Forests in the south-central United States are some of the country’s most productive and diverse. They also sit in a warming “hole”—an area where the progressive rise in temperature affecting most of the continent hasn’t yet taken hold. A team from Columbia University’s Lamont-Doherty Earth Observatory is studying how these forests might shift—or even disappear—when climate change does catch up with them, as expected.

One foggy spring morning just after a hard rain, Park Williams was tromping through the woods deep in Arkansas’ Ozark Mountains. Toiling down a steep slope, he supposedly was keeping a simultaneous eye out for rattlesnakes, copperheads, poison ivy and big old trees. Williams seemed mostly focused on the trees, though; attention to the other stuff was just slowing him down. Williams studies how forests react to changes in climate, and the Ozarks’ deeply dissected hills and hollers—what some might refer to as typical hillbilly country—are a kind of ground zero for this.

A new international consortium of scientists is bringing the history of temperature fluctuations across the entire Northern Hemisphere to life.

In its first 40 years, the Lamont Tree Ring Lab tracked changing climates around the world, building an international reputation as a global leader in research, training and technology.

Annual tree rings are a rare find in the tropical islands of the eastern Pacific. The new discovery of trees with annual rings on a Hawaiian volcano could provide new climate data from a part of the world where much of the variability of the El Niño-Southern Oscillation originates.