August 3, 2007, 9:52 PM CT

Explorers' Limited Ability To Navigate

When explorers like Magellan and Columbus sailed from Europe to the New World 500 years ago, they amazingly managed to navigate the open sea without terrestrial landmarks, natural boundaries or the navigational technology we have today.

Historical reports show that some explorers and other seafaring people did so by imagining an island just over the horizon; if they kept track of where the "virtual island" was, they knew which direction to go in the open water.

But new research from the University of Iowa suggests that people's ability to imagine virtual islands -- without any perceptual cues to help -- is quite limited. Consistent with this, studies of how seafaring people navigate on the open seas suggest they actually rely on two key perceptual cues: perception of their own motion and the boat's motion. Thus, the ability to navigate in open water stems from how the body senses motion, not on a mental ability to imagine a point.

In a paper published this month in the Journal of Experimental Psychology: Human Perception and Performance, doctoral candidate Vanessa Simmering and associate professor John Spencer, both of the Department of Psychology in the UI College of Liberal Arts and Sciences, provide evidence that adults cannot arbitrarily carve the world into spatial regions. Instead, they write, people must rely on perceptual cues for help. The paper is titled "Carving Up Space at Imaginary Joints: Can People Mentally Impose Arbitrary Spatial Category Boundaries?"......... Posted by: Tyler      Read more         Source

Fri, 03 Aug 2007 05:22:04 GMT

UN Asks Developed Nations to Further Cut Emissions

A UN special meet on climate change harped on the developed world to carry more of the burden of tackling greenhouse emissions. Warning that if let loose to envelope the planet, these carbon emissions will choke the atmosphere poisoning the man-friendly environment, the UN also called for less-developed nations to contribute their bit in cooling the atmosphere.

Every one of us is familiar of the havoc that carbon emissions are wreaking in the atmosphere, raising mercury levels to an extent that calls for urgent attention. Relentless development, reckless industrialization, merciless destruction of flora is fuelling the atmosphere to an extent that would devour the entire planet one day. Human warming of the planet in the form of carbon emissions propelled by petrol eating vehicles, power plants, and industries is discharging innumerable pollutants into the atmosphere resulting in a rise in global temperatures.

The earth has already started showing dangerous signs of times to come. Melting glaciers, flooding, droughts, constant hurricanes, rising seas, dying creatures, and what not, all is the result of global climate change.

British economist Nicholas Stern acknowledges that carbon dioxide emissions need to be curtailed by at least 50 percent by 2050, if we want the earth to remain a green planet forever. Necessitating the need for cuts Stern asserts,

Because of reasons of past responsibility and better access to resources, the rich countries should take much bigger objectives than that 50 percent. They should be looking for around 75 percent cuts.

The better-placed richer nations must share most of the responsibility to financing cuts in emissions in poor undeveloped countries, which are fighting poverty and have no resources to their avail to contain emissions. Industrialized developed nations need to review their policy on climate change by allowing opportunities like carbon trading and offsetting to prosper.

Sunita Narain, director of India’s Center for Science and Environment, in her address snubbed the richer developed nations for the disproportionate sharing of the emissions. Asserting that the need of the day is an urgent attention on behalf of the developed world to share the ecological imbalance considerably, Narain retorts,

The rich world has to reduce emissions far more drastically than it has done so to date. The political leadership is very high on rhetoric but very low on real action when it comes to delivering the goods on climate change.

At a time, when most of the nations of the world are fighting a bizzare change in climate in the form of floods in one part and droughts in the other, risking everyone from humans to animals, a global consensus on reining global warming has to be reached.

The developed countries should start searching environment technology to support the environment rather than snubbing poor underdeveloped nations to cut their development for the sake of global climate. Is the developed world right in asking for such a huge demand from the poor nations, whose economy still needs wheels to sustain itself and run? If restraining their development process will hurt their economy, then how can rich countries ask for cuts from the poor nations? It is the bounden duty of the rich developed nations to lead from the front in a global effort to tackle global warming.

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August 1, 2007, 9:00 PM CT

Pollution Amplifies Greenhouse Gas Warming Trends

Researchers have concluded that the global warming trend caused by the buildup of greenhouse gases is a major contributor to the melting of Himalayan and other tropical glaciers. Now a new analysis of pollution-filled "brown clouds" over south Asia by scientists at Scripps Institution of Oceanography at UC San Diego offers hope that the region may be able to arrest some of the alarming retreat of such glaciers by reducing its air pollution.

The team led by Scripps atmospheric chemistry professor V. Ramanathan describes findings that atmospheric brown clouds enhanced solar heating of the lower atmosphere by about 50 percent in a paper to be released in the Aug. 2 edition of the journal Nature. The combined heating effect of greenhouse gases and the brown clouds, which contain soot, trace metals and other particles from a growing cadre of urban, industrial and agricultural sources, is enough to account for the retreat of Himalayan glaciers observed in the past half century, the scientists concluded. The glaciers supply water to major Asian rivers including the Yangtze, Ganges and Indus. These rivers in turn comprise the chief water supply for billions of people in China, India and other south Asian countries.

