April 10, 2008, 9:27 PM CT

How strong is a hurricane?

Knowing how powerful a hurricane is, before it hits land, can help to save lives or to avoid the enormous costs of an unnecessary evacuation. Some MIT scientists think there may be a better, cheaper way of getting that crucial information.

So far, there's only one surefire way of measuring the strength of a hurricane: Sending airplanes to fly right through the most intense winds and into the eye of the storm, carrying out wind-speed measurements as they go.

That's an expensive approach--the specialized planes used for hurricane monitoring cost about $100 million each, and a single flight costs about $50,000. Monitoring one approaching hurricane can easily require a dozen such flights, and so only storms that are approaching U.S. shores get such monitoring, even though the strongest storms occur in the Pacific basin (where they are known as tropical cyclones).

Nicholas Makris, associate professor of mechanical and ocean engineering and director of MIT's Laboratory for Undersea Remote Sensing, thinks there may be a better way. By placing hydrophones (underwater microphones) deep below the surface in the path of an oncoming hurricane, it's possible to measure wind power as a function of the intensity of the sound. The roiling action of the wind, churning up waves and turning the water into a bubble-filled froth, causes a rushing sound whose volume is a direct indicator of the storm's destructive power......... Posted by: Tyler      Read more         Source

April 10, 2008, 9:19 PM CT

Hurricane Forecasters Adopt NCAR Radar Technique

The National Hurricane Center will implement a new technique this summer, developed by scientists at the National Center for Atmospheric Research (NCAR) and the Naval Research Laboratory (NRL), to continually monitor landfalling storms in the United States. The system, which relies on existing coastal Doppler radars, provides details on hurricane winds and central pressure every six minutes, indicating whether a hurricane is gathering strength in its final hours before reaching shore.

The technique, known as VORTRAC (Vortex Objective Radar Tracking and Circulation), was successfully tested by the National Hurricane Center last year.

"VORTRAC will enable hurricane specialists, for the first time, to continually monitor the trend in central pressure as a dangerous storm nears land," says NCAR scientist Wen-Chau Lee. "With the help of VORTRAC, vulnerable communities can be better informed of sudden changes in hurricane intensity".

Lee collaborated with NRL's Paul Harasti and NCAR's Michael Bell to develop VORTRAC. Funding came primarily from the National Science Foundation and the National Oceanic and Atmospheric Administration. The NHC is part of NOAA's National Weather Service.

One of VORTRAC's strengths is that it can use radar data to estimate the barometric pressure at the center of a hurricane, a key measure of its intensity......... Posted by: Tyler      Read more         Source

April 10, 2008, 9:05 PM CT

Grand Canyon may be as old as dinosaurs

New geological evidence indicates the Grand Canyon may be so old that dinosaurs once lumbered along its rim, as per a research studyby scientists from the University of Colorado at Boulder and the California Institute of Technology.

The team used a technique known as radiometric dating to show the Grand Canyon may have formed more than 55 million years ago, pushing back its assumed origins by 40 million to 50 million years. The scientists gathered evidence from rocks in the canyon and on surrounding plateaus that were deposited near sea level several hundred million years ago before the region uplifted and eroded to form the canyon.

A paper on the subject would be reported in the recent issue of the Geological Society of America Bulletin. CU-Boulder geological sciences Assistant Professor Rebecca Flowers, lead author and a former Caltech postdoctoral researcher, collaborated with Caltech geology Professor Brian Wernicke and Caltech geochemistry Professor Kenneth Farley on the study.

"As rocks moved to the surface in the Grand Canyon region, they cooled off," said Flowers. "The cooling history of the rocks allowed us to reconstruct the ancient topography, telling us the Grand Canyon has an older prehistory than a number of had thought".

The team believes an ancestral Grand Canyon developed in its eastern section about 55 million years ago, later linking with other segments that had evolved separately. "It's a complicated picture because different segments of the canyon appear to have evolved at different times and subsequently were integrated," Flowers said......... Posted by: William      Read more         Source

April 8, 2008, 9:49 PM CT

Sea salt worsens coastal air pollution

Air pollution in the worlds busiest ports and shipping regions may be markedly worse than previously suspected, as per a new study showing that industrial and shipping pollution is exacerbated when it combines with sunshine and salty sea air.

