Block’s Indicator of Sustainable Growth

by Ray Block

The irony is that in rich countries, it is the affluent who live at or close to the coast, while in the developing countries, a large proportion of the poor live close to the coast.

While climate change sceptics still abound, there are few dissenters from the evidence that sea levels are rising.  Yet it is climate change which is the dominant cause of rising sea levels. You only need to ask the affluent, whose houses and apartments hug the east and west coasts of United States, and nervously watch the relentless march of tidal waves and beach erosion.

Predictions at the European Geosciences Union conference in Vienna held on April 16 2008 were stark that the pace of rising sea levels is accelerating faster than previously believed. Back in early 2001, the Intergovernmental Panel on Climate Change (IPCC) had projected that during the 21st Century, sea levels would rise by 0.09-0.88 meters (4 to35 inches) as a result of thermal expansion and ice melting.

This seemed very probable at the time, given the slow rate of rising sea levels in past centuries. Indeed, sea levels had been very stable for 2000 years, rising only 2 cm in the 18th century, 6cm in the 19th century, and then rising by a larger 19cm in the 20th century due to melting ice sheets. But sea levels have already been increasing again this century, and the rise will probably accelerate even further as the century goes on.

Already by 2002, two scientists from the University of Colorado’s Institute of Arctic and Alpine Research showed that the melting of large glaciers on the west coast of Alaska and Northern Canada had increased again. This study was reinforced by the US Geological Survey indicating that glaciers were shrinking in all 11 of Alaska’s glaciated mountain ranges.

The fourth landmark report of the IPCC in 2007 suggested that rising sea levels by the end of this century were “most likely” to be between 18 and 59 cm.

But this estimate was immediately criticised by a number of climate scientists as understating the likely outcome. Dr James Hansen, director of NASA Goddard Institute for Space Studies, the outspoken global warming advocate said that the extent of seas rising was under estimated by what would happen in the event of  future disintegration of ice sheets in parts of Greenland and West Antarctica.

The caution went out of the door at the European Geosciences Union conference in Britain held in April 2008, with forecasts of rising in sea levels three times greater than predicted by the IPCC in 2007. Svetlana Jevrejeva of the Proudman Oceanographic Laboratory told the conference that the estimate was based on a new model allowing accurate reconstruction of sea levels over the past 2000 years.

The pace at which sea levels are rising is accelerating even faster, the Proudman  scientists reported that their new model showed sea levels rising by 0.8 -1.5 meters (2.5ft-4ft11 in) by next century.

Simon Holgate of Proudman told the conference that the “IPCC numbers are underestimates.” Echoing James Hansen, he said that the IPCC had not accounted for ice dynamics- the more rapid movement of ice sheets due to melt water, which could markedly speed up their disappearance and boost sea levels.

The ice dynamics effect is said to generate around one-third of the future rise in sea levels, says another researcher, Steve Nerem of the University of Colorado. Said Nerem: “there is a lot of evidence out there that we will see around one meter in 2100.” He added that the sea rise would not be uniform around the globe and that more research was needed to determine the effects on single regions.

James Hansen told the television program Living on Earth in February 2007, “we have very limited time to get on a different path with our energy use and greenhouse gas emissions, or we’re going to end up with unstoppable problems in the future.”

In addition to rising sea levels, scientists are also alarmed by the increase in acidity in the oceans. The oceans absorb a third of total carbon dioxide emissions world wide. But the intake, caused largely by fossil fuel burning, is turning this vast carbon sink acidic. Because of the increased acidity, less carbonate ions are available, which means the calcification rates of the organisms are decreasing and their shells and skeletons thinning.

Most calcifying organisms such as corals, mussels, algae and plankton investigated so far, respond negatively to the more acidic ocean waters.

The chair person of the EuroClimate program Scientific Committee, Jelie Bijma said in May 2008 that “ocean acidification is more rapid than ever in the history of the earth”

The first global study to identify populations at greatest risk from rising sea levels and more intense cyclones linked to climate change was published in April 2007 by the peer reviewed journal Environment and Urbanization. The research showed that 634 million people – one tenth of the global population – live in coastal areas that lie within 10 metres above sea level.

21 per cent of the urban populations of least developed nations are in the 0 to 10 metre zone. About 75 per cent of people in the zone are in Asia.  21 nations have more than half of their population in the danger zone.

Asia is the worst affected area in terms of flood disasters. Between 1994 and 2004, about one third of the 1,562 flood disasters, half of the 120,000 people killed and 98 per cent of the two million people affected by these disasters were in Asia.

