Time to celebrate - p1

doi:10.1038/ngeo409

Nature Geoscience is one year old. To mark the anniversary, a selection of our content will be freely accessible over the next three months.

Full Text - Time to celebrate | PDF (112 KB) - Time to celebrate

Carbon conveyor - p1

doi:10.1038/ngeo410

The oceans soak up a large fraction of the carbon dioxide we emit into the atmosphere. The long-term strength and efficiency of this carbon sink relies on the transport of surface waters to the deep ocean.

Full Text - Carbon conveyor | PDF (112 KB) - Carbon conveyor

Biochar is carbon negative - p2

Bruno Glaser, Mike Parr, Christelle Braun & Goodspeed Kopolo

doi:10.1038/ngeo395

Full Text - Biochar is carbon negative | PDF (54 KB) - Biochar is carbon negative

Searching out the sinks - pp3 - 4

Martin Heimann

doi:10.1038/ngeo405

Abstract - Searching out the sinks | Full Text - Searching out the sinks | PDF (273 KB) - Searching out the sinks

Our choice from the recent literature - p5

doi:10.1038/ngeo408

Full Text - Our choice from the recent literature | PDF (163 KB) - Our choice from the recent literature

Planetary Science: Mars's rotating shell - pp7 - 8

Francis Nimmo

doi:10.1038/ngeo401

Volcanism in the enormous Tharsis region on Mars migrated from south to north. Numerical modelling suggests that this migration as well as the current location of the region can be explained by net rotation of the lithosphere relative to the mantle.

Full Text - Planetary ScienceMars's rotating shell | PDF (231 KB) - Planetary ScienceMars's rotating shell

Subject Category: Planetary science

See also: Letter by Zhong

Astrobiology: Impacts and origins of life - pp8 - 9

André Brack

doi:10.1038/ngeo400

Meteorites frequently bombarded the surface of the early Earth. Could these impacts have provided the energy and materials to form the basic building blocks of life?

Full Text - AstrobiologyImpacts and origins of life | PDF (93 KB) - AstrobiologyImpacts and origins of life

Subject Category: Biogeochemistry

See also: Letter by Furukawa et al.

Geophysics: Going with the mantle flow - pp10 - 11

Maureen D. Long

doi:10.1038/ngeo398

Measurements of directional travel speed of seismic waves constrain flow in the upper mantle. Laboratory experiments suggest that high pressure can change the mantle's mineral alignment, leading to a 90° offset in the direction of the fastest seismic waves.

Full Text - GeophysicsGoing with the mantle flow | PDF (169 KB) - GeophysicsGoing with the mantle flow

Subject Categories: Seismology | Structural geology, tectonics and geodynamics

See also: Article by Jung et al.

Ocean science: Resetting the record - p11

Anna Armstrong

doi:10.1038/ngeo407

Full Text - Ocean scienceResetting the record | PDF (134 KB) - Ocean scienceResetting the record

Subject Category: Oceanography

Oceanography: Overturning assumptions - pp12 - 13

Susan Lozier

doi:10.1038/ngeo402

The lack of deep mixing in the subpolar North Atlantic Ocean for over a decade has raised concerns that climate warming may already be affecting the ocean circulation. A vigorous convection event last winter shows that the system holds some surprises yet.

Full Text - OceanographyOverturning assumptions | PDF (76 KB) - OceanographyOverturning assumptions

Subject Category: Oceanography

See also: Article by Våge et al.

Planetary science: Tidal flows in satellite oceans - pp13 - 14

Bruce G. Bills

doi:10.1038/ngeo396

Sub-surface oceans probably exist on several large satellites of Jupiter and Saturn. An analysis of Europa's tides suggests that some of the Rossby waves are resonantly enhanced by the obliquity, producing sufficient heat and flow to keep the ocean liquid.