"The rapid melting of these glaciers, the third-largest ice mass on the planet, if it becomes widespread and continues for several more decades, will have unprecedented downstream effects on southern and eastern Asia," the Nature article concluded......... Posted by: Tyler      Read more         Source

Wed, 25 Jul 2007 04:00:53 GMT

Are We Heading Towards a Vegetarian Diet?

There have been always arguments whether vegetarian or non veg diet is good for human health. Logics come flooding supporting each options almost equally. But a recent study shows somehow vegetarians are doing a favour almost unknowingly towards the reduction of greenhouse effects. Beware meat eaters; may be you are directly contributing towards global warming. In a recent study it is claimed that producing 2.2lb of beef generates as much greenhouse gas as of a car that runs nonstop for three hours. Most of the greenhouse gas emissions are in form of methane, released from the digestive system of the animal. Su Taylor, the press officer for the Vegetarian Society, told New Scientist

Everybody is trying to come up with different ways to reduce carbon footprints, but one of the easiest things you can do is to stop eating meat

There has been strange and unusual ways that cause global warming. Now with a burning issue of green house effect and the environmental change in all over the world, this research will be a shock to those who live on a non veg diet. If the theory is proved, then there will be a speculation whether beef or other meat products should be banned worldwide.

This is however, a complex situation. People are always reluctant to change a single thing from their lifestyle in order to prevent global warming. There has been some awareness these days, but in spite of that the effect of global warming is gradually increasing everyday. So there will be a strong protest from the people who specially depend on meat products for their living. This study may spark controversies all over, as there will be no way to actually prevent people from eating meat. This will be completely unbelievable to introduce legislation to prevent the entire human community stop eating meat and rely on vegetarian diet. But if further research confirms this story, then we will definitely need some measure to control the use of meat. May be the time has come to rely on some alternative diet.

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July 19, 2007, 10:16 PM CT

Unique Volcanic Mudflow in Action in New Zealand

Volcanologist Sarah Fagents from the School of Ocean and Earth Science and Technology (SOEST) at the University of Hawaii at Manoa had an amazing opportunity to study volcanic hazards first hand, when a volcanic mudflow broke through the banks of a volcanic lake at Mount Ruapehu in New Zealand.

Fagents and his colleagues were there on a National Science Foundation (NSF)-funded project to study the long-forecast Crater Lake break-out lahar at Mount Ruapehu. A lahar is a type of mudflow composed of water and other sediment that flows down from a volcano, typically along a river valley.

Lahars are caused by the rapid melting of snow and/or glaciers during a volcanic eruption, or as in the case of Mount Ruapehu, the breakout of a volcanic lake.

"Lahars can be extremely hazardous, particularly in populated areas, because of their great speed and mass," said William Leeman, NSF program director for petrology and geochemistry. "They can flow for a number of tens of miles, causing catastrophic destruction along their path. The 1980 eruptions at Mount St. Helens, for example, resulted in spectacular lahar flows that choked virtually all drainages on the volcano, and impacted major rivers as far away as Portland, Ore".

Fagents visited stretches of the lahar pathway before the breakout to assess pre-event channel conditions. Eventhough the event was predicted to occur in 2007, the recent decreased filling rate of Crater Lake suggested that the lake bank actually would not be overtopped until 2008......... Posted by: Tyler      Read more         Source

July 19, 2007, 10:11 PM CT

Glaciers and Ice Caps to Dominate Sea Level Rise

Ice loss from glaciers and ice caps is expected to cause more global sea rise during this century than the massive Greenland and Antarctic ice sheets, as per a new University of Colorado at Boulder study.

The researcher, primarily funded by the National Science Foundation (NSF) and NASA, concluded that glaciers and ice caps are currently contributing about 60 percent of the world's ice to the oceans and the rate has been markedly accelerating in the past decade, said Emeritus Professor Mark Meier of CU-Boulder's Institute of Arctic and Alpine Research, lead study author. The contribution is presently about 100 cubic miles of ice annually -- a volume nearly equal to the water in Lake Erie -- and is rising by about three cubic miles per year.

In contrast, the CU-Boulder team estimated Greenland is now contributing about 28 percent of the total global sea rise from ice loss and Antarctica is contributing about 12 percent. Greenland is not expected to catch up to glaciers and ice caps in terms of sea level rise contributions until the end of the century, as per the study.

A paper on the subject appears in the July 19 issue of Science Express, the online edition of Science magazine. Co-authors include CU-Boulder INSTAAR scientists Mark Dyurgerov, Ursula Rick, Shad O'Neel, Tad Pfeffer, Robert Anderson and Suzanne Anderson, as well as Russian Academy of Sciences scientist Andrey Glazovsky......... Posted by: Tyler      Read more         Source

Thu, 19 Jul 2007 01:06:34 GMT

Brazil to Build Dams Despite Environmental Concerns

Despite high chances to kick up yet another bilateral dispute between Bolivia and Brazil, the $11.6 billion controversial hydroelectric plants are to get a green signal for construction.

