Archive for the ‘Ocean’ Category

Deep water discovered towards Earth’s core

“This water is much deeper than ever found before, at a third of the way to the edge of Earth’s core”

“If it wasn’t down there, we would all be submerged,” says Steve Jacobsen at Northwestern University in Evanston, Illinois. Northwestern geophysicist Steve Jacobsen and his team made the discovery. “This implies a bigger reservoir of water on the planet than previously thought.” Scientists have found deep pockets of magma located about 400 miles beneath North America, a likely signature of the presence of water at these depths. It looks like water from the Earth’s surface can be driven to such great depths by plate tectonics, eventually causing partial melting of the rocks found deep in the mantle.

“Geological processes on the Earth’s surface, such as earthquakes or erupting volcanoes, are an expression of what is going on inside the Earth, out of our sight,” said Jacobsen. “I think we are finally seeing evidence for a whole-Earth water cycle, which may help explain the vast amount of liquid water on the surface of our habitable planet. Scientists have been looking for this missing deep water for decades.”

Read additionally “How we know what lies at Eath’s core” at BBC.

September 22, 2012 Catastrophe

According to newscientist.com it is midnight on September 22, 2012 and the skies above Manhattan are filled with a flickering curtain of colorful light. Few New Yorkers have seen the aurora this far south but their fascination is short-lived. Within a few seconds, electric bulbs dim and flicker, then become unusually bright for a fleeting moment. Then all the lights in the state go out. Within 90 seconds, the entire eastern half of the US is without power.

[youtube=”http://www.youtube.com/watch?v=0L9Arjmclz8″]

A year later and millions of Americans are dead and the nation’s infrastructure lies in tatters. The World Bank declares America a developing nation. Europe, Scandinavia, China and Japan are also struggling to recover from the same fateful event – a violent storm, 150 million kilometers away on the surface of the sun.

It sounds ridiculous. Surely the sun couldn’t create so profound a disaster on Earth. Yet an extraordinary report funded by NASA and issued by the US National Academy of Sciences (NAS) in January this year claims it could do just that.

Over the last few decades, western civilizations have busily sown the seeds of their own destruction. Our modern way of life, with its reliance on technology, has unwittingly exposed us to an extraordinary danger: plasma balls spewed from the surface of the sun could wipe out our power grids, with catastrophic consequences.

The projections of just how catastrophic make chilling reading. “We’re moving closer and closer to the edge of a possible disaster,” says Daniel Baker, a space weather expert based at the University of Colorado in Boulder, and chair of the NAS committee responsible for the report.

It is hard to conceive of the sun wiping out a large amount of our hard-earned progress. Nevertheless, it is possible. The surface of the sun is a roiling mass of plasma – charged high-energy particles – some of which escape the surface and travel through space as the solar wind. From time to time, that wind carries a billion-tonne glob of plasma, a fireball known as a coronal mass ejection. If one should hit the Earth’s magnetic shield, the result could be truly devastating.

The incursion of the plasma into our atmosphere causes rapid changes in the configuration of Earth’s magnetic field which, in turn, induce currents in the long wires of the power grids. The grids were not built to handle this sort of direct current electricity. The greatest danger is at the step-up and step-down transformers used to convert power from its transport voltage to domestically useful voltage. The increased DC current creates strong magnetic fields that saturate a transformer’s magnetic core. The result is runaway current in the transformer’s copper wiring, which rapidly heats up and melts. This is exactly what happened in the Canadian province of Quebec in March 1989, and six million people spent 9 hours without electricity. But things could get much, much worse than that.

Hurricanes Lessons.

There are a lot of information you can find now online about a current tropical cyclone Gustav that has intensified rapidly into a strong Category 1 Hurricane. It’s powerful natural phenomenon and not one to be trifled with. Many people who have lived in the area must leave their houses running away.

