Nature Geoscience contents: April 2013 Volume 6 Number 4 pp241-320

TABLE OF CONTENTS April 2013 Volume 6, Issue 4 Editorial Correspondence In the press Research Highlights News and Views Correction Letters Articles Subscribe   Facebook   RSS   Recommend to library   Twitter   Advertisement Nature Geoscience - subscribe today! Ensure you have access to articles in Nature Geoscience, subscribe today. Each month, your personal subscription will provide you with content covering all aspects of Earth and planetary sciences.   Editorial Top Message in a bottle   p241 doi:10.1038/ngeo1798 The oceans have long accumulated the waste products of civilization. Dumping at sea is banned, but to protect the marine environment we must also monitor litter on coastal lands and rivers. Correspondence Top Test of a decadal climate forecast   pp243 - 244 Myles R. Allen, John F. B. Mitchell & Peter A. Stott doi:10.1038/ngeo1788 In the press Top Double trouble from space   p245 Nicola Jones doi:10.1038/ngeo1784 Research Highlights Top Hydrogeology: Mantle vents | Planetary science: Churning Mercury | Biogeochemistry: Deep-sea carbon fix | Atmospheric chemistry: Early oxidation News and Views Top Tectonics: Mantle spread across the sea floor   pp247 - 248 Deborah Smith doi:10.1038/ngeo1786 The sea floor around mid-ocean ridges is often carpeted by hummocky lava flows. Images from the Southwest Indian Ridge sea floor, however, show a smooth texture created by exhumation and widespread exposure of altered mantle rocks. See also: Article by Sauter et al. Economic geology: Gilded by earthquakes   pp248 - 250 Dave Craw doi:10.1038/ngeo1775 Gold is often deposited in Earth's crust by fluids that percolate through rock fractures. Earthquakes cause rock fractures to expand rapidly and could cause the fluids to evaporate, triggering almost instantaneous gold deposition. See also: Letter by Weatherley & Henley Oceanography: Rise from below   p250 Alicia Newton doi:10.1038/ngeo1790 Biogeochemistry: Rusty meltwaters   pp251 - 252 Rob Raiswell doi:10.1038/ngeo1776 Iron limits plankton productivity in large regions of the global ocean. Analyses of meltwater from the Greenland ice sheet suggests that subglacial weathering delivers significant quantities of biologically available iron to the North Atlantic Ocean. See also: Letter by Bhatia et al. Ocean ecology: Life in an oceanic extreme   pp252 - 253 Eric Epping doi:10.1038/ngeo1785 Scarce food supplies could hinder biological activity in the ocean's depths. However, measurements at Mariana Trench point to an unexpectedly active microbial community in the deepest seafloor setting on the planet. See also: Letter by Glud et al. Geoscience JOBS of the week Lecturer / Senior Lecturer / Reader in Stable Isotope Geoscience University of Glasgow Research Fellow in Physical Oceanography (Dynamics of the Ocean Surface Boundary Level) National Oceanography Centre Southampton Maersk Oil Chair in Applied Geophysics The Department of Geoscience, Aarhus University Tenure Track Researcher Tokai University Institute of Innovative Science and Tcchnology Assistant Professor Massachusetts Institute of Technology (MIT) More Science jobs from Geoscience EVENT 13th International Multidisciplinary Scientific GeoConference & EXPO SGEM2013 16.