{"635503":{"#nid":"635503","#data":{"type":"news","title":"Volcanic Activity Does Not Contribute to El Ninos, Hard Evidence Says","body":[{"value":"\u003Cp\u003EHard data gained from fossilized corals have spoken strongly against a popular theoretical\u0026nbsp;assumption that volcanic activity may have influenced El Nino events.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EA study published in the journal\u0026nbsp;\u003Ca href=\u0022https:\/\/science.sciencemag.org\/lookup\/doi\/10.1126\/science.aax2000\u0022\u003EScience\u003C\/a\u003E in March and\u0026nbsp;led by researchers from Rice University and the Georgia Institute of Technology parsed the record archived by ancient tropical Pacific coral over the past millennium. That record could help scientists refine their models of how changing conditions in the Pacific influence the occurrence of\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/El_Ni%C3%B1o\u0022\u003EEl Ni\u0026ntilde;o events\u003C\/a\u003E, which are major drivers of global climate.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe researchers found that the ratio of oxygen isotopes sequestered in coral \u0026ndash; an accurate measure of historic ocean temperatures \u0026ndash; showed no correlation between El Ni\u0026ntilde;o events and estimates of\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/Sulfate_aerosol\u0022\u003Esulfate particles\u003C\/a\u003E\u0026nbsp;ejected into the atmosphere by tropical volcanic eruptions.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe coral data was collected on trips to the Pacific over the course of 20 years, by teams led by\u0026nbsp;\u003Ca href=\u0022http:\/\/shadow.eas.gatech.edu\/~kcobb\/people\/people.html\u0022\u003EKim Cobb\u003C\/a\u003E, a professor in Georgia Tech\u0026rsquo;s School of Earth and Atmospheric Science. Those coral records have shown little connection between known volcanoes and El Ni\u0026ntilde;o events over that time. Like tree rings, these\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/Paleoclimatology\u0022\u003Epaleoclimate\u003C\/a\u003E\u0026nbsp;archives have held chemical indicators, the oxygen isotopes, of oceanic conditions at the time they formed.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe corals\u0026nbsp;yield\u0026nbsp;a high-fidelity record that tracks\u0026nbsp;the\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/El_Ni%C3%B1o%E2%80%93Southern_Oscillation\u0022\u003EEl Ni\u0026ntilde;o-Southern Oscillation\u003C\/a\u003E\u0026nbsp;(ENSO) in the heart of the central tropical Pacific. The ENSO is a natural oscillation of hotter and cooler surface water temperatures that peak every few years to trigger El Ninos in the hot phases and La Ninas in the cool phases.\u003C\/p\u003E\r\n\r\n\u003Ch3\u003E\u003Cstrong\u003EChallenging established models\u003C\/strong\u003E\u003C\/h3\u003E\r\n\r\n\u003Cp\u003EAccording to Rice climate scientist and the study\u0026#39;s\u0026nbsp;corresponding author\u0026nbsp;\u003Ca href=\u0022https:\/\/sylviadeeclimate.org\/\u0022\u003ESylvia Dee\u003C\/a\u003E, previous climate model studies have tied volcanic eruptions, which increase sulfate aerosols in the atmosphere, to increased chances for an El Ni\u0026ntilde;o event. But the ability to analyze climate conditions based on oxygen isotopes trapped in fossil corals has extended the climatological record in this key region across more than 20 ancient eruptions. Dee said this has allowed for a more rigorous test of the connection.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026ldquo;A lot of climate modeling studies show a dynamical connection where volcanic eruptions can initiate El Ni\u0026ntilde;o events,\u0026rdquo; Dee said. \u0026ldquo;We can run climate models many centuries into the past, simulating volcanic eruptions for the last millennium. But the models are just that \u0026mdash; models \u0026mdash; and the coral record captures reality.