'Dire warning' issued over global climate change » Environment » 24dash.com

The world's top scientists today issued the direst warnings yet about the threat from climate change.

After six years of research, they predict the average world temperature will rise by about three degrees by the end of the century - with potentially devastating consequences for melting ice caps and rising sea levels.

They also make the strongest causal link so far between human behaviour and global warming.

The evidence in a new report published in Paris has the finest pedigree - the work of the Intergovernmental Panel on Climate Change (IPCC), which draws together 2,500 scientists from more than 130 countries.

The study highlights the strengthening international scientific conviction that human activity is largely responsible for the rise in the Earth's surface temperature.

The IPCC's previous assessment in 2001 rated the link between the warming planet and the actions of its inhabitants as "likely" - IPCC-speak for a probability rate of 66-90%.

The new report revises that to "very likely" - a greater than 90% chance that mankind is to blame.

That adds credence to those who insist that the recent unseasonal warm spells are more than simply atmospheric blips.

The London-based International Institute for Environment and Development said the IPCC report delivered "the most conclusive evidence yet" that human activities are causing dangerous climate change."

Institute Director Camilla Toulmin said: "It shows in stark

terms that time is running out to cut greenhouse gas emissions and to help vulnerable communities prepare for the impacts ahead, some of which are already unavoidable.

"While the developing countries have contributed least to the problem, they will suffer most from effects such as rising sea levels, droughts and flooding. A collective failure to correct this global injustice is likely to trigger social, political, economic and environmental problems that will be felt around the world."

Ms Toulmin added: "The scientific and moral arguments for urgent action are now over. It is up to political and business leaders, as well as citizens around the world, to seize this challenge and work together to tackle the biggest challenge that humanity has ever faced."

Friends of the Earth also called for action in the wake of the latest assessment: clearer-than-ever evidence:

"The IPCC report scientifically confirms the extent of this man-made crisis already hitting people across the world, and makes bleak predictions for the future - more intense storms, droughts and rising sea levels." said FoE Climate and Energy Campaigner Jan Kowalzig.

"We can no longer afford to ignore growing and compelling warnings from the world's leading experts."

He said the European Union should use a summit next month to "swap grand words for serious action" on climate change.

Last month the European Commission proposed the first-ever EU common energy policy, with a target of capping inevitable temperature rises at two degrees.

"EU leaders must go for a 30% emissions reduction target, which would be just enough to avert the worst of climate change." added Mr Kowalzig.

"The current unilateral proposal of cutting 20% by 2020 compared to 1990 levels simply won't keep global temperature increase below the all-important two degrees Celsius. And, let's face it, if the EU doesn't aim high on cutting emissions, who else will?"

Three weeks ago a Commission report predicted that an average global temperature rise of 2.2 degrees would kill an extra 11,000 people in Europe a year within ten years, and from 2071 there would be 29,000 extra deaths annually in southern Europe.

Even in relatively cold northern Europe 27,000 people would die a year due to the warmer climate.

But the Commission also warned that there was now a more than 50% chance that global temperatures would actually rise this century by more than five degrees centigrade.

The latest IPCC analysis puts the likely future average rise at anything between 2 degrees and 4.5 degrees.

Today's report, the first of four IPCC volumes to be published this year, concentrates on the expected world impact of climate change.

Later parts will set out more detail on possible remedies.

American government scientist and IPCC vice-chairman Dr Susan Solomon told a press conference in Paris that there was no doubt now about a link between human behaviour and global warming.

Unveiling today's report in Paris, she declared: "Global concentrations of greenhouse gases have increased markedly since 1750. They are now far far above the values seen in the ice cores in many thousands of years."

Dr Solomon went on: "We have very high confidence that the net effect of human activity since 1750 has been one of warming.

"The dramatic rise (in temperatures) is so different from behaviour in thousands of years.

"Most of the increase since the mid-20th century is due to the observed increase in greenhouse gas concentrations. This discernible human influence extends to ocean warming, temperature extremes and wind patterns."

The overall impact was "affecting the Earth's energy balance".

Dr Solomon said the expectation was estimated that in the next two decades average temperatures could rise by 2.2C.

Even if concentrations of greenhouse gases were constant at the levels of the year 2000, an average temperature increase of one-tenth of a degree per decade was to be expected.

The IPCC report forecasts temperatures will probably rise by between 1.8-4C this century - with a rise of as much as 6.4C "possible".

The resulting ice cap melt - with Arctic ice in the sea disappearing altogether in the second half of this century - could increase sea levels by up to 43cm (17 inches).

That would destroy many coastal regions around the globe - including almost one-third of Africa's coastal infrastructure, according to some analysts. Tropical storms and heatwaves would become more frequent.

