Climate change: Outlook gloomy but it's not too late to slow our destruction of the planet

Tom Clarke

Former Science Editor

Thinking of buying a beach house? Think again.

Sea levels are rising faster than we thought, and extreme weather events like storm surges that used to occur once every century could be occurring every year by 2050, according to the latest report from the world's climate scientists.

The report looks at the impact of our warming planet on ice, locked up in ice sheets and glaciers, and the oceans which cover more than 70% of the Earth.

It finds well over a billion people living in coastal regions and high mountain areas dependent on mountain glaciers are facing a direct threat - even if efforts to severely cut carbon dioxide emissions begin now.

"The world’s ocean and cryosphere have been ‘taking the heat’ from climate change for decades, and consequences for nature and humanity are sweeping and severe," said Ko Barrett, Vice-Chair of the Intergovernmental Panel on Climate Change which produced the report.

"The rapid changes to the ocean and the frozen parts of our planet are forcing people from coastal cities to remote Arctic communities to fundamentally alter their ways of life."

Sea levels could rise significantly over next century

Flooding and sea level rise are set to become more common as climate change accelerates. Credit: AP

The report finds sea level is rising fast, and will only get faster the longer we delay in reducing fossil fuel use.

Sea level is currently rising at around 3.6mm per year.

If, by some means, we can keep global warming below two degrees celsius by the end of the century, sea levels will still rise by 30-60 cm.

If we exceed that limit, which we're currently well on course to do, it could be much higher, sea levels could rise up to a metre.

At those temperatures, the Greenland and Antarctic ice sheets will be in retreat, seas could be up to 5.4 metres higher by 2300.

Warmer oceans can hold less oxygen, become more acidic and don't mix as well.

This is having a direct impact on marine life.

Coral reefs will all but disappear by 2100, and major fisheries on which we all depend could be lost.

Sea ice, which currently covers much of the arctic, will be lost.

Stronger storms will batter Earth for future generations

Warmer oceans mean stronger storms ripping through homes and communities. Credit: AP

Around 90% of all the extra heat from global warming is being absorbed by the oceans. And that energy is what drives storms.

Combine more severe storms with higher sea levels, and you get a major increase in the size and intensity of storms like hurricanes and tropical cyclones.

Without serious efforts to adapt, damage to coastal property and defences could increase between 100 and 1,000 times by 2100, the report warns.

Climate change now inevitable but worst can be avoided, report says

Retreating mountain glaciers will directly affect people dependent on them for water for both drinking and agriculture.

Glaciers in the European Alps will have disappeared in a century or two, whether we make cuts to emissions now or not.

Melting permafrost in the polar regions could emit more greenhouse gases into the atmosphere, exacerbating the warming already being driven by human activities.

While some of the impacts described in the report are now inevitable. The very worst of them can still be avoided.

"If we reduce emissions sharply, consequences for people and their livelihoods will still be challenging, but potentially more manageable for those who are most vulnerable," said Hoesung Lee, Chair of the IPCC said.

"We increase our ability to build resilience and there will be more benefits for sustainable development."

The outlook for the planet might be getting gloomier, but the logic remains the same: We know what we have to do to prevent climate change becoming very expensive and very dangerous.

And ignoring it will only make it more expensive, and more dangerous for future generations.