Can British wine grapes resolve a global warming question?
By Dennis T. Avery
web posted December 11, 2006
British wine grapes are suddenly in the midst of the global warming controversy.
Historic records tell us that Britain grew wine grapes 2000 years ago during the Roman Warming, and 1000 years ago during the Medieval Warming. Since 1300, however, Britain has been too cold for wine grapes. The debate: Is human-induced warming boosting British temperatures to "unnatural" levels, or is the gradual warming a repeat of previous cycles?
The website English-wine.com says there are more than 400 vineyards in Britain today, and ". . . the good news about English wine [is] how good, even superb, it can be."
It certainly sounds like Britain has gotten warmer recently, but why? The same web site has a "History" section, which reveals:
"In England [today], it is only in about 2 years in every 10 that grape production will be really good, 4 years will be average and 4 years poor or terrible—largely due to weather and/or disease exacerbated by weather." (Sounds as if we aren't quite to "wine country warmth yet, doesn't it?)
The same web site also says:
"In the 1990s the increase in the number of vineyards and the acreage under cultivation has leveled off, maybe even declined a little. There are a number of reasons for this— many English vineyards have undoubtedly been established with little knowledge of, or even concern for, their financial viability. A saying has grown up that the best way to get a small fortune is to have a large fortune and buy an English vineyard. Whilst this is cruel, it is also pretty certain that it is true."
The web site RealClimate, though it believes fervently in man-made global warming, accurately laid out the last 1000 years of British wine-making on July 12, 2006:
"The earliest documentation that is better than anecdotal is from the Domesday Book (1087 AD) . . . Selley quotes Unwin (J. Wine Research, 1990) who records 46 vineyards across Southern England [at that time] . . . production clearly declined after the 13th century, and had a modest resurgence in the 17th and 18th centuries, only to decline to historic lows in the 19th century when only 8 vineyards are recorded. . . . English and Welsh wine production started to have a renaissance in the 1950s. By 1977, there were 124 reasonable-sized vineyards in production—more than at any other time over the previous millennium."
So, British wine-making thrived during the Medieval Warming, failed during the Little Ice Age (1300 to 1850), and began to make a comeback in the 1950s, after major world temperature surges between 1850–70 and 1920–40. The uncertain quality of today's British wine grapes indicates that Britain still isn't as warm now as during the Roman and Medieval Warmings.
This argues that we're in a long, natural climate cycle. So does the fact that more than 70 percent of the planet's recent warming occurred before 1940, and thus before humans emitted much CO2. Ice cores and seabed sediments show the 1500-year cycle extending back 900,000 years, and carbon 14 isotopes say it's linked to variations in the sun's irradiance.
British wine-growers are likely to have several more moderately warmer centuries in which to prosper. And wine-lovers will have more-pleasant weather in which to enjoy the wines than they did during the cold, cloudy and stormy Little Ice Age. A reduction in fossil fuel use might be a good strategy for the future, but apparently would have little impact on earth's climate. 
Dennis T. Avery was a senior policy analyst for the U.S. State Department, where he won the National Intelligence Medal of Achievement. He is the co-author, with atmospheric physicist Fred Singer, of the book Unstoppable Global Warming—Every 1500 Years, available from Rowman & Littlefield. Readers may write him at the Center for Global Food Issues, Post Office Box 202, Churchville, VA 24421.