IPCC chairman Dr Rajendra Pachauri said the most up-to-date statistics compiled in the report indicated drastic behaviour patterns affecting the planet: "Based on scientific evidence, we are in a sense doing things that have not happened in 650,000 years."

The report involved thousands of experts, including 600 authors from 40 countries and 600 reviewer assessing the latest available figures on global warming.

It was finally approved after intense discussion in Paris between 300 IPCC delegates from 113 countries.

Now, said Dr Pachauri, the document had "the stamp of acceptance" of all the governments of the world.

He said more reports would follow later this year - four in all - followed by a 30-page "synthesis report" in November.

Between them, the reports will cover not just cause and effect, but also set out options for avoiding the scientists' most worrying predictions.

He said: "If you see the extent to which human activities are influencing the climate system, the options for mitigating greenhouse gas emissions appear in a different light, because you can see what the costs of inaction are."

Environment Secretary David Miliband described the report as a blow for "climate change deniers" - and it showed the need for urgent international political action.

He said: "The report confirms our concerns that the window of opportunity to avoid dangerous climate change is closing more quickly than previously thought.

"It is another nail in the coffin of the climate change deniers and represents the most authoritative picture to date, showing that the debate over the science of climate change is well and truly over.

"What's now urgently needed is the international political commitment to take action to avoid dangerous climate change. This has been absent so far.

"Man-made climate change poses an increasing risk to people and business across the globe. It will have disastrous consequences if we don't act now. The economic evidence, following the Stern Review, is clear that tackling this challenge is both achievable and affordable."

Sir David King, the UK's chief scientific adviser said: "Since the publication of the last assessment of the IPCC in 2001, our understanding of man-made influences on climate and how the current climate is changing has improved.

"There is now much stronger evidence that the emissions of greenhouse gases, produced, for example, as a result of fossil fuels burnt for transport, heating and industry, as well as a result of deforestation, are responsible for the warming observed since pre-industrial times. The Earth has warmed by 0.74C since the beginning of the 20th century".

Dr Richard Wood, senior climate scientist at the Met Office, who was involved as a "co-ordinating author" in today's report, said the world now faced a "huge" climate change challenge.

"This report is a landmark in climate research. It gives us a more confident view of what we might expect in the future."

He said the Met Office had made great advances in such research, but more detailed regional information was still needed to help politicians and businesses plan for adapt to potentially rapid and dramatic climate change.

That required a combination of first- science with increasingly powerful "supercomputers".

Met Office chairman Robert Napier added: "The challenge is that climate change is not linear. The planet and all of us face uncertain consequences as temperatures rise.

"We need to make sense of this challenge - not to scare or alarm but to present with scientific validity the probabilities of what might happen. The Met Office has the ability, the reputation and the responsibility to do this."

Mayor of London, Ken Livingstone, said: "The Intergovernmental Panel on Climate Change (IPCC) report is unequivocal about the threat of climate change. It cannot be dismissed as apocalyptic scaremongering by a fringe group. This report has been agreed by the governments of over 100 countries - including climate change sceptics like the USA and Saudi Arabia - as well as by over 2,000 leading scientists.

"We now understand the threat of climate change and that this warming trend, which will see temperatures increase by at least three degrees in our lifetime and our children's lifetime is directly caused by human behaviour. As the Stern Review identified, carbon pricing is the key mechanism to stimulate the sorts of reductions we need, and the Government must move to bring large commercial and public sector bodies into a carbon-trading scheme as soon as possible.  Voluntary action alone will not be enough.

"In London we have made cutting carbon emissions our number one priority, including becoming the only major city in the world to have achieved a "modal shift" - getting people out of the cars and onto public transport as well as more cycling and walking. We are working with cities across the world and have established the C40 group of cities to accelerate programmes to cut emissions. In 2007 we will become the first major city to set out a comprehensive plan to achieve the serious carbon emission cuts necessary to avert catastrophic climate change.

"It is 19 years since the United Nations formed the Intergovernmental Panel on Climate Change. Yet, since then global greenhouse emissions have continued to rise. Today's report must be an immediate call to action by governments at all levels all around the world to make cutting carbon emissions their number one priority as we have already done in London."

Forum for the Future, Chief Executive Peter Madden, said: "We can never know the future for certain, but this latest IPCC report effectively ends the debate about whether climate change is happening, and whether human activity is the cause. The answer is 'yes' on both counts, and the focus now has to be on both stopping climate change getting worse and adapting to the effects already in the pipeline".

"The good news is that awareness of the issue is rising exponentially. With 91% of the UK's university applicants believing climate change will affect them personally in the next 25 years - mostly for the worse - it's clear that the message has got through. This provides a clear mandate for business and the public sector to move forward and quickly."