{"id":186,"date":"2011-05-24T02:49:57","date_gmt":"2011-05-24T01:49:57","guid":{"rendered":"http:\/\/all-geo.org\/volcan01010\/?p=186"},"modified":"2011-05-25T00:16:55","modified_gmt":"2011-05-24T23:16:55","slug":"ash-sampling","status":"publish","type":"post","link":"https:\/\/all-geo.org\/volcan01010\/2011\/05\/ash-sampling\/","title":{"rendered":"An easy way to sample falling ash (updated to include wet sampling)"},"content":{"rendered":"<p>Ash from the ongoing Gr\u00edmsv\u00f6tn eruption is predicted to arrive over the UK from Wednesday morning.\u00a0 At the moment it is hard to tell what it will be like.\u00a0 Certainly, it will not be like the scenes in Iceland where it has blanketed the ground like sandy grey snow.\u00a0 Perhaps it will just make the rain a bit dirty.\u00a0 During last year&#8217;s Eyjafjallaj\u00f6kull eruption, people across the UK reported ash grains in the air or grey dust spoiling their newly-cleaned cars.<\/p>\n<p>It would be amazing if we could make a map of all the places in the UK where people see ash falling.\u00a0 The results would be extremely useful to help test the predictions of ash dispersion  made by computer models.\u00a0 Also, ash layers from past eruptions are found  in lakes and peat bogs across Europe and are used by archaeologists to  correlate the ages of ancient settlements and remains.\u00a0 If we can  measure how the ash falls in a current eruption, it will help us  understand how layers from past eruptions have formed.<\/p>\n<h3>Coordinated sampling effort<\/h3>\n<p>The <a href=\"http:\/\/www.bgs.ac.uk\">British Geological Survey<\/a> are coordinating a nationwide collection of ash during the current Gr\u00edmsv\u00f6tn eruption.\u00a0 If ash falls where you live, then they want a sample!<\/p>\n<p>A simple procedure has been put together to help you to collect a useful sample.\u00a0 You can read more about it on the <a href=\"http:\/\/www.bgs.ac.uk\/research\/highlights\/GrimsvotnAshCollection.html\">BGS Gr\u00edmsv\u00f6tn Ash Collection website<\/a>.\u00a0 It is very quick and easy.\u00a0 If you see ash falling, then get out your sellotape and see if you can get a sample.\u00a0 The following video demonstrates the method:<\/p>\n<p><iframe loading=\"lazy\" title=\"Easy methods for collecting falling volcanic ash\" width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/IycXVWEuZuA?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/p>\n<h3>What the samples can tell us<\/h3>\n<p>The two methods of sample collection shown in the video can be used when ash is falling from the sky.\u00a0 The first, and easiest method, results in a paper &#8216;slide&#8217; that can be looked at under a microscope.<\/p>\n<div id=\"attachment_188\" style=\"width: 610px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-188\" class=\"size-full wp-image-188\" src=\"http:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/17052011068.jpg\" alt=\"A paper slide under the microscope\" width=\"600\" height=\"450\" srcset=\"https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/17052011068.jpg 600w, https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/17052011068-300x225.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><p id=\"caption-attachment-188\" class=\"wp-caption-text\">A paper &#039;slide&#039; being examined under the microscope.<\/p><\/div>\n<p>If the grains are big enough, it will be possible to recognise whether  they are ash or not and, using the very important information written on  the paper, to make a map of where ash fell.\u00a0 It is important that if you decide to take a sample, that you send it in.\u00a0 Even if it doesn&#8217;t look like it has much on it.\u00a0 We also need to know where ash is <em>not<\/em> falling.<\/p>\n<p style=\"text-align: center\">\n<div id=\"attachment_189\" style=\"width: 610px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-189\" class=\"size-full wp-image-189  \" src=\"http:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/paper_slide_16x_small.jpg\" alt=\"Ash grains on a paper slide\" width=\"600\" height=\"439\" srcset=\"https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/paper_slide_16x_small.jpg 600w, https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/paper_slide_16x_small-300x219.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><p id=\"caption-attachment-189\" class=\"wp-caption-text\">Ash grains on a paper slide can be identified based on their colour, their shape and whether they contain bubbles or small crystals.  Each sample can be checked quickly to see if it contains ash.  The most important information is where in the UK ash was actually falling.<\/p><\/div>\n<p>The second method is a bit more complicated, but allows the samples to be examined by the Scanning Electron Microscope (SEM).\u00a0 An SEM can take images at over 1000x magnification, letting us see small details of the ash such has how bubbly it is.\u00a0 It can also show if tiny ash grains have clumped together into bigger ones, called aggregates.\u00a0 The SEM is even able to give us a rough idea of the chemical elements that the ash contains.<\/p>\n<p style=\"text-align: center\">\n<div id=\"attachment_187\" style=\"width: 610px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-187\" class=\"size-full wp-image-187  \" src=\"http:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/aggregate.jpg\" alt=\"Aggregate grain under SEM\" width=\"600\" height=\"553\" srcset=\"https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/aggregate.jpg 1024w, https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/aggregate-300x276.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><p id=\"caption-attachment-187\" class=\"wp-caption-text\">An SEM image of an &#039;aggregate&#039; grain from the 2010 Eyjafjallaj\u00f6kull eruption.  This grain fell near Loughborough.  It is made of tiny particles stuck together.  The grain is tiny.  It is only 100 microns long, which means that 10 of these grains could fit in a millimetre.  Aircraft and satellites detected grains that were even smaller.<\/p><\/div>\n<h3>Sampling in the rain<\/h3>\n<p>It&#8217;s fairly windy and rainy across the UK today and tomorrow.\u00a0 A lot of the ash will come down with the rain.