The Degree Days of our Lives

There’s a lot of drama that takes place at a winery – of course I am talking about what happens outside. As each day of the growing season begins and ends, another act is played out – just one more installment in the ongoing saga of the vintage. To find out what happens, you need to stay with the story until the end. There are many ups and downs, twists and turns, enemies and friends – even love affairs.  As bit players we can see the action unfold while we play our part, but we’re powerless to control the scenery and the storyline. Sure, great acting helps, but we need to have all the pieces in place for the production to be a hit. And on top of all this, we only have one chance a year to do it right; one of the most successful performances I’ve ever seen on the North Fork was in 2010.

One of the stars in this 8 month, multi-act production are Growing Degree Days or as they are famously known – GDD. GDD measures the amount of heat accumulated during the growing season – for grapes in our neck of the woods, this is calculated from March 1 – Oct. 31. It’s the average daily temperature minus a base temperature (50 degrees F.) Winegrowers have used this system for many years to determine the boundaries of local climate as well as helping to predict the quality and timing of the vintage. Cooler regions have fewer GDD and warmer regions have higher GDD.

Now for a little background story – the average GDD on the North Fork for the past 70 years is 3100 days.   During the beginning of this span – from 1940-1970 – the average GDD for the North Fork was 2932. During the 1970’s it was 2987 and from 1980 until 2001, average GDD climbed to a level of 3252. Looking at just the past decade, our average GDD is now approximately 3327. The last year we averaged a GDD lower than 3000 was in 1992. Whatever the reason, we seem to be getting warmer than ever before.

Now here’s the most exciting part – our GDD accumulation in 2010 was the highest ever recorded on Long Island – 3762 days. We were close in 1991 with 3692 , but due to higher levels of cloud cover and rain, that year never came close to earning the same level of respect. We had great vintages with with lower GDD – 1988, 1993, 1995 and 2007 to name a few, but none of those years began nor finished as early as 2010. It’s really about serendipity – not only did we have more heat than ever, we had lots of clear, sunny days and moderate rainfall – all of it wonderful for growing and ripening fruit. Is this all part of the global climate change trend? I believe it is, as do many climatologists and other scientists who have spent their lives researching this phenomenon. Others will disagree, but as Daniel Patrick Moynihan once stated “Everyone is entitled to their own opinions, but they are not entitled to their own facts.” And the facts really speak for themselves.

The vintage season truly is theater. The main difference is there are no rehearsals or run-throughs – it’s all done in one take. It’s a show staring Mother Nature and filled with lots of different cameos, ad-libs, stagehands and set designs. One thing I do know is that when the story of the 2010 vintage was over, many of us were up standing on our feet, applauding loudly and flicking our lighters (I mean cell phones) waiting for an encore…In case your wondering, I’m hoping for a reprise performance.