Full Text - Planetary scienceTidal flows in satellite oceans | PDF (116 KB) - Planetary scienceTidal flows in satellite oceans

Atmospheric dynamics: The age of stratospheric air - pp14 - 16

Darryn Waugh

doi:10.1038/ngeo397

Climate models predict that increasing greenhouse gas levels will invigorate the circulation in the upper atmosphere. But a close look at observations of the age of stratospheric air over 30 years reveals no acceleration in the circulation.

Full Text - Atmospheric dynamicsThe age of stratospheric air | PDF (120 KB) - Atmospheric dynamicsThe age of stratospheric air

Subject Category: Atmospheric science

See also: Letter by Engel et al.

Sustaining coastal urban ecosystems - p16

Torbjörn E. Törnqvist & Douglas J. Meffert

doi:10.1038/ngeo399

Full Text - Sustaining coastal urban ecosystems | PDF (135 KB) - Sustaining coastal urban ecosystems

Climate Science: The other greenhouse effect - p16

Anna Armstrong

doi:10.1038/ngeo406

Full Text - Climate Science: The other greenhouse effect | PDF (137 KB) - Climate Science: The other greenhouse effect

Migration of Tharsis volcanism on Mars caused by differential rotation of the lithosphere - pp19 - 23

Shijie Zhong

doi:10.1038/ngeo392

As a single-plate planet, Mars cannot support large-scale motion of the lithosphere, according to the standard theory of stagnant-lid convection, but such motion is required to explain the position of the Tharsis Rise. Modelling work suggests that differential rotation of the lithosphere can resolve this problem.

First Paragraph - Migration of Tharsis volcanism on Mars caused by differential rotation of the lithosphere | Full Text - Migration of Tharsis volcanism on Mars caused by differential rotation of the lithosphere | PDF (1,214 KB) - Migration of Tharsis volcanism on Mars caused by differential rotation of the lithosphere | Supplementary information

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

See also: News and Views by Nimmo

Earth's ionospheric outflow dominated by hidden cold plasma - pp24 - 27

E. Engwall, A. I. Eriksson, C. M. Cully, M. André, R. Torbert & H. Vaith

doi:10.1038/ngeo387

The Earth constantly loses matter, mostly in the form of H⁺ and O⁺ ions. Analysis of measurements from the Cluster spacecraft reveals that the total loss of cold ions, below 1 eV in thermal energy, is larger than the previously observed, more energetic, outflow.

First Paragraph - Earth/'s ionospheric outflow dominated by hidden cold plasma | Full Text - Earth's ionospheric outflow dominated by hidden cold plasma | PDF (2,273 KB) - Earth's ionospheric outflow dominated by hidden cold plasma

Subject Category: Space physics

Age of stratospheric air unchanged within uncertainties over the past 30 years - pp28 - 31

A. Engel, T. Möbius, H. Bönisch, U. Schmidt, R. Heinz, I. Levin, E. Atlas, S. Aoki, T. Nakazawa, S. Sugawara, F. Moore, D. Hurst, J. Elkins, S. Schauffler, A. Andrews & K. Boering

doi:10.1038/ngeo388

The rising abundance of greenhouse gases in the atmosphere has been associated with a change in the stratospheric circulation and a decrease in the mean age of stratospheric air. Balloon-borne measurements of trace gases over 30 years suggest that, in contrast to model predictions, there have been no significant trends (at a 90% confidence limit) in the age of stratospheric air.

First Paragraph - Age of stratospheric air unchanged within uncertainties over the past 30[thinsp]years | Full Text - Age of stratospheric air unchanged within uncertainties over the past 30 years | PDF (2,865 KB) - Age of stratospheric air unchanged within uncertainties over the past 30 years | Supplementary information

Subject Categories: Atmospheric science | Climate science

See also: News and Views by Waugh

The role of the stratosphere in the European climate response to El Niño - pp32 - 36

S. Ineson & A. A. Scaife

doi:10.1038/ngeo381

Observational studies show a clear response in European climate to El Niño/Southern Oscillation in late winter. Simulations with an atmospheric general circulation model identify a long-distance pathway connecting climate variability in the Pacific region and Europe via the stratosphere, the upper layer of the atmosphere.