\u00a0 An easy way to collect this is by putting out the biggest saucepan that you have.<\/p>\n<ol>\n<li>Put the saucepan on a raised platform, so that dust blowing near the ground doesn&#8217;t get in.\u00a0 Make sure that it has a clear view of the sky and is away from trees etc.<\/li>\n<li>Fill the saucepan with 2 cm of water.\u00a0 This will give it some weight to stop it blowing away, and the water will trap any particles that fall when it isn&#8217;t raining so that the wind can&#8217;t pick them up again.\u00a0 Leave it out until the cloud has passed (estimated to be by Thursday night).\n<p><div id=\"attachment_221\" style=\"width: 610px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-221\" class=\"size-full wp-image-221\" src=\"http:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/saucepan.jpg\" alt=\"A saucepan out to collect wet samples\" width=\"600\" height=\"450\" srcset=\"https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/saucepan.jpg 600w, https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/saucepan-300x225.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><p id=\"caption-attachment-221\" class=\"wp-caption-text\">A saucepan can be used to collect wet samples.  Place it on a raised surface, away from trees.  Here a car roof is used, with a towel to protect the paintwork.  Putting water in the saucepan weighs it down and helps it trap ash.<\/p><\/div><\/li>\n<li>When you bring the saucepan inside, scoop any floating debris e.g. leaves\/insects from the surface (a sieve is handy for this).\u00a0 At this stage, it might not look like you have much, but persevere as the ash grains may be very small.<\/li>\n<li>Now we need to get rid of the water.\u00a0 Swirl the water, then place the saucepan beside your sink, using a wooden spoon to tilt it so that ash collects along one edge.\u00a0 Leave it for 5 minutes; this gives all the grains time to sink to the bottom.\u00a0 Then use a spoon to scoop out most of the water, trying not to disturb the ash.\u00a0 Don&#8217;t move the saucepan.\u00a0 This bit is quite tricky.\u00a0 If you stir the water up by accident, leave it for another 5 minutes then continue.\n<p><div id=\"attachment_222\" style=\"width: 610px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-222\" class=\"size-full wp-image-222\" src=\"http:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/sink.jpg\" alt=\"Preparing to spoon out the extra water.\" width=\"600\" height=\"450\" srcset=\"https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/sink.jpg 600w, https:\/\/all-geo.org\/volcan01010\/wp-content\/uploads\/2011\/05\/sink-300x225.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><p id=\"caption-attachment-222\" class=\"wp-caption-text\">Excess water is spooned out of the saucepan.  Tilting it on a wooden spoon concentrates the ash at one side and lets you get more water out.<\/p><\/div><\/li>\n<li>The rest of the water is gently evaporated off, either by leaving the saucepan on a radiator, or by putting it in the oven at 60 deg C.\u00a0 The water should not boil.\u00a0 Depending on how much water is in the pan, this could take a few hours.<\/li>\n<li>When you are sure that things are dry, use a piece of sticky tape (~10 cm long) to &#8216;mop&#8217; up all the grains.<\/li>\n<li>Stick the tape to a piece of plain white paper and label with the same information as the other tape samples (example below).\u00a0 Measure your saucepan, then add the following to the label:\u00a0 WET SAMPLE &#8211; SAUCEPAN DIAMETER XX CM.\u00a0 If you have lots of material, use more tape and stick it to the same paper strip.<\/li>\n<li>Send in the sample as normal.<\/li>\n<\/ol>\n<h3>Important information to include on label<\/h3>\n<p>An ash sample is useless if we don&#8217;t know where or when it was collected, or over what area.\u00a0 Any samples should be labelled with the following information:<\/p>\n<p><strong>Postcode<\/strong> (e.g. M20 4LZ)<br \/>\n<strong>Town<\/strong>: (e.g. Manchester)<br \/>\n<strong>Date<\/strong>: (e.g. 22 May 2011)<br \/>\n<strong>Sample collection time<\/strong>: (e.g. 13.00 &#8211; 21.00)<br \/>\n<strong>Email address<\/strong>: (e.g. a.b@c.com)<br \/>\n<strong>Extra collection information<\/strong>: (e.g. WET SAMPLE &#8211; SAUCEPAN DIAMETER 22cm)<\/p>\n<p>The time information may need a start date and an end date.<\/p>\n<h3>We need data from all over the country<\/h3>\n<p>We need samples from all over the country, so tell all your friends.\u00a0 The Hebrides, the Highlands and Northern Ireland are the areas predicted to see the most ash.\u00a0 But don&#8217;t let that stop you if you live further from the volcano.\u00a0 Perhaps your town can get the record for &#8220;Furthest South&#8221; or &#8220;Furthest East&#8221; confirmed Gr\u00edmsv\u00f6tn ash.\u00a0 Also, the call for samples is not restricted to within the UK.\u00a0 If any ash makes it to mainland Europe, then those samples would also be extremely welcome.<\/p>\n<p>Happy sampling!<\/p>\n<p>(Updated 24 May, 23.21 hrs.\u00a0 Reason &#8211; wet sampling method added).<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Ash from the ongoing Gr\u00edmsv\u00f6tn eruption is predicted to arrive over the UK from Wednesday morning.\u00a0 At the moment it is hard to tell what it will be like.\u00a0 Certainly, it will not be like the scenes in Iceland where &hellip; <a href=\"https:\/\/all-geo.org\/volcan01010\/2011\/05\/ash-sampling\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-186","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/posts\/186","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/comments?post=186"}],"version-history":[{"count":18,"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/posts\/186\/revisions"}],"predecessor-version":[{"id":220,"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/posts\/186\/revisions\/220"}],"wp:attachment":[{"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/media?parent=186"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/categories?post=186"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/all-geo.org\/volcan01010\/wp-json\/wp\/v2\/tags?post=186"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}