Redefining ‘net zero’ won’t stop global warming

Nov. 18 () –

Trust ‘natural carbon sinks’ such as forests and oceans to offset current CO2 emissions from the use of fossil fuels will not really stop global warming.

This is the opinion of a study led by Oxford physicists and that includes the international group of authors who developed the science of ‘net zero emissions’, which does not include these natural carbon sinks in the definition of net human-induced CO2 emissions.

Natural sinks play a vital role in moderating the impact of current emissions and reducing atmospheric CO2 concentrations after the net zero date, stabilizing global temperatures. However, governments and corporations are increasingly turning to them to offset emissions, rather than reducing fossil fuel use or developing more permanent CO2 removal options.

Emissions accounting rules encourage this by creating an apparent equivalence between fossil fuel emissions and CO2 reductions by some natural carbon sinks, meaning a country could appear to have “achieved net zero” while still contributing. to current warming.

The authors, who publish their conclusions in Nature, Call on governments and companies to clarify the extent to which they rely on natural carbon sinks to meet their climate goals, as well as to recognize the need to achieve a ‘zero geological dent’.

The geological net zero level implies balance carbon flows in and out of solid Earthwith one ton of CO2 committed to geological storage for every ton that continues to be generated with the continued use of fossil fuels. Given the costs and challenges of permanent geological storage of CO2, achieving net geological zero will require a substantial reduction in the use of fossil fuels.

IT CANNOT COMPENSATE THE CONTINUOUS USE OF FOSSIL FUELS

The authors stress the importance of protecting and maintaining natural carbon sinks, although they accept that doing so cannot compensate for the continued use of fossil fuels. Total historical CO2 emissions determine the extent to which a country or company has contributed to the global need for natural carbon sinks.

A country like the UK, with historically large emissions and limited natural sinks, has implicitly committed other countries to maintaining natural sinks for decades after the UK’s emissions reach net zero. This is not currently addressed in climate talks.

Professor Myles Allen, from the Department of Physics at the University of Oxford, who led the study, summarizes in a statement: “We are already counting on forests and oceans to absorb our past emissions, most of which came from burning material we dug out of the ground. We can’t expect them to also offset future emissions. By mid-century, all the carbon that continues to come out of the ground will have to be permanently stored again. That is the Geological Net Zero.