News & Views in 2013

Rainfall disparities are expected to intensify in response to anthropogenic climate change. Model simulations suggest that wet regions and seasons will get wetter, and that a warmer equator will get wetter too.

Snow and ice influence the climate and chemistry of the polar atmosphere. Field experiments in Alaska point to the significance of surface snow for polar ozone depletion events.

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.

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.

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.

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.

The evolution of Earth's largest hidden landscape beneath the East Antarctic Ice Sheet is poorly understood. Analyses of offshore sediments confirm that the ice incised deep troughs that host fast-flowing ice streams today, while older landscape features have been preserved.

The Palaeocene–Eocene Thermal Maximum was marked by global warming and ocean acidification. Fossil and experimental analyses show that different species of marine calcifying algae responded very differently to the environmental upheavals.

Where continents break apart, new ocean basins are formed. The discovery of ancient continental minerals on a young, volcanic island suggests that parts of the Indian Ocean floor may be underlain by fragments of a long-lost continent.

The presence of water in lunar volcanic rocks has been attributed to delivery after the Moon formed. Water detected in rocks from the ancient lunar highlands suggests that the Moon already contained water early in its history, and poses more challenges for the giant impact theory of Moon formation.

Antarctic Bottom Water is formed along the fringes of Antarctica and fills much of the abyssal oceans. Data from moored instruments and tagged marine mammals confirm an unexpected site of bottom water formation at Cape Darnley, west of the Amery Ice Shelf.

Oxygen minimum zones crop up along the eastern boundaries of ocean basins in the low latitudes. A survey of the oxygen minimum zone in the eastern South Pacific points to the coastal zone as a hotspot for anammox-driven marine nitrogen loss.

About 8,200 years ago, the overturning circulation in the Atlantic Ocean slowed and the Northern Hemisphere cooled. A speleothem record from China reveals a period of drying that occurred almost simultaneously with the cooling recorded by the Greenland ice cores.

The molten-iron alloy of the core meets the mantle's silicate rock at Earth's core–mantle boundary. Seismological images reveal hummocks of iron-enriched material above the boundary, highlighting the heterogeneous nature of the mantle.

The Antarctic Peninsula has long been thought to be the only part of Antarctica that has warmed in recent decades. Careful detective work confirms that West Antarctica is also warming rapidly.

At the end of the Eocene epoch, permanent ice cover developed over Antarctica as the Earth began to cool from greenhouse warmth. Sediment records off the Antarctic coast show spikes in weathering rate at the onset of ice growth that may indicate synchronous consumption of atmospheric carbon dioxide.