No one knows how much warming is "safe". What we do know is that climate change is already harming people and ecosystems. Its reality can be seen in melting glaciers, disintegrating polar ice, thawing permafrost, changing monsoon patterns, rising sea levels, changing ecosystems and fatal heat waves.
Scientists are not the only ones talking about these changes. From the apple growers in Himachal to the farmers in Vidharbha and those living in disappearing islands in the Sunderbans are already struggling with the impacts of climate change.
But this is just the beginning. We need to act to avoid catastrophic climate change. While not all regional effects are known yet, here are some likely future effects if we allow current trends to continue.
Relatively likely and early effects of small to moderate warming:
Natural systems, including glaciers, coral reefs, mangroves, Arctic ecosystems, alpine ecosystems, Boreal forests, tropical forests, prairie wetlands and native grasslands, will be severely threatened.
Longer term catastrophic effects if warming continues:
Greenland and Antarctic ice sheets are melting. Unless checked, warming from emissions may trigger the irreversible meltdown of the Greenland ice sheet in the coming decades, which would add up to a seven meters rise in sea-level over some centuries. New evidence showing the rate of ice discharge from parts of the Antarctic means that it is also facing a risk of meltdown.
Never before has humanity been forced to grapple with such an immense environmental crisis. If we do not take urgent and immediate action to stop global warming, the damage could become irreversible.