The Earth has a global average temperature. Scientists measure how much it has risen compared with the late 1800s, aka pre- industrialisation, aka before factories, coal and cars began adding heat-trapping gases to the air. Before the Industrial Revolution, the air held about 280 parts of CO₂ per million. It is now over 400. CO₂ stays in the air for a very long time, so the more we add, the warmer it gets, and it only cools if the amount in the air falls.
In 2015, countries signed the Paris Agreement and promised to hold warming well below 2°C and to try to stay under 1.5°C. The lower number was added because scientists found that risks keep rising with each extra tenth of a degree.
Today the planet is about 1.4°C warmer than it was pre-industrialisation. A latest report by the International Cryosphere Climate Initiative (ICCI), titled “State of the Cryosphere 2026, The Cost of Overshoot”, says that the world will pass 1.5°C. This is called overshoot.
That number may sound small but its impact is not. Think of a human body: a rise of 1.5°C is the difference between feeling fine and being unwell. A planet is the same. Because it is an average across oceans, deserts, ice and cities, a small shift in the average means large shifts in places: longer heatwaves, heavier storms, melting ice.
The debate has therefore changed. It is no longer “can we avoid crossing 1.5°C?” It is “how high do we go, and how long do we stay there?”
The answer to that is two future possibilities. In a limited overshoot, where we make ambitious efforts to reach net-zero emissions by mid-century and then remove carbon from the air, global warming will peaks at about 1.7°C and the world is back below 1.5°C by 2100. If we don’t manage that, the warming peaks at about 3°C and the world does not return below 1.5°C until around 2250.
But we cannot wait around for this “bringing back.”
While air temperature can fall fairly soon after carbon in the air falls, ice cannot snap back that fast. A glacier that has gone does not return on a timeline as we count in comparison to a human lifetime. The great ice sheets respond over centuries. The report says that even if temperatures return to 1.5°C, large amounts of ice are already committed to loss, and seas will keep rising for centuries. That is why every year spent above 1.5°C sounds alarm.
Why ice is at the centre of this
The report comes with a stark warning on its front page that “We cannot negotiate with the melting point of ice.”
The cryosphere, as in the frozen parts of the planet such as the ice sheets in Greenland and Antarctica, mountain glaciers and snow, sea ice, permafrost (frozen ground) and the cold polar oceans, is at the centre of this issue because they:
– raise sea levels when they melt, putting about a billion people living within 10 metres of the sea at risk;
– store the water that about three billion people depend on seasonally;
– reflect sunlight, so losing them makes the planet warm faster;
– hold huge amounts of carbon in frozen ground that is released when it thaws.
Disclaimer : This story is auto aggregated by a computer programme and has not been created or edited by DOWNTHENEWS. Publisher: deccanchronicle.com
