Tuesday, June 17, 2008
Increasing Winds on the Bay
I have a theory that the average wind speeds on the San Francisco Bay are on the rise. I have been sailing the bay for the past 24 years and over the last two years it has been much windier than usual. Could it be just the ebb and flo of water temps that are causing this? Could it be in a small part due to global warming? Our winds are created by a very cold ocean and a very hot Central Valley. As the wind travels down from the northwest it causes an upwelling of cold water from the deep. As the sun shines hot on the valley the hot air rises. Think of wind like a stream of water. As the hot air rises, the cold air rushes in to take its place. The bigger the difference in temperature between the two, the higher the wind speed on the bay. Then you have this big funnel as the headlands meet near the Golden Gate Bridge and this causes the wind to be even greater. If you have ever sailed thru the "slot" on a typical summer day, you know about funnels. So my theory is that because we have had higher temps in the valley over the last few years, this increases the wind speed on the bay. Usually we have wind between 20-25 knots every day from about May to September. Lately the wind has been 30-35 knots everyday. Yesterday at Angel Island it topped out at 36. Now I am just a sailor and I don't have any data to back this up but I would love to hear from any other Bay Area sailors who have noticed this. Happy sailing and tuck in another reef!