TUCSON, Ariz. — According to 24,000 years worth of climate data, a new study finds global temperatures have increased at an “unprecedented” rate over the last two centuries.
Researchers from the University of Arizona mapped out the temperature of the Earth for each 200-year interval since the last Ice Age and confirmed the world is rapidly warming. The study verified that Earth has generally warmed over the last 10,000 years, settling a decade long debate about whether this period trended warmer or cooler among experts.
Greenhouse gas concentrations and the retreat of the ice sheets are to blame as the main drivers of climate change, the study reveals. The team combined two independent data sets – temperate data from marine sediments and computer simulations of climate.
“This reconstruction suggests that current temperatures are unprecedented in 24,000 years, and also suggests that the speed of human-caused global warming is faster than anything we’ve seen in that same time,” says Dr. Jessica Tierney in a university release.
How do scientists forecast the past?
“To forecast the weather, meteorologists start with a model that reflects current weather, then add in observations such as temperature, pressure, humidity, wind direction and so on to create an updated forecast,” Tierney explains.
“We’re excited to apply this approach to ancient climates that were warmer than today,” the study author continues.
“With this method, we are able to leverage the relative merits of each of these unique datasets to generate observationally constrained, dynamically consistent and spatially complete reconstructions of past climate change,” postdoctoral researcher Matthew Osman adds.
Now, the team is working on using their method to investigate climate change going back even further into the past. The team created maps of global temperature changes for every 200-year interval going back 24,000 years.
“The fact that we’re today so far out of bounds of what we might consider normal is cause for alarm and should be surprising to everybody,” Dr. Osman says.
“These maps are really powerful,” the researchers concludes. “With them, it’s possible for anyone to explore how temperatures have changed across Earth, on a very personal level. For me, being able to visualize the 24,000-year evolution of temperatures at the exact location I’m sitting today, or where I grew up, really helped ingrain a sense of just how severe climate change is today.”
The study is published in the journal Nature.
South West News Service writer Joe Morgan contributed to this report.