Navigation Links
A cooler Pacific may have severely affected medieval Europe, North America
Date:6/9/2010

MIAMI June 9, 2010 -- In the time before Columbus sailed the ocean blue, a cooler central Pacific Ocean has been connected with drought conditions in Europe and North America that may be responsible for famines and the disappearance of cliff dwelling people in the American West.

A new study from the University of Miami (UM) has found a connection between La Nia-like sea surface temperatures in the central Pacific and droughts in western Europe and in what later became the southwestern United States and Mexico, as published in a recent issue of Geophysical Research Letters.

"We've known for some time the connection between El Nio and La Nia and the weather conditions in North America and Europe," said Robert Burgman, a climate scientist at UM's Rosenstiel School of Marine & Atmospheric Science. "La Nia-like conditions, such as those we found, can cause persistent drought, and as we know warm conditions cause increased precipitation."

Using cores of fossil coral from the Palmyra Atoll in the central Pacific Ocean, Burgman and a team used reconstructed sea surface temperatures from the period 1320 to 1462 to simulate medieval climate conditions with a state-of-the-art climate model. When the differences between medieval and modern climate simulations were compared with paleo-records like tree-rings and sediment cores from around the globe, the authors found remarkable agreement.

During the 142-year study period, the sea surface temperature dropped only one-tenth of one degree, but it was enough to cause arid conditions in North America and Europe.

The Anastazi peoplewho lived in dramatic cliff dwellings near what later became known as the "Four Corners" area at the intersection of the state of Utah, Colorado, New Mexico, and Arizonaleft their settlements at Mesa Verde and other locations some 600 years ago without explanation. A prolonged drought is thought to be one of the contributing factors to their departure.

In Europe, the study period was preceded by three years of torrential rains, which led to the Great Famine from 1315 to 1320, and marked the transition from the Medieval Warm Period to the Little Ice Age, which began in the mid 1500s. During that time, extreme weather conditions were thought to be responsible for continued localized crop failures and famines throughout Europe during the remainder of the 14th Century.

"The marriage of complex climate models with paleo-records of sea surface temperature and other climate variables provide valuable insight to climate scientists who wish to understand climate variability and change before the instrumental record," said Burgman.

Warning that the Palmyra Atoll data only represents one data point, Burgman emphasized that he would like to test his thesis with data from other oceans. "If we can fill in the gaps with data from corals and other records from the Atlantic, Pacific, and Indian oceans, we'll have a better idea of what has happened to the global climate over time," he added.

In the study, Burgman and his colleagues used the reconstructed tropical Pacific sea surface temperatures to create a 16-member ensemble of atmospheric general circulation model (ACGM) simulations, coupled with a one-layer ocean model outside of the tropical Pacific. When the ACGM simulations were compared with the modern climate simulations, they were able to reproduce many aspects of the medieval climate found in observational records for much of the Western Hemisphere, northern Eurasia, and the northern tropics. These results suggest that many features of global medieval hydroclimate changes can be explained by tropical Pacific sea surface temperatures.


'/>"/>

Contact: Barbra Gonzalez
barbgo@rsmas.miami.edu
305-421-4704
University of Miami Rosenstiel School of Marine & Atmospheric Science
Source:Eurekalert

Related biology news :

1. Giant grass offers clues to growing corn in cooler climes, researchers report
2. Register now for the IOF Regionals -- 1st Asia-Pacific Osteoporosis Meeting
3. New marine plant identification guide for Panamas Eastern Pacific
4. Pacific Biomarkers, Inc. Schedules Second Quarter Conference Call for Friday, February 12, 2010
5. New Fujitsu UHF RFID Technology Implemented at Fairmont Pacific Rim Hotel for Advanced Inventory Monitoring
6. Managing Pacific Northwest dams for a changing climate
7. Pacific Biometrics, Inc. Announces the Appointment of Michael Murphy, PhD as Chief Operating Officer
8. Pacific Biometrics, Inc. Stockholders Approve Company Name Change to Pacific Biomarkers, Inc.
9. Announcing IOF Regionals 1st Asia-Pacific osteoporosis meeting
10. Pacific Biometrics Inc. Reports First Quarter Operating Results
11. Tags reveal white sharks have neighborhoods in the north Pacific, say Stanford researchers
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/9/2016)... AWRE ), a leading supplier of biometrics software and services, ... December 31, 2015.  --> --> ... an increase of 61% compared to $4.3 million in the same ... was $2.6 million compared to $0.2 million in the fourth quarter ... Higher revenue and operating income in the fourth quarter of this ...
(Date:2/5/2016)... Feb. 5, 2016 ... the "Global Facial Recognition Market 2016-2020" ... http://www.researchandmarkets.com/research/5kvw8m/global_facial ) has announced the addition ... 2016-2020" report to their offering. ... ) has announced the addition of the ...
(Date:2/3/2016)... , February 3, 2016 ... new market research report "Automated Fingerprint Identification System Market ... Latent Search), Application (Banking & Finance, Government, Healthcare, and ... by MarketsandMarkets, the market is expected to be worth ... of 21.0% between 2015 and 2020. The transformation and ...
Breaking Biology News(10 mins):
(Date:2/10/2016)... , Febr. 10, 2016 /PRNewswire/ - BioAmber Inc. (NYSE: ... to announce that Mitsui & Co. Ltd., its partner ... acid plant, is investing an additional CDN$25 million in ... its stake from 30% to 40%.  Mitsui will also ... acid produced in Sarnia , providing ...
(Date:2/10/2016)... , Feb.10, 2016 ASAE is introducing a ... Management Companies (AMC) the option of joining or renewing ... fee determined by staff size, every employee in any ... ASAE and reap all available member benefits.   ... new organizational membership options will allow organizations of any ...
(Date:2/10/2016)... 2016  Matchbook, Inc., a company specializing in ... companies, announced today the appointment of Jim ... brings nearly 25 years of experience in supply ... nearly two decades in executive level roles as ... Genzyme and, most recently headed global logistics and ...
(Date:2/10/2016)... ... February 10, 2016 , ... SonaCare Medical, LLC reports ... program, Sonalinkā„¢ remote monitoring. The inaugural launch of this new technology occurred over ... Dr. Samuel Peretsman to a HIFU technical expert at SonaCare Medical headquarters. ...
Breaking Biology Technology: