Volume 5 Issue 11, November 2012

River regulation and sea-level rise have damaged deltaic ecosystems as well as the sedimentological processes that support them. More scientific effort needs to be directed towards restoring land-building processes in our vanishing deltas.

In 2011, a modest earthquake in southern Spain seriously damaged the city of Lorca. Analysis of surface deformation suggests that the quake was caused by rupture of a shallow fault patch brought closer to failure by the pumping of water from a nearby aquifer.

Reconstructing past climate in the Southern Hemisphere is a challenge. An analysis of tree-ring records suggests that recent changes in the southern storm track in summer are unprecedented in the past 600 years.

The surface of the Moon is not totally devoid of water. Analyses of lunar soils reveal that impact glasses contain significant amounts of water, with an isotopic composition that is indicative of an origin from the solar wind.

Subtropical highs influence climate over extensive regions of the planet. These maritime high-pressure systems are set to intensify in boreal summer over the coming century, as a result of an increase in the land–sea thermal contrast.

Glacial ice covers around 10% of the Earth's continents. A review of the literature suggests that microbes living on glaciers and ice sheets are an integral part of both the glacial environment and the Earth's ecosystem.

The nearside and farside of the Moon are compositionally distinct. The detection of low-calcium pyroxene around large impact basins suggests that the huge Procellarum basin on the nearside may be an ancient impact structure and a relic scar of the violent collision that produced the lunar dichotomy.

Over the past few years, it has become clear that the Moon’s surface is not entirely dry. The direct identification of hydroxyl in glasses produced in lunar soils by the impact of micrometeorites supports the idea that water was delivered to the lunar surface by the solar wind.

Stratospheric circulation is known to affect weather in the troposphere. Climate modelling reveals a connection between variations in the stratospheric and North Atlantic ocean circulation over the past 30 years, and demonstrates that the stratosphere is an important component of climate over multidecadal timescales.

The Atlantic Ocean has been suggested as an important driver of variability in European climate on decadal timescales. Analyses of ocean and atmosphere temperature data from observations suggest that the shift in European climate during the 1990s was a result of warming in the North Atlantic Ocean.

Recent changes in the Southern Annular Mode are associated with warmer, drier conditions in the Southern Hemisphere. An analysis of tree-ring records there suggests that these changes have significantly altered tree growth.

Marine ice streams whose beds deepen inland are thought to be inherently unstable. Numerical modelling of the Maguerite Bay ice-stream retreat in West Antarctica since the Last Glacial Maximum suggests that an ice stream can stabilize on an inland-sloping bed owing to increased lateral drag where the ice stream narrows.

In spring 2011, a record-breaking flood necessitated diversion of water from the lower Mississippi River to the Atchafalaya River Basin. A comparison between the dynamics in the two basins based on field-calibrated satellite observations and in situ data suggests that river-mouth dynamics and wetland sedimentation are directly linked.

The North Atlantic Oscillation influences climate in the Arctic region and northern Europe. Reconstructions of circulation patterns associated with the North Atlantic Oscillation from a 5,200-year-long lake sediment record suggest that the atmospheric circulation responded to significant transitions in Northern Hemisphere climate.

During the Last Glacial Maximum, the pattern of Atlantic Meridional Overturning Circulation was different from today. A combination of sediment chemistry and a scavenging model suggests that the glacial circulation was shallower and at least as vigorous as today.

The last glacial period was marked by rapid reorganizations of oceanic and atmospheric circulation. Speleothem records from the Amazon Basin suggest that precipitation variability was linked to these events.

Earthquake rupture is influenced by stress conditions in the crust before the quake. Analysis and modelling of surface deformation caused by the May 2011 earthquake in Lorca, Spain, indicate that groundwater extraction influenced the pattern of fault rupture.

Over the past decade, Kīlauea and Mauna Loa—adjacent volcanoes in Hawai‘i—have inflated and deflated in tandem, yet their shallow volcanic plumbing systems are separate. Numerical modelling of the volcanoes shows that dynamic stress transfer by asthenospheric pore pressure is a viable mechanism for volcano coupling in Hawai‘i.

Subtropical high-pressure systems influence atmospheric circulation and global climate. Model simulations and reanalysis data suggest that summertime high pressure systems in the Northern Hemisphere subtropics will intensify as a result of climate change.