Wednesday, May 16, 2007

Warming Triggers Alarming Retreat Of Himalayan Glaciers

Warming Triggers Alarming Retreat of Himalayan Glaciers


Glacial runoff in the Himalayas is the largest source of freshwater for northern India, and provides more than half the water to its most important river, the Ganges.

Glacial runoff also is the source of the headwaters for the Indus River in Pakistan, the Brahmaputra that flows through Bangladesh, the Mekong that descends through Southeast Asia, the Irrawaddy in Burma, and the Yellow and Yangtze rivers of China.

Scientists say 1.3 billion people reside in areas affected by glacial retreat, either in flood-prone areas or in locales that rely on year-round supplies of fresh water from glaciers rather than from the monsoon rainfall of only three or four months.

The retreating glaciers are occurring across an area that's the largest high-altitude land mass on the planet, bordered by the Himalayas to the south, the Tian Shan range to the north, and the Pamirs and the Karakorum mountains to the west.

Throughout the area, experts say, dwindling glaciers may lead to unstable mountainsides, greater sedimentation in rivers and disrupted irrigation systems, in addition to threatening water supplies to large populations.

China issued its first ever report on climate change in late December, saying average temperatures will rise two to three degrees Fahrenheit by 2020 and up to 6.4 degrees by the end of the century, unleashing more frequent "extreme weather events."

Scientists say glacial retreat will bring a feast-or-famine cycle to the Himalayas.

In the near term, accelerated glacial melting will bring a bonanza of water flow, perhaps even intense flooding, with great impact on biodiversity.

"The flooding events will scour the species that live in the river areas," said Dr. Lara Hansen, chief scientist for the global climate change program at the World Wildlife Fund. High-altitude plants and animals that are highly dependent on the glacial melt during the non-rainy season also will be affected, she added.

As climate change intensifies, she said, humans growing desperate for year-round water are likely to pay less attention to the needs of protecting biodiversity.

Small villages in Nepal, Bhutan, India and Pakistan that rely on glacier-fed water "are already feeling the pinch of this," Kulkarni said.

Far from the highest peaks in Tibet, large lakes fed by glacial runoff are rising by as much as 30 feet, experts said, submerging new areas and displacing some nomads. Experts say permafrost, or perennially frozen ground, is also beginning to melt.

"Sometimes when we camp out, we see water seeping up from the tent floor," said Bendo, a senior engineer with Remote Sensing Application Research Center of the Tibet Autonomous Region, who goes by only one name.

The Himalayas, with 17 percent glacial cover, have far more extensive glaciers than other ranges, such as the Alps, which have only a 2 percent cap of glacier and icepack.

End of excerpt

Photo Slideshow/The Roof Of The World Is Melting

Sunday, May 13, 2007

Southwest Water Woes

A bleached "bathtub ring," the result of a six-year drought that has dramatically dropped the level of the reservoir, shows on red Navajo sandstone formations near Last Chance Bay at Lake Powell near Page, Ariz. Lake Powell and the next biggest Colorado River reservoir, the nearly 100-year-old Lake Mead, are at the lowest levels ever recorded.
David Mcnew / Getty Images

Southwest Water Woes

You can listen to the radio program at a link at the original link noted above. Here is part of the transcript:

There’s been a drought in the Southwestern U.S. since 1998, but that hasn’t stopped the population in the region from rising by a million people per year. Brian Mann reports on the Colorado River’s struggle to meet growing water demands in the Southwest:

CURWOOD: It's Living on Earth. I'm Steve Curwood. Every day, it seems, thousands of Americans pack up for the sunny skies of the Southwest, especially the booming cities of Las Vegas and Phoenix. The Southwest is a desert, of course, but thanks to the massive water projects of the 1930's it became hospitable for millions of settlers. But now there's trouble in the Southwest. The region is suffering through its eighth year of drought with little or no relief in sight. For much of its water the Southwest relies on the Colorado River to brings snowmelt from the Rocky Mountains. But snow patterns are changing and the Colorado is carrying a lot less water than it did a century ago. Overall it seems global warming is hitting the region harder than just about anywhere else in the country

Brian Mann of North Country Public Radio has our story.


MANN: Seventy-five years later, big crowds of tourists squeeze through the dam's visitor center.

ANNOUNCER: Come on in, folks, Find a place where you can see!

MANN: This may be one of the world's modern engineering marvels. But tour guide Bruce Laughlin, who works for the Federal Bureau of Reclamation, acknowledges that the Colorado River's great reservoirs -- at Lake Powell and here at Lake Mead -- were built for much wetter times. For nearly a decade, they've been drying up.

LAUGHLIN: I think we're about 54%.

TOURIST: How long since it's been full?

LAUGHLIN: This lake was filled right to the top before this drought started in 1998. This coming year, they're going to hold as much water as they can in the upper lake because they need to fill up Lake Powell, because it's getting dangerously low. This lake's probably gonna go down more.

MANN: Scientists now believe that the West was settled during an unusually wet period. The people who built these reservoirs had unrealistic expectations for how much rain and snow would fall each year. Recent climate models predict further drying, less precipitation for the Southwest.

GLEICK: If nature gives us a little less water, then there just is not enough to go around.

MANN: Peter Gleick is a water expert at an environment and resources think tank in Oakland, California called the Pacific Institute.

GLEICK: It turns out that a very small decrease in average flow of the Colorado, in the long run, drains those reservoirs dry.

MANN: A new study by the Lamont-Doherty Earth Observatory at Columbia University -- published in the journal Science -- focused on predictions for the Southwest. Atmospheric scientist and lead researcher Richard Seager says he expects precipitation in the region to drop by 10-20 percent before mid-century. Meanwhile the population of the Southwest is still growing by roughly a million people a year.

SEAGER: With declining water availability there's going to be quite a tussle about who gets the water and whether it's going to be possible to reallocate water in a way that will retain agriculture that's needed, but also sustain a growing urban population.

MANN: Rising temperatures are already shrinking the mountain snow pack, which feeds Western rivers through the summer. In the future, by summer's end, there may be no more snow to melt.

SEAGER: So that natural system of water storage that the water supply system is relying on is going to become less effective.

MANN: Water experts say these incremental changes could disrupt the Colorado River's complicated system of dams, reservoirs and allocation treaties that now supply water to 25 million people.

MULROY: What resources we do have, given what global warming could present to us, could evaporate tomorrow.

MANN: Patricia Mulroy is general manager of the Southern Nevada Water Authority, which is charged with supplying water to the city of Las Vegas.

MULROY: I do believe that the Colorado River is going to be severely challenged as we go through global warming. We're already behind in developing those alternatives on how to protect human existence in the West.

MANN: Conservation is a necessity. And some fast-growing cities have implemented water-use restrictions unheard of in water-rich parts of the U.S. Denver and Aurora, Colorado are seen as models -- as is Tucson, Arizona. Here in Las Vegas, there are actually water detectives, who sniff out waste.


MANN: The Water Authority has combined this kind of enforcement with new incentives, urging people to convert from grass and shrubs to desert plants and rock gardens. But critics say the city isn't doing nearly enough. Down on Vegas's casino strip, there is water everywhere -- flowing from extravagant fountains, gushing over manmade waterfalls.


MANN: Outside the Venetian, one of Vegas's showcase casinos, gondolas ferry tourists through glittering canals. This water is re-circulated and reused, but Jill Rowland-Legan says it's a symbol of the city's outdated thinking.

LEGAN: Are they being smart about growth? Should they have some type of moratorium on growth until we get this water issue taken care of? Are they still catering to the major casinos and the major contractors?

MANN: Jill Rowland-Legan heads the chamber of commerce in Boulder City, a small town that lies between Las Vegas Vegas and the Lake Mead reservoir. Her community has embraced a slow-growth ordinance that limits new home construction.

LEGAN: We don't even take our complete allocation of water here in Boulder City because it's all going to Vegas to make sure that they're taken care of.

MANN: But Patricia Mulroy, with the Southern Nevada Water Authority, says slowing Las Vega's growth is not an option. Construction cranes punctuate the horizon. With eight thousand new residents arriving every month, neighborhoods push steadily toward the arid hills.

MULROY: Every piece of private land is acquired with an expectation to not leave it desert, but to build on it. And the private property owner has a right to develop his property.

MANN: Eighty percent of the Colorado River's water is still used for agriculture and Mulroy says that has to change. The Water Authority has already begun buying up farms and ranches in rural Nevada, in a bid to control more water rights.

But as the drought deepens, Columbia University researcher Richard Seager says rain and snowfall in this region will decline to levels not experienced since the Dust Bowl of the 1930s. Only this time, the dry spell won't end.

SEAGER: That level of reduction was enough to cause really severe trouble and that level of reduction persisting for an even longer period of time will equally cause a lot of trouble.

For Living On Earth I'm Brian Mann in Las Vegas, Nevada.
It is always the same. People moving to the desert to swim in their pools, water their desert lawns, and live a life in excess not thinking about the future. Well, the future is here and it isn't looking so good unless those people wake up and think about something other than themselves. It sometimes is as simple as that.

Weather patterns are changing and temperatures are warming due to the climate crisis we face. That means as we are seeing, that snowpack that feeds the rivers will be no more if the current level is sustained and what is left will have to be allocated amicably and equitably with a rising population. Just how do people propose that will happen without tensions? How will people be able to live with most of the water being used in agriculture? You think what has happened in Australia can't happen here in the U.S.? Think again. It has already started.

Scientists Predict Southwest Mega Drought

WASHINGTON - Changing climate will mean increasing drought in the American Southwest — a region where water already is in tight supply — according to a new study.

“The bottom line message for the average person and also for the states and federal government is that they’d better start planning for a Southwest region in which the water resources are increasingly stretched,” said Richard Seager of Columbia University’s Lamont Doherty Earth Observatory. Seager is lead author of the study published online Thursday by the journal Science.

Researchers studied 19 computer models of the climate, using data dating back to 1860 and projecting into the future, to the year 2100. The same models were used in preparing the reports of the Intergovernmental Panel on Climate Change.

The consensus of the models was that climate in the southwestern United States and parts of northern Mexico began a transition to drier conditions late in the 20th century and is continuing the trend in this century, as climate change alters the movement of storms and moisture in the atmosphere. The models show the drying trend continuing all the way to 2100 — for more than 90 years.

"If these models are correct, the levels of aridity of the recent multiyear drought, or the Dust Bowl and 1950s droughts, will, within the coming years to decades, become the new climatology of the American Southwest," the researchers wrote.

In a telephone interview, Seager said that doesn’t mean there would be dust storms like those of the 1930s Dust Bowl, because conditions at that time were also complicated by poor agricultural practices. But he said the reduction in rainfall could be equivalent to those times when thousands of farmers abandoned their parched land and moved away in search of jobs.
Currently, the majority of water in the Southwest is used in agriculture, but the urban population of the region is growing and so the water needs of people are growing as well, he explained.

“So, in a case where there is a reduced water supply, there will have to be some reallocation between the users,” Seager said. “The water available is already fully allocated.” He said feels that adjustments can be made to deal with the change, perhaps by withdrawing some land from production and by conserving water in urban areas. “But it’s something that needs to be planned for,” Seager said. “It’s time to start thinking how to deal with that.”

Jonathan T. Overpeck, director of the Institute for the Study of Planet Earth at the University of Arizona, said the finding “agrees with what is already happening in the Southwest, and will be further complicated by the already declining spring snowpack due to warming.”

“These are scary results, but scary in part because they are results of well thought-out scientific work by a large number of strong scientists,” said Overpeck, who was not part of the research team.

Another World Water Day Gone

We see another World Water Day pass us by. The theme, Water For All, signifies that though some progress has been made we are woefully behin...