Complex communication - p371

doi:10.1038/ngeo545

In the world of Web 2.0, the variety of channels for communicating science is exploding. Technology can help to generate images that attract attention, but there is much more to reaching the public than pretty pictures.

Full Text - Complex communication | PDF (197 KB) - Complex communication

Unexpected rise in extreme precipitation caused by a shift in rain type? - pp372 - 373

J. O. Haerter & P. Berg

doi:10.1038/ngeo523

Full Text - Unexpected rise in extreme precipitation caused by a shift in rain type? | PDF (137 KB) - Unexpected rise in extreme precipitation caused by a shift in rain type? | Supplementary information

See also: Correspondence by Lenderink & van Meijgaard

Unexpected rise in extreme precipitation caused by a shift in rain type? - p373

Geert Lenderink & Erik van Meijgaard

doi:10.1038/ngeo524

Full Text - Unexpected rise in extreme precipitation caused by a shift in rain type? | PDF (89 KB) - Unexpected rise in extreme precipitation caused by a shift in rain type?

See also: Correspondence by Haerter & Berg

Securing the legacy of the IPY - pp374 - 376

Bob Dickson

doi:10.1038/ngeo538

Paradoxically, as the International Polar Year ends we enter its most important phase. Now we must decide — and quickly — which mix of observations to sustain, based on what we have learnt.

Full Text - Securing the legacy of the IPY | PDF (387 KB) - Securing the legacy of the IPY

Tales from Antarctica - p377

doi:10.1038/ngeo540

Anna Armstrong reviews Encounters at the End of the World by Werner Herzog, Discovery Films: 2007. UK release date: 24 April 2009.

Full Text - Tales from Antarctica | PDF (136 KB) - Tales from Antarctica

Our choice from the recent literature - p378

doi:10.1038/ngeo543

Full Text - Our choice from the recent literature | PDF (153 KB) - Our choice from the recent literature

Geophysics: Tectonics in the Earth's core - pp379 - 380

Peter Olson

doi:10.1038/ngeo534

The complex three-dimensional structure of the Earth's solid inner core reveals how it has grown through time. Numerical simulations of the solidification process suggest that part of this structure has resulted from recent tectonic activity.

Full Text - GeophysicsTectonics in the Earth's core | PDF (257 KB) - GeophysicsTectonics in the Earth's core

Subject Categories: Geomagnetism, palaeomagnetism and core processes | Structural geology, tectonics and geodynamics

See also: Letter by Deguen & Cardin

Palaeoclimate: Delayed Holocene warming - pp380 - 381

Martin Widmann

doi:10.1038/ngeo536

Remnants of the Laurentide ice sheet lasted until about 7,000 years ago. Climate simulations show that they caused the multimillennial delay between maximum early Holocene solar radiation and temperatures evident in Northern Hemisphere proxy records.

Full Text - PalaeoclimateDelayed Holocene warming | PDF (258 KB) - PalaeoclimateDelayed Holocene warming

Subject Category: Palaeoclimate and palaeoceanography

See also: Letter by Renssen et al.

Tectonics: Draining Nevada - pp381 - 382

Vera Schulte-Pelkum

doi:10.1038/ngeo532

The lack of strong splitting of seismic shear waves below central Nevada is in marked contrast to the surrounding region. Seismic data and numerical experiments suggest that a skinny, cylindrical drip of lithosphere may be to blame.

Full Text - TectonicsDraining Nevada | PDF (129 KB) - TectonicsDraining Nevada

Subject Category: Structural geology, tectonics and geodynamics

See also: Article by West et al.

Environmental science: Rising arsenic risk? - pp383 - 384

David Polya & Laurent Charlet

doi:10.1038/ngeo537

Millions of people in southern Asia rely on arsenic-contaminated groundwater to live. Massive water withdrawals through wells may be increasing the problem by drawing arsenic-mobilizing substances into shallow aquifers and arsenic-contaminated shallow groundwaters into deeper aquifers.

Full Text - Environmental scienceRising arsenic risk? | PDF (286 KB) - Environmental scienceRising arsenic risk?

