The drive for fuel - p281

doi:10.1038/ngeo198

The production of clean energy for transportation makes demands on resources that are already scarce. Biofuels can contribute to a solution, but only to a limited extent.

Full Text - The drive for fuel | PDF (278 KB) - The drive for fuel

Rock clock synchronization - p282

Heiko Pälike & Frits Hilgen

doi:10.1038/ngeo197

Full Text - Rock clock synchronization | PDF (141 KB) - Rock clock synchronization

Thirst for energy - pp283 - 286

Carey W. King, Ashlynn S. Holman & Michael E. Webber

doi:10.1038/ngeo195

Power generation as well as the production of fuels for transportation requires water, and the supply of high-quality freshwater is energy intensive. A growing population and climate change will increase the pressure on both resources.

Full Text - Thirst for energy | PDF (259 KB) - Thirst for energy

Scottish craters, the Florida Current and more - p287

doi:10.1038/ngeo199

Full Text - Scottish craters, the Florida Current and more | PDF (220 KB) - Scottish craters, the Florida Current and more

Carbon cycle: Checking the thermostat - pp289 - 290

David Archer

doi:10.1038/ngeo194

Atmospheric carbon dioxide levels greatly influence the Earth's climate. Evidence from ice cores and marine sediments suggests that over timescales beyond the glacial cycles, carbon fluxes are finely balanced and act to stabilize temperatures.

Full Text - Carbon cycleChecking the thermostat | PDF (164 KB) - Carbon cycleChecking the thermostat

Subject Category: Climate science

See also: Letter by Zeebe & Caldeira

Geochemistry: Leftovers from core formation - pp290 - 291

Bernard Marty

doi:10.1038/ngeo193

Late addition of meteoric material to the Earth's mantle could explain the presence of iron-loving elements that should have entered the Earth's core at its formation. But experiments at realistic conditions show that enough palladium could have remained in the mantle.

Full Text - GeochemistryLeftovers from core formation | PDF (147 KB) - GeochemistryLeftovers from core formation

Subject Category: Geochemistry

See also: Letter by Righter et al.

Planetary science: Saturn's southern eye - p291

Heike Langenberg

doi:10.1038/ngeo188

Full Text - Planetary scienceSaturn's southern eye | PDF (98 KB) - Planetary scienceSaturn's southern eye

Subject Category: Planetary science

Atmospheric chemistry: Pollution meets sea salt - pp292 - 293

Roland von Glasow

doi:10.1038/ngeo192

In densely populated coastal areas, reactions of polluted air with sea salt aerosol from the ocean can lead to high surface ozone levels that affect air quality.

Full Text - Atmospheric chemistryPollution meets sea salt | PDF (181 KB) - Atmospheric chemistryPollution meets sea salt

Subject Category: Atmospheric science

Structural geology: Stressed rocks - p293

Ninad Bondre

doi:10.1038/ngeo190

Full Text - Structural geologyStressed rocks | PDF (139 KB) - Structural geologyStressed rocks

Subject Category: Structural geology, tectonics and geodynamics

Palaeoclimatology: A tale of two climates - pp294 - 295

Katharina Billups

doi:10.1038/ngeo191

The generally warm and ice-free conditions of the Eocene epoch rapidly declined to the cold and glaciated state of the Oligocene epoch. Geochemical evidence from deep-sea sediments resolves in detail the climatic events surrounding this transition.

Full Text - PalaeoclimatologyA tale of two climates | PDF (107 KB) - PalaeoclimatologyA tale of two climates

Subject Category: Palaeoclimate and palaeoceanography

See also: Article by Katz et al.

Seismology: Do faults shimmy before they shake? - pp295 - 296

Michael R. Brudzinski

doi:10.1038/ngeo196

Not only do plate boundary faults generate earthquakes, they also produce slow slip and non-volcanic tremor. New observations on these phenomena provide fresh insights into the conditions that dictate earthquake behaviour.

Full Text - SeismologyDo faults shimmy before they shake? | PDF (148 KB) - SeismologyDo faults shimmy before they shake?

Subject Category: Seismology

The role of subglacial water in ice-sheet mass balance - pp297 - 304

Robin E. Bell

doi:10.1038/ngeo186

Subglacial water can significantly affect the velocity of ice streams and outlet glaciers of ice sheets. Depending on the geometry and capacity of the subglacial hydrologic system, increased surface melting in Greenland over the coming decades may influence the ice sheet's mass balance. Furthermore, subglacial lakes in Antarctica can modulate ice velocities and act as nucleation points for new fast-flowing ice streams.

Abstract - | Full Text - The role of subglacial water in ice-sheet mass balance | PDF (1,219 KB) - The role of subglacial water in ice-sheet mass balance

Satellite measurements of the clear-sky greenhouse effect from tropospheric ozone - pp305 - 308

Helen M. Worden, Kevin W. Bowman, John R. Worden, Annmarie Eldering & Reinhard Beer

doi:10.1038/ngeo182

Tropospheric ozone contributes significantly to human-induced greenhouse warming. Calculations from satellite measurements of spectral radiance suggest that ozone in the upper troposphere caused an average reduction in clear-sky outgoing long-wave radiation over the oceans of 0.480.14 W m^{- 2} for the year 2006 between 45^° S and 45^° N.

First Paragraph - | Full Text - Satellite measurements of the clear-sky greenhouse effect from tropospheric ozone | PDF (1,533 KB) - Satellite measurements of the clear-sky greenhouse effect from tropospheric ozone | Supplementary information

Subject Categories: Atmospheric science | Climate science

Submarine groundwater discharge revealed by ²²⁸Ra distribution in the upper Atlantic Ocean - pp309 - 311

Willard S. Moore, Jorge L. Sarmiento & Robert M. Key

doi:10.1038/ngeo183

Submarine groundwater discharge, estimated from a ²²⁸Ra inventory across the upper Atlantic Ocean, provides a flux of 2–410¹³ m³ yr^{- 1}, equivalent to 80–160% of the influx from rivers into the Atlantic Ocean.

