Volume 3 Issue 11, November 2010

The 2010 Haiti earthquake showed that building codes must be adopted and strictly enforced. Furthermore, timely disaster recovery requires these codes to be supplemented by comprehensive hazard-insurance programmes.

Geoscience has played a key role in the recovery of Haiti since the earthquake, but warnings were not heeded in the political sphere. Along with better houses, an adaptive disaster-management infrastructure that incorporates science needs to be built.

The Haiti earthquake ruptured one or more buried faults, generated tsunamis and caused extensive structural damage in Port-au-Prince. Investigations in the epicentral region quantify seismic hazards but offer no clear views of Haiti's seismic future.

Evidence for the sedimentary carbonate rocks proposed to be prevalent on Mars has generally been lacking. Carbonate-bearing rocks found in the Leighton Crater may be associated with the formation of methane detected in the martian atmosphere.

On average, terrestrial near-surface winds have slowed down in recent decades. This change will affect both wind energy and hydrology.

Wetlands are home to microorganisms that produce and emit methane. Very small wetlands, tucked into unexpected places, might be making a larger contribution to the global methane budget than previously thought.

Mars may have once had a CO₂-rich atmosphere, but carbonate rocks that could provide evidence for such conditions are sparse. Spectral analyses of rocks exposed from deep within an impact crater reveal that carbonate deposits may be extensive on Mars, but are buried under layers of younger volcanic rocks.

Surface winds have declined in China, the Netherlands, the Czech Republic, the United States and Australia over the past few decades. Mesoscale model simulations suggest that an increase in surface roughness is contributing to the stilling trend in the mid-latitude Northern Hemisphere.

Decadal fluctuations in the North Pacific Ocean and overlying atmosphere significantly affect the weather and climate of North America and Eurasia. An ensemble of simulations with a coupled ocean–atmosphere model reveals a link between these decadal oscillations and central Pacific El Niño events.

Methane concentrations above tropical forests in the neotropics are high, according to space-borne observations. Flux measurements in the field suggest that tank bromeliads, herbaceous plants common throughout tropical forests, emit methane and may contribute to the tropical source.

Radiocarbon-depleted carbon dioxide was released to the atmosphere at the end of the last glacial period, but its source remains controversial. Neodymium isotope records of deglacial intermediate water circulation in the eastern North Pacific Ocean from fish teeth support a Southern Ocean source.

Ocean islands formed over hotspots can uplift and subside as the hotspots evolve. The history of the Cape Verde islands reveals large-scale uplift owing to growth of the hotspot swell, but also variable uplift of individual islands resulting from the local intrusion of magma.

Microzonation maps use local geological conditions to characterize seismic hazard, but do not generally consider topography. Ground motions during the Haiti earthquake are found to have been significantly amplified along a high topographic ridge, which caused substantial structural damage, indicating that topography can play an important role in seismic hazard.

The 12 January 2010 M_w 7.0 Haiti earthquake exhibited primarily strike-slip motion but unusually generated a tsunami. An extensive field survey reveals that coastal strike-slip fault systems produce relief conducive to rapid sedimentation, erosion and slope failure, so that even modest predominantly strike-slip earthquakes can cause potentially catastrophic slide-generated tsunamis.

The Enriquillo–Plantain Garden fault zone is the primary plate-bounding fault system in Haiti and was initially thought to be responsible for the 2010 earthquake. Palaeoseismic analyses of the fault system indicate that it ruptured during a large earthquake in either 1750 or 1770, but did not rupture during the 2010 earthquake.

The Enriquillo–Plantain Garden strike-slip fault accommodates the relative motion between the North American and Caribbean plates and was thought to have ruptured during the 2010 Haiti earthquake. Satellite data instead indicate that a blind thrust fault, possibly related to the Haitian fold–thrust belt, was responsible and caused some contractional deformation.

Initially, the devastating 12 January 2010 Haiti earthquake seemed to involve straightforward accommodation of the motion between the Caribbean and North American plates. A combination of seismological observations, geologic field data and space geodetic measurements shows that the rupture process may have involved slip on multiple faults, but lacked significant surface deformation.

Matthew J. Hornbach and colleagues navigated shallow debris-filled waters in an attempt to understand the factors that contributed to tsunami generation during the Haiti earthquake.

Susan E. Hough and colleagues faced logistical challenges when attempting to deploy portable seismometers in post-earthquake Port-au-Prince.

The January 2010 Haiti earthquake was catastrophic, leaving one million homeless. In this focus issue we have gathered articles — ranging from primary research to opinion pieces — that explore the physical processes responsible for the earthquake and the damage caused, as well as the humanitarian problems now facing the poorest country in the western hemisphere.