Bolivia, Foreign Minister Celso Amorim seems to be more concerned about the rights of possession than his countrys citizens right to survive in a healthy environment.

Yes, building the two large dams in the Amazon region will lead to various environmental problems, as it always does when is interfered with.

According to the environmentalists, though the two dams with a total capacity of 6,500 megawatts will increase Brazil’s power generation leading to economic growth in the next decade, they would not only disrupt the regions biodiversity, but the silt that would possibly accumulate along the rivers will impact both the river and its lives.

In reference to the proposed dams, Amorim told Valor newspaper,

We are not going to stop doing things that are our right.

Bolivia claims that the authorities had issued the go ahead without studying the environmental and social impacts on the on the Madeira River on which the new dams will be built. Concerned about the project, it requested Brazil for a high-level meeting.

But, the chance for the political big guns to compromise with the business gain from the project for the cause of the environment seems grim after all, money matters.

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July 12, 2007, 10:58 PM CT

Breath Of Volcano

Indonesia's Mount Gamkonora volcano is spewing hot ash and smoke into the air, as seen in this image taken by the MERIS instrument aboard ESA's satellite Envisat, causing more than 8000 people to be evacuated amid fears of an imminent eruption, as per officials.

Officials raised the alert to the highest level on Tuesday after the volcano, located in the eastern province of North Maluku, started spitting out flaming material, indicating magma was approaching the crater's surface making an eruption more likely, Saut Simatupang of Indonesia's Vulcanological Survey told Reuters news agency.

The 1635m volcano, located about 2400 km northeast of Jakarta, began releasing smoke and ash on Saturday and spewed it as high as 4000m on Monday. Mount Gamkonora is the highest peak on Halmahera Island.

Indonesia is located within the Pacific 'Ring of Fire', a continuous line (40 000 km long) of volcanoes and fault lines circling the edges of the Pacific Ocean, and has more than a hundred active volcanoes within its territory.

The majority of the 1500 active volcanoes on the Earth's surface, of which around 50 erupt each year, are located along the Pacific 'Ring of Fire'. At least 500 million people live close to an active volcano.

As world population increases, so does the potential threat from every eruption. Eventhough there is no way ground-based monitoring can be carried out on all volcanoes across the globe, space-based monitoring helps identify the volcanoes presenting the greatest danger......... Posted by: Tyler      Read more         Source

July 12, 2007, 8:05 PM CT

Fragmented Structure of Seafloor

A number of earthquakes in the deep ocean are much smaller in magnitude than expected. Geophysicists from the Woods Hole Oceanographic Institution (WHOI) have found new evidence that the fragmented structure of seafloor faults, along with previously unrecognized volcanic activity, may be dampening the effects of these quakes.

Examining data from 19 locations in the Atlantic, Pacific, and Indian oceans, scientists led by graduate student Patricia Gregg have observed that "transform" faults are not developing or behaving as theories of plate tectonics say they should. Rather than stretching as long, continuous fault lines across the seafloor, the faults are often segmented and show signs of recent or ongoing volcanism. Both phenomena appear to prevent earthquakes from spreading across the seafloor, thus reducing their magnitude and impact.

Gregg, a doctoral candidate in the MIT/WHOI Joint Program in Oceanography and Oceanographic Engineering, conducted the study with seismologist Jian Lin and geophysicists Mark Behn and Laurent Montesi, all from the WHOI Department of Geology and Geophysics. Their findings were reported in the July 12 issue of the journal Nature.

Oceanic transform faults cut across the mid-ocean ridge system, the 40,000-mile-long mountainous seam in Earth's crust that marks the edges of the planet's tectonic plates. Along some plate boundaries, such as the Mid-Atlantic Ridge, new crust is formed. In other regions, such as the western Pacific, old crust is driven back down into the Earth......... Posted by: Tyler      Read more         Source

Fri, 06 Jul 2007 04:23:35 GMT

Chilean Lake Disappears, Thanks to Climate Change

Climate change or change in climate, call it this or that way it spells only havoc. We need no illustrations to recall the impact global rise in temperatures is having on us and on our mother earth. With mercury surging fast, glaciers melting swiftly, oceans inundating coasts, lakes disappearing, marine creatures showing extinction, times ahead can only be imagined. What are we all up to? How long civilization endures can be no ones guess. With global warming spreading its tentacles, who is to be blamed?

First it was Lake Superior, the largest freshwater lake on earth showing signs of drying up, and now a glacial lake in southern Chile has disappeared, leaving a 40-meter deep crater behind, thanks to global warming. And to no ones doubt the scientists too charged climate change as the culprit. They state that as rising temperatures led to the melting of the nearby glaciers, the process raised the water pressure around, leading to the water running into the sea, resulting in the disappearance of the lake.

Chile is not the only case. Similar phenomenon has also been recorded earlier in various parts of the world. Also the news of glacier retreat in Greenland and Antarctica has already sent shivering waves around.

Do we need more examples to convince ourselves of the havoc being reaped by global warming? It is being surmised by the scientific community all around that if temperatures keep rising the way they are, the time is not far when the dragon of global warming would bring life to a standstill on earth.

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