{"id":149974,"date":"2013-11-25T15:00:42","date_gmt":"2013-11-25T20:00:42","guid":{"rendered":"\/gazette\/?p=149974"},"modified":"2019-04-10T15:37:48","modified_gmt":"2019-04-10T19:37:48","slug":"u-s-methane-emissions-far-exceed-government-estimates","status":"publish","type":"post","link":"https:\/\/news.harvard.edu\/gazette\/story\/2013\/11\/u-s-methane-emissions-far-exceed-government-estimates\/","title":{"rendered":"U.S. methane emissions exceed government estimates"},"content":{"rendered":"\n\t
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This NOAA tall tower greenhouse gas observatory near Moody, Texas, collects data on methane in the atmosphere. The report also indicates that the contribution from livestock operations may be twice as high as previously thought. Photo courtesy of NOAA's Earth System Research Laboratory<\/p>

Photo by Roy Kaltschmidt\/Lawrence Berkeley National Laboratory<\/p><\/figcaption><\/figure>\n\n\t

\n\t\t\t\n\t\t\tScience & Tech\t\t<\/a>\n\t\t\n\t\t

\n\t\tU.S. methane emissions exceed government estimates\t<\/h1>\n\n\t\n\t\t\t<\/div>\n\t\t\n\t
\n\t\t
\n\t\t\t
\n\t\t\t\t\t

\n\t\tCaroline Perry\t<\/p>\n\t\t\t

\n\t\t\tSEAS Communications\t\t<\/p>\n\t\t\t\t\t<\/address>\n\t\t<\/div>\n\n\t\t

\n\t\t\tCollaborative study indicates fossil fuel extraction, animal husbandry major contributors\t\t<\/h2>\n\t\t\n<\/header>\n\n\n\n
\n\n\n\t\t

Emissions of methane from fossil fuel extraction and refining activities in the South Central United States are nearly five times higher than previous estimates, according to researchers at Harvard University<\/a> and seven other institutions. Their study, published this week in Proceedings of the National Academy of Sciences (PNAS),<\/a> also suggests that the contribution from livestock operations may be twice as high as previously thought.<\/p>\n

Methane, a potent greenhouse gas, is produced through natural gas production and distribution, cattle farming, landfills, coal mining, manure management, and other anthropogenic and natural sources, though human activities are thought to contribute approximately 60 percent of the total.<\/p>\n

Overall, according to the new study, total methane emissions in the United States appear to be 1.5 times and 1.7 times higher than the amounts previously estimated by the U.S. Environmental Protection Agency<\/a> (EPA) and the international Emissions Database for Global Atmospheric Research<\/a> (EDGAR), respectively.<\/p>\n

The difference lies in the methodology. The EPA and EDGAR use a bottom-up approach, calculating total emissions based on \u201cemissions factors\u201d \u2014 the amount of methane typically released per cow or per unit of coal or natural gas sold, for example. The new study takes a top-down approach, measuring what is actually present in the atmosphere and then using meteorological data and statistical analysis to trace it back to regional sources.<\/p>\n

Generated by a large, multi-institutional team of researchers, the latest findings offer a comprehensive baseline for assessing policies designed to reduce greenhouse gases. They also point to a few areas where the assumptions built into recent emissions factors and estimated totals may be flawed.<\/p>\n

\u201cThe bottom-up and top-down approaches give us very different answers about the level of methane gas emissions,\u201d notes lead author Scot M. Miller, a doctoral student in Earth and Planetary Sciences<\/a> through the Harvard Graduate School of Arts and Sciences<\/a>. \u201cMost strikingly, our results are higher by a factor of 2.7 over the South Central United States, which we know is a key region for fossil-fuel extraction and refining. It will be important to resolve that discrepancy in order to fully understand the impact of these industries on methane emissions.\u201d<\/p>\n

Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures.<\/p><\/blockquote>\n

Miller is a 2007 graduate of Harvard College and earned a master\u2019s degree in engineering sciences at the Harvard School of Engineering and Applied Sciences<\/a> (SEAS) in 2013. He studies in the lab of Steven C. Wofsy<\/a>, Abbott Lawrence Rotch Professor of Atmospheric and Environmental Science at SEAS.<\/p>\n

\u201cWhen we measure methane gas at the atmospheric level, we\u2019re seeing the cumulative effect of emissions that are happening at the surface across a very large region,\u201d says Wofsy, a co-author of the PNAS <\/i>study. \u201cThat includes the sources that were part of the bottom-up inventories, but maybe also things they didn\u2019t think to measure.\u201d<\/p>\n

Miller and Wofsy, along with colleagues at the Carnegie Institution for Science<\/a>, the National Oceanic and Atmospheric Administration<\/a> (NOAA), and five other institutions, used a combination of observation and modeling to conduct their analysis.<\/p>\n

NOAA and the U.S. Department of Energy collect observations of methane and other gases from the tops of telecommunications towers, typically about as tall as the Empire State Building, and during research flights. The team combined this data with meteorological models of the temperatures, winds, and movement of air masses from the same time period, and then used a statistical method known as geostatistical inverse modeling to essentially run the model backward and determine the methane\u2019s origin.<\/p>\n

The team also compared these results with regional economic and demographic data, as well as other information that provided clues to the sources \u2014 for example, data on human populations, livestock populations, electricity production from power plants, oil and natural gas production, production from oil refineries, rice production, and coal production. In addition, they drew correlations between methane levels and other gases that were observed at the time. For example, a high correlation between levels of methane and propane in the south-central region suggests a significant role for fossil fuels there.<\/p>\n

\u201cThis paper provides the most solid and the most detailed estimate to date of total U.S. methane emissions,\u201d says co-author Anna M. Michalak<\/a>, a faculty member in the Department of Global Ecology at the Carnegie Institution for Science. Michalak is also an associate professor of environmental Earth system science at Stanford University. \u201cThis was really, from beginning to end, just a very clean analysis.\u201d<\/p>\n

Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures. It also encourages the formation of surface ozone in cities and affects other aspects of atmospheric chemistry.<\/p>\n

Seeking to establish a baseline against which to measure future change in methane emissions, the researchers compared observational data collected in 2007\u201308 with EDGAR and EPA data for the same year (using the revised EPA data for 2007\u201308 that was published in April 2013). Future studies will apply the same analysis to present-day data.<\/p>\n