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe coral records Cobb and her colleagues studied for this particular research held unambiguous markers of conditions over 319 years, from 1146-1465. This and data from other corals spans more than 500 years of the last millennium and, they wrote, \u0026ldquo;presents a window into the effects of large volcanic eruptions on tropical Pacific climate.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThat span of time includes the\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/1257_Samalas_eruption\u0022\u003E1257 eruption of Mt. Samalas\u003C\/a\u003E, the largest and most sulfurous of the last millennium.\u003C\/p\u003E\r\n\r\n\u003Ch3\u003E\u003Cstrong\u003EExpanding coral records\u003C\/strong\u003E\u003C\/h3\u003E\r\n\r\n\u003Cp\u003ECobb said her lab has been developing techniques and expanding the coral record for years.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026ldquo;My first expedition to the islands was in 1997, and it has been my sole focus pretty much since then to extract the best records that we can from these regions,\u0026rdquo; she said, noting the lab has issued many papers on the topic, including a groundbreaking 2003 study on ENSO in\u0026nbsp;\u003Ca href=\u0022https:\/\/www.nature.com\/articles\/nature01779\u0022\u003ENature\u003C\/a\u003E.\u003C\/p\u003E\r\n\r\n\u003Cp\u003ECobb said dating the ancient coral samples depends on precise\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/Uranium%E2%80%93thorium_dating\u0022\u003Euranium-thorium dating\u003C\/a\u003E, followed by thousands of mass spectrometric analyses of coral oxygen isotopes from powders drilled every 1 millimeter across the coral\u0026rsquo;s growth axis.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026ldquo;That speaks to the temperature reconstruction,\u0026rdquo; she said. \u0026ldquo;We\u0026rsquo;re borrowing on 70 years of work with this particular chemistry to establish a robust temperature proxy in corals.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe oxygen-16 to oxygen-18\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/Isotopes_of_oxygen\u0022\u003Eisotopes\u003C\/a\u003E\u0026nbsp;revealed by spectrometry show that the temperature of the water at the time the coral formed, Cobb said.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026ldquo;The ratio of those two isotopes in carbonates is a function of the temperature,\u0026rdquo; she said. \u0026ldquo;That\u0026rsquo;s the magic: It\u0026rsquo;s based on pure thermodynamics.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026ldquo;This beautiful coral record is highly sensitive to El Ni\u0026ntilde;o and\u0026nbsp;\u003Ca href=\u0022https:\/\/en.wikipedia.org\/wiki\/La_Ni%C3%B1a\u0022\u003ELa Ni\u0026ntilde;a\u003C\/a\u003E\u0026nbsp;events based on its location,\u0026rdquo; Dee added. \u0026ldquo;Scientists have reconstructed the timing of those volcanic eruptions from\u0026nbsp;\u003Ca href=\u0022https:\/\/www.bas.ac.uk\/data\/our-data\/publication\/ice-cores-and-climate-change\/\u0022\u003Eice-core records\u003C\/a\u003E. We compared the timing of the largest eruptions to the coral record to see if volcanic cooling events had any impact on tropical Pacific climate.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026ldquo;Our study suggests that linkage\u0026nbsp;doesn\u0026rsquo;t exist or, if it does, it is obscured by the large natural variability in the climate system,\u0026rdquo; Dee said. \u0026ldquo;In general, El Ni\u0026ntilde;o is a natural oscillator in the climate system.\u0026rdquo;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cem\u003ECo-authors of the paper were Julien Emile-Geay from the University of Southern California; Toby Ault from Cornell University; Lawrence Edwards from the University of Minnesota; research scientist Hai Cheng of Minnesota University and Xi\u0026rsquo;an Jiaotong University, China; and Christopher Charles from the University of California, San Diego. The research was funded by the National Science Foundation. Any findings, conclusions, or recommendations are those of the funding agencies and not necessarily of the sponsor.