Rice production at risk from rising temperatures
Source MANILA - A projected rise in temperatures due to climate change will slow rice production in Asia, an international team of scientists said in a new study.
The study, published on Monday in the peer-reviewed journal of the United States-based National Academy of Sciences, claimed that rising temperatures during the last 25 years have already cut the rice yield growth rate by 10 to 20 per cent in several parts of Asia.
A decline in rice production means that more people will slip into poverty and hunger, the researchers said. Around three billion people eat rice every day and more than 60 per cent of the world's one billion poorest and undernourished people in Asia depend on rice as their staple, according to the Philippine-based International Rice Research Institute.
"If we cannot change our rice production methods or develop new rice strains that can withstand higher temperatures, there will be a loss in rice production over the next few decades as days and nights get hotter," Mr Jarrod Welch, lead author and graduate student of economics at the University of California, San Diego, wrote in the study.
Scientists believe global greenhouse gas emissions must be cut in half by mid-century to keep the Earth's average temperature from rising more than 2°Celsius above the levels that existed before nations began industrialising in the late 18th century. AP
=====================================================The study, published on Monday in the peer-reviewed journal of the United States-based National Academy of Sciences, claimed that rising temperatures during the last 25 years have already cut the rice yield growth rate by 10 to 20 per cent in several parts of Asia.
A decline in rice production means that more people will slip into poverty and hunger, the researchers said. Around three billion people eat rice every day and more than 60 per cent of the world's one billion poorest and undernourished people in Asia depend on rice as their staple, according to the Philippine-based International Rice Research Institute.
"If we cannot change our rice production methods or develop new rice strains that can withstand higher temperatures, there will be a loss in rice production over the next few decades as days and nights get hotter," Mr Jarrod Welch, lead author and graduate student of economics at the University of California, San Diego, wrote in the study.
Scientists believe global greenhouse gas emissions must be cut in half by mid-century to keep the Earth's average temperature from rising more than 2°Celsius above the levels that existed before nations began industrialising in the late 18th century. AP
Extreme weather fuels debate over global warming
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PARIS (AFP) - – As Russia battles wildfires triggered by an unprecedented heatwave, flood waters surge across a drenched Pakistan leaving millions of people homeless, and questions are asked about global warming.
Extreme weather has been a feature of the summer of 2010, with floods in Pakistan, China and Eastern Europe seemingly matched by heatwaves in Western Europe and Russia.
However, experts interviewed by AFP Monday were cautious over offering the events as proof of a changing climate, saying that while they fit with climatic projections in a warming planet, one extremely dry -- or wet -- summer isn't sufficient evidence in isolation.
"One cannot conclude 100 percent that nothing like this has happened in the past 200 years, but the suspicion is there. Even if it's only a suspicion," said Jean-Pascal van Ypersele, vice-president of the Intergovernmental Panel on Climate Change (IPCC), which has tracked the impact of human activity on climate for the past 20 years.
"These are events which reproduce and intensify in a climate disturbed by greenhouse gas pollution," he said.
"Extreme events are one of the ways in which climatic changes become dramatically visible."
The planet has never been as hot as it has been in the first half of this year, the US National Oceanic and Atmospheric Administration said in a July report.
According to the IPCC, droughts and heatwaves likes those affecting Russia and 18 US states become longer and more intense in a warming planet.
"Whether in frequency or intensity, virtually every year has broken records, and sometimes several times in a week," said Omar Baddour, who tracks climate change for the World Meteorological Organisation.
"In Russia, the record temperature in Moscow (38.2 degrees Celsius, 100.8 degrees Farenheit in late July) -- which had not been seen since records began 130 years ago -- was broken again at the start of August. In Pakistan, the magnitude of the floods is unheard of," he said.
"In both cases, it is an unprecedented situation. The succession of extremes and the acceleration of records conform with IPCC projections. But one must observe the extremes over many years to draw conclusions in terms of climate," he said.
The floods in Pakistan could be caused by La Nina -- the inverse of the El Nino phenomenon, which it generally follows -- namely the cooling of surface temperatures in the Pacific ocean, Baddour said.
"In general, El Nino leads to drought in the Indian subcontinent and the Sahel. With La Nina, it is the opposite," said Baddour.
According to British climatologist Professor Andrew Watson, the high temperatures this summer are linked to last year's El Nino.
"We know that in a period following El Nino you got a very hot year globally and that is certainly occuring this year," he said.
Nevertheless, Watson said the extreme events are "fairly consistent with the IPCC reports and what 99 percent of the scientists believe to be happening."
Watson, who is from the University of East Anglia which was at the centre of last year's "climategate" scandal over faked data, was reluctant to leap to any conclusions.
"I'm quite sure that the increased frequency of these kind of summers over the last few decades is linked to climate change," he said
"But you cannot say a single event or a single summer is unequivocally due to climate change -- by definition it's weather, and not climate."
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Massive ice island breaks off Greenland glacier
Source
WASHINGTON (AFP) - – A massive ice island four times the size of Manhattan has broken off an iceberg in north-western Greenland, a researcher at a US university said.
Andreas Muenchow at the University of Delaware said in a statement Friday that the last time the Arctic lost such a large chunk of ice was in 1962.
Muenchow's research focuses on the Nares Strait, a region between far north-eastern Canada and northwestern Greenland, about 1,000 kilometers (620 miles) south of the North Pole.
Early on August 5, "an ice island four times the size of Manhattan was born in northern Greenland," said Muenchow.
The freshwater stored in the ice island could "keep all US public tap water flowing for 120 days," Muenchow said.
Satellite images of the area show that the Petermann Glacier lost about one-quarter of its 70 kilometer (43-mile) long floating ice-shelf.
The Petermann glacier is one of Greenland's two largest glaciers that end in floating shelves, and connects Greenland's ice sheet directly with the ocean.
Muenchow credits Trudy Wohlleben of the Canadian Ice Service with detecting the ice island early Thursday, hours after raw data from a NASA satellite was downloaded, processed, and analyzed at the university.
The ice island will enter Nares Strait, between northern Greenland and Canada, where it will run into small islands.
"The newly born ice-island may become land-fast, block the channel, or it may break into smaller pieces as it is propelled south by the prevailing ocean currents," said Muenchow.
The ice island could then head along the Canadian coast and reach the Atlantic within the next two years, he said.