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1 September 2015 Project Update Volume 96, Issue 16

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1 September 2015 Project Update Volume 96, Issue 16 VOL. 96 NO. 16 1 SEPT 2015 Weird Tresses of Ice Future of Climate Research South Asian Earth & Space Science News Geomagnetic Data Hub Save Money the Right Way Act now to save on registration and housing. Housing and Early Registration Deadline: 12 November 11:59 P.M. EST To get the best rates, join or renew your AGU membership by 14 October fallmeeting.agu.org Earth & Space Science News Contents 1 SEPTEMBER 2015 PROJECT UPDATE VOLUME 96, ISSUE 16 19 Making the Northern Indian Ocean a Hub of Geomagnetic Data A new initiative seeks to unite and network the magnetic research community in the northern Indian Ocean region. MEETING REPORT Modeling the Stratosphere’s 8 “Heartbeat” RESEARCH SPOTLIGHT 12 COVER 23 Small Rivers Could Have Big Impact Past Phosphorus Runoff Causes on Arctic Ocean Present Oxygen Depletion in Lakes The Mackenzie River carries the bulk of freshwater flow from North Sediment cores show how phosphorus America’s tundra to the North Atlantic. But what about the effects of pollution in the 1950s led to current, smaller rivers from Canada’s Arctic islands? inherited hypoxia in lakes in the Alps. 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 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 Earth’s Deep Interior Michael Poland, Geodesy Michael N. Gooseff, Hydrology Eric M. Riggs, Education 3 Kristine C. Harper, History Adrian Tuck, Nonlinear Geophysics of Geophysics Sergio Vinciguerra, Mineral Keith D. Koper, Seismology and Rock Physics Robert E. Kopp, Geomagnetism Earle Williams, Atmospheric 9–11 Opinion and Paleomagnetism and Space Electricity John W. Lane, Near-Surface Mary Lou Zoback, Societal Impacts Future Directions for the World Geophysics and Policy Sciences Climate Research Programme. Staff Production: Faith A. Ishii, Production Manager; Melissa A. Tribur, Senior Production Specialist; Liz Castenson, Editor’s Assistant; Yael Fitzpatrick, Manager, Design and 23–25 Research Spotlight Branding; Valerie Bassett and Travis Frazier, Electronic Graphics Specialists Past Phosphorus Runoff Causes Editorial: Peter L. Weiss, Manager/Senior News Editor; Mohi Kumar, Science Writer/ Editor; Randy Showstack, Senior News Writer; JoAnna Wendel, Writer Present Oxygen Depletion in Marketing: Angelo Bouselli and Mirelle Moscovitch, Marketing Analysts Lakes; Rethinking How Tropical Advertising: Christy Hanson, Manager; Tel: +1-202-777-7536; Email: advertising@ Convection Works; What Climate agu.org Information Is Most Useful for ©2015. American Geophysical Union. All Rights Reserved. Material in this issue may Predicting Floods?; How Did the be photocopied by individual scientists for research or classroom use. Permission Moon Get Its Shape? is also granted to use short quotes, figures, and tables for publication in scientific 25 books and journals. For permission for any other uses, contact the AGU Publications Office. 26–31 Positions Available Eos (ISSN 0096-3941) is published semi-monthly, on the 1st and 15th of the month 3–6 News except the 1st of January 2015 by the American Geophysical Union, 2000 Florida Current job openings in the Earth Ave., NW, Washington, DC 20009, USA. Periodical Class postage paid at Washington, Fungus, Physics Explain Weird and space sciences. D. C., and at additional mailing offices. POSTMASTER: Send address changes to Member Service Center, 2000 Florida Ave., NW, Washington, DC 20009, USA. Tresses of Ice; Leading Companies Member Service Center: 8:00 a.m.–6:00 p.m. Eastern time; Tel: +1-202-462-6900; Take White House Climate Pledge; 32 Postcards from the Field Fax: +1-202-328-0566; Tel. orders in U.S.: 1-800-966-2481; Email: [email protected]. Comet Lander Makes a Hard Use AGU’s Geophysical Electronic Manuscript Submissions system to submit a Discovery; Hearing Sparks Concerns Harvesting snow algae from the manuscript: http://eos-submit.agu.org. About Planetary Science Funding. surface of Collier Glacier in Oregon. Views expressed in this publication do not necessarily reflect official positions of the American Geophysical Union unless expressly stated. Christine W. McEntee, Executive Director/CEO 7–8 Meeting Reports On the Cover The Future of Antarctic Subglacial A view of the Kellett River on Lake Exploration; Modeling the Canada’s Banks Island. Stratosphere’s “Heartbeat.” Credit: Robie W. Macdonald. facebook.com/AmericanGeophysicalUnion @AGU_Eos linkedin.com/company/american-geophysical-union youtube.com/user/AGUvideos 2 // Eos 1 September 2015 NEWS hypotheses about how hair ice forms posed by Fungus, Physics other scientists who, since Wegener, also investigated the curious filaments. The growth Explain Weird Tresses of Ice of hair ice filaments can be seen in a time- lapse video (http://bit.ly/IceGrowVideo) taken at the Gletschergarten (Glacier Garden) in Lucerne, Switzerland. ix years after Alfred Wegener published Fungus Found Unlike the spiky ice crystal crusts called his theory on continental drift, the geo- Hair ice grows under conditions of freezing rime ice and hoarfrost, which grow under con- S physicist scrutinized another curious temperature and high humidity. From 2012 ditions similar to those of hair ice but with relationship, one so obscure, however, that it until last year, the researchers created these new crystals