Aaron Putnam sits atop a boulder high in the Sierras of central California, banging away with hammer and chisel to chip out a sample of ice age history. Each hunk of rock is a piece of a vast puzzle: How did our climate system behave the last time it warmed up like it’s doing today?
February 14, 2017
January 22, 2016
As the second most recent ice age was ending and its glaciers began to retreat, the Earth experienced a large, abrupt climate change that shifted the thermal equator southward by about 4 degrees, according to a new study that for the first time tracks that shift in millennial detail, showing how the Northern Hemisphere cooled and the Southern Hemisphere warmed over the span of a few hundred years. The change would have affected the monsoons, today relied on to feed more than half the world’s population, and could have helped tip the climate system over the threshold for deglaciation, said lead author Allison Jacobel.
December 15, 2015
Why does sea level change at different rates? How has it changed in the past? Who will be at risk from more extreme weather and sea level rise in the future? Our scientists often hear questions like these. To help share the answers more widely, we created a new app that lets users explore a series of maps of the planet, from the deepest trenches in the oceans to the ice at the poles. You can see how ice, the oceans, precipitation and temperatures have changed over time and listen as scientists explain what you’re seeing and why.
November 15, 2006
What’s in an isotope? Quite a lot, as it turns out. A new technique developed by researchers at the Lamont-Doherty Earth Observatory now allows scientists to use an isotope of manganese not abundant on Earth to understand the record of millions of years of changes to the Earth’s surface. According to the study's lead scientists, the new technique relies on measuring extremely small amounts of the nuclide that accumulates as cosmic rays strike exposed rock surfaces over long periods of time. This will allow scientists to track processes such as erosion and glaciation that shaped the landscape over millions of years.