Palaeontology: Aging well - p384

Alicia Newton

doi:10.1038/ngeo541

Full Text - PalaeontologyAging well | PDF (123 KB) - PalaeontologyAging well

Atmospheric science: Biological ice formation - pp385 - 386

Corinna Hoose

doi:10.1038/ngeo530

Ice clouds significantly affect the Earth's radiative forcing, but which particles lie at the core of the ice crystals is a matter of debate. In-flight spectroscopy suggests that biogenic materials contribute to ice formation in clouds.

Full Text - Atmospheric scienceBiological ice formation | PDF (211 KB) - Atmospheric scienceBiological ice formation

Subject Category: Atmospheric science

See also: Letter by Pratt et al.

Palaeontology: Extinction before the snowball - pp386 - 387

Frank A. Corsetti

doi:10.1038/ngeo533

A widespread biotic turnover occurred around the time of the Sturtian glaciation. Microfossil analyses show that one regional extinction pre-dates the glacial advance, challenging the more severe models for glacial effects in the Neoproterozoic era.

Full Text - PalaeontologyExtinction before the snowball | PDF (222 KB) - PalaeontologyExtinction before the snowball

Subject Category: Palaeontology

See also: Letter by Nagy et al.

Atmospheric pollution: Brief relief - p387

Anna Armstrong

doi:10.1038/ngeo542

Full Text - Atmospheric pollutionBrief relief | PDF (167 KB) - Atmospheric pollutionBrief relief

Volcanism in the Solar System - pp389 - 397

Lionel Wilson

doi:10.1038/ngeo529

The myriad bodies that occur in the Solar System show a wide range of physical properties. Exploration by spacecraft during the past four decades has shown that volcanism — a major mechanism by which internal heat is transported to the surface — is common on many of these bodies.

Abstract - Volcanism in the Solar System | Full Text - Volcanism in the Solar System | PDF (837 KB) - Volcanism in the Solar System

Subject Categories: Planetary science | Volcanology, mineralogy and petrology

In situ detection of biological particles in cloud ice-crystals - pp398 - 401

Kerri A. Pratt, Paul J. DeMott, Jeffrey R. French, Zhien Wang, Douglas L. Westphal, Andrew J. Heymsfield, Cynthia H. Twohy, Anthony J. Prenni & Kimberly A. Prather

doi:10.1038/ngeo521

The impact of aerosol particles on the formation and properties of clouds is one of the largest remaining sources of uncertainty in climate change projections. Now, aircraft-aerosol time-of-flight spectroscopy measurements of ice residues indicate that biological particles trigger ice formation in high-altitude clouds.

First Paragraph - In situ: detection of biological particles in cloud ice-crystals | Full Text - In situ detection of biological particles in cloud ice-crystals | PDF (693 KB) - In situ detection of biological particles in cloud ice-crystals | Supplementary information

Subject Category: Atmospheric science

See also: related Backstory | News and Views by Hoose

Relative roles of biogenic emissions and Saharan dust as ice nuclei in the Amazon basin - pp402 - 405

Anthony J. Prenni, Markus D. Petters, Sonia M. Kreidenweis, Colette L. Heald, Scot T. Martin, Paulo Artaxo, Rebecca M. Garland, Adam G. Wollny & Ulrich Pöschl

doi:10.1038/ngeo517

Some aerosol particles—known as ice nuclei—initiate ice formation in clouds, thereby influencing precipitation, cloud dynamics and incoming and outgoing solar radiation. Measurements of the concentration and elemental composition of ice nuclei in the Amazon basin indicate that local bioparticles and Saharan dust could explain the presence of almost all ice nuclei during the wet season.