added at their tips, hair ice grows would take almost a century to confirm his conditions from time to time in a garden shed as its name implies: with the newest crystals hypothesis. to conduct hair ice–growing experiments. forming at its roots, near the wood. During the winter of 1916–1917 in the The researchers credit the elaborate ice It’s there that a film of water gets trapped Vosges Mountains near the French- German coiffures subsequently created to Exidiopsis between wood and ice in such a way that ice border, he noticed tufts of ultrafine, effusa, from the phylum Basidiomycota. It is hairs sprout radially from the wood surface, 4- centimeter- long strands of ice sprouting among 11 different species of fungi that biolo- like spokes of a wheel, the researchers report. from dead branches. The first scientist to gist Gisela Preuß, a secondary school teacher Suction forces within the film draw water from investigate the hair ice phenomenon, Wege- in Neustadt, Germany, and coauthor on the within the pores of the wood toward the freez- ner reported the next year a likely relationship report, found from microscopic examination ing front, maintaining the sandwiched water between the projecting ice strands and fungus of hair ice–growing wood. film while adding new crystals to the hairs. filaments that also caught his eye, clinging to “Exidiopsis effusa colonized all of our hair Most known observations of hair ice have the surface of the hair ice–bearing wood. Yet ice– producing wood, and in more than half of come from broadleaf forests, largely located how the two were connected remained a mys- the samples, it was the only species present,” between 45°N and 55°N latitude, in regions tery—until now. she said. including Scotland, Ireland, Wales, the Neth- This summer, a team of German and Swiss In the tests, killing Exidiopsis effusa with erlands, Sweden, Slovenia, Russia, the U.S. scientists not only identified the fungus hot water prevented new hair ice from Pacific Northwest, and Canada’s west coast. behind these exotic ice structures but also developing when favorable hair ice condi- have explained how an interplay among bio- tions were restored. Also, in the absence of Fungal Freeze Control logical factors, atmospheric conditions, and the fungus, ice formed only a simple crust on With or without fungal activity, “the same basic properties of liquid and frozen water the wood. amount of ice is produced on wood,” said may lead to the delicate tresses of hair ice. study coauthor Christian Mätzler, an emeritus The researchers published their findings on Ice Hairs Sprout Out professor of physics at the University of Bern 22 July in Biogeosciences (http://bit.ly/ The new tests also tracked temperature varia- in Switzerland, in a press release. Although EGUBiogeo), a journal of the European Geo- tions and chemical composition of water and the fungus is a key player in sculpting hair ice, sciences Union. ice during hair ice growth. They confirmed the resulting fibers do not encapsulate any fungus filaments. Rather, the fungus remains on the wood as white webby films. Instead of acting as a scaffolding for ice fibers, the fungus appears to foster hair ice growth by secreting a chemical that prevents small ice crystals from reconfiguring into larger ones—a process known as recrystallization. “The action of the fungus is to enable the ice to form thin hairs—with a diameter of about 0.01 millimeter—and to keep this shape over many hours at temperatures close to 0°C,” explained Mätzler. “Our hypothesis 0) includes that the hairs are stabilized by a recrystallization inhibitor that is provided by the fungus.” This inhibitor, likely a protein, prevents damage that recrystallization would wreak on structures that are fine grained, such as hair ice filaments.
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    wood, aided by the presence of the Exidiopsis The Outside Story effusa fungus. Scientists believe that as the fungus breaks down the wood of a broad-leafed tree species, it produces complex molecules that mix with the water in the stem. Moisture near the surface of the dead branch or log is extruded from the pores of the wood and freezes into thin hairs of ice, which build up overnight into what looks like a tuft of wool or a white, shiny beard. Frost flowers are similar, but occur on the stems of certain plants. They may resemble white ribbon candy, flowing curtains, swanlike sculptures, serpentine swirls, silky spirals, or glossy fans. Despite the name, they’re not flowers, nor frost. While true frost occurs when moisture in the air condenses on a cold surface, these fanciful shapes result when sap, augmented by water drawn up from the roots, slowly pushes through the stem of an herbaceous plant and freezes on contact with the cold. They form most often near the base of the stem, but may extend further up. Hair Ice and Frost Flowers: Frost flowers occur so infrequently that many Ephemeral Frozen Forms woods walkers never see them. Their rarity is By: Laurie D. Morrissey largely due to the limited circumstances that create them. The ground must be warm enough If you are out walking on an early winter morning, for the plant’s root system to be active and the air you might be lucky enough to see some of nature’s must be cold enough to freeze the water flowing most beautiful and ephemeral sights: hair ice and up its conductive tissues.
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