-22.06.13 Albena, Bulgaria More science events from Correction Top Abandoned frontier   p253 doi:10.1038/ngeo1777 Letters Top A chaotic long-lived vortex at the southern pole of Venus   pp254 - 257 I. Garate-Lopez, R. Hueso, A. Sánchez-Lavega, J. Peralta, G. Piccioni & P. Drossart doi:10.1038/ngeo1764 A whirling vortex has been observed in the atmosphere at the south pole of Venus. Cloud motions tracked by the Venus Express spacecraft suggest that the south polar vortex is long-lived, erratic and baroclinic in character. Little net clear-sky radiative forcing from recent regional redistribution of aerosols   pp258 - 262 D. M. Murphy doi:10.1038/ngeo1740 Aerosols scatter and absorb incoming solar radiation, with consequences for the energy balance of the atmosphere. An analysis of satellite data suggests that the regional redistribution of aerosols over the past decade had little net effect on the global radiative forcing of the atmosphere. Increase in the range between wet and dry season precipitation   pp263 - 267 Chia Chou, John C. H. Chiang, Chia-Wei Lan, Chia-Hui Chung, Yi-Chun Liao & Chia-Jung Lee doi:10.1038/ngeo1744 The water vapour content of the atmosphere has increased as a result of global warming, strengthening the hydrological cycle. An analysis of observational data suggests that wet seasons have become wetter, and dry seasons drier, in recent decades. Simulated resilience of tropical rainforests to CO2-induced climate change   pp268 - 273 Chris Huntingford, Przemyslaw Zelazowski, David Galbraith, Lina M. Mercado, Stephen Sitch, Rosie Fisher, Mark Lomas, Anthony P. Walker, Chris D. Jones, Ben B. B. Booth, Yadvinder Malhi, Debbie Hemming, Gillian Kay, Peter Good, Simon L. Lewis, Oliver L. Phillips, Owen K. Atkin, Jon Lloyd, Emanuel Gloor, Joana Zaragoza-Castells, Patrick Meir, Richard Betts, Phil P. Harris, Carlos Nobre, Jose Marengo & Peter M. Cox doi:10.1038/ngeo1741 Assessing potential future carbon loss from tropical forests is important for evaluating the efficacy of programmes for reducing emissions from deforestation and degradation (REDD). An exploration of results from 22 climate models in conjunction with a land surface scheme suggests that in the Americas, Africa and Asia, the resilience of tropical forests to climate change is higher than expected, although uncertainties are large. Greenland meltwater as a significant and potentially bioavailable source of iron to the ocean   pp274 - 278 Maya P. Bhatia, Elizabeth B. Kujawinski, Sarah B. Das, Crystaline F. Breier, Paul B. Henderson & Matthew A. Charette doi:10.1038/ngeo1746 The micronutrient iron is thought to limit primary production in large regions of the global ocean. Meltwater measurements suggest that the Greenland ice sheet serves as a significant source of potentially bioavailable iron to the surrounding coastal ocean See also: News and Views by Raiswell Strong latitudinal patterns in the elemental ratios of marine plankton and organic matter   pp279 - 283 Adam C. Martiny, Chau T. A. Pham, Francois W. Primeau, Jasper A. Vrugt, J. Keith Moore, Simon A. Levin & Michael W. Lomas doi:10.1038/ngeo1757 The elemental composition of marine organic matter is used to infer a variety of oceanic ecosystem processes. A compilation of observational data suggests that elemental ratios differ substantially from the Redfield ratio, but exhibit a clear latitudinal trend. High rates of microbial carbon turnover in sediments in the deepest oceanic trench on Earth   pp284 - 288 Ronnie N. Glud, Frank Wenzhöfer, Mathias Middelboe, Kazumasa Oguri, Robert Turnewitsch, Donald E. Canfield & Hiroshi Kitazato doi:10.1038/ngeo1773 Microbes regulate the decomposition of organic matter in marine sediments. Measurements at the deepest oceanic site on Earth reveal high rates of microbial activity, potentially fuelled by the deposition of organic matter. See also: News and Views by Epping Synchronization of the climate system to eccentricity forcing and the 100,000-year problem   pp289 - 293 José A. Rial, Jeseung Oh & Elizabeth Reischmann doi:10.1038/ngeo1756 The 100,000-year problem refers to an apparent mismatch between the strength of solar forcing associated with the 100,000-year cycle of eccentricity in the Earth's orbit and the amplitude of glacial–interglacial cycles. Numerical analyses suggest that recent glacial–interglacial cycles can instead be explained by a phase