First Paragraph - Relative roles of biogenic emissions and Saharan dust as ice nuclei in the Amazon basin | Full Text - Relative roles of biogenic emissions and Saharan dust as ice nuclei in the Amazon basin | PDF (512 KB) - Relative roles of biogenic emissions and Saharan dust as ice nuclei in the Amazon basin

Subject Categories: Atmospheric science | Biogeochemistry

See also: News and Views by Hoose

Observed sources and variability of Nordic seas overflow - pp406 - 410

Tor Eldevik, Jan Even Ø. Nilsen, Doroteaciro Iovino, K. Anders Olsson, Anne Britt Sandø & Helge Drange

doi:10.1038/ngeo518

The overflows from the Nordic seas maintain the deep branch of the North Atlantic circulation that is an important part of the global climate system. An analysis of observed ocean temperatures and salinities between 1950 and 2005 shows that the Atlantic water circulating in the Nordic seas is the main source for change in the overflow waters.

First Paragraph - Observed sources and variability of Nordic seas overflow | Full Text - Observed sources and variability of Nordic seas overflow | PDF (1,005 KB) - Observed sources and variability of Nordic seas overflow

Subject Categories: Climate science | Oceanography

The spatial and temporal complexity of the Holocene thermal maximum - pp411 - 414

H. Renssen, H. Seppä, O. Heiri, D. M. Roche, H. Goosse & T. Fichefet

doi:10.1038/ngeo513

The period of relatively warm climate from 11,000 to 5,000 years ago was marked by considerable temporal and spatial variability. Model simulations relate this complexity to the influence of the waning Laurentide ice sheet.

First Paragraph - The spatial and temporal complexity of the Holocene thermal maximum | Full Text - The spatial and temporal complexity of the Holocene thermal maximum | PDF (5,419 KB) - The spatial and temporal complexity of the Holocene thermal maximum | Supplementary information

Subject Category: Palaeoclimate and palaeoceanography

See also: News and Views by Widmann

Biotic turnover driven by eutrophication before the Sturtian low-latitude glaciation - pp415 - 418

Robin M. Nagy, Susannah M. Porter, Carol M. Dehler & Yanan Shen

doi:10.1038/ngeo525

A dramatic oceanic biotic shift from eukaryotic phytoplankton to bacteria occurred about 740 million years ago. Microfossil and geochemical data from the Chuar Group in the southwestern United States link this biotic turnover to widespread eutrophication of surface waters.

First Paragraph - Biotic turnover driven by eutrophication before the Sturtian low-latitude glaciation | Full Text - Biotic turnover driven by eutrophication before the Sturtian low-latitude glaciation | PDF (1,408 KB) - Biotic turnover driven by eutrophication before the Sturtian low-latitude glaciation | Supplementary information

Subject Categories: Palaeoclimate and palaeoceanography | Palaeontology

See also: related Backstory | News and Views by Corsetti

Tectonic history of the Earth's inner core preserved in its seismic structure - pp419 - 422

Renaud Deguen & Philippe Cardin

doi:10.1038/ngeo522

Seismic data show that the Earth's inner core is structurally complex. Numerical simulations suggest that whereas the deeper structure may be inherited from past episodes of inner-core growth, the origin of the shallow structure is due to ongoing deformation.

First Paragraph - Tectonic history of the Earth/'s inner core preserved in its seismic structure | Full Text - Tectonic history of the Earth's inner core preserved in its seismic structure | PDF (722 KB) - Tectonic history of the Earth's inner core preserved in its seismic structure | Supplementary information

Subject Categories: Geomagnetism, palaeomagnetism and core processes | Seismology

See also: News and Views by Olson

Structural reactivation in plate tectonics controlled by olivine crystal anisotropy - pp423 - 427

Andréa Tommasi, Mickael Knoll, Alain Vauchez, Javier W. Signorelli, Catherine Thoraval & Roland Logé

doi:10.1038/ngeo528

Structures formed during ancient tectonic events are commonly reactivated during subsequent tectonism. Numerical models point to mechanical anisotropy arising from the inherited orientation of crystals of the mineral olivine in the lithospheric mantle as the cause of this behaviour.

