Today an international group of hundreds of  climate scientists released a report on how climate change will affect the world, and what might be done to adapt to it.

The story so far

The report from the Intergovernmental Panel on Climate Change (IPCC) is the second of three reports. It updates the panel’s last bumper report, released in 2007.

Scientists know that carbon dioxide is a greenhouse gas, meaning it traps heat in the atmosphere and oceans.

Over time, scientists have come to understand more about how gases like carbon dioxide, emitted when people burn fossil fuels like oil and gas, affect the climate.

The first instalment of the IPCC’s report, released last September, says scientists are more sure than ever – 95 per cent certain – that humans are causing extra warming. And as a result, oceans, land and atmosphere are getting warmer, snow and ice is melting and sea levels are rising.

The new report

Scientists now know much more about the risks the world faces as the climate changes, too.

The new report, out today, says climate change is already contributing to problems like flooding, disruption to farming and food supply and species migration and extinction.

Changes in the natural world have been easiest to measure so far. Already, plant and animal species are migrating to unfamiliar new territories. Some are trying to escape to cooler climes.

Meanwhile, others are taking advantage of warmer temperatures further north: the Arctic is becoming greener, and cooler places can expect invasions from unfamiliar species including pests and diseases.

In the future, the report says rising temperatures are likely to contribute to slowed economic growth and shakier food security, along with other problems.

A risky mix

It’s the mixture of climate change with existing stresses on human and natural environments that poses the greatest threat in the future.

The gap between rich and poor may be made worse as a result of climate change. The world’s poorest and most marginalised people are likely to be most vulnerable. Meanwhile, richer countries and communities will find it easier to adapt to conditions like extreme weather events – though even the world’s richest countries won’t be able to adapt to everything climate change throws them.

Climate-related risks may also exacerbate tensions – though these are most likely to occur within countries than between them. People may be forced to migrate to escape drought or flooding, while pressure on resources like food and water might create tensions between communities.

Adapting to the future

But humans can act to limit climate change’s effects. If governments work to cut their emissions and adapt to new conditions in the meantime, there are opportunities to make societies more equal and resilient.

The report concludes that if that starts to happen soon, the worst impacts can be avoided.