Leaked IPCC draft report warns of accelerating climate devastation

In June 2021, a 4000-page draft report of the IPCC was leaked to the press. It is a part of the IPCC’s Sixth Assessment Report to be published in stages from late 2021. The document warns of sweeping impacts on weather events, food, ecosystems, and disease—changes expected even if global temperature rise is kept under the Paris climate agreement's second threshold of 2°C. It also calls for systems-wide changes to avert a worst-case climate scenario.

The key messages of the leaked report were:

• With 1.1 deg C of warming clocked so far, the climate is already changing. 
• Global warming will trigger tipping points in Earth’s natural systems, which will lead to widespread and possibly irrevocable disaster, unless action is taken urgently.
• Tipping points are triggered when temperatures reach a certain level, whereby one impact rapidly leads to a series of cascading events with vast repercussions. The draft details at least 12 potential tipping points. Some examples are:
• As rising temperatures lead to the melting of Arctic permafrost, the unfreezing soil releases methane, a powerful greenhouse gas that in turn causes more heating.
• The melting of polar ice sheets, which once under way may be almost impossible to reverse even if carbon emissions are rapidly reduced, and which would raise sea levels catastrophically over many decades.
• The possibility of the Amazon rainforest switching suddenly to savannah, which scientists have said could come quickly and with relatively small temperature rises.
• The impacts are likely to be much closer than most people realise and will fundamentally reshape life in the coming decades even if greenhouse gas emissions are brought under some control.

• Tens of millions more people are likely to face chronic hunger by 2050, and 130 million more could experience extreme poverty within a decade if inequality is allowed to deepen.
• In 2050, coastal cities on the “front line” of the climate crisis will see hundreds of millions of people at risk from floods and increasingly frequent storm surges made more deadly by rising seas.
• Some 350 million more people living in urban areas will be exposed to water scarcity from severe droughts at 1.5 degrees Celsius of warming – 410 million at two degrees Celsius.
• That extra half-a-degree will also mean 420 million more people exposed to extreme and potentially lethal heatwaves.

• Species extinction, more widespread disease, unliveable heat, ecosystem collapse, cities menaced by rising seas – these and other devastating climate effects are accelerating and are bound to become painfully obvious before a child born today turns 30.
• Current levels of adaptation will be inadequate to respond to future climate risks. We need transformational change operating on processes and behaviours at all levels: individual, communities, business, institutions and governments. We must redefine our way of life and consumption.
• The worst is yet to come, affecting our children’s and grandchildren’s lives much more than our own. Life on Earth can recover from a drastic climate shift by evolving into new species and creating new ecosystems … humans cannot.