Experts at the Potsdam Climate Change Institute have found that compliance with the Paris Agreement to curb the rise in global temperatures at 1.5 degrees Celsius is most likely no longer feasible. The researchers' article was published in the journal Environmental Research Letters, briefly about the scientific work is described in a press release on Phys.org.
Scientists have analyzed 400 climate scenarios assessed by the Intergovernmental Panel on Climate Change (IPCC), with only 50 scenarios avoiding global temperature rises above 1.5 degrees Celsius. It is believed that exceeding this limit will lead to a more chaotic climate and a disastrous situation for millions of people.
It turned out that only 20 scenarios make realistic assumptions about options for mitigating the effects of global warming, including large-scale planting of trees or removing carbon from the Earth's atmosphere. However, all these measures are quite difficult to implement, which makes exceeding the limit almost inevitable.
Only if all levers of climate change mitigation are used can it still be possible to limit global warming to 1.5 degrees Celsius in accordance with the Paris Agreement. For example, humanity must either reduce the demand for electricity or stop using fossil fuels. Land-use should also be restructured to absorb excess carbon in the atmosphere (through re-waterlogging of drained areas or afforestation) and to reduce methane emissions from livestock production. All three of these aspects require a titanic effort at the international level.
Unrealistically optimistic scenarios overestimate the potential for carbon sequestration and storage, or make overly bold assumptions about limiting population growth or a massive shift to a herbivorous diet. In addition, the scientists considered the scenario developed by the oil and gas company Shell, which provides for a reduction in net emissions to zero by 2070, as well as the scenario of the International Energy Agency. Both preclude compliance with the Paris Agreement.
According to scientists, limiting temperature rise to 1.5 degrees Celsius is worth all the efforts as it is about ensuring a safe ecological future for humanity. At the same time, this requires unprecedented measures that, most likely, will never become a reality.