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13 November 2014

Satellite nightlight images show flood exposure increasing worldwide

More people around the world live in flood-prone regions than did 20 years ago, increasing death tolls and economic damage from floods and the chances that flooding will cause similar losses in the future, a new study finds. The increased concentration of human populations in flood-risk zones could exacerbate an already expected upsurge in flood-related destruction in a warming climate, the researchers report.
The study has been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union. Its authors used satellite images to show that a widely used proxy for population—the number of lights seen at night—increased globally along rivers by an average of 1.2 percent each year between 1992 and 2012.

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5 August 2014

Sea-level spikes can harm beaches worse than hurricane

Unforeseen, short-term increases in sea level caused by strong winds, pressure changes and fluctuating ocean currents can cause more damage to beaches on the East Coast over the course of a year than a powerful hurricane making landfall, according to a new study. The new research suggests that these sea-level anomalies could be more of a threat to coastal homes and businesses than previously thought, and could become higher and more frequent as a result of climate change.

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22 July 2014

Oso disaster had its roots in earlier landslides

The disastrous March 22 landslide that killed 43 people in the rural Washington state community of Oso involved the “remobilization” of a 2006 landslide on the same hillside, a new federally sponsored geological study concludes.

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14 August 2013

Around the world in four days: NASA tracks Chelyabinsk meteor plume

Atmospheric physicist Nick Gorkavyi missed witnessing an event of the century last winter when a meteor exploded over his hometown of Chelyabinsk, Russia. From Greenbelt, Md., however, NASA’s Gorkavyi and colleagues witnessed a never-before-seen view of the atmospheric aftermath of the explosion.

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4 June 2013

Return to Tohoku – Taking a big quake’s temperature

There’s a hole in the bottom of the ocean near Japan, the deepest ever drilled for science. It leads to the heart of one of the world’s most dangerous faults, the one that unleashed the 2011 Tohoku earthquake and tsunami, which devastated Japan’s east coast. The earthquake’s power astonished geologists, who didn’t think the fault was capable of such destruction.To find out why the quake was so massive, an international team drilled through more than 800 meters of rock, seven kilometers beneath the waves, to take the fault’s temperature.

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3 June 2013

Hurricane Sandy took highly unusual path, but climate change doesn’t get the blame – yet

Hurricane Sandy’s peculiar path was exceedingly rare, but whether or not climate change influenced the trajectory remains unknown, new research suggests. Sandy differed from most North Atlantic hurricanes by veering west over the northeastern United States and merging with a winter storm. But nothing proved more unusual about the “superstorm” than the nearly perpendicular angle at which it approached the New Jersey shoreline and collided with the coast on October 29, 2012. Usually, hurricanes graze the coast rather than plunging into it head on.

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19 April 2013

Exploring a changing coast in the face of sea level rise – Galveston, Texas

Over 80 scientists gathered at a conference here this week to share their latest research on past, current, and projected future sea level rise and to discuss how this information can be used to shape policy. Despite their diverse perspectives and expertise, one thing the scientists agreed on for sure: the rates and impacts of sea level rise are local and communities are facing a growing risk.

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13 December 2012

Secret tsunamis of the South Pacific

The crumbling volcanic islands of the southern Pacific Ocean could be a major source of undocumented – and potentially dangerous – tsunamis.

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6 December 2012

Ground under ancient Chilean volcano is rising fast

The Laguna del Maule volcanic field in the Chilean Andes Mountains lies in the heart of volcano country. The region is a well-known subduction zone, where the friction of one crustal plate sliding under another heats rock to form magma. But for the last 2,000 years, Laguna del Maule has been a quiet water-filled caldera. Now, scientists are recording rapid deformation of the land around the caldera, suggesting that a magma reservoir is inflating below the surface.

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5 December 2012

Glacial quakes mask those warning of volcanic eruptions

Swarms of tiny, repeating earthquakes often precede volcanic unrest, as they did prior to the 1989 eruption of Alaska’s Mount Redoubt. New research at Mount Rainier in Washington state finds that glaciers produce similar low magnitude seismic shocks that are not predictive of volcanic activity, and that could be interfering with efforts to predict when a dangerous eruption is imminent.

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Tsunamis in the sky

High in the sky seems like an unusual place to look for a tsunami, a natural disaster created deep beneath the ocean’s surface. But an international team of researchers is scanning the atmosphere for signs of these hazards. Looking at the sky, they say, could help scientists and emergency response agencies improve warning systems before they see any problems on land.

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23 August 2012

The rare 5.8 Virginia earthquake: One year later

One year ago today, the Washington Monument – along with many other buildings in Washington, D.C. – shook as a 5.8 magnitude earthquake centered near Mineral, Va., rattled the ground beneath it. Since then, experts have deemed the structure unsafe for tourists to enter and estimated that the monument suffered tens of millions of dollars in damage that will take years to repair. Despite these setbacks, the rare seismic event sparked a new era in earthquake assessment in the eastern U.S.

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10 August 2012

Mini maars

A while back, I wrote about UB’s exciting new facility for experimental volcanology, which is part of our Center For Geohazards Studies. The facility itself isn’t anything like a big fancy laboratory – it’s out in the country and is mainly open space. But that’s a perfect setting for making holes in the ground, which (in a very basic sort of way) was the whole point of the most recent test. Volcanologists and engineers from UB, Italy, and New Zealand were all present for this explosive event:

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21 June 2012

AGU interviews astronauts in space

AGU Video: On 19 June, AGU had the unique opportunity to interview three astronauts aboard the International Space Station about what it’s like to live in orbit and study the Earth from space. Astronauts Joe Acaba (NASA), André Kuipers (ESA) and Don Pettit (NASA) answered questions about their everyday lives in orbit, the hazards of life in space and how their experiences in microgravity have affected their thoughts about our home planet. Watch the video interview here!

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15 June 2012

Volcanic impacts on everyday life — circa 1600

Massive volcanic eruptions that spew sulfur-rich particles into the atmosphere can disrupt climate around the globe, leading to cooler temperatures worldwide. Researchers can track the impacts by looking at ice cores or tree rings that record summer growth, but a different approach involves scouring through historical records to see what kind of an impact these volcanic explosions had on everyday life.

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11 June 2012

Potential Iceland eruption could pump acid into European airspace

A modern recurrence of an extraordinary type of volcanic eruption in Iceland could inject large quantities of hazardous gases into North Atlantic and European flight corridors, potentially for months at a time, a new study suggests. Using computer simulations, researchers are investigating the likely atmospheric effects if a “flood lava” eruption took place in Iceland today.

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21 May 2012

Monitoring earthquakes with GPS could yield faster disaster response

When the March 2011 earthquake shook Japan, scientists needed about 20 minutes to conduct a full analysis. But now, researchers have found a way to shrink that critical analysis time for large earthquakes to two minutes. The speedup results from using data from GPS networks for the initial evaluation, rather than readings of seismometers.

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1 May 2012

Using science to disarm disaster

When it comes to natural hazards, early warnings and preparedness are key, federal and local government officials stressed at the American Geophysical Union’s inaugural Science Policy Conference in Washington, DC, Tuesday.

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8 December 2011

Japanese megaquake triggered tiny California tremors

As southern Californians absorbed the news of the devastating March 11 earthquake in Japan, seismic instruments under their feet sensed the shocks as well.

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14 September 2011

Atmospheric electrons may act differently before megaquakes

Just before the recent huge earthquake in Japan, electron counts in the atmosphere high above the epicenter took a surprising turn, a new study indicates. Measurements gleaned from GPS satellites recorded more electrons in the ionosphere over the soon-to rupture fault than expected. A similar uptick occurred before extra-large quakes in Chile in 2010 and Sumatra in 2004, the researcher found.

A tantalizing question for seismologists and atmospheric scientists is whether this high-altitude electron bump, if confirmed by other studies, is a true early-warning signal for devastating earthquakes.

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