In the Aug. 13 issue of the journal Nature, climate researchers including Jonathan Woodruff of the University of Massachusetts Amherst show that the frequency of intense hurricanes in the Atlantic Ocean over the last 1,500 years has been closely linked to long-term changes in the El Niño/Southern Oscillation (ENSO) and sea surface temperature. The finding could help with hurricane modeling and prediction in the future.
Establishing the link between hurricane variability and climate change over these longer timescales “is a new viewpoint for us,” Woodruff explains. “There’s a randomness to hurricanes. But the fact that we can see trends that rise above that randomness is significant and a bit of a surprise. Our work indicates that hurricane activity has responded noticeably to past climate shifts. When considering future climate change over the next century, our results indicate that measurable changes in hurricane activity could occur, rising above the noise in the system.”
A relationship between ENSO, sea surface temperature and hurricane activity is seen in modern times, Woodruff says, but the historical record based on ships’ logs and other observations is not long enough to assess variability on timescales longer than a few decades at best. “Given the possible effects of continued climate warming on intense tropical cyclone activity, it’s essential that we develop an understanding of how past climate change has affected tropical cyclone frequency, intensity and track on longer timescales,” the geologist says. “This work is another step forward in understanding the complex relationship between climate variability and Atlantic hurricane activity.”
Woodruff and colleagues’ study shows that a statistical climate model and actual paleoclimate data cross-validate each other over the last 1,500 years during key intervals of climatic change.
Specifically, UMass Amherst’s Woodruff and colleagues at Penn State and Woods Hole Oceanographic Institute prepared sedimentary reconstructions of hurricane-induced flooding, preserved in coastal ponds and salt marshes and collected as core samples from eight representative sites throughout the western North Atlantic, an approach known as paleotempestology.
These environments are usually protected from the sea by barrier beach systems. They enjoy sustained quiet periods during which only fine-grained mud and organic materials build up on pond floors and marsh surfaces. But during hurricanes and other storms, these normally calm environments are overrun with ocean waves and storm surges that carry in coarser sand from the barrier beaches. The sedimentary record is thus one of fine-grained organic mud, interbedded with coarse-grained, storm-induced deposits. Such deposits serve as natural archives of past hurricanes, with storm reconstructions that can extend back for many thousands of years, Woodruff points out.
Although still limited to a few reconstructions at present, he and colleagues have now observed statistically significant trends in tropical cyclone activity emerging from paleo-hurricane records. They compared these trends to data from a statistical model which independently predicted hurricane variability using paleo-reconstructions of climate factors known to influence hurricane activity, such as sea surface temperature, ENSO and the North Atlantic Oscillation.
The model predicted similar trends to those observed in the paleo-storm reconstructions, with an observed decrease in hurricane activity during the “Little Ice Age” around 300 years ago, a time when sea surface temperatures were lower than today and El Niño events appear to have occurred more frequently. Likewise, a period of increased hurricane activity similar to present levels also occurred around 1,000 years ago during an interval known as the “Medieval Climate Anomaly,” driven predominantly by increases in both sea surface temperature and the frequency of La Niña events.
Woodruff says the new finding “is like so much in science―in hindsight it makes sense. When the evidence is supplied, it’s simple enough to see the relationships, as in this case with the two independent records telling the same story. But until we had this evidence, things were much less clear.”
Jon Woodruff | Newswise Science News
Further reports about: > Atlantic > Atlantic hurricane activity > Climate change > ENSO > El Niño > Hurricanes > Nature Immunology > Woods Hole Oceanographic > fine-grained organic mud > future climate change > hurricane activity > organic material > oscillation > paleotempestology > sea surface > sea surface temperature > storm-induced deposits > tropical cyclone > tropical cyclone activity
UCI and NASA document accelerated glacier melting in West Antarctica
26.10.2016 | University of California - Irvine
Ice shelf vibrations cause unusual waves in Antarctic atmosphere
25.10.2016 | American Geophysical Union
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
26.10.2016 | Power and Electrical Engineering
26.10.2016 | Awards Funding
26.10.2016 | Power and Electrical Engineering