What the UN's 'overshoot' warning means: the emissions gap report explained, and where India fits

What is the emissions gap?

It is the distance between what countries have promised and what the climate needs.

Under the 2015 Paris Agreement, governments agreed to hold warming well below 2C above pre-industrial levels and to try to limit it to 1.5C. Each country sets out its own plan, known as a nationally determined contribution, or NDC. Every year the UN Environment Programme adds up those plans and the policies actually in place, works out where they would take global emissions, and compares that with the path needed to hit the temperature goals. The difference is the gap.

This year’s report says the gap has grown so wide that one of those goals can no longer be met on time.

What does “overshoot” mean?

That warming will pass 1.5C before, at best, coming back down.

The report’s most hopeful scenario has temperatures peaking at 1.7C to 1.8C around the middle of the century and then falling back to 1.5C or below by 2100. Even that has only about a 50% chance of working. “Overshoot is not surrender,” UN Secretary-General António Guterres said, urging governments to keep it “as small and as short as possible”.

The size and length of the overshoot matter because damage builds with every fraction of a degree. More intense heatwaves, heavier rain and faster melting of ice are expected at 1.8C than at 1.5C, and some changes, such as the loss of coral reefs or ice sheets, may not reverse when temperatures fall.

What would it take to come back to 1.5C?

Cuts far steeper than anything on the table. Global emissions would have to fall 18% from 2025 levels by 2030, 45% by 2035 and 69% by 2040. The share of coal in world energy supply would need to drop by at least 55% by 2035, oil by 15% and gas by 5%, with methane emissions at least 25% lower.

On top of that, the world would have to pull about 320 billion tonnes of carbon dioxide out of the air this century and store it permanently, roughly eight years of today’s emissions. The authors call that approach uncertain, because the technology to do it at scale does not yet exist.

Is there any good news?

Yes, on clean power. Renewable capacity around the world has grown about three times faster since 2015 than was expected at the time, and solar about seven times faster. That is a large part of why projected warming is lower than it was a decade ago. The setback, UNEP said, has come from politics, including the United States’ withdrawal from the Paris Agreement.

Where does India fit?

India’s targets are framed around intensity, not an absolute cut. In March the Union Cabinet approved India’s NDC for 2031 to 2035. It commits to cutting the emissions intensity of GDP, the emissions produced for each unit of economic output, by 47% from 2005 levels by 2035, and to raising the share of non-fossil sources in installed power capacity to 60%. India had already reached about 52.57% in February. It also aims to build an additional carbon sink of 3.5 to 4 billion tonnes through forest and tree cover.

Because India’s economy is growing fast, an intensity target allows its total emissions to keep rising for some years, even as each rupee of output becomes cleaner. India’s long-term goal is net zero by 2070. New Delhi has long argued that countries which industrialised first, and whose emissions per person remain far higher, should cut fastest and pay for others to adapt.

What happens next?

The numbers go to the next UN climate summit, COP31, next month. Governments will be under pressure to explain how they will close a gap that, on their own plans, barely narrows by 2035. Inger Andersen, UNEP’s executive director, put the task plainly: “We must pull out all the stops to minimise peak warming and return to 1.5C by the end of the century.”