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SEA ICE EXTENT Connect to AGU’S Network of Earth and Space Science Blogs VOL. 96 NO. 12 1 JUL 2015 Slip Magnitude Along Thrust Faults Student Travel Grant Earth & Space Science News Challenge PREDICTING SEA ICE EXTENT Connect to AGU’s network of Earth and space science blogs Do you have a science blog and would like it to be hosted by AGU? Contact AGU at [email protected]. blogs.agu.org Earth & Space Science News Contents 1 JULY 2015 PROJECT UPDATE VOLUME 96, ISSUE 12 Dispelling Clouds 16of Uncertainty How do you build a climate model that accounts for cloud physics and the transitions between cloud regimes? Use MAGIC. NEWS 6 Experiment Captures First Image of Thunder Scientists can now visually capture the sound waves created by thunder, a technique that could lead to an increased understanding of how lightning forms and transmits energy. RESEARCH SPOTLIGHT Please place LeBeon_ JB010794.tiff 10 COVER 24 Surface Folds Hint at Magnitude Improving Predictions of Arctic of Slip Along Thrust Faults Sea Ice Extent The shape of deformed sediments at the surface may allow researchers to estimate Scientists in the Sea Ice Prediction Network share and discuss their the cumulative slip along thrust faults such user-oriented​­ forecasts of seasonal sea ice in a changing Arctic. as the Chelungpu fault in Taiwan. Earth & Space Science News Eos.org // 1 Contents DEPARTMENTS Editor in Chief Barbara T. Richman: AGU, Washington, D. C., USA; eos_ [email protected] Editors Christina M. S. Cohen Wendy S. Gordon Carol A. Stein California Institute Ecologia Consulting, Department of Earth and of Technology, Pasadena, Austin, Texas, USA; Environmental Sciences, Calif., USA; wendy@ecologiaconsulting University of Illinois at cohen@srl .caltech.edu .com Chicago, Chicago, Ill., USA; [email protected] José D. Fuentes David Halpern Department of Meteorology, Jet Propulsion Laboratory, Pennsylvania State Pasadena, Calif., USA; University, University davidhalpern29@gmail Park, Pa., USA; .com [email protected] Editorial Advisory Board M. Lee Allison, Earth and Space Xin-Zhong Liang, Global Science Informatics Environmental Change Lora S. Armstrong, Volcanology, Jian Lin, Tectonophysics Geochemistry, and Petrology Figen Mekik, Paleoceanography Michael A. Ellis, Earth and Planetary and Paleoclimatology Surface Processes Jerry L. Miller, Ocean Sciences Arlene M. Fiore, Atmospheric Sciences Michael A. Mischna, Planetary 25 Nicola J. Fox, Space Physics Sciences and Aeronomy Thomas H. Painter, Cryosphere Steve Frolking, Biogeosciences Sciences Edward J. Garnero, Study of the Roger A. Pielke Sr., Natural Hazards 24–28 Research Spotlight Earth’s Deep Interior Michael Poland, Geodesy Michael N. Gooseff, Hydrology Eric M. Riggs, Education Surface Folds Hint at Magnitude Kristine C. Harper, History Adrian Tuck, Nonlinear Geophysics of Slip Along Thrust Faults; Global of Geophysics Sergio Vinciguerra, Mineral Keith D. Koper, Seismology and Rock Physics Atmospheric Model Simulates Robert E. Kopp, Geomagnetism Earle Williams, Atmospheric Fine Details of Gravity Waves; and Paleomagnetism and Space Electricity John W. Lane, Near-Surface Mary Lou Zoback, Societal Impacts Dynamics of the Earth’s Surface in Geophysics and Policy Sciences the Eastern Tibetan Plateau; What Staff Causes Extreme Hail, Tornadoes, Production: Faith A. Ishii, Production Manager; Melissa A. Tribur, Senior Production and Floods in South America?; New Specialist; Liz Castenson, Editor’s Assistant; Yael Fitzpatrick, Manager, Design and 21 Insights into Currents in Earth’s Branding; Valerie Bassett and Travis Frazier, Electronic Graphics Specialists Magnetic Field; Inflexibility of Some Editorial: Peter L. Weiss, Manager/Senior News Editor; Randy Showstack, Senior Writer; Mohi Kumar, Science Writer/Editor; JoAnna Wendel, Writer Hydrological Models Limits Accuracy; Marketing: Angelo Bouselli and Mirelle Moscovitch, Marketing Analysts 3–8 News Hacking a Climate Satellite to See Advertising: Christy Hanson, Manager; Tel: +1-202-777-7536; Email: advertising@ Beneath the Ocean’s Surface; Historic agu.org Global Warming “Hiatus” Never Warm Periods Shed Light on Future ©2015. American Geophysical Union. All Rights Reserved. Material in this issue may Happened, Study Says; Building Cyclones. be photocopied by individual scientists for research or classroom use. Permission a Better Glacial Speedometer; is also granted to use short quotes, figures, and tables for publication in scientific Experiment Captures First Image books and journals. For permission for any other uses, contact the AGU Publications Office. of Thunder; Obama Links Climate 29–31 Positions Available Eos (ISSN 0096-3941) is published semi-monthly, on the 1st and 15th of the month Change to National and Global Current job openings in the Earth except the 1st of January 2015 by the American Geophysical Union, 2000 Florida Security. and space sciences. Ave., NW, Washington, DC 20009, USA. Periodical Class postage paid at Washington, D. C., and at additional mailing offices. POSTMASTER: Send address changes to Member Service Center, 2000 Florida Ave., NW, Washington, DC 20009, USA. 9 Meeting Report 32 Postcards from the Field Member Service Center: 8:00 a.m.