First Paragraph - | Full Text - Submarine groundwater discharge revealed by 228Ra distribution in the upper Atlantic Ocean | PDF (238 KB) - Submarine groundwater discharge revealed by 228Ra distribution in the upper Atlantic Ocean | Supplementary information

Subject Categories: Hydrology, hydrogeology and limnology | Oceanography

See also: related Backstory

Close mass balance of long-term carbon fluxes from ice-core CO₂ and ocean chemistry records - pp312 - 315

Richard E. Zeebe & Ken Caldeira

doi:10.1038/ngeo185

On geological timescales, carbon dioxide enters the atmosphere through volcanism and organic matter oxidation and is removed through mineral weathering and carbonate burial. An analysis of ice-core CO₂ records and marine carbonate chemistry indicates a tight coupling between these processes during the past 610,000 years, which suggests that a weathering feedback driven by atmospheric CO₂ leads to a mass balance between CO₂ sources and sinks on long timescales.

First Paragraph - | Full Text - Close mass balance of long-term carbon fluxes from ice-core CO2 and ocean chemistry records | PDF (355 KB) - Close mass balance of long-term carbon fluxes from ice-core CO2 and ocean chemistry records | Supplementary information

Subject Categories: Biogeochemistry | Geochemistry

Slow slip and frictional transition at low temperature at the Hikurangi subduction zone - pp316 - 320

Robert McCaffrey, Laura M. Wallace & John Beavan

doi:10.1038/ngeo178

Temperature changes with depth do not appear to be a primary control for either slow slip or fault-locking processes at the Hikurangi margin, North Island, New Zealand. Both slow-slip events and the geodetically observed transition from fault locking to free slip at depth occur at temperatures as low as 100 ^°C.

First Paragraph - | Full Text - Slow slip and frictional transition at low temperature at the Hikurangi subduction zone | PDF (2,966 KB) - Slow slip and frictional transition at low temperature at the Hikurangi subduction zone

Partitioning of palladium at high pressures and temperatures during core formation - pp321 - 323

K. Righter, M. Humayun & L. Danielson

doi:10.1038/ngeo180

Using experimental conditions approximating those of the early Earth, the partition coefficient for palladium was found to be sufficiently low to explain the palladium content of the Earth's mantle in terms of an early equilibration of the mantle with core-forming metals, rather than requiring the addition of a 'late veneer' of chondritic material after core formation.

First Paragraph - | Full Text - Partitioning of palladium at high pressures and temperatures during core formation | PDF (224 KB) - Partitioning of palladium at high pressures and temperatures during core formation | Supplementary information

Subject Categories: Geomagnetism, palaeomagnetism and core processes | Geochemistry

High levels of nitryl chloride in the polluted subtropical marine boundary layer - pp324 - 328

Hans D. Osthoff, James M. Roberts, A. R. Ravishankara, Eric J. Williams, Brian M. Lerner, Roberto Sommariva, Timothy S. Bates, Derek Coffman, Patricia K. Quinn, Jack E. Dibb, Harald Stark, James B. Burkholder, Ranajit K. Talukdar, James Meagher, Fred C. Fehsenfeld & Steven S. Brown

doi:10.1038/ngeo177

Nitryl chloride, an active halogen, can be produced through the night-time reaction of dinitrogen pentoxide with chloride-containing aerosol in the polluted marine boundary, and has been measured at levels that are sufficient to affect the photochemistry of oxidants off the southwestern US coast and near Houston, Texas.

Abstract - | Full Text - High levels of nitryl chloride in the polluted subtropical marine boundary layer | PDF (368 KB) - High levels of nitryl chloride in the polluted subtropical marine boundary layer | Supplementary information

Subject Category: Atmospheric science

See also: related Backstory

Stepwise transition from the Eocene greenhouse to the Oligocene icehouse - pp329 - 334

Miriam E. Katz, Kenneth G. Miller, James D. Wright, Bridget S. Wade, James V. Browning, Benjamin S. Cramer & Yair Rosenthal

doi:10.1038/ngeo179

The Eocene–Oligocene transition is the largest global cooling in the Cenozoic period. A comparison of three independent proxies from the continental shelf and deep ocean reveals a three-step transition to cold glacial conditions, with ice sheets 25% larger than their present size.

Abstract - | Full Text - Stepwise transition from the Eocene greenhouse to the Oligocene icehouse | PDF (338 KB) - Stepwise transition from the Eocene greenhouse to the Oligocene icehouse | Supplementary information

Subject Category: Palaeoclimate and palaeoceanography

The methane cycle on Titan - p335

Jonathan Lunine & Sushil Atreya

doi:10.1038/ngeo187

Full Text - The methane cycle on Titan | PDF (66 KB) - The methane cycle on Titan

Hunting for halogen chemistry - p338

doi:10.1038/ngeo184

Jim Roberts and colleagues inhaled petrochemical fumes and navigated between ships and oil platforms in order to understand halogen chemistry in the Houston area and along the Texas coast.

Full Text - Hunting for halogen chemistry | PDF (161 KB) - Hunting for halogen chemistry

Rooting for radium - pE9

doi:10.1038/ngeo189

Willard Moore and his colleagues collected 200-litre samples of sea water from depths of up to 1,000 metres and stirred up the odd octopus in order to determine the input of submarine groundwater discharge into the Atlantic Ocean.

Full Text - Rooting for radium | PDF (217 KB) - Rooting for radium