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Posts Tagged ‘temperature’

Giant ocean whirlpools puzzle scientists

April 13, 2011 Comments off

pravda

US scientists discovered two giant whirlpools in the Atlantic Ocean, off the coast of Guyana and Suriname. It became a sensational discovery because this part of the ocean has been studied thoroughly, and no one expected anything like that to appear in the area. More importantly, no one can understand where the whirlpools came from and what surprises they may bring to people.

According to Brazilian scientist Guilherme Castellane, the two funnels are approximately 400 kilometers in diameter. Until now, these were not known on Earth. The funnels reportedly exert a strong influence on climate changes that have been registered during the recent years.

“Funnels rotate clockwise. They are moving in the ocean like giant frisbees, two discs thrown into the air. Rotation occurs at a rate of one meter per second, the speed is Read more…

Earth’s Core Provides Climate Insights

March 14, 2011 Comments off

 

Summary: By studying the molten core of the planet Earth, scientists have uncovered new evidence that humans play a dominant role in changing Earth's climate. The study could have important implicaitons in understanding the future of life on our planet.

 

The latest evidence of the dominant role humans play in changing Earth’s climate comes not from observations of Earth’s ocean, atmosphere or land surface, but from deep within its molten core.

Scientists have long known that the length of an Earth day – the time it takes for Earth to make one full rotation – fluctuates around a 24-hour average. Over the course of a year, the length of a day varies by about 1 millisecond, getting longer in the winter and shorter in the summer. These seasonal changes in Earth’s length of day are driven by exchanges of energy between the solid Earth and fluid motions of Earth’s atmosphere (blowing winds and changes in atmospheric pressure) and its ocean. Scientists can measure these small changes in Earth’s rotation using astronomical observations and very precise geodetic techniques.

But the length of an Earth day also fluctuates over much longer timescales, such as interannual (two to 10 years), decadal (approximately 10 years), or those lasting multiple decades or even longer. A dominant longer timescale mode that ranges from 65 to 80 years was observed to change the length of day by approximately 4 milliseconds at the beginning of the Read more…

Earth May be Uninhabitable for Future Generations

January 19, 2011 Comments off

Humans are in danger of making large parts of the Earth uninhabitable for thousands of years because of man made climate change, according to new evidence based on geological records.

The US study predicted that if society continues burning fossil fuels at the current rate, atmospheric levels of carbon dioxide could rise from the current level of 390 parts per million (ppm) to 1,000 by the end of this century.

The last time the world had such high levels of carbon dioxide temperatures were on average 29F(16C) above pre-industrial levels. Evidence has been found of crocodiles and palm trees at the Poles and only small mammals were able to survive.

Jeffrey Kiehl, of the National Center for Atmospheric Research (NCAR), who carried out the study, said the Earth could return to such temperatures over hundreds or even thousands of years.

But unlike last time, when it happened over millions of years, temperatures will rise too fast for species to adapt and change.

In the short term he said temperatures could rise by more than 10.8F (6C) by the end of the century, which will also wipe out species.

“This is happening at such a rate how will species, including humans, respond? The implications for the biosphere is of great concern.”

Dr Kiehl not only looked at geological records but also computer models to predict what will happen if carbon dioxide levels rise at such a rate.

He included ‘feed back factors’, such as melting sea ice, methane released from thawing permafrost and Amazon die-back.

This showed that temperatures will increase much faster than previously thought as a result of rising carbon dioxide.

“If we don’t start seriously working toward a reduction of carbon emissions, we are putting our planet on a trajectory that the human species has never experienced,” he said. “We will have committed human civilization to living in a different world for multiple generations.”

Dr Kiehl hit back at critics who claim that acting on climate change by reducing the use of fossil fuels will upset the world order.

“A truly conservative position is to conserve what we have, to not radically change things and if we do not want to radically change the environment then the conservative approach is to conserve the Earth as the human species has known it ever since we have been around on this planet.”