Scientists have determined that in the beginning of 2029, the Earth is expected to surpass a crucial threshold for warming.


According to a recent study, in approximately five and a half years from now, potentially by early 2029, the world may no longer be able to maintain the agreed upon global warming temperature limit if it continues to consume fossil fuels at its current pace.

The research brings us three years closer to the anticipated point when the planet will reach a crucial climate tipping point, marked by a rise of 1.5 degrees Celsius (2.7 degrees Fahrenheit) since the 1800s.

As the temperature rises, the likelihood of catastrophic events also increases. This could result in the loss of a significant amount of coral reefs and potentially trigger irreversible melting of a crucial ice sheet. Additionally, there may be a rise in water scarcity, heat waves, and fatalities due to extreme weather conditions, as stated in a previous scientific report by the United Nations.

Rephrasing: Reaching the threshold will occur earlier than originally projected due to global efforts in reducing a distinct form of air pollution known as aerosols. According to the main researcher of the study, aerosols have a slight cooling effect on the planet and conceal the impact of burning fossil fuels. In other words, while reducing aerosol pollution is beneficial, it also results in slightly faster temperature increases.

The research published in the journal Nature Climate Change on Monday determines the remaining “carbon budget,” or the amount of fossil fuels that can be consumed while still having a 50% chance of keeping warming below 1.5 degrees Celsius since the start of the industrial era. This aligns with the goal established by the 2015 Paris agreement.

In the past decade, the average temperature has increased by 1.14 degrees Celsius (2.05 degrees Fahrenheit) compared to the 19th century. The previous year saw a rise of 1.26 degrees Celsius (2.27 degrees Fahrenheit) and this year is expected to surpass that, according to experts.

The recent research established the carbon limit to be 250 billion metric tons. Currently, the world is emitting just over 40 billion metric tons per year, with an increasing trend. This leaves only six years until the limit is reached. However, according to the study, the countdown began in January 2023, meaning that there are now only five years and a few months remaining.

According to Robin Lamboll, a climate scientist at Imperial College London, if we are not on a significant downward trend within the next six years, it may be too late to successfully combat climate change and achieve the 1.5 degree limit.

The 2021 report from the United Nations’ Intergovernmental Panel on Climate Change stated that a budget of 500 billion metric tons was needed to limit the global temperature increase to 1.5 degrees by mid 2032, according to Lamboll. In June, an update from several IPCC authors confirmed Lamboll’s team’s carbon budget, with IPCC co-chair and climate scientist Valerie Masson-Delmotte noting the more thorough analysis done by Lamboll.

The most significant difference between the 2021 report and this year’s studies is the discovery of larger decreases in aerosol emissions. These emissions come from sources such as wildfires, sea salt spray, volcanoes, and burning fossil fuels, and contribute to the creation of sooty air that has a slight cooling effect on the planet, masking the stronger impact of greenhouse gases. As we work towards reducing carbon emissions, we are also unintentionally reducing cooling aerosols. This has been taken into consideration in the study, along with updates to computer simulations, according to Lamboll.

The depletion of the carbon budget by 2029 does not guarantee an immediate rise of 1.5 degrees above pre-industrial levels. According to Lamboll, the temperature increase may occur slightly earlier or up to a decade or two later, but will inevitably happen when the budget is exhausted.

The authors caution against the misconception that reaching the budget limit of 1.5 degrees is the only opportunity to prevent further global warming. According to their research, the carbon budget that gives a 50% likelihood of limiting warming to 2 degrees Celsius (3.6 degrees Fahrenheit) is 1220 billion metric tons, which equates to approximately 30 years.

“We do not want this to be perceived as having six years to rescue the planet,” stated Christopher Smith, co-author of the study and a climate scientist from the University of Leeds. “Even if we are able to restrict the warming to 1.6, 1.65, or 1.7 degrees, it is still significantly better than reaching 2 degrees. We must continue to strive for every fraction of a degree.”

According to Bill Hare, a climate scientist at Climate Action Tracker, surpassing the 1.5 degree limit is not an immediate disaster, but it marks a critical point where the likelihood of severe and irreversible consequences greatly increases.

As global leaders prepare for climate talks in Dubai next month, they remain confident in achieving the 1.5-degree limit. Lamboll explains that while it is technically feasible to limit warming to 1.5 degrees, it presents significant political obstacles and is unlikely to be achieved.

According to climate scientist Glen Peters from the Norwegian CICERO climate institute, the 1.5C carbon budget has become so small that it is almost meaningless. He was not involved in the research. Peters compares the situation to having your face about to hit a wall at 100 miles per hour – whether your nose is 1 millimeter or 2 millimeters away from the wall doesn’t matter. The important thing is that we are still going in the wrong direction at high speed.

Climate scientist Piers Forster from the University of Leeds, who was not involved in Lamboll’s team, advises individuals to take action instead of worrying. According to Forster, taking swift action can potentially reduce the rate of global warming by half in the next decade.

___

Find more articles about climate and the environment from AP at http://www.apnews.com/climate-and-environment.

___

Follow Seth Borenstein on X, formerly known as Twitter at @borenbears

___

The Associated Press’s climate and environmental reporting is funded by numerous private foundations. Learn more about AP’s efforts in covering climate change here. The AP bears full responsibility for all published material.

Source: wral.com