Chilling global forecast
By Richard Macey
March 11, 2004
Global warming could disrupt the world's sea currents, sending Europe into a chill within 100 years and devastating tropical ocean life, a CSIRO scientist says.
Richard Matear, a Hobart-based marine researcher, said the oxygen content of deep ocean water between Australia and Antarctica had fallen 3 per cent since 1968.
If new research confirmed the decline was happening throughout the world's southern oceans, it would be a strong sign global warming was interfering with sea currents.
According to NASA "the thawing of sea ice covering the Arctic could disturb or even halt large currents in the Atlantic Ocean.
"Without the vast heat these currents deliver - comparable to the power generation of a million nuclear power plants - Europe's average temperature would likely drop 5 to 10 degrees."
While North America would not be as severely hit, the space agency said "such a dip in temperature would be similar to global average temperatures toward the end of the last ice age roughly 20,000 years ago".
While NASA said many scientists were sceptical, it quoted Dr Robert Gagosian, director of the private Woods Hole Oceanographic Institution, Massachusetts, as saying such a change in ocean currents could happen within 20 years.
Yesterday Dr Matear explained that if global warming continued melting Arctic ice and increasing evaporation, boosting rainfall in the North Atlantic, "the North Atlantic could be flooded with fresh water. The flood of fresh water reduces the density of the surface and prevents the water from sinking deep into ocean," he said, adding that the vertical sinking of sea water helped drive ocean circulation.
Officially called the thermo-haline circulation, the pattern is sometimes dubbed the Great Conveyer Belt.
Dr Matear said the decline in oxygen levels in deep water of the Southern Ocean was exactly what computer modelling suggested would be seen if global warming slowed this circulation, reducing the cold water flowing south of Australia. "Cold water is high in oxygen," he said.
Dr Matear said although it was too early to say what impact a shutdown of ocean currents would have on Australian temperatures, he agreed Europe could be sent into a severe chill.
"A decline of five degrees by end of this century . . . that wouldn't be unrealistic."
Dr Matear said a decline in oxygen levels would be particularly serious for sea life in the tropics, where the warmer water is already oxygen-poor.
World - OneWorld.net
Damage from Warming Becoming 'Irreversible,' Says New Report
Mon Mar 15, 9:50 AM ET
Jim Lobe, OneWorld US
WASHINGTON, D.C., Mar 15 (OneWorld) -- Ten years after the ratification of a United Nations (news - web sites) treaty on climate change, greenhouse gas emissions that lead to global warming are still on the rise, signaling a "collective failure" of the industrialized world, according to the Washington-based World Resources Institute (WRI), a leading environmental think-tank.
"We are quickly moving to the point where the damage will be irreversible," warned Dr. Jonathan Pershing, director of WRI's Climate, Energy and Pollution Program. "In fact, the latest scientific reports indicate that global warming is worsening. Unless we act now, the world will be locked into temperatures that would cause irreversible harm."
WRI researchers estimate that greenhouse gas emissions such as carbon dioxide rose 11 percent over the last decade, and will grow another 50 percent worldwide by 2020. Under the 1997 Kyoto Protocol (news - web sites), the international agreement that sets out specific targets to follow up on the treaty, 38 industrialized countries were supposed to reduce their emissions by an average of seven percent below 1990 levels by 2012.
The administration of former President Bill Clinton (news - web sites) signed the Kyoto Protocol, but President Bush (news - web sites) withdrew the U.S., which currently emits about 25 percent of the world's greenhouse gases, from negotiations over Kyoto's implementation.
Russia, which indicated initially that it intended to ratify the Protocol, remains undecided. As a result the Protocol--which must be ratified by countries whose greenhouse emissions totaled more than 55 percent of global emissions in 1990 in order to take effect--remains in limbo.
WRI decided to make a relatively rare public statement now, both because the tenth anniversary of the UNFCCC's ratification will take place next weekend and because of the growing pessimism surrounding the international community's ability and will to deal with the problem.
The UN Framework Convention on Climate Change (UNFCCC), which called for voluntary reductions in greenhouse emissions, was signed by, among others, then-President George H.W. Bush, at the Earth Summit in Rio de Janeiro in 1992 and took formal effect March 21, 1994. Today, 188 countries are signatories.
The Kyoto Protocol grew out of the UNFCCC when it became clear that plans for voluntary reductions would not meet the initial targets, and as climate and atmospheric scientists on the Intergovernmental Panel on Climate Change have become increasingly convinced that the rise in global temperatures of about one degree Fahrenheit over the last century is due primarily to artificial emissions, notably the combustion of fossil fuels, including coal, oil, and gas.
Studies over the past decade have shown that the warming trend continues. "The five warmest years in recorded weather history have taken place over the last six years," noted WRI's president, Jonathan Lash.
"The ten warmest years in recorded weather history have taken place since 1987. Whether it's the retreat of glaciers, the melting of the permafrost in Alaska, or the increase in severe weather events, the world is experiencing what the global warming models predict," he said.
Europe, the main champion of the Kyoto Protocol, suffered its hottest year on record last year. Some 15,000 people in France alone died due to heat stress in combination with pollution, while European agriculture suffered an estimated $12.5 billion in losses.
Britain's most influential scientist, Sir David King, recently excoriated the Bush administration for withdrawing from the Protocol and ignoring the threat posed by climate change. "In my view, climate change is the most severe problem we are facing today," he wrote in Science magazine, "more serious even than the threat of terrorism."
Even the Pentagon (news - web sites) recently issued a warning that global warming, if it takes place abruptly, could result in a catastrophic breakdown in international security. Based on growing evidence that climate shifts in the past have taken place with breathtaking speed, based on the freshening of sea water due to accelerated melting of glaciers and the polar ice caps.
Given enough freshening, the Gulf Stream that currently warms the North Atlantic would be shut off, triggering an abrupt decline in temperatures that would bring about a new "Ice Age" in Europe, eastern Canada, and the northeastern United States and similar disastrous changes in world weather patterns elsewhere--all in a period as short as two to three years.
Wars over access to food, water, and energy would be likely to break out between states, according to the report. "Disruption and conflict will be endemic features of life," according to the report. "Once again, warfare would define human life."
Even if climate change is more gradual, recent studies have argued that as many as one million plant and animal species could be rendered extinct due to the effects of global warming by 2050. A recent report by the world's largest reinsurance company, Swiss Re, predicted that in 10 years the economic cost of disasters like floods, frosts, and famines caused by global warming could reach $150 billion annually.
"Accelerated development of a portfolio of technologies could stabilize greenhouse gas concentrations, enhance global energy security, and eradicate energy poverty," noted David Jhirad, WRI's vice president for research. "We urgently need the political will and international cooperation to make this happen."
GLACIER MELT INDICATES GLOBAL WARMING CHANGES
A team of international scientists has returned to Australia from a three-month expedition to Antarctic with some alarming findings on climate change.
The scientists discovered a key glacier at in the middle of the Southern Ocean is melting much faster than expected.
The 28 scientists and support staff have arrived back in Australia after 10 weeks on remote Heard Island.
On the north-east coast of the island, glaciologists were disturbed to find Brown Glacier is melting at a faster rate than before.
In the 50 years to 2000, the glacier consistently lost half-a-metre of ice each year.
Australian Antarctic Division Glaciologist Dr Doug Thost says in the years since then it has been melting at almost four times that rate.
"The surface has been lowering just on average about two, just over two metres every year," Dr Thost said.
"It's a four-fold increase in that lowering rate."
Dr Thost says it is an early warning sign of global warming changes that scientists can expect further south.