The irony is that in rich countries, it is the affluent who live at or close to the coast, while in the developing countries, a large proportion of the poor live close to the coast.

While climate change sceptics still abound, there are few dissenters from the evidence that sea levels are rising.  Yet it is climate change which is the dominant cause of rising sea levels. You only need to ask the affluent, whose houses and apartments hug the east and west coasts of United States, and nervously watch the relentless march of tidal waves and beach erosion.

Predictions at the European Geosciences Union conference in Vienna held on April 16 2008 were stark that the pace of rising sea levels is accelerating faster than previously believed. Back in early 2001, the Intergovernmental Panel on Climate Change (IPCC) had projected that during the 21st Century, sea levels would rise by 0.09-0.88 meters (4 to35 inches) as a result of thermal expansion and ice melting.

This seemed very probable at the time, given the slow rate of rising sea levels in past centuries. Indeed, sea levels had been very stable for 2000 years, rising only 2 cm in the 18th century, 6cm in the 19th century, and then rising by a larger 19cm in the 20th century due to melting ice sheets. But sea levels have already been increasing again this century, and the rise will probably accelerate even further as the century goes on.

Already by 2002, two scientists from the University of Colorado’s Institute of Arctic and Alpine Research showed that the melting of large glaciers on the west coast of Alaska and Northern Canada had increased again. This study was reinforced by the US Geological Survey indicating that glaciers were shrinking in all 11 of Alaska’s glaciated mountain ranges.

The fourth landmark report of the IPCC in 2007 suggested that rising sea levels by the end of this century were “most likely” to be between 18 and 59 cm.

But this estimate was immediately criticised by a number of climate scientists as understating the likely outcome. Dr James Hansen, director of NASA Goddard Institute for Space Studies, the outspoken global warming advocate said that the extent of seas rising was under estimated by what would happen in the event of  future disintegration of ice sheets in parts of Greenland and West Antarctica.

The caution went out of the door at the European Geosciences Union conference in Britain held in April 2008, with forecasts of rising in sea levels three times greater than predicted by the IPCC in 2007. Svetlana Jevrejeva of the Proudman Oceanographic Laboratory told the conference that the estimate was based on a new model allowing accurate reconstruction of sea levels over the past 2000 years.

The pace at which sea levels are rising is accelerating even faster, the Proudman  scientists reported that their new model showed sea levels rising by 0.8 -1.5 meters (2.5ft-4ft11 in) by next century.

Simon Holgate of Proudman told the conference that the “IPCC numbers are underestimates.” Echoing James Hansen, he said that the IPCC had not accounted for ice dynamics- the more rapid movement of ice sheets due to melt water, which could markedly speed up their disappearance and boost sea levels.

The ice dynamics effect is said to generate around one-third of the future rise in sea levels, says another researcher, Steve Nerem of the University of Colorado. Said Nerem: “there is a lot of evidence out there that we will see around one meter in 2100.” He added that the sea rise would not be uniform around the globe and that more research was needed to determine the effects on single regions.

James Hansen told the television program Living on Earth in February 2007, “we have very limited time to get on a different path with our energy use and greenhouse gas emissions, or we’re going to end up with unstoppable problems in the future.”

In addition to rising sea levels, scientists are also alarmed by the increase in acidity in the oceans. The oceans absorb a third of total carbon dioxide emissions world wide. But the intake, caused largely by fossil fuel burning, is turning this vast carbon sink acidic. Because of the increased acidity, less carbonate ions are available, which means the calcification rates of the organisms are decreasing and their shells and skeletons thinning.

Most calcifying organisms such as corals, mussels, algae and plankton investigated so far, respond negatively to the more acidic ocean waters.

The chair person of the EuroClimate program Scientific Committee, Jelie Bijma said in May 2008 that “ocean acidification is more rapid than ever in the history of the earth”

The first global study to identify populations at greatest risk from rising sea levels and more intense cyclones linked to climate change was published in April 2007 by the peer reviewed journal Environment and Urbanization. The research showed that 634 million people – one tenth of the global population – live in coastal areas that lie within 10 metres above sea level.

21 per cent of the urban populations of least developed nations are in the 0 to 10 metre zone. About 75 per cent of people in the zone are in Asia.  21 nations have more than half of their population in the danger zone.

Asia is the worst affected area in terms of flood disasters. Between 1994 and 2004, about one third of the 1,562 flood disasters, half of the 120,000 people killed and 98 per cent of the two million people affected by these disasters were in Asia.