{"575171":{"#nid":"575171","#data":{"type":"news","title":"A Look Inside Volcanic Flows","body":[{"value":"\u003Cp\u003EAn empty boiler house and 1.5 tons of thick volcanic ash have given researchers at New Zealand\u2019s Massey University and Georgia Tech a look into the inner workings of pyroclastic flows in the largest-scale experiments of volcanic flows that have been conducted. They saw something they didn\u2019t expect.\u003C\/p\u003E\u003Cp\u003EIn a \u003Ca href=\u0022http:\/\/www.nature.com\/ngeo\/journal\/vaop\/ncurrent\/full\/ngeo2794.html\u0022\u003Epaper published last week by Nature Geoscience\u003C\/a\u003E, the team describes two separate transport areas that have been well-studied: a non-turbulent underflow and a fully turbulent, ash cloud region at the top of the flow. But volcanic flows apparently have a previously unrecognized third zone where the currents meet.\u003C\/p\u003E\u003Cp\u003E\u201cInside this middle zone, the gas-particle mixture behaved fundamentally differently from the turbulent suspension cloud above and the particle-rich avalanche of pumice below,\u201d said Massey\u2019s Gert Lube. \u201cThese mesoscale turbulence clusters control how the internal structure and the damage potential of pyroclastic flows evolves during volcanic events.\u201d\u003C\/p\u003E\u003Cp\u003EPyroclastic flows, like the ones that covered Pompeii, are avalanches of fast-moving clouds of hot ash, rock and gas that are emitted during eruptions. They are responsible for 50 percent of volcanic fatalities every year.\u003C\/p\u003E\u003Cp\u003E\u201cOur experiments allow us to better understand the physics of something we\u2019ll never see: the inside of an actual volcanic flow,\u201d said Massey\u2019s Eric Breard, the lead author who will begin a postdoctoral fellowship at Georgia Tech in January. \u201cBy studying how quickly this mesoscale region grows, and how its dynamics change, it ultimately can tell us how dangerous the flows can be.\u201d\u0026nbsp;\u003C\/p\u003E\u003Cp\u003ETo create and measure the flows, the team used Massey\u2019s one-of-a-kind eruption simulator. The team climbed a 12-meter tower in a repurposed boiler house and poured more than 3,500 pounds of pumice and ash down a 12-meter narrow chute. High-speed cameras recorded the flow while sensors captured the data.\u003C\/p\u003E\u003Cp\u003E\u201cThese experiments demonstrated that in the intermediate transition zone between the fully turbulent upper part of the flow and the underlying concentrated underflow, the energy from the largest scales of fluid motion is extracted by particles that almost exactly follow the fluid motion,\u201d said co-author Josef Dufek, an associate professor at Georgia Tech. \u201cThis creates dendritic structures, or waves of particles, that slow the flow down, and provide the rate-limiting step for particles entering the underflow where they can cause the most damage.\u201d \u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u201cThis opens a new path toward reliable predictions of their motion, and will be particularly topical for hazard scientists and decision makers, because they will lead to major revisions of volcanic hazard forecasts and ultimately more effective measures for keeping people safe,\u201d said Lube.\u003C\/p\u003E\u003Cp\u003EMassey and Georgia Tech also received support from scientists at the University of Auckland and State University of New York.\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003E\u003Cstrong\u003ECo-written by Ryan Willoughby of Massey University.\u003C\/strong\u003E\u003C\/em\u003E\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Research attempts to better understand deadly pyroclastic flows"}],"field_summary":[{"value":"\u003Cp\u003EIn a paper published by Nature Geoscience, the team describes two separate transport areas that have been well-studied: a non-turbulent underflow and a fully turbulent, ash cloud region at the top of the flow. But volcanic flows apparently have a previously unrecognized third zone where the currents meet.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"But volcanic flows apparently have a previously unrecognized third zone where the currents meet."}],"uid":"27560","created_gmt":"2016-09-12 09:47:11","changed_gmt":"2022-05-26 17:09:36","author":"Jason Maderer","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2016-09-12T00:00:00-04:00","iso_date":"2016-09-12T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"575261":{"id":"575261","type":"image","title":"Eruption simulator","body":null,"created":"1473691644","gmt_created":"2016-09-12 14:47:24","changed":"1475894460","gmt_changed":"2016-10-08 02:41:00","alt":"Eruption simulator","file":{"fid":"207199","name":"pyroclastic.jpg","image_path":"\/sites\/default\/files\/images\/pyroclastic.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/pyroclastic.jpg","mime":"image\/jpeg","size":74304,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/pyroclastic.jpg?itok=IbM6j93J"}},"128081":{"id":"128081","type":"image","title":"Josef Dufek","body":null,"created":"1449178622","gmt_created":"2015-12-03 21:37:02","changed":"1475894751","gmt_changed":"2016-10-08 02:45:51","alt":"Josef Dufek","file":{"fid":"194562","name":"dufek.jpg","image_path":"\/sites\/default\/files\/images\/dufek_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/dufek_0.jpg","mime":"image\/jpeg","size":1027944,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/dufek_0.jpg?itok=TbHJckUk"}}},"media_ids":["575261","128081"],"groups":[{"id":"1183","name":"Home"}],"categories":[],"keywords":[{"id":"32491","name":"Josef Dufek"},{"id":"172322","name":"Pyroclastic Flows"},{"id":"27001","name":"Volcano"}],"core_research_areas":[{"id":"39521","name":"Robotics"}],"news_room_topics":[{"id":"71911","name":"Earth and Environment"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EJason Maderer - National Media Relations\u003C\/p\u003E","format":"limited_html"}],"email":["maderer@gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}