\u201cThe beauty of the approach we\u2019re using is that, because we\u2019re taking measurements in the atmosphere, which carry with them a signature of everything that happened upwind, we get a very strong number on what that total should be,\u201d says Michalak. \u201cNow that we know the total does not equal the sum of the parts, that means that either some of those parts are not what we thought they were, or there are some parts that are simply missing from the inventories. It really offers an opportunity for governments to re-examine the inventories in light of what we now know.\u201d<\/p>\n

In addition to Miller, Wofsy, and Michalak, co-authors included Eric A. Kort<\/a>, S.M. \u201905, Ph.D. \u201911, who is now a faculty member at the University of Michigan, Ann Arbor; Arlyn E. Andrews, Ph.D. \u201900, Edward J. Dlugokencky, and Stephen A. Montzka at NOAA\u2019s Earth System Research Laboratory; Sebastien C. Biraud and Marc L. Fischer at Lawrence Berkeley National Laboratory; Janusz Eluszkiewicz and Thomas Nehrkorn at Atmospheric and Environmental Research in Lexington, Mass.; Greet Janssens-Maenhout at the European Commission Joint Research Centre in Italy; and Ben R. Miller, John B. Miller, and Colm Sweeney at the University of Colorado Boulder.<\/p>\n\n\n<\/div>\n\n\t\t","protected":false},"excerpt":{"rendered":"

Emissions of methane from fossil fuel extraction and refining activities in the United States are nearly five times higher than previous estimates, according to researchers at Harvard University and seven other institutions. <\/p>\n","protected":false},"author":105622744,"featured_media":149976,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"gz_ga_pageviews":13,"gz_ga_lastupdated":"2019-01-12 04:09","document_color_palette":"crimson","author":"Caroline Perry","affiliation":"SEAS Communications","_category_override":"","_yoast_wpseo_primary_category":"","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1387],"tags":[5033,7257,8543,8546,8639,12463,13050,13597,14832,14966,23706,25189,25571,27742,27788,29171,30621,30714,30821,32322,34540],"gazette-formats":[],"series":[],"class_list":["post-149974","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-science-technology","tag-atmosphere","tag-caroline-perry","tag-climate","tag-climate-change","tag-coal","tag-environment","tag-fas","tag-fossil-fuels","tag-graduate-student","tag-greenhouse-gases","tag-methane","tag-natural-gas","tag-news-hub","tag-policy","tag-pollution","tag-research","tag-school-of-engineering-and-applied-sciences","tag-scot-m-miller","tag-seas","tag-steven-c-wofsy","tag-u-s-department-of-energy"],"yoast_head":"\nU.S. methane emissions exceed government estimates — Harvard Gazette<\/title>\n<meta name=\"description\" content=\"Emissions of methane from fossil fuel extraction and refining activities in the United States are nearly five times higher than previous estimates, according to researchers at Harvard University and seven other institutions.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/news.harvard.edu\/gazette\/story\/2013\/11\/u-s-methane-emissions-far-exceed-government-estimates\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"U.S. methane emissions exceed government estimates — Harvard Gazette\" \/>\n<meta property=\"og:description\" content=\"Emissions of methane from fossil fuel extraction and refining activities in the United States are nearly five times higher than previous estimates, according to researchers at Harvard University and seven other institutions.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/news.harvard.edu\/gazette\/story\/2013\/11\/u-s-methane-emissions-far-exceed-government-estimates\/\" \/>\n<meta property=\"og:site_name\" content=\"Harvard Gazette\" \/>\n<meta property=\"article:published_time\" content=\"2013-11-25T20:00:42+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2019-04-10T19:37:48+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2013\/11\/methane_photo3_605.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"605\" \/>\n\t<meta property=\"og:image:height\" content=\"403\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"harvardgazette\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/news.harvard.edu\/gazette\/story\/2013\/11\/u-s-methane-emissions-far-exceed-government-estimates\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/news.harvard.edu\/gazette\/story\/2013\/11\/u-s-methane-emissions-far-exceed-government-estimates\/\"},\"author\":{\"name\":\"harvardgazette\",\"@id\":\"https:\/\/news.harvard.edu\/gazette\/#\/schema\/person\/78d028cf624923e92682268709ffbc4b\"},\"headline\":\"U.S. methane emissions exceed government estimates\",\"datePublished\":\"2013-11-25T20:00:42+00:00\",\"dateModified\":\"2019-04-10T19:37:48+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/news.harvard.edu\/gazette\/story\/2013\/11\/u-s-methane-emissions-far-exceed-government-estimates\/\"},\"wordCount\":1094,\"publisher\":{\"@id\":\"https:\/\/news.harvard.edu\/gazette\/#organization\"},\"image\":{\"@id\":\"https:\/\/news.harvard.edu\/gazette\/story\/2013\/11\/u-s-methane-emissions-far-exceed-government-estimates\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/news.harvard.edu\/wp-content\/uploads\/2013\/11\/methane_photo3_605.jpg\",\"keywords\":[\"atmosphere\",\"Caroline Perry\",\"Climate\",\"Climate Change\",\"coal\",\"Environments & Sustainability\",\"FAS\",\"Fossil Fuels\",\"Graduate student\",\"Greenhouse Gases\",\"Methane\",\"Natural gas\",\"News Hub\",\"Policy\",\"Pollution\",\"Research\",\"School of Engineering and Applied Sciences\",\"Scot M. 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change\",\"coal\",\"environments & sustainability\",\"fas\",\"fossil fuels\",\"graduate student\",\"greenhouse gases\",\"methane\",\"natural gas\",\"news hub\",\"policy\",\"pollution\",\"research\",\"school of engineering and applied sciences\",\"scot m. miller\",\"seas\",\"steven c. wofsy\",\"u.s. department of energy\"],\"dateCreated\":\"2013-11-25T20:00:42Z\",\"datePublished\":\"2013-11-25T20:00:42Z\",\"dateModified\":\"2019-04-10T19:37:48Z\"}<\/script>","tracker_url":"https:\/\/cdn.parsely.com\/keys\/news.harvard.edu\/p.js"},"jetpack_featured_media_url":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2013\/11\/methane_photo3_605.jpg","has_blocks":true,"block_data":{"0":{"blockName":"harvard-gazette\/article-header","attrs":{"blockColorPalette":"","coloredHeading":"","creditText":"Photo by Roy Kaltschmidt\/Lawrence Berkeley National Laboratory","displayDetails":"","displayTitle":"","categoryId":1387,"mediaAlt":"","mediaCaption":"This NOAA tall tower greenhouse gas observatory near Moody, Texas, collects data on methane in the atmosphere. The report also indicates that the contribution from livestock operations may be twice as high as previously thought. Photo courtesy of NOAA's Earth System Research Laboratory","mediaId":149976,"mediaSize":"full","mediaType":"image","mediaUrl":"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2013\/11\/methane_photo3_605.jpg","poster":"","title":"U.S. methane emissions exceed government estimates","subheading":"Collaborative study indicates fossil fuel extraction, animal husbandry major contributors","centeredImage":true,"className":"is-style-full-width-text-below","mediaHeight":403,"mediaWidth":605,"backgroundFixed":false,"backgroundTone":"light","coloredBackground":false,"displayOverlay":true,"fadeInText":false,"isAmbient":false,"mediaLength":"","mediaPosition":"","posterText":"","titleAbove":false,"useUncroppedImage":false,"lock":[],"metadata":[]},"innerBlocks":[],"innerHTML":"<figure class=\"wp-block-image\"><img alt=\"\" height=\"403\" loading=\"eager\" src=\"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2013\/11\/methane_photo3_605.jpg\" width=\"605\"\/><figcaption class=\"wp-element-caption\"><p class=\"wp-element-caption--caption\">This NOAA tall tower greenhouse gas observatory near Moody, Texas, collects data on methane in the atmosphere. The report also indicates that the contribution from livestock operations may be twice as high as previously thought. Photo courtesy of NOAA's Earth System Research Laboratory<\/p><p class=\"wp-element-caption--credit\">Photo by Roy Kaltschmidt\/Lawrence Berkeley National Laboratory<\/p><\/figcaption><\/figure>\n","innerContent":["<figure class=\"wp-block-image\"><img alt=\"\" height=\"403\" loading=\"eager\" src=\"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2013\/11\/methane_photo3_605.jpg\" width=\"605\"\/><figcaption class=\"wp-element-caption\"><p class=\"wp-element-caption--caption\">This NOAA tall tower greenhouse gas observatory near Moody, Texas, collects data on methane in the atmosphere. The report also indicates that the contribution from livestock operations may be twice as high as previously thought. Photo courtesy of NOAA's Earth System Research Laboratory<\/p><p class=\"wp-element-caption--credit\">Photo by Roy Kaltschmidt\/Lawrence Berkeley National Laboratory<\/p><\/figcaption><\/figure>\n"],"rendered":"<header\n\tclass=\"wp-block-harvard-gazette-article-header alignfull article-header is-style-full-width-text-below centered-image\"\n\tstyle=\" \"\n>\n\t<figure class=\"wp-block-image\"><img alt=\"\" height=\"403\" loading=\"eager\" src=\"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2013\/11\/methane_photo3_605.jpg\" width=\"605\"\/><figcaption