A team of scientists from the University of Exeter, the Met Office and Imperial College has discovered a new way to calculate total carbon emissions in line with Paris' climate target of 1.5.ahC and 2ahC of global warming.
The abnormally warm weather in 2023 almost exceeded 1.5;ahThe C-level Paris target is related to average warming over 10 years. new research Answering the question: How much carbon is left before the Paris limit is exceeded?
About 15 years ago, climate scientists discovered a very useful fact about climate change. Despite the great complexity of the climate system, global warming is overwhelmingly dependent on total carbon dioxide emissions from before the industrial revolution.
converted
This discovery opens up the possibility of defining a total carbon budget consistent with the Paris targets, leading to the definition of net zero as the point at which global warming essentially stops. The problem is that the Earth system models used to make climate projections disagree widely about how much global warming will occur for every billion tons of carbon emissions.
A new study shows that observed global warming and estimated carbon emissions to date are a very good indicator of how much carbon emissions remain until we meet the Paris climate goals. We solve this problem by showing that The authors call this the „emergency constraint.“ This is a fancy name for something very simple.
Basically, they look at results from all available Earth system models. These models form beautiful straight lines connecting each emission. ahC of global warming to date and emissions depending on a certain level of global warming in the future. This means that the best estimates of global warming and emissions to date can be easily converted into estimates of the total carbon budget for the Paris climate goals.
good news and bad news
The good news is that the new study estimates emissions budgets that are at least 10% larger than the model average. The bad news is that if humanity continues to emit carbon dioxide at its current rate, it will take him a little over 10 years to surpass Paris 1.5.ahC target even if it is a 10-year average global warming.
Co-author Chris Jones from the Met Office said: “This new constraint is elegant and powerful. It not only uses observations to narrow the likelihood of future emissions, but also takes into account other greenhouse gases, not just CO.2. In this way, the remaining carbon budget becomes more policy relevant. ”
Peter Cox, lead author and director of the Global Systems Research Institute at the University of Exeter, said: „Our research highlights the climate problems that need to be solved and will stimulate further efforts to reduce emissions to net zero. I look forward to that.“
this author
Brendan Montague is the editor Ecologist. This article is based on the following research Peter Cox, Mark Williamson, Pierre Friedlingstein, Chris Jones, Nina Raoult, Joeri Rogelj, Rebecca Varney, and Urgent constraints on carbon budgets due to global warming impacts2024.