New research suggests that global warming has accelerated in recent years and that the rate of change will continue to accelerate in the short term future. Additionally, the study shows that even if greenhouse gasses are reduced the coming decades could become increasingly uncomfortable before improvements begin to be felt.

Historically people look at rates changes in the Earth’s climate in terms of centuries or even millennia. By contrast, researchers tracking current rates of human caused climate change tend to track changes a year or two at a time, while making predictions about the distant future.

A recent analysis published in the journal Nature Climate Change takes a slight different approach, looking at changes in temperature and climate over 40 year periods to better measure warming trends with an understanding of normal variations and anomalies.

The research suggests that changes are happening faster than historic levels and are beginning to accelerate. The study warns that the planet is now entering a period of change faster than anything that has naturally occurred over the last thousand years.

The study was conducted by interdisciplinary scientist Steve Smith and colleagues at the Department of Energy’s (DOE) Pacific Northwest National Laboratory. The researchers examined both historical and projected changes to accurately determine the trends that will be felt by humans living today.

“We focused on changes over 40-year periods, which is similar to the lifetime of houses and human-built infrastructure such as buildings and roads. In the near term, we’re going to have to adapt to these changes,” said lead author Smith in a statement.

According to the team, the Earth is getting warmer due to greenhouse gasses however the rise is not a continuous line. Temperatures rise and fall and harsh or mild winters, hot and cool summers and other variations are part of the overall trend.

Natural changes in temperature have been studied many times by a wide range of research teams and organizations. However, how temperature will change in timelines relevant to society is less well know. A better grasp of how temperatures will change in the lifetime of the average person could allow individuals and governments to make better decisions.

To conduct their research, the team turned to the Coupled Model Intercomparison Project (CMIP). The CMIP combines two dozen climate models and runs simulations that allow researchers to examine differences between the results of the various models.

All of the CMIP models accessed the same data for past and future greenhouse gasses, pollutant levels and land use models. The team initially looked at temperature ranges between 1850 and 1930, a time from which records are available but the amount of greenhouse gas in the atmosphere was relatively low.

They compared temperature ranges from this period to estimates of prior temperatures calculated using natural sources of information such as coral, ice cores and tree rings for the 2000 years prior to 1850.

The variations seen between 1850 and 1930 were roughly comparable to fluctuations seen over similar periods prior to that time, suggesting that the method was reliable.

During the early periods tested, 40 year variations in North America and Europe rose and fell by as much as 0.2 degrees Celsius per decade.

Next, the team looked at the 40 year period between 1971 and 2020 and found the average rate of change over North America to be about 0.3 degrees of warming per decade. That rate is higher than the natural variability allows. Most regions, globally, were well outside the natural rate of variation according to CMIP.

Finally the team examined the rates going forward would be effected by changes in emissions. They found that climate change continued to accelerate for the next 40 years regardless of future greenhouse gas emissions. However, if emissions remained high then the rate of rapid change continued to accelerate through the end of the century.

“In these climate model simulations, the world is just now starting to enter into a new place, where rates of temperature change are consistently larger than historical values over 40-year time spans. We need to better understand what the effects of this will be and how to prepare for them,” said Smith.