"Rain bomb."

Those were the words used to describe the weather that hit BrisbaneThe third-largest city in Australia, situated on the east coast. on Sunday. Four inches of rain tumbled from the sky, causing flash floods. Roads were cut and train services halted; 2,145 homes and 2,356 businesses were left underwater, with over 10,000 more threatened as the waters rose. Almost 1,000 schools were unable to open yesterday.   

"No one has seen this amount of rain in such a short period of time," said the prime minister of QueenslandOne of the six states which make up Australia., Annastacia Palaszczuk. The state's head of emergency services, Carlene York, asked people to "stay off the roads unless you desperately have to be on them."

Brisbane also suffered terrible floods in 2011. At the time they were called a "once in a century event". We now know they were not.

The news will have come as no surprise to the Intergovernmental Panel on Climate Change (IPCC). Made up of some of the world's leading scientists, it published its latest reportOn average the IPCC issues a report every four years. yesterday - and the content was deeply worrying.

The report focuses on the effects of climate change, such as global temperature rises and extreme weather. It warned that global warming could reach 1.5C above pre-industrial levels within 20 years.

At that point, up to 14% of land-based species would face extinction. Those that live on coasts or are dependent on rivers are most at risk, with their habitats threatened by rises in sea levels and droughts.

Other dangers include heatwaves, the spread of disease and a fall in food production.

The report also examines whether people can adapt to cope with these problems - and if so, how. Forty per cent of humans are considered "highly vulnerable". According to one of the authors, Ed Carr, we need "transformational changes... everything from our food to our energy to transportation, but also our politics and our society".

The UNUnited Nations. An intergovernmental organisation based in New York that aims to maintain international peace and security. has already set a targetIt was set in the UN's Convention on Biodiversity. of making at least 30% of the world's land, ocean and freshwater into conservation areas. At present, the figures for each are just 15%, 8% and 21% respectively.

The suggestions for dealing with extreme weather include developing early warning systems and building seawalls and river barriers. Particular emphasis is put on "nature-based" solutions: in other words, harnessing the power of nature to combat global warming.

Tree-planting is an obvious example. As well as absorbing CO2, trees help protect land from flooding and prevent landslips. Similarly, mangroveA tree that grows in warm coastal water. swamps act as natural seawalls, while wetlands and peat bogs absorb excess water.

Developing these natural defences is predicted to cost half as much as building artificial ones. On a global level, it could save up to £180bn a year.

There are other advantages too. Nature-based solutions create local jobs, help combat pollution and restore wildlife habitats. Mangrove swamps increase fish stocks - but around a third of them have been damaged or torn up in recent decades. Restoring them would be a hugely beneficial project.

Yes: If nature were left to its own devices, climate change would not be a problem. Natural forces always find a way of balancing themselves. Human interference only makes things worse.

No: If climate change is to be halted, it will have to be through our own efforts. Trying to harness nature is a waste of time. We need drastic solutions. They can only be provided by human science.

Or... Science should study how nature works and take it further. Only by accelerating natural processes with the help of technology can we solve the problem quickly enough to survive.