But what is Hurricane and where do they come from?
The study shows that the formation of hurricanes comes under the general heading of the formation of tropical cyclones, more properly known as “tropical cyclogenesis”. Musk (1988) has identified a list of factors which aid tropical cyclogenesis. The primary factor is the temperature of the sea, since this is where the hurricane derives most energy. So the origin of a hurricane is interaction warm ocean waters with rapidly cooling atmosphere therefore cyclones only occur in distinct seasons when the sea is warm enough.

. There are two ways of measuring hurricane energy; total energy released through cloud/rain formation; average hurricane produces 1.5cm/day of rain within a 665km radius. This would require 600 000 000 000 000 Watts of energy – 200 times the world’s electrical generating capacity Total kinetic energy of the wind; By complicated meteorological calculation, and using some very tricky maths, the average dissipation rate is about 1 500 000 000 000 Watts; equivalent to half the electrical generating capacity of the world.

So is it inevitable? Perhaps, yeas. Hurricanes are one of the most destructive natural hazards, both in terms of frequency and death toll. Very little can be done to stop a hurricane, because it has more power than all of the electrical capacity of the world. Even if all the nuclear weapons in the world were detonated simultaneously, they would only power a medium (Cat 2-3) hurricane for 6-12 hours.

Future of the Earth's Oceans.

Washington Post science writer Juliet Eilperin took part in a debate on the occasion of the future of the earth’s oceans and answered some interesting questions.

Eastern Market, D.C.: Juliet,
Having just seen “An Inconvenient Truth,” I am more than ever convinced that the unprecedented (and therefore unpredictable) melting of the Greenland and Antarctic ice caps present a clear and present (“present” here means possible within a decade, or a year!) danger to the world’s coastal cities. I would like to find out more on this, specifically on the models used to predict the sea level rise and the way it would actually play out on the continental margins. What’s a good, succinct source?

Juliet Eilperin: One of the scientists I talk to regularly who has studied this question is Michael Oppenheimer at Princeton University-he has written on the West Antarctic ice sheet and I’m sure you can find his work at www.princeton.edu. Konrad Steffan at the University of Colorado at Boulder is a Greenland ice sheet expert, so you can google him to look at his research. And you’re right, both these ice sheets could transform the planet if they melted.

Washington, D.C.: The announcement of the new “preserve” in the Pacific is tempered by the fact that the pro-whaling nations seem about to win their 20-year battle to reopen commercial whaling (scientific and small- to mid-scale commercial whaling were never banned). The “whales are plentiful” argument which Japan, Norway and Iceland have advanced seems to have been purchased with grant-payments to smaller countries in the Whaling Commission. Two questions:

1. Why has there been no press attention to the agonizing inhumanity of whaling (i.e., the animal takes several hours to die, during which time it is live-butchered, fully conscious), as opposed to mere availability statistics?

2. Will Japan, Norway and Iceland win?

Juliet Eilperin: So far we’ve seen a mixed message out of the International Whaling Commission: they voted against a move to secret ballots (which would have helped the pro-whaling camp) and in favor of a declaration backing the idea of returning the commission to the idea of a body that regulates commercial whaling. So stay tuned this week and I can give you a better idea in a couple of days of what’s happening on this.

Washington, D.C.: What do you believe are the most serious short-term threats to the ocean’s health and what, if anything, can the average person do about them?

Juliet Eilperin: Overfishing is the most serious short-term threat to the oceans. Boris Worm, a professor at Canada’s Dalhousie University, recently published a paper with several other researchers in which he wrote about the “roving banditry” of commerical fishing fleets, which rely on modern technology to just fish a population to collapse and then move onto the next target. This is not to say all commercial fishermen are irresponsible: many care about sustaining their livelihoods over the long term. The industry in Alaska, for example, has done a much better job of regulating itself than the New England fishing industry. So that’s the most serious immediate problem (global warming is the most serious long-term threat). And the best thing ordinary consumers can do is eat fish that’s sustainably caught, or get involved in the legislation that’s currently pending before Congress, the reauthorization of the Magnuson-Stevens Act. This is the law that regulates fishing in the United States.