–6:00 p.m. Eastern time; Tel: +1-202-462-6900; Fax: +1-202-328-0566; Tel. orders in U.S.: 1-800-966-2481; Email: [email protected]. Communicating Uncertainties in A photo from a perch on some Hiko Use AGU’s Geophysical Electronic Manuscript Submissions system to submit a Sea Surface Temperature. Tuff boulders in the Pahroc Range in manuscript: http://eos-submit.agu.org. Nevada. Views expressed in this publication do not necessarily reflect official positions of the 21–23 AGU News American Geophysical Union unless expressly stated. Christine W. McEntee, Executive Director/CEO AGU’s 2015 Mass Media Fellow to On the Cover Report for National Geographic; Take Scientists study Arctic sea ice and the Student Travel Grant Challenge; melt ponds in the Chukchi Sea. What’s New in the AGU Blogosphere. Credit: NASA/Kathryn Hansen facebook.com/AmericanGeophysicalUnion @AGU_Eos linkedin.com/company/american-geophysical-union youtube.com/user/AGUvideos 2 // Eos 1 July 2015 NEWS global surface temperature analysis to exam- Global Warming “Hiatus” ine how sea surface temperatures (SSTs) were being measured. Scientists measure SSTs in Never Happened, Study Says several ways—by collecting ocean water in a bucket and measuring its temperature directly, measuring the temperature of water taken in by a ship’s engine as a coolant, or using floating buoys moored at locations scat- tered around the planet’s oceans. Each technique records slightly different temperatures in the same region, so scientists have to adjust the data. In the past couple of decades, the number of buoys has increased, Karl explained, adding coverage to 15% more of the ocean. Because buoys tend to read colder temperatures than do ships in the same places, Karl and his team corrected for this bias by adding 0.12°C to each buoy measure- ment. By combining the ocean data with improved calculations of air temperatures over land around the world, Karl and his colleagues found that overall global surface warming during 2000–2014 was 0.116°C per decade, more than twice the estimated 0.039°C per decade, starting in 1998, that IPCC had reported. Further, having reexamined global temperatures as far back as 1880, Karl and his team found that from 1950 to 1999, the rate of warming was 0.113°C per decade. “The [new] data still show somewhat slower warming post-2000 than in the preceding NOAA/CREWS decades, but the difference is no longer statis- The number of buoys measuring sea surface temperatures has increased in recent decades. Their readings tend to tically significant, which means it is no longer be lower than those taken by ships at a given location. For these reasons and others, a team of scientists has adjusted justifiable to say that there was a ‘hiatus,’” data sets to provide a more accurate measurement of average global temperature. said Steven Sherwood, director of the Climate Change Research Centre at the University of presumed pause in the rise of Earth’s Measurement Bias South Wales, Australia. He was not involved in average global surface temperature To measure how Earth’s average global tem- the study. A might never have happened, accord- perature is changing, scientists combine hun- “The fact that such small changes to the ing to new research published in early June in dreds of thousands of measurements from analysis make the difference between a hiatus Science. Earth’s surface, taken by land instruments, or not merely underlines how fragile a concept The apparent hiatus, first reported by the ships, buoys, and orbiting satellites. Scientists [the hiatus] was in the first place,” said Gavin Intergovernmental Panel on Climate Change must comb through these data to eliminate Schmidt, director of NASA’s Goddard Institute (IPCC) in 2013, instead resulted from a shift random errors and correct for differences in for Space Studies in New York City. during the past couple of decades to greater how each type of instrument measures tem- use of buoys for measuring sea surface tem- perature. Faux Pause? peratures. Buoys tend to give cooler readings Since the IPCC report came out, scientists than measurements taken from ships, have been investigating what was causing the explained Thomas Karl, director of the Global warming over the supposed hiatus. Some studies found evidence National Centers for Environmental Informa- past 15 years is the that the leveling of global temperature rise tion of the National Oceanic and Atmospheric resulted from absorption of the “missing” Administration (NOAA) and lead author on the strongest it’s been since heat by the world’s oceans. research paper. Uncorrected, those discrepan- Other research indicated that although cies led to the apparent slowdown since 1998 the latter half of the 20th there was no pause in global temperature rise, in the long-​­observed rise of Earth’s average century. there might have been a temporary slowdown surface temperature. of warming for the Northern Hemisphere. “The biggest takeaway is that there is no Michael Mann, director of the Earth System slowdown in global warming,” Karl said.
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