In a paper published in this weeks advance online edition of the journal Nature Geoscience, a team of scientists that included University of Calgary chemistry professor Hans Osthoff report that the disturbing phenomenon substantially raises the levels of ground-level ozone and other pollutants in coastal areas.

We found unexpectedly high levels of certain air pollutants where pollution from cities and ships meets salt in the ocean air along the southeast coast of the United States, said Osthoff, who joined the U of Cs Department of Chemistry last August. It only makes sense that this is a problem everywhere industrial pollution meets the ocean, as is the case in a number of of the largest cities around the world. It also changes our view of the chemical transformations that occur in ship engine exhaust plumes, and tells us that emissions from marine vessels may be polluting the globe to a greater extent than currently estimated.

Dr. Osthoff was part of a National Oceanic and Atmospheric Administration (NOAA) team that spent six weeks monitoring air quality in busy shipping areas off the southeastern coast of the United States between Charleston, South Carolina and Houston, Texas, in the summer of 2006. The scientists found unexpectedly high levels of nitryl chloride (ClNO2), a chemical long suspected to be involved in ground-level ozone production along the coast. They then determined that the compound is efficiently produced at night by the reaction of the nitrogen oxide N2O5 in polluted air with chloride from sea salt. With the help of sunlight, the chemical then splits into radicals that accelerate production of ozone and, potentially, fine particulate matter, which are the main components of air pollution. Their findings also show that up to 30 per cent of the ground-level ozone present in seaside cities such as Houston may be the result of pollution mixing with salt from ocean mist......... Posted by: Tyler      Read more         Source

April 7, 2008, 10:39 PM CT

NOAA Aircraft to Probe Arctic Pollution

NOAA researchers are now flying through springtime Arctic pollution to find out why the region is warming - and summertime sea ice is melting - faster than predicted. Some 35 NOAA scientists are gathering with government and university colleagues in Fairbanks, Alaska, to conduct the study through April 23.

"The Arctic is changing before our eyes," said A.R. Ravishankara, director of the chemistry division at NOAA's Earth System Research Laboratory in Boulder, Colo. "Capturing in detail the processes behind this large and surprisingly rapid transformation is a unique opportunity for understanding climate changes occurring elsewhere."

Observations from instruments on the ground, balloons, and satellites show the Arctic is warming faster than the rest of the globe. Summer sea-ice extent has decreased by nearly 40 percent in comparison to the 1979-2000 average, and the ice is thinning.

Industry, transportation, and biomass burning in North America, Europe, and Asia are emitting trace gases and tiny airborne particles that are polluting the polar region, forming an "Arctic Haze" every winter and spring. Researchers suspect these pollutants are speeding up the polar melt.

Called ARCPAC (Aerosol, Radiation, and Cloud Processes affecting Arctic Climate Change), the project is a NOAA contribution to International Polar Year 2008. The experiment will be coordinated with the agency's long-term climate monitoring station at Barrow, Alaska, and with simultaneous projects conducted by NASA and the Department of Energy......... Posted by: Tyler      Read more         Source

April 7, 2008, 9:16 PM CT

'Revolutionary' CO2 maps zoom in on greenhouse gas sources

Where CO2 is being emitted interactive map of U.S. carbon dioxide emissions from fossil fuels has observed that the emissions aren't all where we thought.

"For example, we've been attributing too a number of emissions to the northeastern United States, and it's looking like the southeastern U.S. is a much larger source than we had estimated previously," says Kevin Gurney, an assistant professor of earth and atmospheric science at Purdue University and leader of the project.

The maps and system, called Vulcan, show CO2 emissions at more than 100 times more detail than was available before. Until now, data on carbon dioxide emissions were reported, in the best cases, monthly at the level of an entire state. The Vulcan model examines CO2 emissions at local levels on an hourly basis.

Scientists say the maps also are more accurate than prior data because they are based on greenhouse gas emissions instead of estimates based on population in areas of the United States.

To create the Vulcan maps, the research team developed a method to extract the CO2 information by transforming data on local air pollution, such as carbon monoxide and nitrous oxide emissions, which are tracked by the Environmental Protection Agency, the U.S. Department of Energy and other governmental agencies......... Posted by: Tyler      Read more         Source

April 3, 2008, 8:44 PM CT

The voyage to America

Professor Eske Willerslev was surprised by the results of the DNA tests conducted by himself and colleagues on samples of what turned out to be fossilised human faeces found in deep caves in the Oregon desert. The oldest of the droppings have been carbon-dated to be approximately 14,340 years old. Willerslevs faeces samples clearly contain two main genetic types of Asian origin that are unique to present-day North American Indians. Not only is this proof that the American Indians are descendants of the first immigrants to the continent, it is also proof that immigration took place approximately 1,000 years earlier than otherwise believed.

