Researchers Find Today’s Rate of Atmospheric Carbon Dioxide Increase 10 Times Faster Than Past 50,000 Years

The rate at which atmospheric carbon dioxide is increasing today is unprecedented, according to a recent study published in the Proceedings of the National Academy of Sciences. Researchers analyzed ancient Antarctic ice cores to gain insight into past climate change periods and better understand the potential impacts of climate change today.

Carbon dioxide, a greenhouse gas, naturally occurs in the atmosphere and contributes to the warming of the climate through the greenhouse effect. While levels of CO2 have fluctuated in the past due to natural causes such as ice age cycles, today’s rise is primarily driven by human emissions.

By studying ice cores collected from Antarctica, scientists were able to identify the fastest rates of natural CO2 rise ever observed. The current rate of increase, largely driven by human activities, is 10 times higher than any previous period in the past 50,000 years.

During the last ice age, there were instances where carbon dioxide levels spiked higher than average, but previous measurements were not detailed enough to fully understand these rapid changes. The recent study focused on these periods and found that jumps in CO2 levels coincided with North Atlantic cold intervals known as Heinrich Events, which are associated with abrupt climate shifts globally.

The researchers discovered that during the largest natural rises in CO2, levels increased by about 14 parts per million in just 55 years. These jumps occurred approximately once every 7,000 years. In contrast, today’s rates would see a similar increase in just 5 to 6 years.

The study also highlighted the impact of strengthening westerly winds on the release of CO2 from the Southern Ocean during past periods of natural carbon dioxide rise. As climate change continues, there is evidence to suggest that these westerlies will strengthen further, potentially reducing the Southern Ocean’s ability to absorb human-generated carbon dioxide.

The findings underscore the importance of understanding past climate change events to better predict and mitigate the impacts of current climate change. By studying ancient ice cores, researchers can piece together a more comprehensive picture of Earth’s climate history and use that knowledge to inform future climate policies and actions.