The recent report on carbon emissions threatening the 1.5C climate threshold has raised concerns about the urgency of taking radical action to mitigate the impact of global warming. According to the researchers, the 1.5C limit could be breached as early as 2029, much sooner than previously anticipated.
The report highlights that record carbon dioxide emissions over the past three years are a significant contributing factor. It also emphasizes the need for a better understanding of how fossil fuel burning affects the atmosphere. The year 2023 is expected to experience temperatures close to 1.5C above the pre-industrial level. Scientists worry that if greenhouse gas emissions continue at the current rate, this level of warming may persist for much longer.
Rising levels of carbon dioxide and other gases in the atmosphere trap the earth’s radiation and create a greenhouse effect, leading to temperature increases. The 1.5C figure is crucial as it forms a cornerstone of the commitments made by political leaders in the Paris climate agreement. The agreement aimed to limit global temperature rise to “well below” 2C and make efforts to keep it below 1.5C.
Developing states and small island nations, in particular, view the 1.5C threshold as essential due to concerns about rising sea levels. Going beyond this level of warming would pose significant threats to their homes and territories. To determine how long it will take to reach this critical figure, scientists calculated a “budget” of the remaining carbon emissions that can be released before breaching the 1.5C threshold.
The Intergovernmental Panel on Climate Change (IPCC) projected earlier this year that the world could emit another 500 billion tons of carbon to have a 50% chance of staying below the 1.5C limit. However, the recent analysis suggests that the threshold will likely be crossed much sooner than previously estimated. The researchers adjusted the budget downward to account for carbon emissions from the past three years, which were not included in the IPCC’s calculations.
The study also reevaluated the impact of sooty particles called aerosols, which arise from burning fossil fuels. While aerosols contribute to air pollution, they have a cooling effect on the climate by reflecting sunlight back into space. However, as efforts to reduce air pollution and fossil fuel usage increase, the number of aerosols in the atmosphere declines, causing temperatures to rise faster than previously thought.
Based on these findings, the researchers claim that only about six years’ worth of current emissions can be released before exceeding the 1.5C reference point set by the Paris agreement. This means that global carbon dioxide emissions would have to reach net zero by 2034, much earlier than the current 2050 target.
The report emphasizes the need for more radical action on emissions to prevent surpassing the 1.5C threshold. It argues that achieving a 50% or higher likelihood of limiting global warming to 1.5C seems virtually impossible based on the currently available socio-technical scenarios described in scientific literature.
With the upcoming COP28 in Dubai, this analysis presents global leaders with a stark outlook on the urgency of taking more decisive action on emissions. The meeting will be crucial in determining whether political slogans to “keep 1.5C alive” can be translated into tangible measures to combat climate change.
Prominent experts in the field stress the importance of cutting carbon emissions as quickly as possible. They emphasize that even if the average temperature rise exceeds 1.5 degrees, any saved emissions can help mitigate the damage. Therefore, every ton of carbon dioxide saved becomes increasingly significant given the limited remaining carbon budget.
