Middle Ages were warmer than today, say scientists
Claims that man-made pollution is causing "unprecedented" global warming have been seriously undermined by new research which shows that the Earth was warmer during the Middle Ages.From the outset of the global warming debate in the late 1980s, environmentalists have said that temperatures are rising higher and faster than ever before, leading some scientists to conclude that greenhouse gases from cars and power stations are causing these "record-breaking" global temperatures.
Last year, scientists working for the UK Climate Impacts Programme said that global temperatures were "the hottest since records began" and added: "We are pretty sure that climate change due to human activity is here and it's accelerating."
This announcement followed research published in 1998, when scientists at the Climatic Research Unit at the University of East Anglia declared that the 1990s had been hotter than any other period for 1,000 years.
Such claims have now been sharply contradicted by the most comprehensive study yet of global temperature over the past 1,000 years. A review of more than 240 scientific studies has shown that today's temperatures are neither the warmest over the past millennium, nor are they producing the most extreme weather - in stark contrast to the claims of the environmentalists.
The review, carried out by a team from Harvard University, examined the findings of studies of so-called "temperature proxies" such as tree rings, ice cores and historical accounts which allow scientists to estimate temperatures prevailing at sites around the world.
The findings prove that the world experienced a Medieval Warm Period between the ninth and 14th centuries with global temperatures significantly higher even than today.
They also confirm claims that a Little Ice Age set in around 1300, during which the world cooled dramatically. Since 1900, the world has begun to warm up again - but has still to reach the balmy temperatures of the Middle Ages.
Now, of course, the environmentalists aren't going to let fact get in the way of their fantasy -- when have they ever? -- but it's nice to see one more brick in the wall. For those of us who have looked at history, and that "anecdotal evidence", this isn't a surprise at all.
Posted by Ith at April 6, 2003 1:24 PM