First Paragraph - Structural reactivation in plate tectonics controlled by olivine crystal anisotropy | Full Text - Structural reactivation in plate tectonics controlled by olivine crystal anisotropy | PDF (2,176 KB) - Structural reactivation in plate tectonics controlled by olivine crystal anisotropy | Supplementary information

Subject Categories: Structural geology, tectonics and geodynamics | Volcanology, mineralogy and petrology

Oceanic forcing of the Marine Isotope Stage 11 interglacial - pp428 - 433

Alexander J. Dickson, Christopher J. Beer, Ciara Dempsey, Mark A. Maslin, James A. Bendle, Erin L. McClymont & Richard D. Pancost

doi:10.1038/ngeo527

The interglacial period that occurred about 400,000 years ago—Marine Isotope Stage 11—was the longest out of the past five glacial cycles. A proxy-based alignment of this interglacial with the Holocene, and a subsequent analysis of carbon isotopic data from marine sediments, indicates that the unusual length may have been driven by strong poleward oceanic heat transport.

Abstract - Oceanic forcing of the Marine Isotope Stage 11 interglacial | Full Text - Oceanic forcing of the Marine Isotope Stage 11 interglacial | PDF (1,040 KB) - Oceanic forcing of the Marine Isotope Stage 11 interglacial | Supplementary information

Subject Category: Palaeoclimate and palaeoceanography

Mid-Pliocene climate change amplified by a switch in Indonesian subsurface throughflow - pp434 - 438

Cyrus Karas, Dirk Nürnberg, Anil K. Gupta, Ralf Tiedemann, Kuppusamy Mohan & Torsten Bickert

doi:10.1038/ngeo520

Tectonic activity severely restricted the seaway connecting the tropical Pacific and Indian oceans sometime between about 3 and 4 million years ago. Ocean temperature and salinity reconstructions indicate that the Indonesian Gateway reached its present configuration about 2.95 million years ago, leading to the cooling and freshening of subsurface water in the tropical eastern Indian Ocean.

Abstract - Mid-Pliocene climate change amplified by a switch in Indonesian subsurface throughflow | Full Text - Mid-Pliocene climate change amplified by a switch in Indonesian subsurface throughflow | PDF (899 KB) - Mid-Pliocene climate change amplified by a switch in Indonesian subsurface throughflow | Supplementary information

Subject Category: Palaeoclimate and palaeoceanography

Vertical mantle flow associated with a lithospheric drip beneath the Great Basin - pp439 - 444

John D. West, Matthew J. Fouch, Jeffrey B. Roth & Linda T. Elkins-Tanton

doi:10.1038/ngeo526

Seismic anisotropy data for the Great Basin region of the western United States, coupled with tomographic images, help delineate a northeast-dipping lithospheric drip. Numerical experiments suggest that the drip could have formed owing to gravitational instability triggered by a density increase of about 1% and a temperature increase of about 10%.

Abstract - Vertical mantle flow associated with a lithospheric drip beneath the Great Basin | Full Text - Vertical mantle flow associated with a lithospheric drip beneath the Great Basin | PDF (11,530 KB) - Vertical mantle flow associated with a lithospheric drip beneath the Great Basin | Supplementary information

Subject Categories: Seismology | Structural geology, tectonics and geodynamics

See also: related Backstory | News and Views by Schulte-Pelkum

Print version of the May issue - p444

doi:10.1038/ngeo548

Full Text - Print version of the May issue | PDF (196 KB) - Print version of the May issue

A hidden drip - p446

doi:10.1038/ngeo539

John West and colleagues struggled with widely held misconceptions and computer hackers in their attempt to explain mantle processes beneath the Great Basin in the United States.

Full Text - A hidden drip | PDF (161 KB) - A hidden drip

See also: Article by West et al.

Chasing clouds - pE9

doi:10.1038/ngeo531

Kerri Pratt and colleagues stayed calm under pressure and made friends with 'Shirley' as they flew through the clouds over Wyoming.

Full Text - Chasing clouds | PDF (156 KB) - Chasing clouds

See also: Letter by Pratt et al.

Capsizing in canyons - pE10

doi:10.1038/ngeo535

Susannah Porter, Carol Dehler and colleagues hiked miles in burning heat and braved unforgiving river rapids to sample rocks in the Grand Canyon.

Full Text - Capsizing in canyons | PDF (193 KB) - Capsizing in canyons

See also: Letter by Nagy et al.