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Earth’s poles are shifting because of climate change

“Climate change is causing the North Pole’s location to drift, owing to subtle changes in Earth’s rotation that result from the melting of glaciers and ice sheets.

Computer simulations had suggested that the melting of ice sheets and the consequent rise in sea level could affect the distribution of mass on the Earth’s surface. This would in turn cause the Earth’s axis to shift, an effect that has been confirmed by measurements of the positions of the poles.

Jianli Chen of the University of Texas at Austin and colleagues have shown that melting due to our greenhouse-gas emissions is making its own contribution to the shift. …”Ice melting and sea level change can explain 90 per cent of the [eastward shift],” says Chen. “The driving force for the sudden change is climate change.””


Greenland’s ice sheets are disappearing faster than anyone predicted

“Climatologist Jason Box has a radical theory why…

In 2009, he announced the Petermann glacier, one of the largest in Greenland, would break up that summer – a potent sign of how fast the Arctic was warming. Most glaciologists thought he was nuts – especially after the summer passed and nothing happened. In 2010, however, Petermann began to calve; two years later, it was shedding icebergs twice the size of Manhattan. Another example: In early 2012, Box predicted there would be surface melting across the entirety of Greenland within a decade. Again, many scientists dismissed this as alarmist claptrap. If anything, Box was too conservative – it happened a few months later. He also believes that the climate community is underestimating how much sea levels could rise in the coming ­decades.

…Box decided to return to Greenland this summer – his 24th trip here in the past 20 years – to test a more startling hypothesis, part of what he calls “a unified theory” of glaciology: that tundra fires in Canada, massive wildfires in Colorado and pollution from coal-fired power plants in Europe and China had sent an unexpectedly thick layer of soot over the Arctic region last summer, which settled onto Greenland’s vast frozen interior, increasing the amount of sunlight the snow and ice absorbed, which in turn accelerated the melting.”

Report warns of drastic glacier shrinkage in China

2010.10.08 – Original Source: Xinhua

The average area of glaciers in western China might shrink by about 30 percent by 2050 because of global warming, damaging crop production and worsening droughts.

The dire prediction came Friday in a report released at the UN climate talks in north China’s Tianjin Municipality.

The “Climate Changes and Poverty — Case Study in China” report was jointly released by organizations including the Institute of Environment and Social and Sustainable Development in Agriculture with the Chinese Academy of Agricultural Sciences.

Forecasts of glacier recession patterns, summer temperatures and precipitation showed the average glacier area in western China might be reduced by 27.2 percent by 2050, said the report.

Ocean glaciers, affected by wet airflow from the oceans, would shrink by 52.5 percent, and Asian continental glaciers, formed in the continental climate would shrink by 24.4 percent.

Glaciers are part of the landscape in west China’s high mountainous regions in the Qinghai-Tibetan Plateau, the Pamir Plateau and the Himalayas.

The report warned that global warming would reduce the seasonal snowfall period while melting area would be higher, contributing to the sharp decline.

Ice volumes would decrease substantially and the runoff water to rivers would fall sharply.

Moreover, climate change would not relieve water shortages in northwest China, but reduce river runoff by 20 to 40 percent in Ningxia Hui Autonomous Region, Gansu and Qinghai provinces and Xinjiang Uygur Autonomous Region.

According to the report, extreme drought affects 697,000 square kilometers of China and drought affects 2.98 million square kilometers, adding up to 38.3 percent of the country’s land area. A 4-degree Celsius rise in temperatures would increase the drought-affected area by 843,000 square kilometers.

Glacier shrinkage would also threaten China’s agriculture sector.

The report warned that overall crop production capacity would drop by 5 percent to 10 percent by 2030 due to global warming, especially in wheat, rice and corn, and the impact would worsen after 2050.

The Chinese government had attached importance to tackling the problems caused by climate change and taken effective measures to reduce the negative impacts, said Sun Cuihua, an official with the National Development and Reform Commission (NDRC), Friday at the climate talks.

At the end of last year, the government announced plans to cut greenhouse gas emissions per unit of GDP by 40 to 45 percent by 2020 from 2005 levels.

As part of that goal, the government had stepped up closures of outdated production capacity, which had been blamed for pollution and hindering the upgrading of industry.

After three rounds of talks this year, which are moving slowly towards a negotiating text for the Cancun meeting in Mexico at the end of the year, more than 3,000 delegates from 194 nations gathered in Tianjin from Oct. 4 to 9 to accelerate the search for common ground.

However, the gap remains wide between the developed and developing nations as the former remain wary of green technology transfers and additional financing to poorer nations.

Montana’s melting glaciers: The poster-child for climate change

2010.10.07 – Original Source: CNN

As recently as 100 years ago, Montana’s Glacier National Park had more than 150 glaciers throughout its more than one million acres.

In 2005 only 27 remained. Today the total is down to a just 25 and those that are left are mere remnants of their former frozen selves.

With warmer temperatures and changes to the water cycle, scientists predict Glacier National Park will be glacier-free by 2030.

Daniel Fagre, a U.S. Geological Survey (USGS) ecologist who works at the national park believes that even those estimates are too conservative and says the park’s namesakes will be gone about ten years ahead of their predicted demise.

“The glaciers have been around for the last seven thousand years,” he told CNN, “and if we are going to lose them in the next 10 or 20 years that is a pretty radical shift.”

The rapid melting of glaciers has led scientists to believe that mountains are more susceptible to global warming than the lowlands beneath them.

“Mountain ecosystems have been changing about twice as fast as the rest of the globe. We have had temperature increases that are two times greater than the average,” said Fagre.

Many scientists are now concerned about the cascading effects on the landscape and the consequences for all species — including humans.

“Many people are directly dependent on the water coming out of mountains and in the arid western United States that figure is much larger, it is about 85 percent,” said Fagre.

“So even if you live a long ways a way you are tied to the water in mountains and so we have a lot of concerns of future climate change scenarios.”

Fagre says mountains are the “water towers of the world” with 70 percent of the world’s fresh water frozen in glaciers.

CNN traveled to the edge of Grinnell glacier that is at an altitude averaging 7,000 feet (2,100 meters) and was named after George Bird Grinnell, an early American conservationist and explorer.

“When George Grinnell came here in 1887 he described this place as being a thousand foot high in ice and this entire basin was filled to the mountaintop,” said Fagre. “Now I stand beside a lake that is 65 meters or 187 feet deep.”

We could see chunks of ice falling off, and others just dripping away. Fagre bent down to show us what’s underneath the thin edge of the glacier.

“Look under here and you can see there is a lot of mucky sauce stuff and this is a lot of the rock flour ground by the glacier because it has been dragging rocks across the underlying rock layer and rubbing those two together creating this very fine material,” he said.

“Many people would not be impressed by this little dirty glacier that seems to be obviously falling apart, that has become very tiny and decrepit — and people often think about glaciers as these beautiful white expansive, blue colors – but those are healthy glaciers and this one is not. This one is on its last legs.”

In 1997, USGS Physical Scientist Lisa McKeon and Fagre started the Repeat Photography Project at Glacier National Park tracking down old photographs of the park’s glaciers taken by first explorers in the 1900s and comparing them with their own images. View the historical images here

McKeon and other USGS scientists try to re-photograph the exact spot where the historic photograph was taken, though it’s not always possible when the original photographer was standing on ice that is now long gone.

“If you look at these pictures, you cannot say they haven’t changed over time. It’s very obvious,” says McKeon.

Glacier National Park is celebrating its 100th anniversary this year but soon the glaciers that gave the park its name will be gone.

“Glacier National Park has been the poster child park for climate change for a lot of people in the country and I think that there has been pretty sensational news about the glaciers disappearing in fairly short order,” says Chas Cartwright, Glacier National Park Superintendent.

“There is a lot less water coming off the mountain. There are dramatic changes in vegetation. It begs the question: how is that going to impact wildlife in this park?”

Many of the plant and animal species that call the park home require cold water, meaning the ecosystem of the park may change dramatically when the glaciers are gone.

There is a general consensus that man is contributing to the planet’s changing climate. Some skeptics remain, but Dan Fagre isn’t one of them.

“I think on a global scale when you look at all the ice disappearing all around the world, there is no other explanation for that then climate change that is driven by people,” he said.

What is beyond doubt is that whatever the causes magnificent and environmentally crucial glaciers around the world are retreating: a loss to nature and to the human species.

Himalayas Unsettled by Melting Glaciers, More Avalanches

2010.10.04 – Original Source: IPS

For the last two climbing seasons, Dawa Sherpa has missed scaling the summit of Mt Everest. But the climate ambassador for the World Wildlife Fund (WWF) and two-time Everest summiteer may not be relishing the thought of bearing witness once more to the impact of rising temperatures on the world’s highest peak.

The Tso Rolpa glacial lake in central Nepal has grown due to the faster melting of snow with global warming. Credit:Kishor Rimal/IPS

Indeed, he says that even making one’s way just up to Base Camp, which lies at an altitude of 5,380 metres, can already give one the dismal view of the devastation climate change is wreaking.

“Snow cover in the mountains is decreasing, crevasses are opening up in the glaciers,” says Dawa. “Avalanches (have been) occurring frequently (in) the past two years.”

In 2010, one of his Sherpa staff lost his life to an avalanche. Dawa also recalls Appa Sherpa, the 20-time Everest summiteer who has been climbing Everest since 1990, as saying last year that he has seen small puddles of water even at an altitude of 8,000 metres.

Snow and glaciers cover about 10 percent of the area of Nepal, where about 10 percent of the stream flows can be traced back to the glaciers.

Melting glaciers and receding snowlines, however, are just among the many manifestations of climate change in this tiny Himalayan nation.

Ministry of Forests and Soil Conservation Joint Secretary Dr Jagadish Chandra Baral shares with IPS a striking example of how climate change has been affecting Nepal’s horticulture sector.

“The apple-growing belt in the Mustang district is gradually shifting to higher altitudes,” says Baral, who writes frequently on climate change, because warming temperatures have resulted in their fruits getting worms. “People there claim that while they could easily produce healthy apples as low as Lete (2,480 metres) until a few years ago, the apples now tend to catch worms even in higher altitudes like Larjung (2,550 metres), Kobang (2,640 metres) and Marpha (2,670 metres).”

Mustang is located near the Tibet border. Recently, a village there was dubbed as Nepal’s first ‘climate refugee village’.

Efforts are now underway to resettle the entire village of Dhe to a lower area of Mustang. Among other things, the sources of water there are drying up, while the flora in and around the area have been vanishing fast, leaving the villagers’ cattle herds and other grazing animals with little to eat.

According to the English-language national daily ‘Republica’, which broke the news about Dhe in June, “(a) total of 150 people (23 households) …are being shifted due to the adverse impact of climate change on the livelihoods of the poor in the village”.

“Dhe village has been facing an acute shortage of water for irrigation over the last six to seven years,” it added. “The irrigated land over the period has also been reduced to less than 50 percent and animal husbandry (particularly goat keeping) has declined by 40 to 45 percent.

The irony is that Nepal itself is said to contribute next to nothing to climate change, which is traced by experts to greenhouse gas emissions of countries around the world.

China and India, which sandwich Nepal, in fact happen to be two of the world’s fastest industrialising and highest carbon dioxide-emitting countries.

Earlier in 2010, though, those who have expressed doubt that climate change is real had a field day when the United Nation’s Intergovernmental Panel on Climate Change (IPCC) announced it had made a mistake in saying the Himalayan glaciers may be gone by 2035. The climate-change sceptics took this as yet another piece of evidence that much of what had been said of the global phenomenon had been nothing but hysterical hype.

But IPCC has clarified that while it had made an error on the date, it did not make a mistake about the melting away of the Himalayan glaciers.

Madan Shrestha of the Nepal Academy of Science and Technology also remarks, “We have ample scientific evidence to prove that climate change is causing the Himalayan glaciers to retreat.”

Shrestha has been studying Nepal’s glaciers since 1974, when he was a part of the Glaciological Expedition to Nepal (a joint effort of Japan and Nepal).

He says that he was shocked beyond belief to see a picture taken in October 2009 of the Yala glacier (5,100 metres to 5,700 metres) in Lamtang area in central Nepal. Comments Shrestha: “The photograph was evidence of the fact that the glacier’s mass had decreased and there was a significant terminus retreat.”

A comparative analysis of photographs taken during different time periods clearly reveals that the fate of other glaciers such as AX010 (4,950 metres to 5,390 metres) glacier in Shorong mountain in East Nepal is no different, he adds.

Shrestha says, though, that since Nepal’s contribution to global climate change is minimal, there is not much it needs to do in terms of mitigation. “As a token response to international efforts we should voice our willingness to be a part of mitigation efforts,” he says, “but our focus has to be on adaptation”.

By that, he means introducing heat-resistant crop varieties and working to strengthen the dam structures so that they can withstand increased water pressure, among other thing. He says that Nepal can take a cue from Bangladesh, which has already introduced a flood-resistant variety of rice.

“It is high time we factored in climate change in our development discourse,” says Shrestha. “This has simply been not happening.”

Is global ice mass increasing or decreasing?

Original Source: Skeptical Science – “Ice isn’t melting”

The skeptic argument…

Thanks to a rapid rebound in recent months, global sea ice levels now equal those seen 29 years ago, when the year 1979 also drew to a close. In fact, the rate of increase from September onward is the fastest rate of change on record, either upwards or downwards. The data is being reported by the University of Illinois’s Arctic Climate Research Center, and is derived from satellite observations of the Northern and Southern hemisphere polar regions (Daily Tech).

What the science says…

Ice mass loss is occuring at an accelerated rate in Greenland, Antarctica and globally from inland glaciers. Arctic sea ice is also falling at an accelerated rate. The exception to this ice loss is Antarctic sea ice which has been growing despite the warming Southern Ocean. This is due to local factors unique to the area.

Figure 1 shows gravity satellite measurements of Greenland ice mass from April 2002 to February 2009 (Velicogna 2009). The blue line/crosses show monthly values of ice mass. The red crosses have seasonal variability removed. The green line is the best fitting quadratic trend. The best fitting trend finds that Greenland ice loss is accelerating at a rate of 30 Gigatonnes/yr2. Greenland’s mass loss doubled over the 9 year period. More on Greenland…

Figure 1: Time series of ice mass changes for the Greenland ice sheet estimated from GRACE monthly mass solutions for the period from April 2002 to February 2009. Unfiltered data are blue crosses. Data filtered for the seasonal dependence using a 13-month window are shown as red crosses. The best-fitting quadratic trend is shown (green line). (Velicogna 2009)

Figure 2 shows gravity measurements of land ice mass changes in Antarctica for the period April 2002 to February 2009 (Velicogna 2009) . The blue line/crosses show the unfiltered, monthly values. The red crosses have seasonal variability removed. The green line is the best fitting trend. Ice loss is accelerating at a rate of 26 Gigatonnes/yr2. The Antarctic ice sheet plays an important role in the total contribution to sea level. That contribution is continuously and rapidly growing.

Figure 2: Ice mass changes for the Antarctic ice sheet from April 2002 to February 2009. Unfiltered data are blue crosses. Data filtered for the seasonal dependence are red crosses. The best-fitting quadratic trend is shown as the green line (Velicogna 2009).

Globally, glaciers are shrinking in area and thickness and the melt rate has accelerated dramatically since the mid-1990s. The National Snow and Ice Data Center have calculated global change in glacier volume – their results show glaciers are shrinking at an alarming rate. More on glaciers…

Figure 3: Annual change in global glacier thickness (left axis, meters of water equivalent, m/yr) and cumulative value (right axis, m), based on surface area-weighted mass balance observations. Dates of major volcanic eruptions are shown, since stratospheric aerosols have a cooling effect on climate. Red arrow highlights volume rate change (source: NSIDC) .

Global warming has a clearly observed, long term effect on Arctic sea ice. In fact, although climate models predict that Arctic sea ice will decline in response to greenhouse gas increases, the current pace of retreat at the end of the melt season is exceeding the models’ forecasts by around a factor of 3 (Stroeve 2007). More on Arctic ice…

Figure 4: September Arctic Sea Ice Extent (thin, light blue) with long term trend (thick, dark blue). Sea ice extent is defined as the surface area enclosed by the sea ice edge (where sea ice concentration falls below 15%).

The one exception to this pattern of accelerating ice loss is Antarctic sea ice which has shown long term growth since satellites began measurements in 1979. This is despite the fact that the Southern Ocean has been warming faster than the rest of the world’s oceans. Globally from 1955 to 1995, ocean have been warming at 0.1°C per decade. In contrast, the Southern Ocean has been warming at 0.17°C per decade. Not only is the Southern Ocean warming, it is warming faster than the global trend.

If the Southern Ocean is warming, why is Antarctic sea ice increasing? There are several contributing factors. The hole in the ozone layer above the South Pole strengthens cyclonic winds that circle the Antarctic continent. The wind pushes sea ice around, creating areas of open water known as polynyas. More polynyas leads to increased sea ice production. Another contributor is changes in ocean circulation which cause less heat is transported upwards from the deeper, warmer layer. Hence less sea ice is melted.

Figure 5: Surface air temperature over the ice-covered areas of the Southern Ocean (top). Sea ice extent, observed by satellite (bottom). (Zhang 2007)

Photos show dramatic shrinking of Mount Everest glaciers

July 18, 2010 – Original Source: Telegraph, UK

Glaciers on Mount Everest are shrinking, according to startling new photographs.

The 1921 photograph taken by George Mallory of the Rongbuk Glacier and the northern slope of Mount Everest in the distance, Tibet Autonomous Region Photo: AFP/GETTY IMAGES

The two pictures show an “alarming” retreat in ice over more than 80 years.

The first was taken in 1921 by British mountaineer George Mallory, who later died trying to conquer Everest.

The Asia Society commissioned the same picture to be taken of the main Rongbuk glacier on the northern slope of Mount Everest in Tibet in 2007.

The new picture by mountaineer David Breashears show that the glacier is shrunk and withered.

A spokesman for the Asia Society said the picture was proof the ice is melting because of climate change, threatening water sources in highly populated areas of India and China.

“The photographs reveal a startling truth: the ice of the Himalaya is disappearing,” he said. “They reveal an alarming loss in ice mass.”

Mr Breashears retraced the steps of the 1921 British Mount Everest Reconnaissance Expedition Team, using photos taken then by surveyor and photographer Maj Edward Wheeler and amateur photographer George Mallory, who later died attempting to reach the Everest summit in 1924.

The series of photos, on display at an exhibition in New York, show how changes in temperature could be affecting the wider environment.

The issue of melting glaciers in the Himalaya is controversial following ‘glaciergate’. The United Nations science body the Intergovernmental Panel on Climate Change was forced to apologise after mistakenly claiming the Himalayan glaciers could all disappear by 2035.

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