BELGIUM:More than 100 million people across the globe could be flooded every year within 75 years due to global warming, a new report by climate change experts to be published this morning is expected to say.
The report, by the Intergovernmental Panel on Climate Change (IPCC), which will be published in Brussels, is also expected to predict that up to 20 per cent of the Earth's animal and plant species face extinction if temperature rises predicted occur very quickly.
According to the report, which examines the impact of climate change over the next century, tens of millions of people will be affected by water shortages due to climate change.
It warns the areas of the globe facing the greatest impacts from climate change happen to be poorer regions with little ability to adapt.
Throughout the week representatives from more than 200 countries have been working on the final draft of the summary part of the document in Brussels.
There have been ongoing tensions between representatives of various countries over aspects of the report, as some sought to dilute the findings.
Meetings have been stretching into the early hours in a bid to find compromise on some of the findings.
Overall, however, the report will predict wet areas in northern and tropical latitudes will become wetter while traditionally drier regions will see less rainfall.
It says that, from 2080, more than 100 million people a year in coastal areas around the globe will face flooding from a combination of two climate change factors: rising sea levels of more than half a metre and increased tropical storm and hurricane activity.
Coastal cities in developed countries, especially in the US, are at risk from flooding, but the greatest impact will be in poorer regions across the globe.
Large river-delta areas and small low-lying islands have been identified as being at particular risk.
The report is not expected to identify specific regions, but the Bay of Bengal, Maldives, and some Caribbean islands are seen as extremely vulnerable.
Access to fresh water is also going to become an issue in coastal areas, despite the increased rainfall from tropical storms, the report warns.
Coastal flooding is expected to contaminate fresh water sources with sea water, making it undrinkable.
The report also warns that access to water will become one of the single biggest issues.
There is potential for severe water shortages in dry areas such as sub-Saharan Africa, with potentially significant reductions in rainfall.
This could prompt food shortages and, in turn, large-scale migration from some regions by the end of the century if temperature rises exceed 2.5 to three degrees Celsius.
However, the report says that there will be no significant deterioration in agricultural productivity up with a rise to a 2.5 or three degrees.
With a rise up to three degrees there will be changes in the types of crops sown, as farmers adapt to temperature shifts, with no significant impact on production levels.
But the report warns that temperature rises in excess of three degrees will lead to heat stress and water shortages in many areas, including high-yield regions, with food shortages resulting.
In the report, which was still being finalised last night, scientists warn that animal and plant species face extinction if temperature increases occur rapidly.
A temperature rise of more than 2.5 degrees over the next 50 years could prompt such an environmental catastrophe.
These experts believe up to one-fifth of all species will be unable to adapt to such a rapid temperature rise, and will face extinction.
The report highlights the potential of accelerated global warming from what the scientists describe as "positive feedback".
This could result from the natural environment being less able to absorb carbon dioxide at higher temperatures, which will in turn lead to higher levels of the gas remaining in the atmosphere. Evidence of this phenomenon emerged during the European heat wave of 2003.
There is particular concern that the Amazon and other tropical rain forests could suffer from this phenomenon.
More than 1,000 scientists have contributed to the report, which is based on more than five years of research.
It is the second report from the panel this year. In February the panel produced its first report on the causes of climate change and concluded that it was 90 per cent likely to be due to human activity.
A third report will be released next month, focusing on the measures that need to be taken in order to minimise the impact of climate change on people around the world.