellite images of the Guinobatan lahar<\/h4>\n<p>A month ago, <a href=\"https:\/\/en.wikipedia.org\/wiki\/Typhoon_Goni_(2020)\">Typhoon Goni (known locally as Rolly)<\/a> brought heavy rainfall to the Philippines, causing extensive damage.&nbsp; One of the most serious events triggered by the typhoon was the <a href=\"https:\/\/blogs.agu.org\/landslideblog\/2020\/11\/19\/guinobatan\/\">Guinobatan lahar, which flowed down the flanks of Mount Mayon, an active stratovolcano<\/a>.<\/p>\n<p><a href=\"https:\/\/www.planet.com\/\">Plant Labs<\/a> have very kindly collected and processed high resolution satellite imagery of the aftermath of the lahar.&nbsp; Once again I thank them for their support and for making this amazing imagery available &#8211; it is transformative in our understanding of these events.<\/p>\n<p>This is an image of the area affected by the lahar, collected on 23 October 2018:<\/p>\n<div id=\"attachment_35681\" style=\"width: 809px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-35681\" class=\" wp-image-35681\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-1.jpg\" alt=\"Guinobatan lahar - before\" width=\"799\" height=\"449\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-1.jpg 1920w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-1-300x169.jpg 300w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-1-1024x576.jpg 1024w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-1-768x432.jpg 768w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-1-1536x864.jpg 1536w\" sizes=\"auto, (max-width: 799px) 100vw, 799px\" \/><p id=\"caption-attachment-35681\" class=\"wp-caption-text\">The area affected by the Guinobatan lahar before the event. <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a> SkySat image, copyright <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a>, used with permission.<\/p><\/div>\n<p>.<\/p>\n<p>And in contrast, this is an image of the aftermath of the lahar, collected on 14 November 2020:-<\/p>\n<div id=\"attachment_35683\" style=\"width: 809px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-35683\" class=\" wp-image-35683\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-2.jpg\" alt=\"Guinobatan lahar\" width=\"799\" height=\"449\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-2.jpg 1920w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-2-300x169.jpg 300w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-2-1024x576.jpg 1024w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-2-768x432.jpg 768w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/12\/20_12-Guinobatan-2-1536x864.jpg 1536w\" sizes=\"auto, (max-width: 799px) 100vw, 799px\" \/><p id=\"caption-attachment-35683\" class=\"wp-caption-text\">The aftermath of the Guinobatan lahar. <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a> SkySat image, copyright <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a>, used with permission.<\/p><\/div>\n<p>.<\/p>\n<p><a href=\"https:\/\/cdn.knightlab.com\/libs\/juxtapose\/latest\/embed\/index.html?uid=f2d256f0-353f-11eb-83c8-ebb5d6f907df\">I have used Juxtapose to create a slider that allows comparison of the images<\/a>.<\/p>\n<p>In the image before the lahar the existing channel cuts through the settlement.&nbsp; There is a hint that lahars have affected a much wider area, especially in the upper central part of the image where there considerable areas of sparse vegetation.<\/p>\n<p>In the second image it is clear that the Guinobatan lahar overflowed the channel upstream of the houses, spreading over a large area.&nbsp; Indeed the main flow appears to have followed a different path altogether, penetrating a long distance into the settlement.&nbsp; There are a large number of houses affected.<\/p>\n<p>Interestingly, the lahar has reoccupied some abandoned channels, especially on the eastern side.&nbsp; There are other abandoned channels that this event has not reoccupied.<\/p>\n<p>These images serve to highlight the hazards posed by lahars, the vulnerability of settlements to them and the repeat nature of these events.<\/p>\n<p>.<\/p>\n<h4>Reference and acknowledgement<\/h4>\n<p>Planet Team (2020). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. <a href=\"https:\/\/www.planet.com\/\">https:\/\/www.planet.com\/<\/a><\/p>\n<!-- AddThis Advanced Settings generic via filter on the_content --><!-- AddThis Share Buttons generic via filter on the_content -->","protected":false},"excerpt":{"rendered":"<p>High resolution satellite images, collected by Planet Labs using the SkySat constellation, showing the impact of the Guinobatan lahar in the Philippines a month ago<!-- AddThis Advanced Settings generic via filter on wp_trim_excerpt --><!-- AddThis Share Buttons generic via filter on wp_trim_excerpt --><\/p>\n","protected":false},"author":22,"featured_media":35692,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[469,34,252,1205,521,314,975],"class_list":["post-35678","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-featured","tag-lahar","tag-philippines","tag-planet-labs","tag-satellite-image","tag-se-asia","tag-typhoon"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/35678","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/comments?post=35678"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/35678\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/35692"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=35678"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=35678"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=35678"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}