First Paragraph - The role of the stratosphere in the European climate response to El Nino | Full Text - The role of the stratosphere in the European climate response to El Niño | PDF (6,215 KB) - The role of the stratosphere in the European climate response to El Niño

Effects of agricultural land use on the composition of fluvial dissolved organic matter - pp37 - 41

Henry F. Wilson & Marguerite A. Xenopoulos

doi:10.1038/ngeo391

Nearly 40% of the Earth's ice-free surface area is cropland or pasture. Measurements of dissolved organic matter along a gradient of agricultural land use suggest that agricultural watersheds contain less complex, more microbially derived dissolved organic matter than natural wetlands.

First Paragraph - Effects of agricultural land use on the composition of fluvial dissolved organic matter | Full Text - Effects of agricultural land use on the composition of fluvial dissolved organic matter | PDF (4,443 KB) - Effects of agricultural land use on the composition of fluvial dissolved organic matter | Supplementary information

Molybdenum limitation of asymbiotic nitrogen fixation in tropical forest soils - pp42 - 45

Alexander R. Barron, Nina Wurzburger, Jean Phillipe Bellenger, S. Joseph Wright, Anne M. L. Kraepiel & Lars O. Hedin

doi:10.1038/ngeo366

Biological nitrogen fixation limits plant growth and carbon exchange at local to global scales. Long-term nutrient manipulation experiments in forests and short-term manipulation experiments in microcosms suggest that the micronutrient molybdenum, a component of the nitrogen-fixing enzyme nitrogenase, limits nitrogen fixation by asymbiotic bacteria in tropical soils in Panama.

First Paragraph - Molybdenum limitation of asymbiotic nitrogen fixation in tropical forest soils | Full Text - Molybdenum limitation of asymbiotic nitrogen fixation in tropical forest soils | PDF (530 KB) - Molybdenum limitation of asymbiotic nitrogen fixation in tropical forest soils

Unprecedented recent warming of surface temperatures in the eastern tropical Pacific Ocean - pp46 - 50

Jessica L. Conroy, Alejandra Restrepo, Jonathan T. Overpeck, Miriam Steinitz-Kannan, Julia E. Cole, Mark B. Bush & Paul A. Colinvaux

doi:10.1038/ngeo390

Climate variability in the tropical Pacific Ocean influences climate across much of the planet. A diatom-based record of sea surface temperatures from El Junco lake, Galapagos, reveals that the most recent half-century is the warmest 50-year period in the past 1,200 years.

First Paragraph - Unprecedented recent warming of surface temperatures in the eastern tropical Pacific Ocean | Full Text - Unprecedented recent warming of surface temperatures in the eastern tropical Pacific Ocean | PDF (3,261 KB) - Unprecedented recent warming of surface temperatures in the eastern tropical Pacific Ocean | Supplementary information

Subject Categories: Palaeoclimate and palaeoceanography | Climate science

See also: related Backstory

The impact of volcanic forcing on tropical temperatures during the past four centuries - pp51 - 56

Rosanne D'Arrigo, Rob Wilson & Alexander Tudhope

doi:10.1038/ngeo393

The effect of volcanism on low-latitude climate has been difficult to quantify. A compilation of tropical and subtropical annually resolved climate reconstructions shows a correlation between low sea surface temperatures and low-latitude volcanic activity over the past four centuries.

First Paragraph - The impact of volcanic forcing on tropical temperatures during the past four centuries | Full Text - The impact of volcanic forcing on tropical temperatures during the past four centuries | PDF (2,192 KB) - The impact of volcanic forcing on tropical temperatures during the past four centuries | Supplementary information

Global mass wasting at continental margins during Ordovician high meteorite influx - pp57 - 61

John Parnell

doi:10.1038/ngeo386

The break-up of an asteroid led to the rapid delivery of meteorites to Earth around 470 million years ago. The widespread occurrence of sedimentary megabreccias deposited at the same time suggests this high influx of meteorites could have triggered mass wasting — downslope movement of rock and sediment — at continental margins, by inducing the destabilization of sedimentary slopes.

