Guess I've got my work cut out for me this weekend!
Posted on 10/23/2002 3:01:19 PM PDT by blam
Here is the forecast: Wet, then dry for 3,000 years
By Steve Connor Science Editor
24 October 2002
Here is the weather forecast for the next few hundred years – expect rain, rain and more rain before things finally settle down to a dry period lasting about 3,000 years.
This most forward-looking of forecasts is made today by scientists who have studied stormy periods in the North Atlantic dating back 14,000 years.
The geologists, who analysed sediments at the bottom of 21 lakes in the American North-east and compared them to ice cores taken in Greenland, concluded that stormy weather is heading our way.
Anders Noren and colleagues at University of Vermont in Burlington found that periods of intense rainfall follow a 3,000-year cycle and that we are just about to enter the fifth stormy period in 14 millennia.
"If this cycle continues, the frequency and severity of intense rainstorms that can cause massive flooding should continue to increase for the next several hundred years," Dr Noren said. The geologists analysed lake sediments because they wanted to determine the natural variation in the climate before human activity – notably the burning of fossil fuels – could have had any impact on the Earth's greenhouse effect.
"In each of the cores we looked for sandy layers of sediment that were washed into the lakes during rainstorm-induced floods," Dr Noren said.
"By getting radiocarbon dates on the organic materials in and around these layers, we were able to determine when floods occurred. Our main conclusions were culled from an analysis of all these lakes' flood chronologies," he said.
The research, published in the journal Nature, shows that sediments resulting from flash floods peaked regularly once every 3,000 years or so. "Our data show four peaks in storminess during the past 14,000 years, approximately 2.6, 5.8, 9.1 and 11.9 thousand years ago," the scientists say.
John Bierman, another member of the research team, points out that the discovery of the storm cycle could not be more timely. "The last big group of storms was – you guessed it – almost 3,000 years ago," he said.
Dr Noren said that although the lake sediments reflect the past climate of the New England region of the United States, it could also have implications for other parts of the North Atlantic region, including Britain.
Ice cores taken in Greenland can measure the amount of sea-spray in the atmosphere over many centuries, which is directly related to storminess in the North Atlantic region. "Certain storm records from the UK and other parts of northern Europe show periods of high storminess contemporaneous with some of the peaks in New England," Dr Noren said.
"Thus, it's probably a stretch to assume that storminess changes in lockstep across the entire North Atlantic region, but there may be some broad similarities between New England and the UK," he said.
"Even if storminess varies differently in New England and in Europe, our results suggest that Europe may experience other climatic effects in a pattern similar to that of the storm variability in New England."
Global warming can also be expected to increase the risk of severe storms in the North Atlantic so this could exacerbate the natural cycle of storminess detected by Dr Noren's team.
"If the cycle we document is continuing today, we are entering a period expected to be particularly stormy even without the influence of greenhouse warming," he said.
note to self: buy stock in umbrella companies
Guess I've got my work cut out for me this weekend!
Better consider that a long term investment. Looks like the stormy period isn't scheduled to get here for a couple hundred years.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.