Matthew Schmidt, associate professor of oceanography, and Ping Chang, professor of oceanography and atmospheric science and director of the Texas Center for Climate Studies, along with colleagues from Georgia Tech, Princeton, the Woods Hole Oceanographic Institution, the University of Cambridge and Germany’s University of Bremen, have had their findings published in the latest issue of Nature Geoscience.
To make this discovery, the researchers studied the chemistry of shells produced by benthic foraminifera, single-celled organisms that live near the sea floor. These benthic foraminifera were collected from sediment cores recovered from the margins of the Florida Straits. By studying the oxygen isotope composition of the shells, the researchers were able to reconstruct past changes in Florida Current transport, which is directly related to the strength of the global conveyor belt circulation.
Researchers have known for years about Heinrich Events, periods of extreme cold in the North Atlantic. These events were named for the geologist who first discovered them, Hartmut Heinrich. They occurred during the last ice age when immense icebergs broke loose from glaciers, and as they melted, deposited ice rafted debris on the sea floor. Six of these Heinrich events have been identified, and they are known as H1 through H6.
“While there is evidence that the last Heinrich Event that occurred around 17,000 years ago was indeed caused by a dramatic reduction in the ocean’s conveyor belt circulation, our new reconstruction of ocean circulation patterns during some earlier Heinrich Events, that occurred during the last ice age between 20,000 and 30,000 years ago, did not reveal significant changes in ocean circulation,” Schmidt explains. “Nevertheless, these Heinrich Events were experienced worldwide, so they must have been transmitted via the atmosphere.”
Schmidt says that the study “has important implications for our understanding of the mechanisms of abrupt climate change in the past. The more we know about how climate changed in the past, the better prepared we will be for predicting future climate variability.”
Matthew Schmidt | Newswise
04.09.2015 | University of California - Santa Barbara
NASA's Aqua Satellite sees Typhoon Kilo headed west
04.09.2015 | NASA/Goddard Space Flight Center
In a survey of NASA's Hubble Space Telescope images of 2,753 young, blue star clusters in the neighboring Andromeda galaxy (M31), astronomers have found that M31 and our own galaxy have a similar percentage of newborn stars based on mass.
By nailing down what percentage of stars have a particular mass within a cluster, or the Initial Mass Function (IMF), scientists can better interpret the light...
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE have developed a highly compact and efficient inverter for use in uninterruptible power...
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from University of Arizona geoscientists. The study is the first to explain how the steep-fronted plateau formed.
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from...
The leaves of the lotus flower, and other natural surfaces that repel water and dirt, have been the model for many types of engineered liquid-repelling surfaces. As slippery as these surfaces are, however, tiny water droplets still stick to them. Now, Penn State researchers have developed nano/micro-textured, highly slippery surfaces able to outperform these naturally inspired coatings, particularly when the water is a vapor or tiny droplets.
Enhancing the mobility of liquid droplets on rough surfaces could improve condensation heat transfer for power-plant heat exchangers, create more efficient...
Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.
"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...
03.09.2015 | Event News
20.08.2015 | Event News
20.08.2015 | Event News
04.09.2015 | Power and Electrical Engineering
04.09.2015 | Machine Engineering
04.09.2015 | Materials Sciences