class=\"wp-element-caption\"><p class=\"wp-element-caption--caption\">This NOAA tall tower greenhouse gas observatory near Moody, Texas, collects data on methane in the atmosphere. The report also indicates that the contribution from livestock operations may be twice as high as previously thought. Photo courtesy of NOAA's Earth System Research Laboratory<\/p><p class=\"wp-element-caption--credit\">Photo by Roy Kaltschmidt\/Lawrence Berkeley National Laboratory<\/p><\/figcaption><\/figure>\n\n\t<div class=\"article-header__content\">\n\t\t\t<a\n\t\t\tclass=\"article-header__category\"\n\t\t\thref=\"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/\"\n\t\t>\n\t\t\tScience & Tech\t\t<\/a>\n\t\t\n\t\t<h1 class=\"article-header__title wp-block-heading \">\n\t\tU.S. methane emissions exceed government estimates\t<\/h1>\n\n\t\n\t\t\t<\/div>\n\t\t\n\t<div class=\"article-header__meta\">\n\t\t<div class=\"wp-block-post-author\">\n\t\t\t<address class=\"wp-block-post-author__content\">\n\t\t\t\t\t<p class=\"author wp-block-post-author__name\">\n\t\tCaroline Perry\t<\/p>\n\t\t\t<p class=\"wp-block-post-author__byline\">\n\t\t\tSEAS Communications\t\t<\/p>\n\t\t\t\t\t<\/address>\n\t\t<\/div>\n\n\t\t<time class=\"article-header__date\" datetime=\"2013-11-25\">\n\t\t\tNovember 25, 2013\t\t<\/time>\n\n\t\t<span class=\"article-header__reading-time\">\n\t\t\t6 min read\t\t<\/span>\n\t<\/div>\n\n\t\n\t\t\t<h2 class=\"article-header__subheading wp-block-heading\">\n\t\t\tCollaborative study indicates fossil fuel extraction, animal husbandry major contributors\t\t<\/h2>\n\t\t\n<\/header>\n"},"2":{"blockName":"core\/group","attrs":{"templateLock":false,"metadata":{"name":"Article content"},"align":"wide","layout":{"type":"constrained","justifyContent":"center"},"tagName":"div","lock":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","ariaLabel":"","anchor":""},"innerBlocks":[{"blockName":"core\/freeform","attrs":{"content":"","lock":[],"metadata":[]},"innerBlocks":[],"innerHTML":"\n\t\t<p>Emissions of methane from fossil fuel extraction and refining activities in the South Central United States are nearly five times higher than previous estimates, according to researchers at <a href=\"http:\/\/www.harvard.edu\/\">Harvard University<\/a> and seven other institutions. Their study, published this week in <a href=\"http:\/\/www.pnas.org\/\">Proceedings of the National Academy of Sciences (PNAS),<\/a> also suggests that the contribution from livestock operations may be twice as high as previously thought.<\/p>\n<p>Methane, a potent greenhouse gas, is produced through natural gas production and distribution, cattle farming, landfills, coal mining, manure management, and other anthropogenic and natural sources, though human activities are thought to contribute approximately 60 percent of the total.<\/p>\n<p>Overall, according to the new study, total methane emissions in the United States appear to be 1.5 times and 1.7 times higher than the amounts previously estimated by the <a href=\"http:\/\/epa.gov\/climatechange\/ghgemissions\/usinventoryreport.html\">U.S. Environmental Protection Agency<\/a> (EPA) and the international <a href=\"http:\/\/edgar.jrc.ec.europa.eu\/index.php\">Emissions Database for Global Atmospheric Research<\/a> (EDGAR), respectively.<\/p>\n<p>The difference lies in the methodology. The EPA and EDGAR use a bottom-up approach, calculating total emissions based on \u201cemissions factors\u201d \u2014 the amount of methane typically released per cow or per unit of coal or natural gas sold, for example. The new study takes a top-down approach, measuring what is actually present in the atmosphere and then using meteorological data and statistical analysis to trace it back to regional sources.<\/p>\n<p>Generated by a large, multi-institutional team of researchers, the latest findings offer a comprehensive baseline for assessing policies designed to reduce greenhouse gases. They also point to a few areas where the assumptions built into recent emissions factors and estimated totals may be flawed.<\/p>\n<p>\u201cThe bottom-up and top-down approaches give us very different answers about the level of methane gas emissions,\u201d notes lead author Scot M. Miller, a doctoral student in <a href=\"http:\/\/eps.harvard.edu\/\">Earth and Planetary Sciences<\/a> through the <a href=\"http:\/\/gsas.harvard.edu\/\">Harvard Graduate School of Arts and Sciences<\/a>. \u201cMost strikingly, our results are higher by a factor of 2.7 over the South Central United States, which we know is a key region for fossil-fuel extraction and refining. It will be important to resolve that discrepancy in order to fully understand the impact of these industries on methane emissions.\u201d<\/p>\n<blockquote><p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures.<\/p><\/blockquote>\n<p>Miller is a 2007 graduate of Harvard College and earned a master\u2019s degree in engineering sciences at the <a href=\"http:\/\/seas.harvard.edu\">Harvard School of Engineering and Applied Sciences<\/a> (SEAS) in 2013. He studies in the lab of <a href=\"http:\/\/www.seas.harvard.edu\/directory\/swofsy\">Steven C. Wofsy<\/a>, Abbott Lawrence Rotch Professor of Atmospheric and Environmental Science at SEAS.<\/p>\n<p>\u201cWhen we measure methane gas at the atmospheric level, we\u2019re seeing the cumulative effect of emissions that are happening at the surface across a very large region,\u201d says Wofsy, a co-author of the PNAS<i> <\/i>study. \u201cThat includes the sources that were part of the bottom-up inventories, but maybe also things they didn\u2019t think to measure.\u201d<\/p>\n<p>Miller and Wofsy, along with colleagues at the <a href=\"http:\/\/carnegiescience.edu\/\">Carnegie Institution for Science<\/a>, the <a href=\"http:\/\/www.noaa.gov\/\">National Oceanic and Atmospheric Administration<\/a> (NOAA), and five other institutions, used a combination of observation and modeling to conduct their analysis.<\/p>\n<p>NOAA and the U.S. Department of Energy collect observations of methane and other gases from the tops of telecommunications towers, typically about as tall as the Empire State Building, and during research flights. The team combined this data with meteorological models of the temperatures, winds, and movement of air masses from the same time period, and then used a statistical method known as geostatistical inverse modeling to essentially run the model backward and determine the methane\u2019s origin.<\/p>\n<p>The team also compared these results with regional economic and demographic data, as well as other information that provided clues to the sources \u2014 for example, data on human populations, livestock populations, electricity production from power plants, oil and natural gas production, production from oil refineries, rice production, and coal production. In addition, they drew correlations between methane levels and other gases that were observed at the time. For example, a high correlation between levels of methane and propane in the south-central region suggests a significant role for fossil fuels there.<\/p>\n<p>\u201cThis paper provides the most solid and the most detailed estimate to date of total U.S. methane emissions,\u201d says co-author <a href=\"http:\/\/dge.stanford.edu\/labs\/michalaklab\/index.html\">Anna M. Michalak<\/a>, a faculty member in the Department of Global Ecology at the Carnegie Institution for Science. Michalak is also an associate professor of environmental Earth system science at Stanford University. \u201cThis was really, from beginning to end, just a very clean analysis.\u201d<\/p>\n<p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures. It also encourages the formation of surface ozone in cities and affects other aspects of atmospheric chemistry.