Sunday, July 11, 2010

A fiery beginning to the end of an empire

Friday, July 09, 2010

Murali the best of his generation - Saqlain Mushtaq

Tuesday, July 06, 2010

Via: Medical Coding Certification

http://www.thisblogrules.com/2010/07/facts-about-the-internet-infographic.html#

gapingvoid cartoon #120 'Good For You' July 5, 2010

Sunday, July 04, 2010

Extraordinary map reveals Earth's gravity field for the first time

It is one of the most fundamental and mysterious forces in the Universe.

But this is the first glimpse of what the gravity field which surrounds the Earth looks like in a unique map created be a sophisticated European satellite.

The map is known as a geoid - an imaginary global ocean dictated by gravity in the absence of tides and currents.

It was first described almost 200 years ago but this is the first time it has been mapped in real-time.

Earth's gravity field as captured by the GOCE satellite gives an unprecedented view of how the force acts on our planet. The differences in gravitational force are represented using colours that show -100 metres up to 100 metres.

Gravity does not exert an equal force everywhere on Earth. Factors such as the rotation of the planet, the effects of mountains and density variations in Earth’s interior mean that this fundamental force is not quite the same all over.

The extraordinary map will be used to measure ocean circulation, sea-level change and ice dynamics.

'GOCE is delivering where it promised: in the fine spatial scales,' GOCE Mission Manager Rune Floberghagen said.

'We have already been able to identify significant improvements in the high-resolution 'geoid', and the gravity model will improve as more data become available.'

ESA launched GOCE in March 2009 to map Earth's gravity with unprecedented accuracy and resolution.

The model, based on only two months of data, from November and December 2009, shows the excellent capability of the satellite to map tiny variations in Earth’s gravity.

GOCE’s final gravity map and geoid will be used in geophysics and surveying to oceanography and sea-level research.

Dr Floberghagen added.' Over continents, and in particular in regions poorly mapped with terrestrial or airborne techniques, we can already conclude that GOCE is changing our understanding of the gravity field.'

'Over major parts of the oceans, the situation is even clearer, as the marine gravity field at high spatial resolution is for the first time independently determined by an instrument of such quality.'

Chairman of the GOCE Mission Advisory Group, Prof. Reiner Rumme said: 'With each two-month cycle of data, the gravity model will become more detailed and accurate. I am convinced that the data will be of great interest to various disciplines of Earth sciences.'

The satellite was designed to orbit at a very low altitude because gravitational variations are stronger closer to Earth.

Since mid-September 2009, GOCE has been in its gravity-mapping orbit at a mean altitude of just 254.9 km – the lowest orbit sustained over a long period by any Earth observation satellite

Air at this low altitude causes the orbit of a standard satellite to decay very rapidly. But GOCE nullifies the drag by firing an ion thruster using xenon gas to boost its orbit.

It ensures the gravity sensors are flying as though they are in pure freefall, so they pick up only gravity readings and not the disturbing effects from other forces.

To obtain clean gravity readings, there can be no disturbances from moving parts, so the entire satellite is a single extremely sensitive measuring device.

Largest Jaws

Monster of the Deep: Scientists find fossil skull of 43ft long whale which had 14in teeth

A new species of 'killer' sperm whale with fearsome teeth that roamed the seas more than 12 million years ago has been discovered by scientists.

The fossilised skull and jaw of the gigantic creature, which was 43ft long with a 10ft head, were found off the coast of Peru.

It is believed the creature would have preyed on other whales as it boasted 14in teeth.

Predator: The Leviathan melvillei would have attacked and killed other large whales, according to scientists

Dubbed Leviathan Melvillei –after Herman Melville the author of the fictional Moby Dick – it has been described in the journal Nature as the largest fossil sperm whale ever found.

In terms of size and appearance, it would have been much like a modern whale – however, Leviathan would have been an aggressive predator, unlike today’s creatures.

