Large climate uncertainty even with 1.5 degree temperature increase
The Paris climate agreement includes the aim of limiting average global warming to 1.5°C. There has previously been little research on how climate might look across the world and over time with this level of temperature increase, phys.org wrote.
Climate scientists have now shown that even this lower level of warming could lead to very different consequences on a regional level.
Since the Paris Agreement in 2015, two numbers have been floating around: Two and 1.5.
At the climate conference, the nations agreed that average global warming should be limited to well below 2°C, and that efforts should be pursued to limit it to 1.5°C.
This may look at first glance like pedantic haggling over a few unimportant tenths of a degree, but it could be of paramount importance for the global climate and humanity.
This has been shown by a study conducted by an international research group and recently published in the journal Nature.
It appeared in connection with a special report from the Intergovernmental Panel on Climate Change (IPCC) about 1.5°C global warming, scheduled to be published this autumn.
One of the lead authors of the special report is ETH Professor Sonia Seneviratne.
She said, “A lot has been researched and written about the 2°C goal, but not about the 1.5°C goal.”
Avoiding extreme deviations
In their new study, the climate scientists show that limiting global warming to 1.5°C would avoid risks of extreme deviations from today’s climate that could appear if it increased to 2°C.
Dramatic cut in CO emissions
However, these options to mitigate climate change could be risky, because CCS is not yet well established and the production of bioenergy requires large areas of land, which could cause competition with food production.
Seneviratne said, “Such problems could be better avoided by drastically and quickly reducing CO2 emissions.”
This could also be achieved with increased energy efficiency, lower energy use, additional use of renewable energies and a global reduction in meat consumption.
There are various estimated of how much CO2 can be emitted without missing the 1.5°C goal; none of them offers much leeway.
She added, “It’s clear that we must urgently reduce emissions if we want to stand a chance of meeting the 1.5°C goal and keeping any temperature overshoot as low as possible.”
It is therefore necessary to quickly research and implement solutions to combat climate change, she said, even if only in test projects and on small scale: “As an innovative country, Switzerland can contribute significantly to this effort.”