<\/p>\n<p>Seeking to establish a baseline against which to measure future change in methane emissions, the researchers compared observational data collected in 2007\u201308 with EDGAR and EPA data for the same year (using the revised EPA data for 2007\u201308 that was published in April 2013). Future studies will apply the same analysis to present-day data.<\/p>\n<p>\u201cThe beauty of the approach we\u2019re using is that, because we\u2019re taking measurements in the atmosphere, which carry with them a signature of everything that happened upwind, we get a very strong number on what that total should be,\u201d says Michalak. \u201cNow that we know the total does not equal the sum of the parts, that means that either some of those parts are not what we thought they were, or there are some parts that are simply missing from the inventories. It really offers an opportunity for governments to re-examine the inventories in light of what we now know.\u201d<\/p>\n<p>In addition to Miller, Wofsy, and Michalak, co-authors included <a href=\"http:\/\/aoss-research.engin.umich.edu\/faculty\/kort\/\">Eric A. Kort<\/a>, S.M. \u201905, Ph.D. \u201911, who is now a faculty member at the University of Michigan, Ann Arbor; Arlyn E. Andrews, Ph.D. \u201900, Edward J. Dlugokencky, and Stephen A. Montzka at NOAA\u2019s Earth System Research Laboratory; Sebastien C. Biraud and Marc L. Fischer at Lawrence Berkeley National Laboratory; Janusz Eluszkiewicz and Thomas Nehrkorn at Atmospheric and Environmental Research in Lexington, Mass.; Greet Janssens-Maenhout at the European Commission Joint Research Centre in Italy; and Ben R. Miller, John B. Miller, and Colm Sweeney at the University of Colorado Boulder.<\/p>\n","innerContent":["\n\t\t<p>Emissions of methane from fossil fuel extraction and refining activities in the South Central United States are nearly five times higher than previous estimates, according to researchers at <a href=\"http:\/\/www.harvard.edu\/\">Harvard University<\/a> and seven other institutions. Their study, published this week in <a href=\"http:\/\/www.pnas.org\/\">Proceedings of the National Academy of Sciences (PNAS),<\/a> also suggests that the contribution from livestock operations may be twice as high as previously thought.<\/p>\n<p>Methane, a potent greenhouse gas, is produced through natural gas production and distribution, cattle farming, landfills, coal mining, manure management, and other anthropogenic and natural sources, though human activities are thought to contribute approximately 60 percent of the total.<\/p>\n<p>Overall, according to the new study, total methane emissions in the United States appear to be 1.5 times and 1.7 times higher than the amounts previously estimated by the <a href=\"http:\/\/epa.gov\/climatechange\/ghgemissions\/usinventoryreport.html\">U.S. Environmental Protection Agency<\/a> (EPA) and the international <a href=\"http:\/\/edgar.jrc.ec.europa.eu\/index.php\">Emissions Database for Global Atmospheric Research<\/a> (EDGAR), respectively.<\/p>\n<p>The difference lies in the methodology. The EPA and EDGAR use a bottom-up approach, calculating total emissions based on \u201cemissions factors\u201d \u2014 the amount of methane typically released per cow or per unit of coal or natural gas sold, for example. The new study takes a top-down approach, measuring what is actually present in the atmosphere and then using meteorological data and statistical analysis to trace it back to regional sources.<\/p>\n<p>Generated by a large, multi-institutional team of researchers, the latest findings offer a comprehensive baseline for assessing policies designed to reduce greenhouse gases. They also point to a few areas where the assumptions built into recent emissions factors and estimated totals may be flawed.<\/p>\n<p>\u201cThe bottom-up and top-down approaches give us very different answers about the level of methane gas emissions,\u201d notes lead author Scot M. Miller, a doctoral student in <a href=\"http:\/\/eps.harvard.edu\/\">Earth and Planetary Sciences<\/a> through the <a href=\"http:\/\/gsas.harvard.edu\/\">Harvard Graduate School of Arts and Sciences<\/a>. \u201cMost strikingly, our results are higher by a factor of 2.7 over the South Central United States, which we know is a key region for fossil-fuel extraction and refining. It will be important to resolve that discrepancy in order to fully understand the impact of these industries on methane emissions.\u201d<\/p>\n<blockquote><p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures.<\/p><\/blockquote>\n<p>Miller is a 2007 graduate of Harvard College and earned a master\u2019s degree in engineering sciences at the <a href=\"http:\/\/seas.harvard.edu\">Harvard School of Engineering and Applied Sciences<\/a> (SEAS) in 2013. He studies in the lab of <a href=\"http:\/\/www.seas.harvard.edu\/directory\/swofsy\">Steven C. Wofsy<\/a>, Abbott Lawrence Rotch Professor of Atmospheric and Environmental Science at SEAS.<\/p>\n<p>\u201cWhen we measure methane gas at the atmospheric level, we\u2019re seeing the cumulative effect of emissions that are happening at the surface across a very large region,\u201d says Wofsy, a co-author of the PNAS<i> <\/i>study. \u201cThat includes the sources that were part of the bottom-up inventories, but maybe also things they didn\u2019t think to measure.\u201d<\/p>\n<p>Miller and Wofsy, along with colleagues at the <a href=\"http:\/\/carnegiescience.edu\/\">Carnegie Institution for Science<\/a>, the <a href=\"http:\/\/www.noaa.gov\/\">National Oceanic and Atmospheric Administration<\/a> (NOAA), and five other institutions, used a combination of observation and modeling to conduct their analysis.<\/p>\n<p>NOAA and the U.S. Department of Energy collect observations of methane and other gases from the tops of telecommunications towers, typically about as tall as the Empire State Building, and during research flights. The team combined this data with meteorological models of the temperatures, winds, and movement of air masses from the same time period, and then used a statistical method known as geostatistical inverse modeling to essentially run the model backward and determine the methane\u2019s origin.<\/p>\n<p>The team also compared these results with regional economic and demographic data, as well as other information that provided clues to the sources \u2014 for example, data on human populations, livestock populations, electricity production from power plants, oil and natural gas production, production from oil refineries, rice production, and coal production. In addition, they drew correlations between methane levels and other gases that were observed at the time. For example, a high correlation between levels of methane and propane in the south-central region suggests a significant role for fossil fuels there.<\/p>\n<p>\u201cThis paper provides the most solid and the most detailed estimate to date of total U.S. methane emissions,\u201d says co-author <a href=\"http:\/\/dge.stanford.edu\/labs\/michalaklab\/index.html\">Anna M. Michalak<\/a>, a faculty member in the Department of Global Ecology at the Carnegie Institution for Science. Michalak is also an associate professor of environmental Earth system science at Stanford University. \u201cThis was really, from beginning to end, just a very clean analysis.\u201d<\/p>\n<p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures. It also encourages the formation of surface ozone in cities and affects other aspects of atmospheric chemistry.<\/p>\n<p>Seeking to establish a baseline against which to measure future change in methane emissions, the researchers compared observational data collected in 2007\u201308 with EDGAR and EPA data for the same year (using the revised EPA data for 2007\u201308 that was published in April 2013). Future studies will apply the same analysis to present-day data.