October 07, 2014Gordon Jacoby Jr., a Columbia University researcher who hiked, flew, dove and paddled into some of the wildest corners on earth in search of trees that could reveal the planet’s workings, died on Oct. 1 at a hospital near his home in Raphine, Va. He was 80.
July 28, 2014
Four years ago this month, archeologists monitoring the excavation of the former World Trade Center site uncovered a ghostly surprise: the bones of an ancient sailing ship. Tree-ring scientists at Columbia University’s Lamont-Doherty Earth Observatory were among those asked to analyze its remains for clues about its age and origins. In a study now out in the journal Tree Ring Research, the scientists say that an old growth forest in the Philadelphia area supplied the white oak used in the ship’s frame, and that the trees were probably cut in 1773 or so—a few years before the bloody war that established America’s independence from Britain.
May 07, 2012
Dendrochronologist Brendan Buckley’s usual occupation is drilling straw-like cores from old trees and extracting information about past climates by studying their rings. To extend the record beyond the time of living trees, he sometimes takes samples from long-dead trees, or even from timbers in ancient buildings. In 2010, the Lamont-Doherty Earth Observatory scientist was part of a team that traveled into the remote Cardamom Mountains of southern Cambodia to investigate human burials contained in coffins carved from entire logs.
November 10, 2011Evergreen trees at the edge of Alaska’s tundra are growing faster, suggesting that at least some forests may be adapting to a rapidly warming climate, says a new study.
July 12, 2011
A team led by Kevin Anchukaitis of the Lamont-Doherty Earth Observatory Tree Ring Lab is currently in Alaska’s Arctic National Wildlife Refuge, studying the effects of changing climate on trees. Ferried in by a bush pilot who landed on the tundra to drop them off, they are practically at treeline–the place where it is too far north for trees to grow. But there are still some spindly white spruces here, and they are taking cores from these, which can be used to measure weather of the past.
May 26, 2011
El Niño and La Niña, the periodic shifts in Pacific Ocean temperatures, affect weather around the globe, and many scientists have speculated that a warming planet will make those fluctuations more volatile, bringing more intense drought or extreme rainfall to various regions.
April 06, 2011
The eruption of the Laki volcano in Iceland in 1783-84 set off a cascade of catastrophe, spewing sulfuric clouds into Europe and eventually around the world.
March 23, 2011
Scientists examining rings from old trees spanning the last 400 years say they show that the U.S. East Coast has suffered droughts longer and more frequent than anything recorded in modern times.
November 03, 2010
Scientists have long known that large volcanic explosions can affect the weather by spewing particles that block solar energy and cool the air. Some suspect that extended “volcanic winters” from gigantic blowups helped kill off dinosaurs and Neanderthals...
September 07, 2010
Expanded irrigation has made it possible to feed the world’s growing billions—and it may also temporarily be counteracting the effects of climate change in some regions, say scientists in a new study. But some major groundwater aquifers, a source of irrigation water, are projected to dry up in coming decades from continuing overuse, and when they do, people may face the double whammy of food shortages and higher temperatures.
May 27, 2010
Some of the worst droughts to hit North Africa in the last 900 years have occurred recently—in the late 20th century—according to an analysis of tree rings that has provided the most lengthy and detailed climate record yet for this sub-tropical region on the Mediterranean.
May 06, 2010
Every day since Jan. 1, 1896, an observer has hiked up a grey outcrop of rock to a spot at The Mohonk Preserve, a resort and nature area some 90 miles north of New York City, to record daily temperature and other conditions there.
April 21, 2010
The seasonal monsoon rains in Asia feed nearly half the world’s population, and when the rains fail to come, people can go hungry, or worse. A new study of tree rings provides the most detailed record yet of at least four epic droughts that have shaken Asia over the last thousand years..
March 29, 2010
Decades of drought, interspersed with intense monsoon rains, may have helped bring about the fall of Cambodia’s ancient Khmer civilization at Angkor nearly 600 years ago, according to an analysis of tree rings, archeological remains and other evidence.
September 30, 2009
A 2005-2007 dry spell in the southeastern United States destroyed billions of dollars of crops, drained municipal reservoirs and sparked legal wars among a half-dozen states—but the havoc came not from exceptional dryness but booming population and bad planning, says a new study.
January 06, 2009
But Global Warming May Have Helped Override Some Recent Eruptions
Climate researchers have shown that big volcanic eruptions over the past 450 years have temporarily cooled weather in the tropics—but suggest that such effects may have been masked in the 20th century by rising global temperatures
October 07, 2004
Researchers from the Lamont-Doherty Earth Observatory of The Earth Institute at Columbia University have used 835 annual tree-ring chronologies based on measurements from 20- to 30-thousand tree samples across the United States, Mexico, and parts of Canada to reconstruct a history of drought over the last 2005 years. The resulting drought reconstructions have been organized into a North American Drought Atlas CD-ROM, the first of its kind, which maps year-by-year occurrences of droughts.
|Park Williams Discovers History and Science in a Tree Ring|
|The Páramos||Climate change threatens a fragile ecosystem in the Andes|
|Ancient Trees Reveal Environmental Histories||Part of the 2011 Public Lecture Series|
|Tree Rings, Climate Change and the Rainy Season|
|A Natural History of the Palisades||Public Lecture, 2005|