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Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 20 Sep 2011
Earth’s deep oceans may absorb enough heat at times to flatten the rate of global warming for periods of as long as a decade–even in the midst of longer-term warming. This according to a new analysis led by scientists at the National Center for Atmospheric Research (NCAR).
 Excess energy entering the climate system due to greenhouse gas increases may not be immediately realized as warmer surface temperatures, as it can go into the deep ocean instead The study, based on computer simulations of global climate, points to ocean layers deeper than 1,000 feet as the main location of the “missing heat” during periods such as the past decade when global air temperatures showed little trend.
The findings also suggest that several more intervals like this can be expected over the next century, even as the trend toward overall warming continues.
“We will see global warming go through hiatus periods in the future,” says NCAR’s Gerald Meehl, lead author of the study.
“However, these periods would likely last only about a decade or so, and warming would then resume. This study illustrates one reason why global temperatures do not simply rise in a straight line.”
The research, by scientists at NCAR and the Bureau of Meteorology in Australia, was published online Sunday in Nature Climate Change.
Funding for the study came from the National Science Foundation (NSF), NCAR’s sponsor.
“The research shows that the natural variability of the climate system can produce periods of a decade or more in which Earth’s temperature does not rise, despite an increase in greenhouse gas concentrations,” says Eric DeWeaver, program director in NSF’s Division of Atmospheric and Geospace Sciences. Continue reading Missing energy is buried in the ocean
Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 29 Aug 2011
The severe drought in the Horn of Africa, which has caused the death of at least 30 000 children and is affecting some 12 million people, especially in Somalia, is a direct consequence of weather phenomena associated with climate change and global warming, environmental scientists say.
 The intensification of La Niña will see growing desertification in Africa. Photo UNCCD. “The present drought in the Horn of Africa has been provoked by El Niño and La Niña phenomena in the Pacific Ocean, which unsettle the normal circulation of warm and cold water and air, and dislocate the humidity conditions across the southern hemisphere,” Friedrich-Wilhelm Gerstengarbe, senior scientist at the German Potsdam Institute for Climate Impact Research (PIK, after its German name), told IPS.
Both phenomena are a part of the southern oscillation climate pattern that occurs across the tropical Pacific Ocean every five to seven years. It is characterised by variations in the temperature of the surface of the tropical eastern Pacific – warming or cooling known as El Niño and La Niña respectively – and a changing air surface pressure in the western Pacific. Continue reading Climate change intensifies El Niño and La Niña
Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 08 December 2010
The once-vibrant coral reef shielding these sun-soaked beaches from the wrath of the sea is withering away under the stress of pollution and warmer water.
 Coral bleaching - a “hideous” sight for veteran scuba divers It’s not likely to get much help from world governments meeting in Cancun for talks on a new climate pact. Their so-far elusive goal to limit global warming to 2 degrees C (3.6 F) is too little too late, says coral expert Roberto Iglesias.
“That represents the end of the coral reefs in the world,” says the Mexican scientist, who works at a marine research station in Puerto Morelos, about 20 kilometres south of the beach resort hosting the annual UN climate conference.
Coral reefs are like underwater jungles that host 25 percent of marine species and provide food and income to hundreds of millions of people, mostly in the developing world. They also serve as shock absorbers to storm surges whipped up by hurricanes.
But many reefs, including the one off this hotel-packed coastline, have been damaged by water pollution and overfishing, leaving them vulnerable to a warming ocean that “bleaches” corals and sometimes kills them, Iglesias said.
This year, preliminary reports show global coral bleaching reached its worst level since 1998, when 16 percent of the world’s reefs were killed off, said Mark Eakin, a coral reef specialist at the US National Oceanic and Atmospheric Administration.
“Clearly, we are on track for this to be the second worst (bleaching) on record,” he said. “All we’re waiting on now is the body count.” Continue reading On track for the second worst coral bleaching on record
Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 24 November 2010
What could be the worst drought on record has hit the Amazon region, and is the third extreme drought in the last 12 years.
The Rio Negro reached an all time low in [...]
Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 12 October 2010
 The arid soil of the Karoo bursts into life after the first rains The soils in large areas of the Southern Hemisphere, including major portions of Australia, Africa and South America, have been drying up in the past decade, a group of researchers conclude in the first major study to ever examine “evapo-transpiration” on a global basis.
Most climate models have suggested that evapo-transpiration, which is the movement of water from the land to the atmosphere, would increase with global warming. The new research, published online in the journal Nature, found that’s exactly what was happening from 1982 to the late 1990s.
But in 1998, this significant increase in evapo-transpiration – which had been seven millimetres per year – slowed dramatically or stopped.
In large portions of the world, soils are now becoming drier than they used to be, releasing less water and offsetting some moisture increases elsewhere.
Due to the limited number of decades for which data are available, scientists say they can’t be sure whether this is a natural variability or part of a longer-lasting global change. But one possibility is that on a global level, a limit to the acceleration of the hydrological cycle on land has already been reached.
If that’s the case, the consequences could be serious. They could include reduced terrestrial vegetation growth, less carbon absorption, a loss of the natural cooling mechanism provided by evapo-transpiration, more heating of the land surface, more intense heat waves and a “feedback loop” that could intensify global warming.
“This is the first time we’ve ever been able to compile observations such as this for a global analysis,” said Beverly Law, a professor of global change forest science at Oregon State University. Law is co-author of the study and science director of the AmeriFlux network of 100 research sites, which is one major part of the FLUXNET synthesis that incorporates data from around the world.
“We didn’t expect to see this shift in evapo-transpiration over such a large area of the Southern Hemisphere,” Law said. “It is critical to continue such long-term observations, because until we monitor this for a longer period of time, we can’t be sure why this is occurring.” Continue reading Global soils are drying
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