HOME >> BIOLOGY >> NEWS
Warmer periods in Alaskan area not confined to modern times

CHAMPAIGN, Ill. In the northwest foothills of the Alaska Range, the last 150 years have been warm by historical reckoning, scientists report. However, they note, two other lengthy periods of climatic warmth appear to have occurred in that region during the last 2,000 years.

The findings come from a comprehensive geochemical analysis of sediment samples taken from Farewell Lake in a remote, environmentally sensitive area of Alaska. The work provides the first continuous record of temperature change spanning the last two millennia from that region, they write in the Aug. 21 issue of the Proceedings of the National Academy of Sciences.

"Naturally, the big question is whether human activity is causing the current warming," said principal investigator Feng Sheng Hu, a professor of plant biology and geology at the University of Illinois. "This study, however, doesnt provide us with the analytical confidence to answer that directly. We can say that two apparently naturally occurring warm periods existed previously.

"This type of studies offer baseline information on natural climatic variability that will allow us to pursue a variety of climate-related questions,"he said. The study provides a snapshot of 2,000 years of growing seasons. Researchers analyzed lime deposits in the lake samples for their oxygen and carbon isotopic composition as well as trace-element contents. Such material is ideal for geochemical analysis and environmental reconstruction, Hu said.

The researchers concluded that warm climatic conditions occurred in A.D. 0-300 and 850-1200. During these periods, overall conditions were drier than the colder periods, they found. The initial warm period matches documented conditions in Northern Europe and wet weather in the American Southwest. The second warm period corresponds to a period known as the Medieval Climatic Anomaly.

A period of cold, reaching a peak in about A.D. 600, possibly contributed to the demise of the Kache
'"/>

Contact: Jim Barlow
b-james3@uiuc.edu
217-333-5802
University of Illinois at Urbana-Champaign
20-Aug-2001


Page: 1 2

Related biology news :

1. Warmer weather, human disturbances interact to change forests
2. Warmer world will be a sicker world, say scientists
3. Warmer climate linked to earlier frog calling
4. Higher fibre intake linked to later periods, scientists say
5. A pill for reversible suppression of periods - a new option
6. Alaskan waters growing hospitable to sharks while seals and sea lions decline
7. Betting on climate change: Alaskan gambling contest yields treasure trove of scientific data
8. Men from early middle ages were nearly as tall as modern people
9. Researchers review evolutionary history of modern algae
10. Noahs modern ark: The role of ART in conserving endangered species
11. Worlds oldest modern hummingbirds described in Science

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:7/2/2020)... , ... July 02, 2020 ... ... Systems, B.V. (MBS) has announced a publication detailing the use of its ... transcription polymerase chain reaction (RT-PCR) in 16 minutes. The article, titled "Ultra-fast ...
(Date:6/28/2020)... JUPITER, Fla. (PRWEB) , ... June 25, 2020 , ... ... will focus on innovations in accelerated Point of Care Testing solutions (POCT). Check local ... labs. Samples are collected at medical offices and are shipped to labs throughout the ...
(Date:6/23/2020)... (PRWEB) , ... June 22, 2020 , ... The field ... Typically, ligand binding assays (LBA) have dominated this area. However, the use of mass ... years. , This now necessitates the question “How do you choose which approach to ...
Breaking Biology News(10 mins):
(Date:8/12/2020)... ... August 12, 2020 , ... Inc. magazine today revealed ... in FDA compliance consulting has been named on its annual Inc. 5000 list, ... a unique look at the most successful companies within the American economy’s most ...
(Date:8/3/2020)... , ... August 03, 2020 , ... ... today announced Jim Corrigan, President and CEO has been named one of the ... cross-section of industry sectors, PharmaVoice 100 honorees are selected based on how they ...
(Date:7/31/2020)... ... 2020 , ... R3 Stem Cell International is now offering patients the opportunity ... cells total, patients may choose which extremities they would like treated. , Several studies ... Disord. 2016). At R3 International, umbilical cord tissue is obtained from a lab with ...
(Date:7/31/2020)... ... 29, 2020 , ... Diversified Technologies, Inc. has introduced a ... to drive Klystrons, TWTs, IOTs, and magnetrons. , DTI Radar Transmitter Systems ... a push-pull configuration; yielding fast fall time for a capacitive load. These all ...
Breaking Biology Technology:
Cached News: