Category Archives: Oceans

Melting ice cap triggering earthquakes in Greenland

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As a follow up to yesterday’s post regarding an ice-free Arctic, there is this regarding the land-bound ice of Greenland melting so fast that it is now starting to cause earthquakes.

The Guardian reports that the Melting ice cap triggering earthquakes:

The Greenland ice cap is melting so quickly that it is triggering earthquakes as pieces of ice several cubic kilometres in size break off.

Scientists monitoring events this summer say the acceleration could be catastrophic in terms of sea-level rise and make predictions this February by the Intergovernmental Panel on Climate Change far too low.

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He had flown over the Ilulissat glacier and “seen gigantic holes in it through which swirling masses of melt water were falling. I first looked at this glacier in the 1960s and there were no holes. These so-called moulins, 10 to 15 metres across, have opened up all over the place. There are hundreds of them.”

This melt water was pouring through to the bottom of the glacier creating a lake 500 metres deep which was causing the glacier “to float on land. These melt-water rivers are lubricating the glacier, like applying oil to a surface and causing it to slide into the sea. It is causing a massive acceleration which could be catastrophic.”

The glacier is now moving at 15km a year into the sea although in surges it moves even faster. He measured one surge at 5km in 90 minutes – an extraordinary event.

Veli Kallio, a Finnish scientist, said the quakes were triggered because ice had broken away after being fused to the rock for hundreds of years. The quakes were not vast – on a magnitude of 1 to 3 – but had never happened before in north-west Greenland and showed potential for the entire ice sheet to collapse.

Dr Corell said: “These earthquakes are not dangerous in themselves but the fact that they are happening shows that events are happening far faster than we ever anticipated.”

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An ice-free Arctic in just 23 years?

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Big fucking surprise. Or not. Look… how many times do we have to see these words over and over? “Sooner than expected”, “much worse than previously thought”. I’ve said it before, this is happening at a pace far faster than even the worst predictions. We have got to start thinking of climate change as RIGHT FUCKING NOW. This is NOW. This is not 100 years from now. This is not great grand children or the next generation. FUCK. Stop eating meat. Stop driving. Stop consuming. FUCKING STOP.

I hate humanity and truthfully, I think I’m starting to take pleasure in seeing people suffer from weather related catastrophes. If only that suffering were more focused on the U.S. and other primary contributors of atmospheric carbon. It’s harsh I know but FUCK. How stupid, shortsighted and selfish can we be?

seaice1979-2007sep05.jpg
Comparison of sea ice area on September 5, 1979 and September 5, 2007.

Sea ice area in early September has declined 42% in the 28 years since 1979.
Image credit: University of Illinois Polar Research Group.

Jeff Masters over at Wunderground discusses the issue:

None of our computer climate models predicted that such a huge loss in Arctic ice would occur so soon. Up until this year, the prevailing view among climate scientists was that an ice-free Arctic ocean would occur in the 2070-2100 time frame. The official word on climate change, the February 2007 report from the U.N.-sponsored Intergovernmental Panel on Climate Change (IPCC), warned that without drastic changes in greenhouse gas emissions, Arctic sea ice will “almost entirely” disappear by the end of the century. This projection is now being radically revised. Earlier this year, I blogged about a new study that predicted abrupt losses of Arctic sea ice were possible as early as 2015, and that we could see an ice-free Arctic Ocean as early as 2040. Well, the Arctic Ocean has suffered one of the abrupt losses this study warned about–eight years earlier than this most radical study suggested. It is highly probable that a complete loss of summer Arctic sea ice will occur far earlier than any scientist or computer model predicted. In an interview published yesterday in The Guardian Dr. Mark Serreze, and Arctic ice expert with the National Snow and Ice Data Center, said: “If you asked me a couple of years ago when the Arctic could lose all of its ice, then I would have said 2100, or 2070 maybe. But now I think that 2030 is a reasonable estimate. It seems that the Arctic is going to be a very different place within our lifetimes, and certainly within our children’s lifetimes.” While natural fluctuations in wind and ocean circulation are partly to blame for this loss of sea ice, human-caused global warming is primarily to blame. In the words of Dr. Serreze: “The rules are starting to change and what’s changing the rules is the input of greenhouse gases. This year puts the exclamation mark on a series of record lows that tell us something is happening.”

The implications
The melting of the Arctic sea ice will not raise ocean levels appreciably, since the ice is made up of frozen sea water that is floating in the ocean. Sea ice melt does contribute slightly to sea level rise, since the fresh melt water is less dense than the salty ocean water it displaces. According to Robert Grumbine’s sea level FAQ, if all the world’s sea ice melted, it would contribute to about 4 millimeters of global sea level rise. This is a tiny figure compared to the 20 feet of sea level rise locked up in the ice of the Greenland ice sheet, which is on land.

The biggest concern about Arctic sea ice loss is the warmer average temperatures it will bring to the Arctic in coming years. Instead of white, reflective ice, we will now have dark, sunlight-absorbing water at the pole, leading to a large increase in average temperature. Warmer temperatures will accelerate the melting of the Greenland ice sheet, which holds enough water to raise sea level 20 feet. The official word on climate, the 2007 IPCC report, predicted only a 0.6-1.9 foot sea level rise by 2100, due to melting of the Greenland ice sheet and other factors. I believe these estimates will need to be revised sharply upwards in light of the unexpectedly high Arctic sea ice loss this summer.

One more point–global warming skeptics often criticize using computer model climate predictions as a basis for policy decisions. These models are too uncertain, they say. Well, the uncertainty goes both way–sometimes the models will underestimate climate change. We should have learned this lesson when the ozone hole opened up–another case where the models failed to predict a major climate change. The atmosphere is not the well-behaved, predictable entity the models try to approximate it as. The atmosphere is wild, chaotic, incredibly complex, and prone to sudden unexpected shifts. By pumping large amounts of greenhouse gases into the air, we have destabilized the climate and pushed the atmosphere into a new state it has never been in before. We can expect many more surprises that the models will not predict. Some of these may be pleasant surprises, but I am expecting mostly nasty surprises.

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Climate Change Round-up

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I suppose it is a good sign that I’m having a hard time keeping up with all of the recent media coverage of climate change. I would like to point out though that while the coverage is now consistent via the web I’m not seeing it nearly as much on the television. I don’t watch much but when I do flip on the TV and CNN I’m much more likely to see discussion of stupid, irrelevant celebrity gossip than I am discussion of climate change. That’s just plain fucked up. Until the corporate media stop the daily bullshit coverage of Anna Nicole’s baby’s daddy and replace it with daily discussion of peak oil, climate change, and sustainable development they are as much a part of the problem as they have always been.

Summary of the latest installment of the Intergovernmental Panel on Climate Change (IPCC) report: Climate Change 2007: Climate Change Impacts, Adaptation and Vulnerability [PDF – 547KB]

Billions face climate change risk:

Billions face climate change risk

The impact of climate change has been a major source of dispute
Billions of people face shortages of food and water and increased risk of flooding, experts at a major climate change conference have warned.

Damage already done for some natural wonders

BRUSSELS, Belgium (AP) — While governments grapple with the politics of global warming, some of the world’s greatest treasures already are being damaged and threatened with destruction.

Conservationists have drawn up priorities for action to salvage some of nature’s wonders that are feeling the heat of climate change — from the Himalayan glaciers to the Amazon rain forests and the unique ecosystem of the Mexican desert.

Many of the regions at risk were singled out in a report by the Intergovernmental Panel on Climate Change, an authoritative body of 2,500 scientists. The report is undergoing governmental review at a five-day conference in Brussels.

On Thursday, diplomats and scientists were negotiating the text of a 21-page summary of the full 1,572-page scientific report. It projects specific consequences for each degree of rising global temperatures, which the IPCC agrees is largely caused by human activity.

On the sidelines of the conference, the World Wildlife Fund for Nature issued a list of 10 regions suffering irreversible damage from climate change. The group also listed where it has projects to limit further damage or help people adapt to new conditions.

“What we are talking about are the faces of the impacts of climate change,” said Lara Hansen, WWF’s chief scientist on climate issues.

The WWF is among the largest of many nongovernment organizations to take up the challenge of climate change.

The Nature Conservancy, based in Arlington, Virginia, is another. It has projects to protect coral reefs off Florida, in the coral triangle of Indonesia and in Papua New Guinea. It also is trying to preserve native alpine meadows in China and conserve vegetation in California’s Sierra Nevada mountains.

Though climate change has been discussed for decades, Hansen said the effects were now becoming visible. “It’s only in the past decade that we can go outside and see for ourselves what’s happening,” she told The Associated Press.

Some damage is reversible, Hansen said. Although melted glaciers cannot be restored, some coral reefs can recover.

But as natural landmarks deteriorate, she said more attention will have to be paid to adapting to change, not only trying to prevent it, and not enough experts are being trained to help people acclimatize.

“There’s a massive void ahead of us in getting new people,” she said.

U.N.: Warming ruining society, nature:

Top climate experts warned on Friday that global warming will cause faster and wider damage than previously forecast, ranging from hunger in Africa and Asia to extinctions and rising ocean levels.

Study: Climate change could bring new U.S. Dust Bowl

Changing climate will mean increasing drought in the southwestern United States, where water already is in short 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. 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 reduction in rainfall could reach levels of the 1930s Dust Bowl that ranged throughout the Midwestern United States, Seager said in a telephone interview.

Arctic lost part of its perennial sea ice in 2005: NASA

Global warming may already be having an effect on the Arctic which in 2005 only replaced a little of the thick sea ice it loses and usually replenishes annually, a NASA study said Tuesday.

Scientists from the US space agency used satellite images to analyze six annual cycles of Arctic sea ice from 2000 to 2006.

Sea ice is essential to maintaining and stabilizing the Arctic’s ice cover during its warmer summer months.

But “recent studies indicate Arctic perennial ice is declining seven to 10 percent each decade,” said Ron Kwok from NASA’s Jet Propulsion Laboratory in Pasadena, California.

“Our study gives the first reliable estimates of how perennial ice replenishment varies each year at the end of the summer.

“The amount of first-year ice that survives the summer directly influences how thick the ice cover will be at the start of the next melt season.”

The team observed that only 4.0 percent, about 2.5 million square kilometers (965,000 square miles) of thin ice survived the 2005 summer melt to replenish the perennial cover.

It was the weakest ice cover since 2000, and so there was 14 percent less permanent ice cover in January 2006 than in the corresponding period the year before.

“The winters and summers before fall 2005 were unusually warm,” Kwok said. “The low replenishment seen in 2005 is potentially a cumulative effect of these trends.

“If the correlations between replenishment area and numbers of freezing and melting temperature days hold long-term, it is expected the perennial ice coverage will continue to decline.”

Records dating back to 1958 have shown a gradual warming of Arctic temperatures which speeded up in the 1980s.

“Our study suggests that on average the area of seasonal ice that survives the summer may no longer be large enough to sustain a stable, perennial ice cover, especially in the face of accelerating climate warming and Arctic sea ice thinning,” Kwok added.

Scientists say Antarctic ice sheet is thinning

A Texas-sized piece of the Antarctic ice sheet is thinning, possibly due to global warming, and could cause the world’s oceans to rise significantly, polar ice experts said on Wednesday.

They said “surprisingly rapid changes” were occurring in Antarctica’s Amundsen Sea Embayment, which faces the southern Pacific Ocean, but that more study was needed to know how fast it was melting and how much it could cause the sea level to rise.

The warning came in a joint statement issued at the end of a conference of U.S. and European polar ice experts at the University of Texas in Austin.

The scientists blamed the melting ice on changing winds around Antarctica that they said were causing warmer waters to flow beneath ice shelves.

The wind change, they said, appeared to be the result of several factors, including global warming, ozone depletion in the atmosphere and natural variability.

The thinning in the two-mile-(3.2-km)- thick ice shelf is being observed mostly from satellites, but it is not known how much ice has been lost because data is difficult to obtain on the remote ice shelves, they said.

Study is focusing on the Amundsen Sea Embayment because it has been melting quickly and holds enough water to raise world sea levels six meters, or close to 20 feet, the scientists said.

Antarctic Glaciers’ Sloughing Of Ice Has Scientists at a Loss

Some of the largest glaciers in Antarctica and Greenland are moving in unusual ways and are losing increased amounts of ice to the sea, researchers said yesterday.

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Complicating the situation for those studying Antarctica, some parts of the continent are gaining ice depth through snowfall while temperatures on the tip of the Antarctic peninsula, the continent’s closest point to South America, are rising faster than almost anywhere else on the planet. The surprisingly fast-moving glaciers are largely on the West Antarctic ice sheet.

Wingham, of University College London, and Andrew Shepherd of the University of Edinburgh said satellite radar readings show that overall, each year the ice loss from Greenland and Antarctica amounts to about 10 percent of the rise in the global sea level, which totals about one-tenth of an inch per year. The net loss of Antarctic ice is estimated to be 25 billion metric tons a year, despite the growth of the ice sheet in East Antarctica.

Because such a large percentage of the world’s ice is found in those two locations, scientists are carefully watching for signs of increased ice loss. If that process accelerates, researchers say, it could result in a substantial, and highly disruptive, increase in sea levels worldwide.

In Greenland, glaciers appear to be moving more quickly to sea because melting ice has allowed the sheet to slide more easily over the rock and dirt below. In Antarctica, the loss is believed to be associated with the breaking off into seawater of ice deep under the ice sheet with little-understood internal dynamics that put increased pressure on the massive ice streams.

Southern Ocean current faces slowdown threat

The impact of global warming on the vast Southern Ocean around Antarctica is starting to pose a threat to ocean currents that distribute heat around the world, Australian scientists say, citing new deep-water data.

Melting ice-sheets and glaciers in Antarctica are releasing fresh water, interfering with the formation of dense “bottom water,” which sinks 4-5 kilometers to the ocean floor and helps drive the world’s ocean circulation system.

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Oceans Warming and Rising

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From the Inter Press Service, Oceans Warming and Rising:

Ocean levels will rise faster than expected if greenhouse gas emissions continue to rise, a leading German researcher warns.

Using data from the U.S. National Aeronautics and Space Administration (NASA), Stefan Rahmstorf, professor of physics of the oceans at the University of Potsdam near Berlin estimates that sea level could rise 140 cm by 2100.

Rahmstorf, member of the German Advisory Council on Global Change, is considered a leading European researcher on global warming and its effect on oceans.

“The semi-empirical model we used to process NASA data showed a proportional constant sea level rise of 3.4 mm per year per degree Celsius,” Rahmstorf told IPS. “Then we applied this constant proportionality to future earth surface warming scenarios of the Intergovernmental Panel on Climate Change (IPPC), and came to estimate that by the year 2100, sea level could rise between 50 and 140 cm above the level measured in 1990.”

Through the 20th century, global warming led to an average 20cm rise in sea level. But most computer models of climate change used at present significantly underestimate sea level rise, Rahmstorf said. “Future projections of sea level based on these climate models are therefore unreliable.”

Currently, sea level is rising at three cm per decade, faster than projected in the scenarios of the IPCC Third Assessment Report, Rahmstorf added.