First Paragraph - Global mass wasting at continental margins during Ordovician high meteorite influx | Full Text - Global mass wasting at continental margins during Ordovician high meteorite influx | PDF (648 KB) - Global mass wasting at continental margins during Ordovician high meteorite influx | Supplementary information

Biomolecule formation by oceanic impacts on early Earth - pp62 - 66

Yoshihiro Furukawa, Toshimori Sekine, Masahiro Oba, Takeshi Kakegawa & Hiromoto Nakazawa

doi:10.1038/ngeo383

Impacts of extraterrestrial objects were frequent on the early Earth. Shock experiments suggest that the impact of the most common type of meteorites into sea water could have synthesized the organic molecules that served as the building blocks of life.

First Paragraph - Biomolecule formation by oceanic impacts on early Earth | Full Text - Biomolecule formation by oceanic impacts on early Earth | PDF (1,073 KB) - Biomolecule formation by oceanic impacts on early Earth | Supplementary information

Subject Category: Geochemistry

See also: related Backstory | News and Views by Brack

Surprising return of deep convection to the subpolar North Atlantic Ocean in winter 2007–2008 - pp67 - 72

Kjetil Våge, Robert S. Pickart, Virginie Thierry, Gilles Reverdin, Craig M. Lee, Brian Petrie, Tom A. Agnew, Amy Wong & Mads H. Ribergaard

doi:10.1038/ngeo382

Deep convection in the subpolar North Atlantic, an important component of the global ocean circulation, has been absent in recent years. Profiling float data from the Argo programme document the return of deep mixing to the subpolar gyre in both the Labrador and Irminger seas in the winter of 2007–2008.

Abstract - Surprising return of deep convection to the subpolar North Atlantic Ocean in winter 2007-2008 | Full Text - Surprising return of deep convection to the subpolar North Atlantic Ocean in winter 2007–2008 | PDF (17,713 KB) - Surprising return of deep convection to the subpolar North Atlantic Ocean in winter 2007–2008

Subject Categories: Oceanography | Climate science

See also: News and Views by Lozier

Upper mantle seismic anisotropy resulting from pressure-induced slip transition in olivine - pp73 - 77

Haemyeong Jung, Won Mo & Harry W. Green

doi:10.1038/ngeo389

Seismic anisotropy in Earth's oceanic lithosphere and in the mantle wedge above subduction zones is associated with crystallographic preferred orientations of olivine. Experiments at high pressure and temperature suggest that a pressure of 3 GPa can induce the same changes in the crystal structure of olivine as high water activity at lower pressures.

Abstract - Upper mantle seismic anisotropy resulting from pressure-induced slip transition in olivine | Full Text - Upper mantle seismic anisotropy resulting from pressure-induced slip transition in olivine | PDF (1,168 KB) - Upper mantle seismic anisotropy resulting from pressure-induced slip transition in olivine | Supplementary information

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

See also: News and Views by Long

Gallivanting around the Galápagos - p80

doi:10.1038/ngeo404

Jessica Conroy and colleagues braved mud and rain and got nipped by sea lions in an attempt to unravel the record of tropical Pacific climate change.

Full Text - Gallivanting around the Galápagos | PDF (243 KB) - Gallivanting around the Galápagos

See also: Letter by Conroy et al.

Making molecules - pE1

doi:10.1038/ngeo403

Yoshihiro Furukawa and colleagues stuck to their guns in an attempt to recreate life on the early Earth.

Full Text - Making molecules | PDF (391 KB) - Making molecules

See also: Letter by Furukawa et al.