Auckland faces tropical future as global warming heats up

By ANNE BESTON environment reporter

Temperatures could increase nearly 6 degrees C in the next 100 years, raising sea levels by a metre, says the most influential study of climate change yet produced.

A United Nations team of 150 top climate scientists blames humans for global warming in a report containing dire predictions for the future of the planet.

It sees disaster looming for many of the atolls of the South Pacific, and says Dunedin would get Auckland's climate, while Auckland would become a tropical city like Suva.

The report by the UN's powerful Intergovernmental Panel on Climate Change (IPCC), sponsored by the United Nations Environment Programme and the World Meteorological Organisation, takes a far more forceful stance on global warming than in its previous predictions, the last in 1995.

It concludes that global warming may take place twice as fast as expected, and comes at a crucial time in the debate over the environment.

The new United States President, George W. Bush, is considered hostile to international negotiations to reduce emissions.

Talks resume in Germany in May on cutting greenhouse gas emissions. The talks ended in November without agreement.

The panel of scientists from 100 countries, including five from New Zealand, concluded that warming over the past 50 years was due to industrial pollution and so-called greenhouse gases belching into the atmosphere.

"You won't get scientists saying anything stronger than that," said New Zealand's lead author on the report, Dr Jim Salinger, of the National Institute of Water and Atmospheric Research.

"The upper limit of the predictions would totally change the face of the Earth. The planet will be the warmest it's been in millions of years."

The scientists predict that temperatures will rise by between 1.4 and 5.8 degrees C by 2100, melting the icecaps and raising sea levels by almost 1m, jeopardising many of the atolls of the South Pacific.

Rising oceans would force the evacuation of millions. The tiny island nation of Kiribati, already polluted and eroded by the encroaching waves as it struggles to survive just 2m above sea level, would become uninhabitable for its 92,000 people.

The IPCC report, issued in Shanghai yesterday, said the biggest temperature rises were occurring nearer Earth, in the lowest 8km of atmosphere.

Snow cover on lakes and rivers in the Northern Hemisphere has decreased by 10 per cent since the 1960s and Arctic sea ice thickness has decreased by 40 per cent.

Dr Salinger said the lack of data from Antarctica, where satellite measurements of the ice had been done only since the 1970s, meant it was impossible to say if Antarctica had experienced a similar decrease.

Carbon dioxide concentrations in the atmosphere from burning fossil fuels have increased by a third since 1750, the report says.

Carbon dioxide is the main culprit in the "greenhouse effect," where gases which accumulate above the Earth trap warmer air beneath them, heating the planet's surface.

The world climate negotiations on reducing COinf2 ended in disarray late last year as countries bickered over reducing their emissions.

The United States is the biggest producer of greenhouse gases, followed by China.

The scientists warned that rising temperatures and sea levels could disrupt fishing, farming and forestry, kill much of the world's coral reefs and flood massive areas of heavily populated coastal areas in Bangladesh and Egypt.

Extreme weather, including floods, heatwaves and cold snaps, would become more likely, Dr Salinger said.

Climate sceptics, who have increasingly questioned the science of global warming, were losing the battle, said Professor Blair Fitzharris, a climatologist at the University of Otago.

"At the heart of the debate is our economic system. That's why it's very hard for politicians to act, because alternatives for energy and farming might be more costly."

But climate sceptic Dr Vince Gray of Wellington called the report "guesswork" and "almost a fraud."

He said the claim that temperatures might rise by 6 degrees C was based on a number of scenarios that were virtually arbitrary.

"They're not actually predictions or forecasts, just possibilities."

More than 500 scientists reviewed the findings and the final report was unanimously accepted.

Herald Online feature: Climate change

Intergovernmental Panel on Climate Change

* Draft summary: Climate Change 2001

  (requires Adobe Acrobat Reader)

United Nations Environment Program

World Meteorological Organisation

Framework Convention on Climate Change