In December 2015, world leaders will meet in Paris for the UN climate change conference, COP21, to negotiate agreements on a radical reduction in carbon emissions.

The science is clear: unless we can keep the rise in global temperatures below 2 degrees Celsius, catastrophic and irreversible climate change is likely. For the most vulnerable countries, that figure is likely to be 1.5C - and leading scientists such as Kevin Anderson, from the Tyndall Institute, say we are heading that way at a much faster rate than expected.

Most scientists agree that Paris is the planet's last chance saloon. Without immediate and radical reductions in carbon emission, we are close to a tipping point.

This programme investigates what a 2C rise in temperature actually means for the planet and why governments have allowed this to happen - despite dire warnings about the effects of greenhouse gases since the 1980s.

Nick Clark, the presenter of earthrise, embarks on a global journey to understand the consequences of increasing temperatures. He begins in the Pacific island nation of Kiribati. It is one of dozens of small, low-lying nations at risk of being totally submerged if sea levels continue to rise due to global warming. He speaks to the President of Kiribati, Anote Tong, who believes climate change is the biggest moral challenge for humanity.

In the US, James Hansen, the famous climatologist and former NASA scientist, tells Nick about his quest to sue the US government for not taking the steps that are needed to keep warming below 2C.

In the Swiss Alps, Yeb Sano, the former negotiator for the Philippines government, is leading a 1,500 kilometre pilgrimage - a long and gruelling march - from Rome to the climate summit in Paris to campaign for greater international action on reducing global emissions. Nick speaks to him and his brother AG Sano about their country's experience of global warming.

This film was first broadcast on Al Jazeera English in November 2015.

Source: Al Jazeera