<\/p>\n<p>\u201cThe beauty of the approach we\u2019re using is that, because we\u2019re taking measurements in the atmosphere, which carry with them a signature of everything that happened upwind, we get a very strong number on what that total should be,\u201d says Michalak. \u201cNow that we know the total does not equal the sum of the parts, that means that either some of those parts are not what we thought they were, or there are some parts that are simply missing from the inventories. It really offers an opportunity for governments to re-examine the inventories in light of what we now know.\u201d<\/p>\n<p>In addition to Miller, Wofsy, and Michalak, co-authors included <a href=\"http:\/\/aoss-research.engin.umich.edu\/faculty\/kort\/\">Eric A. Kort<\/a>, S.M. \u201905, Ph.D. \u201911, who is now a faculty member at the University of Michigan, Ann Arbor; Arlyn E. Andrews, Ph.D. \u201900, Edward J. Dlugokencky, and Stephen A. Montzka at NOAA\u2019s Earth System Research Laboratory; Sebastien C. Biraud and Marc L. Fischer at Lawrence Berkeley National Laboratory; Janusz Eluszkiewicz and Thomas Nehrkorn at Atmospheric and Environmental Research in Lexington, Mass.; Greet Janssens-Maenhout at the European Commission Joint Research Centre in Italy; and Ben R. Miller, John B. Miller, and Colm Sweeney at the University of Colorado Boulder.<\/p>\n"],"rendered":"\n\t\t<p>Emissions of methane from fossil fuel extraction and refining activities in the South Central United States are nearly five times higher than previous estimates, according to researchers at <a href=\"http:\/\/www.harvard.edu\/\">Harvard University<\/a> and seven other institutions. Their study, published this week in <a href=\"http:\/\/www.pnas.org\/\">Proceedings of the National Academy of Sciences (PNAS),<\/a> also suggests that the contribution from livestock operations may be twice as high as previously thought.<\/p>\n<p>Methane, a potent greenhouse gas, is produced through natural gas production and distribution, cattle farming, landfills, coal mining, manure management, and other anthropogenic and natural sources, though human activities are thought to contribute approximately 60 percent of the total.<\/p>\n<p>Overall, according to the new study, total methane emissions in the United States appear to be 1.5 times and 1.7 times higher than the amounts previously estimated by the <a href=\"http:\/\/epa.gov\/climatechange\/ghgemissions\/usinventoryreport.html\">U.S. Environmental Protection Agency<\/a> (EPA) and the international <a href=\"http:\/\/edgar.jrc.ec.europa.eu\/index.php\">Emissions Database for Global Atmospheric Research<\/a> (EDGAR), respectively.<\/p>\n<p>The difference lies in the methodology. The EPA and EDGAR use a bottom-up approach, calculating total emissions based on \u201cemissions factors\u201d \u2014 the amount of methane typically released per cow or per unit of coal or natural gas sold, for example. The new study takes a top-down approach, measuring what is actually present in the atmosphere and then using meteorological data and statistical analysis to trace it back to regional sources.<\/p>\n<p>Generated by a large, multi-institutional team of researchers, the latest findings offer a comprehensive baseline for assessing policies designed to reduce greenhouse gases. They also point to a few areas where the assumptions built into recent emissions factors and estimated totals may be flawed.<\/p>\n<p>\u201cThe bottom-up and top-down approaches give us very different answers about the level of methane gas emissions,\u201d notes lead author Scot M. Miller, a doctoral student in <a href=\"http:\/\/eps.harvard.edu\/\">Earth and Planetary Sciences<\/a> through the <a href=\"http:\/\/gsas.harvard.edu\/\">Harvard Graduate School of Arts and Sciences<\/a>. \u201cMost strikingly, our results are higher by a factor of 2.7 over the South Central United States, which we know is a key region for fossil-fuel extraction and refining. It will be important to resolve that discrepancy in order to fully understand the impact of these industries on methane emissions.\u201d<\/p>\n<blockquote><p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures.<\/p><\/blockquote>\n<p>Miller is a 2007 graduate of Harvard College and earned a master\u2019s degree in engineering sciences at the <a href=\"http:\/\/seas.harvard.edu\">Harvard School of Engineering and Applied Sciences<\/a> (SEAS) in 2013. He studies in the lab of <a href=\"http:\/\/www.seas.harvard.edu\/directory\/swofsy\">Steven C. Wofsy<\/a>, Abbott Lawrence Rotch Professor of Atmospheric and Environmental Science at SEAS.<\/p>\n<p>\u201cWhen we measure methane gas at the atmospheric level, we\u2019re seeing the cumulative effect of emissions that are happening at the surface across a very large region,\u201d says Wofsy, a co-author of the PNAS<i> <\/i>study. \u201cThat includes the sources that were part of the bottom-up inventories, but maybe also things they didn\u2019t think to measure.\u201d<\/p>\n<p>Miller and Wofsy, along with colleagues at the <a href=\"http:\/\/carnegiescience.edu\/\">Carnegie Institution for Science<\/a>, the <a href=\"http:\/\/www.noaa.gov\/\">National Oceanic and Atmospheric Administration<\/a> (NOAA), and five other institutions, used a combination of observation and modeling to conduct their analysis.<\/p>\n<p>NOAA and the U.S. Department of Energy collect observations of methane and other gases from the tops of telecommunications towers, typically about as tall as the Empire State Building, and during research flights. The team combined this data with meteorological models of the temperatures, winds, and movement of air masses from the same time period, and then used a statistical method known as geostatistical inverse modeling to essentially run the model backward and determine the methane\u2019s origin.<\/p>\n<p>The team also compared these results with regional economic and demographic data, as well as other information that provided clues to the sources \u2014 for example, data on human populations, livestock populations, electricity production from power plants, oil and natural gas production, production from oil refineries, rice production, and coal production. In addition, they drew correlations between methane levels and other gases that were observed at the time. For example, a high correlation between levels of methane and propane in the south-central region suggests a significant role for fossil fuels there.<\/p>\n<p>\u201cThis paper provides the most solid and the most detailed estimate to date of total U.S. methane emissions,\u201d says co-author <a href=\"http:\/\/dge.stanford.edu\/labs\/michalaklab\/index.html\">Anna M. Michalak<\/a>, a faculty member in the Department of Global Ecology at the Carnegie Institution for Science. Michalak is also an associate professor of environmental Earth system science at Stanford University. \u201cThis was really, from beginning to end, just a very clean analysis.\u201d<\/p>\n<p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures. It also encourages the formation of surface ozone in cities and affects other aspects of atmospheric chemistry.<\/p>\n<p>Seeking to establish a baseline against which to measure future change in methane emissions, the researchers compared observational data collected in 2007\u201308 with EDGAR and EPA data for the same year (using the revised EPA data for 2007\u201308 that was published in April 2013). Future studies will apply the same analysis to present-day data.<\/p>\n<p>\u201cThe beauty of the approach we\u2019re using is that, because we\u2019re taking measurements in the atmosphere, which carry with them a signature of everything that happened upwind, we get a very strong number on what that total should be,\u201d says Michalak. \u201cNow that we know the total does not equal the sum of the parts, that means that either some of those parts are not what we thought they were, or there are some parts that are simply missing from the inventories. It really offers an opportunity for governments to re-examine the inventories in light of what we now know.