Much of the world may recall the summer of 2003 as the time of the deadly European heat wave and the Parisian grandmothers forgotten by their vacationing kin, but to many of the wine producers I've spoken with lately, it was the first time they truly considered global warming and its potential long-term effect on their wines. But what, exactly, might that effect be? No one I talked with seemed to quite know and neither, of course, did I. And so I set out for Hamburg in search of an answer.
Though this northern German city, known mostly for its harbor and its herring, might seem an unlikely source of vinous forecasting, it's also the home of the Max Planck Institute for Meteorology, one of the world's leading centers for climate research. I had heard that one of its directors, Dr. Hartmut Grassl (recently retired), had great insights into global changes in climate and their effect on wine. I hoped Dr. Grassl might share his theories with me, perhaps over a plate of herring or, better yet, a bratwurst or two.
I'd been given Dr. Grassl's name by Alois Lageder, who'd recently staged a symposium on global warming and wine near his winery in Alto Adige, Italy. Dr. Grassl had been one of the featured speakers and served on a panel that included both winemakers and scientists. The panel predicted "an incremental increase in temperature worldwide" of two to three degrees Celsius over the next century, as well as "a probable shift northward" in the world's winemaking regions during that time. That meant that places like Sweden, Norway and north central England could become important grape-growing zones, while established locations like southern Spain and southern Portugal might simply drop off the winemaking map altogether.