The IPCC, an intergovernmental team of scientists carrying out a wide range of research related to climate change, was established in 1988 by the World Meteorological Organisation and the United Nations Environmental Programme. The IPCC aims to assess scientific, technical and socio-economic information relevant for understanding of climate change, its potential impact, and options for adaptation and mitigation.

Scientific research has found that industrial activities have produced greenhouse gas emissions considerably higher than levels observed before the industrial revolution.

Concentration of carbon dioxide (CO2), the most potent of greenhouse gases, has risen from about 280 parts per million (ppm) in the atmosphere in the year 1750 to about 380 ppm today.

This rise is primarily due to the burning of fossil fuels, and to a lesser extent, deforestation. Scientists estimate that if the present emissions trend continues, the atmosphere could heat up by about five 5 degrees Celsius by 2100.

Studies by the Potsdam Institute for Climate Impact Research suggest that this would roughly be the temperature difference between an ice age and a warm stage. But while the rise of average temperatures by some five degrees between the last great ice age and today took 5,000 years, the new global warming would need only 100 years.

Rahmstorf acknowledged that forecasts of global warming and its effects on sea levels continue to be marked by uncertainty. “The fact that we get such different estimates using different methods shows how uncertain our sea level forecasts still are,” Rahmstorf told IPS.

A major reason for the uncertainty is the behaviour of the large ice sheets in Greenland and Antarctica.

A likely consequence of a massive melting of the ice masses on the North Pole could be the breakdown of the North Atlantic Current (NAC). The NAC is the northern extension of the Gulf Stream, and constitutes a warm water current flowing between Britain and Iceland. This has considerable impact in moderating the North European and Scandinavian climate.

“One critical factor for the continuation of this current is the amount of fresh water that enters the Northern Atlantic region in the future,” Rahmstorf said. “This will depend in large part on the speed at which Greenland’s ice sheet melts.”

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Climate change and phytoplankton

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One of those many details regarding the effects of climate change: phytoplankton. I continue to be amazed in my conversations with the people around me and how little they know about climate change and what it all really means. Most folks that I encounter seem to have no clue about how it is our earth actually works or the delicate balance that keeps it all going.

Climate Change is Killing the Oceans’ Microscopic ‘Lungs’

Global warming has begun to change the way microscopic plant life in the oceans absorbs carbon dioxide from the atmosphere – a trend that could lead to a dramatic increase in the heating power of the greenhouse effect.

Satellite data gathered over the past 10 years has shown for the first time that the growth of marine phytoplankton – the basis of the entire ocean food chain – is being adversely affected by rising sea temperatures.

Scientists have found that as the oceans become warmer, they are less able to support the phytoplankton that have been an important influence on moderating climate change.

The fear is that as sea temperatures continue to rise as a result of global warming, the loss of phytoplankton will lead to a positive-feedback cycle, where increases in carbon dioxide concentrations in the atmosphere leads to warmer oceans, and warmer oceans lead to increasing carbon dioxide concentrations.

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“Rising levels of carbon dioxide in the atmosphere are a key part of global warming. This study shows that as the climate warms, phytoplankton production goes down, but this also means that carbon dioxide uptake by the ocean plants will decrease,” Professor Behrenfeld said. “That would allow carbon dioxide to accumulate more rapidly in the atmosphere, making the problem worse.”

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Despite their small size, phytoplankton account for about half of the photosynthesis carried out by all plants on Earth. And phytoplankton have a high turnover because they are quickly eaten by small marine animals – making them even more vulnerable to climate change.

“This fast turnover and the fact that phytoplankton are limited to a thin veneer of the ocean surface, where there is enough sunlight to sustain photosynthesis, makes them very responsive to climate change,” Professor Behrenfeld said. “This was why we could relate productivity changes to climate variability in only a 10-year record. Such connections would be much harder to detect from space for terrestrial plant biomass.”

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