\u201d<\/p>\n<p>In addition to Miller, Wofsy, and Michalak, co-authors included <a href=\"http:\/\/aoss-research.engin.umich.edu\/faculty\/kort\/\">Eric A. Kort<\/a>, S.M. \u201905, Ph.D. \u201911, who is now a faculty member at the University of Michigan, Ann Arbor; Arlyn E. Andrews, Ph.D. \u201900, Edward J. Dlugokencky, and Stephen A. Montzka at NOAA\u2019s Earth System Research Laboratory; Sebastien C. Biraud and Marc L. Fischer at Lawrence Berkeley National Laboratory; Janusz Eluszkiewicz and Thomas Nehrkorn at Atmospheric and Environmental Research in Lexington, Mass.; Greet Janssens-Maenhout at the European Commission Joint Research Centre in Italy; and Ben R. Miller, John B. Miller, and Colm Sweeney at the University of Colorado Boulder.<\/p>\n"}],"innerHTML":"\n<div class=\"wp-block-group alignwide\">\n\n\n\n<\/div>\n","innerContent":["\n<div class=\"wp-block-group alignwide\">\n\n","\n\n<\/div>\n"],"rendered":"\n<div class=\"wp-block-group alignwide has-global-padding is-content-justification-center is-layout-constrained wp-block-group-is-layout-constrained\">\n\n\n\t\t<p>Emissions of methane from fossil fuel extraction and refining activities in the South Central United States are nearly five times higher than previous estimates, according to researchers at <a href=\"http:\/\/www.harvard.edu\/\">Harvard University<\/a> and seven other institutions. Their study, published this week in <a href=\"http:\/\/www.pnas.org\/\">Proceedings of the National Academy of Sciences (PNAS),<\/a> also suggests that the contribution from livestock operations may be twice as high as previously thought.<\/p>\n<p>Methane, a potent greenhouse gas, is produced through natural gas production and distribution, cattle farming, landfills, coal mining, manure management, and other anthropogenic and natural sources, though human activities are thought to contribute approximately 60 percent of the total.<\/p>\n<p>Overall, according to the new study, total methane emissions in the United States appear to be 1.5 times and 1.7 times higher than the amounts previously estimated by the <a href=\"http:\/\/epa.gov\/climatechange\/ghgemissions\/usinventoryreport.html\">U.S. Environmental Protection Agency<\/a> (EPA) and the international <a href=\"http:\/\/edgar.jrc.ec.europa.eu\/index.php\">Emissions Database for Global Atmospheric Research<\/a> (EDGAR), respectively.<\/p>\n<p>The difference lies in the methodology. The EPA and EDGAR use a bottom-up approach, calculating total emissions based on \u201cemissions factors\u201d \u2014 the amount of methane typically released per cow or per unit of coal or natural gas sold, for example. The new study takes a top-down approach, measuring what is actually present in the atmosphere and then using meteorological data and statistical analysis to trace it back to regional sources.<\/p>\n<p>Generated by a large, multi-institutional team of researchers, the latest findings offer a comprehensive baseline for assessing policies designed to reduce greenhouse gases. They also point to a few areas where the assumptions built into recent emissions factors and estimated totals may be flawed.<\/p>\n<p>\u201cThe bottom-up and top-down approaches give us very different answers about the level of methane gas emissions,\u201d notes lead author Scot M. Miller, a doctoral student in <a href=\"http:\/\/eps.harvard.edu\/\">Earth and Planetary Sciences<\/a> through the <a href=\"http:\/\/gsas.harvard.edu\/\">Harvard Graduate School of Arts and Sciences<\/a>. \u201cMost strikingly, our results are higher by a factor of 2.7 over the South Central United States, which we know is a key region for fossil-fuel extraction and refining. It will be important to resolve that discrepancy in order to fully understand the impact of these industries on methane emissions.\u201d<\/p>\n<blockquote><p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures.<\/p><\/blockquote>\n<p>Miller is a 2007 graduate of Harvard College and earned a master\u2019s degree in engineering sciences at the <a href=\"http:\/\/seas.harvard.edu\">Harvard School of Engineering and Applied Sciences<\/a> (SEAS) in 2013. He studies in the lab of <a href=\"http:\/\/www.seas.harvard.edu\/directory\/swofsy\">Steven C. Wofsy<\/a>, Abbott Lawrence Rotch Professor of Atmospheric and Environmental Science at SEAS.<\/p>\n<p>\u201cWhen we measure methane gas at the atmospheric level, we\u2019re seeing the cumulative effect of emissions that are happening at the surface across a very large region,\u201d says Wofsy, a co-author of the PNAS<i> <\/i>study. \u201cThat includes the sources that were part of the bottom-up inventories, but maybe also things they didn\u2019t think to measure.\u201d<\/p>\n<p>Miller and Wofsy, along with colleagues at the <a href=\"http:\/\/carnegiescience.edu\/\">Carnegie Institution for Science<\/a>, the <a href=\"http:\/\/www.noaa.gov\/\">National Oceanic and Atmospheric Administration<\/a> (NOAA), and five other institutions, used a combination of observation and modeling to conduct their analysis.<\/p>\n<p>NOAA and the U.S. Department of Energy collect observations of methane and other gases from the tops of telecommunications towers, typically about as tall as the Empire State Building, and during research flights. The team combined this data with meteorological models of the temperatures, winds, and movement of air masses from the same time period, and then used a statistical method known as geostatistical inverse modeling to essentially run the model backward and determine the methane\u2019s origin.<\/p>\n<p>The team also compared these results with regional economic and demographic data, as well as other information that provided clues to the sources \u2014 for example, data on human populations, livestock populations, electricity production from power plants, oil and natural gas production, production from oil refineries, rice production, and coal production. In addition, they drew correlations between methane levels and other gases that were observed at the time. For example, a high correlation between levels of methane and propane in the south-central region suggests a significant role for fossil fuels there.<\/p>\n<p>\u201cThis paper provides the most solid and the most detailed estimate to date of total U.S. methane emissions,\u201d says co-author <a href=\"http:\/\/dge.stanford.edu\/labs\/michalaklab\/index.html\">Anna M. Michalak<\/a>, a faculty member in the Department of Global Ecology at the Carnegie Institution for Science. Michalak is also an associate professor of environmental Earth system science at Stanford University. \u201cThis was really, from beginning to end, just a very clean analysis.\u201d<\/p>\n<p>Along with carbon dioxide, methane is one of the most important greenhouse gases in terms of its potential to raise global temperatures. It also encourages the formation of surface ozone in cities and affects other aspects of atmospheric chemistry.<\/p>\n<p>Seeking to establish a baseline against which to measure future change in methane emissions, the researchers compared observational data collected in 2007\u201308 with EDGAR and EPA data for the same year (using the revised EPA data for 2007\u201308 that was published in April 2013). Future studies will apply the same analysis to present-day data.<\/p>\n<p>\u201cThe beauty of the approach we\u2019re using is that, because we\u2019re taking measurements in the atmosphere, which carry with them a signature of everything that happened upwind, we get a very strong number on what that total should be,\u201d says Michalak. \u201cNow that we know the total does not equal the sum of the parts, that means that either some of those parts are not what we thought they were, or there are some parts that are simply missing from the inventories. It really offers an opportunity for governments to re-examine the inventories in light of what we now know.