{"id":606,"date":"2008-07-08T05:26:00","date_gmt":"2008-07-08T05:26:00","guid":{"rendered":"http:\/\/blogs.agu.org\/landslideblog\/2008\/07\/08\/rockfalls-from-the-eiger\/"},"modified":"2010-10-21T13:55:13","modified_gmt":"2010-10-21T17:55:13","slug":"rockfalls-from-the-eiger","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2008\/07\/08\/rockfalls-from-the-eiger\/","title":{"rendered":"Rockfalls from the Eiger"},"content":{"rendered":"

In 2006 Hans Rudolf Keusen<\/span> of Geotest<\/span><\/a> raised concerns that a large pillar on the Eiger<\/span> mountain in Switzerland had become unstable. Over the next few weeks the pillar did indeed progressively fail, providing some amazing images of a large rockfall in action (Fig 1):<\/p>\n

\"\"<\/a>Figure 1:<\/span> AP image<\/a> entitled: On July 13, 2006, masses of rock fell down from Eiger<\/span>, near Grindelwald<\/span>. The event came after days of warnings from scientists regarding rock loosened by melting glacial ice.<\/span><\/span><\/div>\n

\n

Yesterday, Hans Rudolf Keusen<\/span> again warned of the dangers of summer rockfalls on the Eiger<\/span>. Once again, rockfalls have been occurring on the northwest side of the mountain, associated with the melting of the Lower Grindelwald<\/span> glacier, which has left the flank of the mountain unsupported. The concern this time is that a rockfall could fall into a small lake at the toe of the slope, displacing “up to 900,000 cubic metres of water…in the space of several hours” (see here<\/a>). Fortunately, monitoring systems are in place to detect any sudden rises in lake level, so a warning should be available.<\/p>\n

The Swiss Glacier Monitoring Network<\/a> has a rather nice image of the glacier in question (Fig. 2):<\/p>\n

\"\"<\/a>Fig 2. <\/span>Swiss Glacier Monitoring Network<\/a> image of the Lower Grindelwald<\/span> glacier, showing the debuttressed<\/span> slopes above the moraines deposited by the glacier as it retreated.<\/span><\/span><\/div>\n

The magnitude of the problem is well-illustrated by annual monitoring<\/span> data that they have collected on the length of the glacier (Fig. 3). This shows the dramatic retreat of the glacier over a century, in which more than a kilometre has been lost. Unfortunately the data only extends to 1983, but the current average retreat rate is about 20 m per year.<\/p>\n

\"\"<\/a>Fig 3. <\/span>Swiss Glacier Monitoring Network graph<\/a> of the length of the Lower Grindelwald<\/span> glacier in the period 1879 to 1983.<\/span><\/span><\/div>\n","protected":false},"excerpt":{"rendered":"

In 2006 Hans Rudolf Keusen of Geotest raised concerns that a large pillar on the Eiger mountain in Switzerland had become unstable. Over the next few weeks the pillar did indeed progressively fail, providing some amazing images of a large rockfall in action (Fig 1): Figure 1: AP image entitled: On July 13, 2006, masses of rock fell down from Eiger, near Grindelwald. The event came after days of warnings …<\/p>\n","protected":false},"author":22,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_members_access_role":[],"_members_access_error":""},"categories":[1],"tags":[333,447,446,56],"class_list":["post-606","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-333","tag-alps","tag-eiger","tag-rockfall"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/606","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=606"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/606\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=606"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=606"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=606"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}