Climate, what Earth will look like with a rise of “just” 1.5 degrees
Environment — di Maurizio Bongioanni
Governments say they will strive to keep the temperature rise within 1.5 degrees Celsius. Either way, the world is set to change.
Climate, what Earth will look like with a rise of “just” 1.5 degrees
Governments say they will strive to keep the temperature rise within 1.5 degrees Celsius. Either way, the world is set to change.
The Paris Agreement aims to curb global warming, keeping the rise in average global temperature well below 2 degrees Celsius. One of the worst consequences is the melting of ice, which will inevitably lead to a rise in sea levels.
Even if the implications are not immediately visible in concrete terms, in the text approved during Cop 21 states agreed to "pursue efforts" to limit the rise in global temperature to 1.5 degrees Celsius above pre-industrial levels.
What will the world look like with 1.5 degrees more?
The first to ask was Richard Betts, a climate impacts expert at the University of Exeter. Betts drew on data from the Met Office, the UK's national meteorological service, which show a rise of 1.2 degrees over the course of 2016 compared with the years 1850–1900: "We could reach 1.5 degrees more as early as the end of 2020, but probably later. Either way, in the first year we won't notice the difference."
When we reach 1.5 degrees more, heatwaves and floods will become defining features of the climate. According to Betts, some effects, such as rising sea levels or the extinction of animal species, will manifest with a delay relative to climate change, simply because these processes take longer. "None of this should lull us into a false sense of security, though. While rising sea levels or biodiversity loss may not be apparent in the first year above 1.5 degrees, some of these processes will already be inevitable."
Reducing CO2 is not enough
There is an enormous debate as to whether it is possible to limit the temperature rise to 1.5 degrees. Either way, even this limit entails consequences: according to Betts, it is not enough to stop releasing CO2 into the atmosphere — it is necessary to remove what is already in excess.
"When temperatures have risen by 1.5°C we won't be able to look at the climate in the first year and think we can relax and let the warming continue." Betts insists on reminding us that in the first year we will not witness the full impact. "We don't know the effects of low-level warming over a longer period." Action is needed. And it must come soon.