locking between internal climate oscillations and the 413,000-year eccentricity cycle. Flash vaporization during earthquakes evidenced by gold deposits   pp294 - 298 Dion K. Weatherley & Richard W. Henley doi:10.1038/ngeo1759 Fluids flowing through cavities in Earth's crust can deposit gold. Thermo-mechanical modelling of a fluid-filled cavity that expands suddenly during an earthquake shows that the drop in pressure would cause the fluid to vaporize and deposit the gold almost instantaneously. See also: News and Views by Craw The long precursory phase of most large interplate earthquakes   pp299 - 302 Michel Bouchon, Virginie Durand, David Marsan, Hayrullah Karabulut & Jean Schmittbuhl doi:10.1038/ngeo1770 Foreshocks precede some—but not all—earthquakes. Analysis of all earthquakes larger than magnitude 6.5 that occurred between 1999 and 2011 shows that earthquakes at plate boundaries are often preceded by increasing foreshock activity in the days leading up to the quake, whereas earthquakes in plate interiors often are not. Articles Top High-velocity collisions from the lunar cataclysm recorded in asteroidal meteorites   pp303 - 307 S. Marchi, W. F. Bottke, B. A. Cohen, K. Wünnemann, D. A. Kring, H. Y. McSween, M. C. De Sanctis, D. P. O'Brien, P. Schenk, C. A. Raymond & C. T. Russell doi:10.1038/ngeo1769 Lunar samples suggest that the inner Solar System was bombarded by asteroids about 4 Gyr ago. Radiometric ages of meteorites suggest an unusual number of high-velocity asteroids at this time, consistent with a dynamical origin of the bombardment in which the asteroids were pushed by outer planet migration onto highly eccentric orbits. Isotopic ratios of nitrite as tracers of the sources and age of oceanic nitrite   pp308 - 313 Carolyn Buchwald & Karen L. Casciotti doi:10.1038/ngeo1745 Nitrite, a central intermediate in the marine nitrogen cycle, accumulates at the base of the sunlit surface ocean. Isotopic measurements suggest that ammonia oxidation is the primary source of nitrite in the primary nitrite maximum in the Arabian Sea. Continuous exhumation of mantle-derived rocks at the Southwest Indian Ridge for 11 million years   pp314 - 320 Daniel Sauter, Mathilde Cannat, Stéphane Rouméjon, Muriel Andreani, Dominique Birot, Adrien Bronner, Daniele Brunelli, Julie Carlut, Adélie Delacour, Vivien Guyader, Christopher J. MacLeod, Gianreto Manatschal, Véronique Mendel, Bénédicte Ménez, Valerio Pasini, Etienne Ruellan & Roger Searle doi:10.1038/ngeo1771 The sea floor at the easternmost Southwest Indian mid-ocean ridge is smooth, unlike that at other mid-ocean ridges. Sonar imaging and analysis of rock samples show that the sea floor here is composed almost entirely of sea-water-altered mantle rocks that have been brought to the surface by large faults on both sides of the ridge axis over the past 11 million years. See also: News and Views by Smith Top Advertisement Nature Geoscience: call for papers The Nature Geoscience Editorial team is now accepting manuscripts from researchers who are active at the frontiers of this diverse and multidisciplinary field. Articles for Nature Geoscience will be selected and edited to have the maximum appeal to the global geosciences community. Manuscripts should be submitted through the online submission system The complete Guide for Authors can be viewed online   Natureevents is a fully searchable, multi-disciplinary database designed to maximise exposure for events organisers. The contents of the Natureevents Directory are now live. The digital version is available here. Find the latest scientific conferences, courses, meetings and symposia on natureevents.com. For event advertising opportunities across the Nature Publishing Group portfolio please contact natureevents@nature.com More Nature Events

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