Global temperatures have a 48 per cent chance of reaching 1.5 degrees above pre-industrial levels at least once within the next five years, according to new findings from the World Meteorological Organization (WMO). The 1.5-degree Celsius threshold is the lower limit of warming agreed in the Paris Agreement and exceeding this long-term will lead to potentially irreversible damage, such as rising sea levels, and both the warming and acidification of oceans.
Surpassing the threshold in just a single year does not violate what was agreed in Paris, but it shows that the earth is perilously close to exceeding this global average temperature on a long-term basis, according to scientists at the United Nations agency. "When we reach 1.5 degrees, it doesn't mean that the Paris Agreement is over. It just means that it's a clear signal that efforts really need to be redoubled to reach what we call net-zero or a carbon-neutral economy," Maxx Dilley, WMO's Deputy Director for Climate told DW .
Dilley said that if the world acts the temperature will come down, although not overnight, urging people not to lose hope. "It doesn't mean that if the temperature is 1.5 degrees up for a year that we should give up. On the contrary, it means that more urgent efforts are needed to keep the temperature increase rate from rising and also to try to try to bend the curve back downwards again."
Rapidly warming planet
While WMO scientists said that any surge over 1.5 degrees Celsius may be temporary, there is a clear trend towards rising temperature. In the five years from 2015, the chances of temperatures breaching 1.5 degrees Celsius of warming in a single year was close to zero compared to one-in-two today. And now, there is a 93 per cent chance that at least one of the years between 2022 and 2026 will be the warmest on record — surpassing the 2016 high, which was exacerbated by the El Nino climate pattern. The average temperature over those entire five years is also 93 per cent more likely to be higher than the previous five years.
From 2022 to 2026, the annual mean global near-surface temperature is forecast to be between 1.1 degrees and 1.7 degrees higher than pre-industrial levels. These new figures were reported in the Global Annual to Decadal Climate Update, which combines highly accurate climate forecasts from around the world. "I've been involved in climate forecasting now for 25 years. I've never seen skill levels, anything like what we have in terms of the ability of these models to accurately predict global average annual temperature," WMO's Dilley said.
What does this mean for the world?
The global temperature has already risen by about 1.1 degrees Celsius since the industrial revolution. And even with warming limited to 1.5 degrees warming, scientists are predicting dire consequences. Extreme weather patterns, including deadly heat waves and storms, will be far more frequent, droughts become more common, water becomes scarcer, species will die off as biomes change and biodiversity suffers, and the risk of chain-reaction-like emission events increases with the melting of permafrost and the reduction of forests. "We're seeing already glimpses of what a climate change world is going to look like. And I hope that is a wake-up call for everyone, policymakers and the public alike, that we need to do something," Dilley said.
But exceeding 1.5 degrees will lead to even more drastic consequences, such as the disappearance of low-lying countries like many Pacific islands and parts of Bangladesh. Extreme weather patterns become substantially worse at 2 degrees. According to the Intergovernmental Panel on Climate Change, there is an increasingly small window to limit warming to 1.5 degrees, with scientists calling for significant emission reductions this decade.
The IPCC report found that warming cannot be limited to 1.5 degrees unless emissions peak by 2025 and there are net-zero CO2 emissions globally by the early 2050s. To achieve this, rapid change across sectors will be required, with a particular urgency for an exit from fossil fuels and a transition to renewable energy. Under current pledges — which largely exist only on paper — global warming will exceed 2 degrees.