\u201d<\/p>\n<p>In addition to Miller, Wofsy, and Michalak, co-authors included <a href=\"http:\/\/aoss-research.engin.umich.edu\/faculty\/kort\/\">Eric A. Kort<\/a>, S.M. \u201905, Ph.D. \u201911, who is now a faculty member at the University of Michigan, Ann Arbor; Arlyn E. Andrews, Ph.D. \u201900, Edward J. Dlugokencky, and Stephen A. Montzka at NOAA\u2019s Earth System Research Laboratory; Sebastien C. Biraud and Marc L. Fischer at Lawrence Berkeley National Laboratory; Janusz Eluszkiewicz and Thomas Nehrkorn at Atmospheric and Environmental Research in Lexington, Mass.; Greet Janssens-Maenhout at the European Commission Joint Research Centre in Italy; and Ben R. Miller, John B. Miller, and Colm Sweeney at the University of Colorado Boulder.<\/p>\n\n\n<\/div>\n"}},"jetpack-related-posts":[{"id":333955,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2021\/10\/urban-areas-across-u-s-are-undercounting-greenhouse-gas-emissions\/","url_meta":{"origin":149974,"position":0},"title":"Leaky natural gas pipelines are tip of the iceberg","author":"harvardgazette","date":"October 26, 2021","format":false,"excerpt":"Methane emissions from the distribution and use of natural gas across U.S. cities are 2 to 10 times higher than recent estimates from the EPA.","rel":"","context":"In "Science & Tech"","block_context":{"text":"Science & Tech","link":"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/"},"img":{"alt_text":"Gas meters.","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2021\/10\/Meters2500.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2021\/10\/Meters2500.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2021\/10\/Meters2500.jpg?resize=525%2C300 1.5x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2021\/10\/Meters2500.jpg?resize=700%2C400 2x"},"classes":[]},{"id":355782,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2023\/03\/methane-tracking-satellite-may-be-fastest-way-to-slow-climate-change\/","url_meta":{"origin":149974,"position":1},"title":"Buying crucial time in climate change fight","author":"harvardgazette","date":"March 24, 2023","format":false,"excerpt":"Steven Wofsy explains how the satellite will spot global sources of methane emissions, which in many cases can be halted with relatively simple fixes.","rel":"","context":"In "Science & Tech"","block_context":{"text":"Science & Tech","link":"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/"},"img":{"alt_text":"Steve Wofsy,","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/03\/030223_Wofsy_016.jpeg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/03\/030223_Wofsy_016.jpeg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/03\/030223_Wofsy_016.jpeg?resize=525%2C300 1.5x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/03\/030223_Wofsy_016.jpeg?resize=700%2C400 2x"},"classes":[]},{"id":181824,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2016\/04\/hunting-polluting-gases-around-boston\/","url_meta":{"origin":149974,"position":2},"title":"Hunting polluting gases around Boston","author":"harvardgazette","date":"April 6, 2016","format":false,"excerpt":"Students, faculty, and fellows are fanning out across the Boston area to take measurements aimed at determining where and how much natural gas is leaking and where the worst carbon dioxide emissions occur.","rel":"","context":"In "Science & Tech"","block_context":{"text":"Science & Tech","link":"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/"},"img":{"alt_text":"","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2016\/04\/naturalgas605.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2016\/04\/naturalgas605.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2016\/04\/naturalgas605.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":354124,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2023\/02\/5-salata-institute-grants-to-accelerate-climate-action\/","url_meta":{"origin":149974,"position":3},"title":"Combining forces to accelerate climate action here, there, now","author":"gazettebeckycoleman","date":"February 13, 2023","format":false,"excerpt":"Experts from Harvard and around the world embark on ambitious interdisciplinary projects that tackle climate change challenges head-on.","rel":"","context":"In "Science & Tech"","block_context":{"text":"Science & Tech","link":"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/"},"img":{"alt_text":"Drought in India; flooding in Nigeria; Jeff Bezos announces climate pledge; flares burn off methane; coal miner.","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/02\/20230213_salata_research.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/02\/20230213_salata_research.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/02\/20230213_salata_research.jpg?resize=525%2C300 1.5x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2023\/02\/20230213_salata_research.jpg?resize=700%2C400 2x"},"classes":[]},{"id":165217,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2015\/01\/bostons-leaky-pipes-add-to-greenhouse-gas-buildup\/","url_meta":{"origin":149974,"position":4},"title":"Boston\u2019s leaky pipes add to greenhouse-gas buildup","author":"harvardgazette","date":"January 22, 2015","format":false,"excerpt":"A Harvard-led study reveals that an aging natural-gas distribution system short-changes Boston-area customers and contributes to greenhouse-gas buildup. Depending on the season, natural gas leaking from the local distribution system accounts for 60 percent to 100 percent of the region\u2019s emissions of methane.","rel":"","context":"In "Science & Tech"","block_context":{"text":"Science & Tech","link":"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/"},"img":{"alt_text":"","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2015\/01\/seas_pipes_courtesy-michael-krigsman-flickr-cc_605_1.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2015\/01\/seas_pipes_courtesy-michael-krigsman-flickr-cc_605_1.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2015\/01\/seas_pipes_courtesy-michael-krigsman-flickr-cc_605_1.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":351159,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2023\/04\/desire-to-battle-climate-change-rooted-in-childhood\/","url_meta":{"origin":149974,"position":5},"title":"Desire to battle climate change rooted in childhood","author":"harvardgazette","date":"April 12, 2023","format":false,"excerpt":"Environmental science and engineering doctoral student grew up next door to family\u2019s palm-oil refinery outside Bangkok.","rel":"","context":"In "Science & Tech"","block_context":{"text":"Science & Tech","link":"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/"},"img":{"alt_text":"Ju Chulakadabba.","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2022\/11\/110422_Chukakadabba_Ju_147.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2022\/11\/110422_Chukakadabba_Ju_147.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2022\/11\/110422_Chukakadabba_Ju_147.jpg?resize=525%2C300 1.5x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2022\/11\/110422_Chukakadabba_Ju_147.jpg?resize=700%2C400 2x"},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts\/149974","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/users\/105622744"}],"replies":[{"embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/comments?post=149974"}],"version-history":[{"count":1,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts\/149974\/revisions"}],"predecessor-version":[{"id":270974,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts\/149974\/revisions\/270974"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/media\/149976"}],"wp:attachment":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/media?parent=149974"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/categories?post=149974"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/tags?post=149974"},{"taxonomy":"format","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/gazette-formats?post=149974"},{"taxonomy":"series","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/series?post=149974"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}