While now the whales they have a big bite, their teeth are relatively small and are restricted to the lower jaw - and they feed by suction.

But Dr Olivier Lambert, of the Natural History Museum, in Paris, said the fossil’s jaw had huge teeth on both sides, giving it the biggest bite ever to kill prey up to 26ft long.

'Sea monster': Three lower teeth (a,b,c) of Leviathan melvillei compared to teeth of the modern sperm whale

Dr Lambert said: ‘This sperm whale could firmly hold large prey with its interlocking teeth, inflict deep wounds and tear large pieces from the body of the victim.

‘With their large size and robust jaws, Leviathan adults were surely free from predation.

‘It was a kind of sea monster.

‘And it’s interesting to note that at the same time in the same waters was another monster, which was a giant shark about 15 metres long. It’s possible they may have fought each other.’

Anthony Friscia, a paleontologist at the University of California, Los Angeles said scattered finds of huge fossilised teeth had long hinted at the ancient whale's existence.

But without a skull to fit them in, the creature's shape, size and feeding habits remained a mystery.

'The fact that they have found the entire jaw - well, almost the entire skull - is what's pretty unprecedented,' he said.

The ancient beasts 'were the killer whales of their time, although on a much grander scale,' Friscia said. 'They were close to the biggest things around.'

The Natural History Museum in Rotterdam will exhibit reconstructions of the sea monster later this year.

Discovery: The fossil was found by researchers in the Pisco-Ica desert, Peru

Casts of the three largest teeth are on display now.

The three-metre fossilised skull was discovered by researchers in southern Peru in 2008.

The unique fossil will remain in Peru, in the collection of the Natural History Museum in Lima.

Dr Lambert and colleagues said: 'This sperm whale could firmly hold large prey with its interlocking teeth, inflict deep wounds and tear large pieces from the body of the victim, as performed on a smaller scale by the delphinid Orcinus, the main modern meat-eating cetacean.'

'The killer whale (Orcinus orca), commonly referred to as the orca - and, less commonly, blackfish - is the largest species of the oceanic dolphin family.

'It has been reported occasionally to cooperatively attack and kill most of the large baleen whale species and sperm whales, as well as smaller fish and seabirds.'

The researchers, whose findings are published in Nature, added: 'With their large size and robust jaws, Leviathan adults were surely free from predation.'

The sperm whale (Physeter macrocephalus) that now roams our oceans has a totally different choice of food and way of feeding.

It feeds on squid that are taken by suction feeding at great depths. This modern sperm whale has smaller teeth in the lower jaw with the upper jaws being practically toothless.

Sperm whales have huge brains that weigh about 20 pounds, the largest of any animal.

It is estimated there are about 200,000 world-wide and they are now considered an endangered species.

These whales, and many other large whales, were over-hunted for many years, since their meat, oil, and other body parts are very valuable.

Since whale hunting has decreased in the last few decades, their populations are starting to recover

Man's impact on world's water supply

Revealed: Shocking satellite images of lakes show extent of man's impact on world's water supply

These dramatic before-and-after satellite photos show the terrifying effect man is having on the world's resources.

Taken over nearly 40 years, photographs show the drying up of several bodies of water around the world - receding as mankind's demand for water grows.

Included in the shocking collection is the once mighty Aral Sea in Central Asia.

The expanse of water, like several others across the globe, has been reduced to worryingly sparse levels. In April the situation at the Aral Sea was described as 'one of the planet's worst environmental disasters' by UN Secretary General Ban Ki-Moon.

1973: Satellite image of the Aral Sea used to be the fourth largest lake in the world

1999: More than 25 years on the sea has noticeably shrunk to less than half its size

2009: Satellite image taken last year shows a situation described as 'one of the planet's worst'

Shown here in images taken from space between 1973 and 2009, slowly but surely the Aral - in fact a salt water lake - has shrunk from being the size of Ireland to a cluster of contaminated ponds.