\u003C\/em\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ERice University media inquiries:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EMike Williams, writer\u003C\/strong\u003E\u003Cbr \/\u003E\r\n\u003Ca href=\u0022mailto:mikewilliams@rice.edu\u0022\u003Emikewilliams@rice.edu\u003C\/a\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EGeorgia Tech media inquiries:\u003C\/strong\u003E\u003Cbr \/\u003E\r\nBen Brumfield\u003Cbr \/\u003E\r\n\u003Ca href=\u0022mailto:ben.brumfield@comm.gatech.edu\u0022\u003Eben.brumfield@comm.gatech.edu\u003C\/a\u003E\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Physical evidence has spoken, and it clearly says that volcanic activity does not push El Nino and La Nina events."}],"uid":"31759","created_gmt":"2020-05-19 17:16:38","changed_gmt":"2020-05-19 17:25:31","author":"Ben Brumfield","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2020-05-19T00:00:00-04:00","iso_date":"2020-05-19T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"629307":{"id":"629307","type":"image","title":"El Nino globe images 1997 and 2015","body":null,"created":"1574694551","gmt_created":"2019-11-25 15:09:11","changed":"1574694551","gmt_changed":"2019-11-25 15:09:11","alt":"","file":{"fid":"239662","name":"El Ninos NOAA.jpg","image_path":"\/sites\/default\/files\/images\/El%20Ninos%20NOAA.jpg","image_full_path":"http:\/\/tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/El%20Ninos%20NOAA.jpg","mime":"image\/jpeg","size":213525,"path_740":"http:\/\/tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/El%20Ninos%20NOAA.jpg?itok=uAdSTjCF"}},"629311":{"id":"629311","type":"image","title":"Kim Cobb drills corals underwater in the tropical Pacific","body":null,"created":"1574694827","gmt_created":"2019-11-25 15:13:47","changed":"1574694827","gmt_changed":"2019-11-25 15:13:47","alt":"","file":{"fid":"239664","name":"Kim.Cobb_.drilling.JPG","image_path":"\/sites\/default\/files\/images\/Kim.Cobb_.drilling.JPG","image_full_path":"http:\/\/tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/Kim.Cobb_.drilling.JPG","mime":"image\/jpeg","size":554867,"path_740":"http:\/\/tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/Kim.Cobb_.drilling.JPG?itok=VIOqBxqz"}},"627918":{"id":"627918","type":"image","title":"Kim Cobb honored with 2020 Hans Oeschger Medal","body":null,"created":"1571775373","gmt_created":"2019-10-22 20:16:13","changed":"1571775373","gmt_changed":"2019-10-22 20:16:13","alt":"","file":{"fid":"239110","name":"2019 Final instagram Kim Cobb Medal .png","image_path":"\/sites\/default\/files\/images\/2019%20Final%20instagram%20Kim%20Cobb%20Medal%20.png","image_full_path":"http:\/\/tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/2019%20Final%20instagram%20Kim%20Cobb%20Medal%20.png","mime":"image\/png","size":737564,"path_740":"http:\/\/tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/2019%20Final%20instagram%20Kim%20Cobb%20Medal%20.png?itok=IRyyXq9q"}}},"media_ids":["629307","629311","627918"],"groups":[{"id":"1278","name":"College of Sciences"},{"id":"1214","name":"News Room"},{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"135","name":"Research"},{"id":"154","name":"Environment"}],"keywords":[{"id":"14760","name":"coral reef"},{"id":"184841","name":"coral record"},{"id":"183155","name":"Fossil Record"},{"id":"184842","name":"coral fossil record"},{"id":"184843","name":"volcanic activity"},{"id":"10994","name":"el nino"},{"id":"111321","name":"la nina"},{"id":"184844","name":"climate modeling"},{"id":"53861","name":"ENSO"},{"id":"183153","name":"El Nino Southern Oscillation"},{"id":"184845","name":"paleoclimate archives"},{"id":"184846","name":"sulfate aerosols"},{"id":"184847","name":"oxygen isotopes"},{"id":"184848","name":"uranium-thorium dating"}],"core_research_areas":[],"news_room_topics":[{"id":"71911","name":"Earth and Environment"},{"id":"71881","name":"Science and Technology"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}