The veteran broadcaster warns in a BBC documentary called Climate Change – The Facts, that the natural world faces “irreversible damage” unless drastic action is taken over the next decade to limit global warming.
Sir David warns in the film, which was broadcast for the first time on the 18th April, that some societies may collapse unless swift and decisive action is taken by governments.
“It may sound frightening, but the scientific evidence is that if we have not taken dramatic action within the next decade, we could face irreversible damage to the natural world and the collapse of our societies,” he said.
In the program, Sir David talks to a range of scientists to find out what is already happening to the world as a result of climate change.
Dr. Peter Stot from the Met Office said that the world is already 1C warmer than before the industrial revolution.
“What we have seen is the steady and unremitting temperature trend. Twenty of the warmest years on record have all occurred in the last 22 years,” he said.
Professor Andrew Shepherd from the University of Leeds warned that ice caps in Antarctica and Greenland are already shrinking rapidly.
“In the last year we’ve had a global assessment of ice losses from Antarctica and Greenland and they tell us that things are worse than we’d expected. The Greenland ice sheet is melting, it’s lost four trillion tonnes of ice and it’s losing five times as much ice today as it was 25 years ago,” he said.
In some places of the world people are already having to deal with the adverse effects of climate change. In Louisiana in the southern United States, sea water is rising so quickly that people are having to abandon their homes. Roughly an area the size of a football field is being lost to rising waters every 45 minutes.
Still Time to Avert Disaster
But the film is not without hope and Sir David says that if dramatic action is taken over the next decade then the rise in temperatures can be limited to just 1.5C this century.
The technology is already there as is shown by the rapid growth of renewable energy. Wind power is now as cheap to produce as fossil fuels and technology has also been developed to remove and bury carbon dioxide underground.
But the action that is required costs money and this will require political will decisive action from politicians.
“This is the brave political decision that needs to be taken. Do we incur a small but not insignificant cost now, or do we wait and see the need to adapt. The economics are really clear on this, the costs of action are dwarfed by the costs of inaction,” said Chris Stark from the UK’s Committee on Climate Change.