As the UN sits down for its annual climate conference this week, many experts believe we have passed the point of no return.
On Sunday morning hundreds of politicians, government officials and scientists will gather in the grandeur of the International Congress Centre in Katowice, Poland. It will be a familiar experience for many. For 24 years the annual UN climate conference has served up a reliable diet of rhetoric, backroom talks and dramatic last-minute deals aimed at halting global warming.
But this year’s will be a grimmer affair – by far. As recent reports have made clear, the world may no longer be hovering at the edge of destruction but has probably staggered beyond a crucial point of no return. Climate catastrophe is now looking inevitable. We have simply left it too late to hold rising global temperatures to under 1.5C and so prevent a future of drowned coasts, ruined coral reefs, spreading deserts and melted glaciers.
One example was provided last week by a UN report that revealed attempts to ensure fossil fuel emissions peak by 2020 will fail. Indeed the target will not even be reached by 2030. Another, by the World Meteorological Organization, said the past four years had been the warmest on record and warned that global temperatures could easily rise by 3-5C by 2100, well above that sought-after goal of 1.5C. The UK will not be exempt either. The Met Office said summer temperatures could now be 5.4C hotter by 2070.
At the same time, prospects of reaching global deals to halt emissions have been weakened by the spread of rightwing populism. Not much to smile about in Katowice.
Nor will the planet’s woes end in 2100. Although most discussions use the year as a convenient cut-off point for describing Earth’s likely fate, the changes we have already triggered will last well beyond that date, said Svetlana Jevrejeva, at the National Oceanography Centre, Liverpool. She has studied sea-level rises that will be triggered by melting ice sheets and expanding warm seawater in a world 3-5C hotter than it was in pre-industrial times, and concludes these could reach 0.74 to 1.8 metres by 2100. This would be enough to deluge Pacific and Indian Ocean island states and displace millions from Miami, Guangzhou, Mumbai and other low-lying cities. The total cost to the planet could top £11trillion.
Even then the seas will not stop rising, Jevrejeva added. “They will continue to climb for centuries even after greenhouse-gas levels have been stabilised. We could experience the highest-ever global sea-level rise in the history of human civilisation.”
Vast tracts of prime real estate will be destroyed – at a time when land will be needed with unprecedented desperation. Earth’s population stands at seven billion today and is predicted to rise to nine billion by 2050 and settle at over 11 billion by 2100 – when climate change will have wrecked major ecosystems and turned farmlands to dust bowls.