An inland lake, the Aral is found between Uzbekistan and Kazakhstan and used to be the fourth largest lake in the world. Since the 1960s, it has lost more than half of its volume.

The drying is due to overuse of the lake's feeder rivers. In the 1960s the former Soviet Union diverted the Syr Darya and Amu Darya for the irrigation of cotton and paddy fields.

Now 50 years later the water is at a dismal 10 per cent of its level when the projects first began.

So great was the impact on the region the local climate was thought to have changed and pollution has risen to dangerous levels.

The destruction of the lake has also decimated the local fishing industry, causing severe knock-on unemployment and further economic woe for the people living around it.

Across the globe once rich and fertile lands are facing the same catastrophe.

Arid and desolate Iraq was once a green, lush environment even reputed to be the setting of the Garden of Eden.

Seen from above between 1973 and 2000 the Mesopotamia marshlands straddle the borders between Iraq and Iran near the mighty Tigris and Euphrates rivers.

1990: Satellite image of drained areas (grey) amongst marshland (dark red) around the Tigris and Euphrates rivers in Iraq. Darker areas show deep water

2000: The same image shows how dramatically the water has receded in just 20 years. The rivers were drained to provide agricultural land

The marshes were systematically drained in the mid- to late 20th century. This was done to provide agricultural land, but also to destroy the habitat of the Shi'a Muslim Marsh Arabs, who were persecuted by the Iraqi ruling Ba'athist Party.

Also included in the before-and-after pictures are the Toshka Lakes, in southern Egypt.

They were formed in the 1990s by diverting water from Lake Nasser, an artificial lake formed behind the Aswan High Dam on the river Nile.

The region was planned to be a major new agricultural and industrial site for Egypt. But as these images show, the region is drying fast.

One image taken in March 2001, shows the lakes near their maximum capacity. A later satellite picture from December 2005 shows how the waters receded due to drought and rising demand for water, leaving a ring of brown wetlands around the edges of the lakes.

Lake Chad, located in the Sahel region near the Sahara, was the fourth largest lake in Africa in the 1960s and had an area of more than 10,000 square miles.

But by the 21st century it had shrunk to less than 600 square miles - around a twentieth of its size. This was caused by increased use of irrigation combined with severe droughts.

The Toshka Lakes in southern Egypt were formed in the 1990s by diverting water from Lake Nasser, an artificial lake that formed behind the Aswan High Dam on the river Nile.

The region was planned to be a major new agricultural and industrial site for Egypt but as these images show - between 2001 and 2005 - the region is drying fast.

The waters have receded, leaving a ring of brown wetlands around the edges of the lakes, because of drought and a rising demand for water in the area.

Dr Benjamin Lloyd-Hughes of the Walker Institute for climate system research, University of Reading, said: 'Ultimately the disaster seen at the Aral Sea and the marshes are the combined effects of man and rising temperatures in those regions.

'There has not been much change in rainfall in those areas but the temperature has risen by over 1 degree Centigrade since 1970, which will have enhanced losses due to evaporation.

'Pollution in the area will have become worse because as the water evaporates, pollutants in the water become more concentrated and less diluted.'

At Lake Chad and the Toshka Lakes the same effect of man in combination with climate change has been observed.

Dr Lloyd-Hughes added: 'There has been a 30% reduction in annual rainfall since 1900 in these regions but not a significant change in temperature.

'Reductions in lake levels here seem to driven by reductions in rainfall rather than increased evaporation.

'The outlook is that there will be no change in rainfall but temperature could increase by another two degrees Centigrade by 2100. This is not good but not so bad as for the Aral Sea and Mesopotamia.

'Global warming is a problem that is happening everywhere but if drought is happening in your region then it is a far greater problem.'

With the growth of mass-agriculture to feed a severely ballooning global population, water demand has begun to perilously outstrip supply, making disasters like the Aral Sea a grim and alarming likelihood for the future.

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