PENNSYLVANIA, USA — Scientists say 2021 was the Earth's sixth-hottest year on record, a ranking that symbolizes just a small part of a long-term warming trend that is set to accelerate.
“The last eight years now have been the hottest on record," said Michelle Thaller, a scientist at NASA's Goddard Space Flight Center. "So, even though it  wasn’t number one, it still falls into the eight hottest years on record...so it does count for us as an addition to the upper trend of temperatures across the globe.”
What’s even more concerning is that the planet is currently in the middle of a La Niña oscillation, which is a natural cooling of parts of the Pacific ocean that brings chilled, deep ocean water to the surface. Therefore, temperatures are supposed to be cooler than they are due to the cooling oscillation process.
However, Thaller noted fossil fuel emissions directly contribute to both the extreme hot and cold temperatures the earth is seeing.
“What you can do again is look at the long-term trends," she said. "It's easy to think of temperatures rising just meaning that things get hotter. It also means that there’s more energy in the atmosphere, more energy for clouds to move around, for circulation patterns to change. So you are actually looking at extremes on both ends.”
In 2021, extreme temperatures obliterated many North American cities' summer heat records, ultimately causing devastating wildfires. Europe also experienced its hottest summer on record last year, with high temperatures bringing heatwaves in the south and floods in the north.
Experts continue to emphasize that these events are a bleak reminder of the need to support and participate in climate action. Otherwise, humans will bear the brunt of both subtle and not-so-subtle repercussions.
“Of course, if you’re the one dealing with a hurricane, that’s something that’s right in front of you," said Thaller. "Things like ocean level rise are lower, that’s something that is not happening every day of your life but over the next decades. That could change where people live, it could even change agriculture.”