Global Warming Safe Threshold to Be Surpassed in 6 Years

The latest research indicates that worldwide carbon emissions are on a dangerous path, and the threshold for global warming is likely to surpass safe limits by 2030. This could trigger severe consequences related to climate change. To steer away from this perilous course, we must act within the next six years to significantly cut down on greenhouse gas emissions.

An assessment of carbon allowance

A fresh assessment of our remaining carbon allowance—)the maximum amount of carbon dioxide we can release without pushing global temperatures past a hazardous point—reveals that starting from January, if we emit more than 276 gigatons (equivalent to 250 metric gigatons) of CO2, we risk raising temperatures by 1.5 degrees Celsius (equal to 2.7 degrees Fahrenheit) above preindustrial levels.

The study’s findings suggest that if emissions persist at the current pace, we will surpass this critical threshold before the decade’s end. These findings were reported in a study published on Monday, October 30th in the journal Nature Climate Change.

Robin Lamboll, the lead author of the study and a researcher at the Center for Environmental Policy at Imperial College London, emphasizes, “Our finding confirms what we already know—we’re not doing nearly enough to keep warming below 1.5 degrees C.”

He further said, “We can be ever more certain that the window for keeping warming to safe levels is rapidly closing.”

Leaders came together to endorse the Paris Agreement

Back in 2015, 196 leaders from around the world came together to endorse the Paris Agreement, which is a legally binding treaty concerning climate change.

The primary goal of this agreement is to ensure that the global average temperature doesn’t increase by more than two degrees Celsius (equivalent to 3.6 degrees Fahrenheit) above the levels seen in the preindustrial era.

The agreement strongly emphasized that by limiting global warming to just 1.5 degrees Celsius, we could significantly reduce the most severe consequences of climate change.

Intermittent periods of increase in temperature due to global warming

Earlier this year, a report from the United Nations cautioned that we might soon experience intermittent periods during which temperatures exceed the critical 1.5 degrees Celsius mark. However, the recent study focuses on the longer-term trend of increasing temperatures.

Currently, people release nearly forty gigatons of CO2 into the air each year, as stated. Unless we make substantial cuts in these emissions, we will use up our remaining carbon allowance to stay under the 1.5-degree Celsius limit in the next six years.

Benjamin Sanderson, the research director at the Center for International Climate and Environmental Research in Norway, who was not part of the study, pointed out, “This does not mean that 1.5 degrees C will be achieved on that timescale.”

He explained in an article for Nature News & Views that there’s a delay between emitting carbon and feeling the warming effects. This means that the unusually high temperatures we’ve experienced in recent months and years are mainly a result of emissions from the past.

Report by Intergovernmental panel on global warming

The new study relies on information from a recent report by the Intergovernmental Panel on Climate Change. However, Lamboll and his team made adjustments to the methods to consider the most recent emissions and also took into account past aerosol emissions.

In order to limit global warming to 1.5 degrees Celsius – a threshold the Intergovernmental Panel for Climate Change (IPCC) suggests is safe – carbon neutrality by mid-21st century is essential.✊✊ pic.twitter.com/y4ckudTrNr

— NETZERO (@Nzero_official) January 9, 2023

Aerosols are tiny particles that float in the atmosphere, and they have the ability to reflect sunlight, which can have a cooling effect on the climate. This cooling effect partially counteracts the warming caused by greenhouse gases.

The updated calculation reduces the remaining carbon allowance to keep global warming under 1.5 degrees Celsius from 550 gigatons (equivalent to 500 metric gigatons) of CO2 to just 276 gigatons.

The research team also determined that we have around 1,323 gigatons (about 1,200 metric gigatons) of CO2 left that we can emit before we exceed the primary limit set by the Paris Agreement, which is two degrees Celsius.

However, this larger budget will be used up within the next two decades if we don’t take action to promptly begin decreasing emissions.

Uncertainties in the estimations

The estimations carry considerable uncertainties, particularly related to the impact of other greenhouse gases, such as methane. Additionally, it remains unclear how different aspects of the climate system will respond as temperatures continue to rise.

For example, certain regions might experience increased plant growth, which could absorb a significant amount of CO2 and offset some of the warming. On the other hand, changes in ocean currents and the melting of ice sheets might accelerate the warming process.

These uncertainties underscore the urgent need to reduce emissions, as emphasized by Lamboll swiftly. He mentioned, “The remaining budget is now so small that minor changes in our understanding of the world can result in large proportional changes to the budget.”

He further said, “Every fraction of a degree of warming will make life harder for people and ecosystems.”