Latin America and the Caribbean face a greater risk of more natural disasters because of environmental degradation and climate change, campaigners warn.
Extreme weather is less predictable and more intense, the report says
A report by a coalition of environment and aid groups said the region's weather was becoming less predictable and often more extreme.
Evidence showed many areas were more vulnerable because depleted ecosystems were struggling to adapt, they argued.
The groups said efforts to end poverty were being undermined as a result.
The report, Up in Smoke? Latin America and the Caribbean, presented evidence it said showed that the livelihoods of millions of people in the region were at risk, including:
- Increased storm intensity - the 2005 hurricane season was "one of the most active and destructive in history"
- Water shortages - changes to glacier melt in the Andes were affecting river flows and threatening water supplies, leading to a greater risk of disputes
- Illegal logging and deforestation - linked to increased carbon emissions, and leaves area prone to a greater risk of flooding
The report's author, Andrew Simms, from the New Economics Foundation (Nef), said the findings highlighted how climate change was having an impact on global efforts to eradicate poverty.
"The region has had to deal with highly variable climates for many centuries. It has developed very resilient forms of agriculture based upon high levels of diversity of crops, which are adapted to grow in a wide range of microclimates.
"The danger that now seems to be facing people in the region is that those conditions could become more permanent and more extreme," he said.
The 2005 Atlantic hurricane season saw an unprecedented 27 tropical storms, 15 of which went on to become hurricanes. The most devastating was Hurricane Katrina, which claimed more than 1,000 lives when it struck the US Gulf coast.
The US National Oceanic and Atmospheric Administration (Noaa) had predicted that there would be up to nine hurricanes.
A hurricane is a spinning vortex of winds swirling round a eye of very low pressure
Warm, moist air is drawn upwards around the eye
Cooler dry air is sucked downwards by the low pressure centre
Banks of thunderstorms surround the edges
For the 2006 season, Noaa's initial forecast predicted 13-16 named storms, four of which would go on to become "major storms".
In August, however, officials revised their forecast, saying that there would be 12-15 named storms. But this was still above the long-term average of 11.
Uncertainty still remains within the scientific community as to whether there is a direct link between human-induced climate change and increased intensity and frequency of tropical storms.
Commenting on the coalition's report, US climate change researcher Timmons Roberts, from the College of William and Mary, Virginia, warned that overstating the risks could prove to be counterproductive.
"Some points may be exaggerated or so uncertain as to make scientists uneasy about making such claims, especially about future disasters."
But Professor Roberts, who is currently working in the UK, did agree that the risks facing the region were extremely serious.
Diane Liverman, director of the Environmental Change Institute at Oxford University, UK, welcomed the coalition's decision to focus on the region.
"I am sometimes concerned that the understandable focus on African climate and development issues has meant that we haven't paid attention to the millions at risk in other regions of the developing world."
But Professor Liverman, who has studied climate vulnerability in Mexico for the past 20 years, was critical of the report for overlooking research by climate scientists in the region.
"Organisations such as the Inter American Institute for Global Change Research (IAI) and researchers in many universities have done a lot of research on climate and environmental change in the region; little or none of which is referenced or used in the report."
Call for action
The coalition, whose 20 members include Tearfund, Greenpeace and WWF, said there were three main challenges that needed to be addressed:
- stopping and reversing further global warming
- how to live with global warming that cannot be stopped
- the need for a "climate friendly" development framework that delivers an equitable share of natural resources
"Currently, we do not have a meaningful emissions reduction target that will prevent runaway climate change, " Mr Simms said.
"We also do not have an idea of the scale of the resources needed to help developing countries deal with it."
He added: "We must apply a climate test to how the world does business. If we don't then we will probably inadvertently make things much worse."