
The Great Barrier Reef will be so degraded by warming waters that it will be unrecognizable within 20 years. Charlie Veron, former chief scientist of the Australian Institute of Marine Science, told The Times: “There is no way out, no loopholes. The Great Barrier Reef will be over within 20 years or so.” Once carbon dioxide had hit the levels predicted for between 2030 and 2060, all coral reefs were doomed to extinction, he said. “They would be the world's first global ecosystem to collapse. I have the backing of every coral reef scientist, every research organization. I've spoken to them all. This is critical. This is reality.”

Teeming with millions of species and one-fifth of the world's fresh water, the Amazon is the world's largest tropical rainforest. However, global warming and deforestation are reversing the forest's role as a carbon sink, converting 30-60% of the rainforest into dry savannah. Projections show the forest could disappear completely by 2050.

Scientists are seeing signals that the Sahara desert and surrounding regions are greening due to increasing rainfall. If sustained, these rains could revitalize drought-ravaged regions, reclaiming them for farming communities. This desert-shrinking trend is supported by climate models, which predict a return to conditions that turned the Sahara into a lush savanna some 12,000 years ago.

It isn't only reefs and low-lying islands that are under threat from global warming. In fact, a major threat is for those large urban areas which are at risk of eventually being submerged underwater. This is caused by a change in sea levels that occurs when global warming takes place, resulting in coastal cities being destroyed by flooding. Dozens of the world's cities, including London and New York, could be flooded by the end of the century, according to research which suggests that global warming will increase sea levels more rapidly than was previously thought. London is one of the major world capitals at high risk of this type of flooding, as depicted in this shot from the 2007 movie Flood. Scientists say that the city could be under water as early as within the next one hundred years.

The lowest and flattest country in the world is suffering coastal erosion, and could find itself submerged if sea levels carry on rising, with the islands growing smaller and smaller. This extreme prediction is a devastating prospect for residents and bad news for the tourists who descend on its soft white beaches and warm waters each year. Scientists give it only about one hundred years before it completely disappears into the ocean surrounding it.