The American continent was the last of the worlds continents to be populated. There are a number of contradictory and more or less well-founded scientific theories on when this occurred and from where the first immigrants came. These theories span from immigration via the icy Atlantic Ocean to Thor Heyerdahls papyrus boat expeditions from Africa to America. The most accepted theory is based on findings of stone tools from the Clovis culture in soil layers dating back to approximately 13,000 BC. As per the theory, people from Siberia migrated, perhaps in search of mammoth, across the land bridge that once connected Siberia and North America. From there, they continued south and spread out across the American continent. The migration passed through a corridor that opened up approximately 14,000 years ago in the giant glacier that covered the American continent. But these new findings call this immigration theory into question......... Posted by: Tyler      Read more         Source

April 1, 2008, 9:04 PM CT

Geologist decries floodplain development

Midwesterners have to be wondering: Will April be the cruelest month?.

Patterns in the Midwest this spring are eerily reminiscent of 1993 and 1994, back-to-back years of serious flooding. The great flood of 1993 caused nearly $20 billion of economic damage, damaging or destroying more than 50,000 homes and killing at least 38 people.

Parallels this year include abnormally high levels of precipitation in late winter and early spring, and early flooding in various regions. In March, Missouri, Arkansas and Illinois and the Ohio River experienced flooding. A still-unknown factor is the effect of the snow melt from upstream states on river systems this spring and summer. Wisconsin, for example, had record amounts of snow this winter.

Despite the similarity in conditions and periods of flooding nearly every year after those flood years more than a decade ago, one thing Midwesterners have not learned is "geologic reality," says Robert E. Criss, Ph.D., professor of earth and planetary sciences in Arts & Sciences at Washington University in St. Louis.

"When people build commercial or residential real estate in flood plains, when they build on sink holes, when they build on fault lines, when they build on the hillsides in L.A. that are going to burn and burn, over and over again, they're ignoring geologic reality," Criss says. "They're asking for chronic problems."........ Posted by: Tyler      Read more         Source

Mon, 31 Mar 2008 00:39:56 GMT

Carbon principles

Earlier this month, I did a blog entry looking at the massive impact that climate change will have on the financial services sector, particularly the banks.

Now, global law firm Winston & Strawn has put out a briefing paper on the carbon principles being championed by Citibank, JPMorgan Chase, and Morgan Stanley working in conjunction with various power companies. According to the principles, the aim is to encourage companies to invest in renewable energy and carbon technology. The principles are however a bit vague when it comes to dealing with certain industries, like power plants. Significantly, it seems to make no distinction between natural gas, coal or nuclear plants.

The principles don't preclude financing of projects producing greenhouse gas emissions. But they are likely to force these industries to look more carefully at what they do and find ways to address the issue.

And bank clients who won't provide the information required to conduct what the principles call the enhanced diligence process will be denied financing. Posted by: leon      Read more     Source

March 27, 2008, 9:14 PM CT

Dramatic developments at Kilauea Volcano

Explosive eruptions and noxious gas emissions at Kilauea Volcano in Hawaii this week have prompted researchers to work around the clock to understand what will happen next and how to keep the public out of harms way.

Researchers are monitoring gas emissions and seismic activity at Kilauea, which on March 19 experienced its first explosive eruption since 1924. The volcano is also emitting sulfur dioxide at toxic levels.

The National Park Service has closed Crater Rim Drive through the south caldera area until further notice. The U.S. Geological Survey is issuing frequent updates, which can be accessed at http://hvo.wr.usgs.gov/kilauea/.

Sulfur dioxide emissions at the volcanos summit have increased to a rate that is likely to be hazardous for areas downwind of Halema'uma'u crater. Future explosions from Halema'uma'u Crater are possible.

This historic activity has created new hazards that did not exist before explosive eruptions as well as toxic sulfur dioxide emissions in the middle of a national park, said U.S. Geological Survey Volcano Hazards Program Coordinator John Eichelberger. Our job is to give emergency responders and the civil defense community the very best information we can provide about what the volcano is doing and what it is likely to do in the future......... Posted by: Tyler      Read more         Source