Lake Tahoe myth buster looks to set the record straight
SOUTH LAKE TAHOE, Calif. – Type “Lake Tahoe Facts” into Google and more than a million Web pages pop up, not all of them exhibiting the scientific rigor one might hope for when researching one of the world’s most famous lakes.
Type http://www.tahoefacts.com into a Web browser and you pull up one man’s effort to correct some of the false information floating around about Lake Tahoe.
Tahoma resident David Antonucci created the website about three years ago after growing frustrated with some of the oft-repeated falsehoods about the lake.
“I just wanted to have a place where anybody could get actual verifiable facts about the lake,” Antonucci said during a phone interview this week. “I had seen so many other websites that dealt with one or more aspects about Lake Tahoe that just had erroneous information.”
The environmental engineer talked about some of the most common myths Friday.
“I can see how people would automatically assume that, but, in fact, it’s just a property of light and clear water that, as natural sunlight penetrates into clear water, certain colors in the spectrum are absorbed, and so by 75 feet of depth all the colors are absorbed except for blue and visible violet light.”
“That’s not true, because we need not look any farther than Crater Lake in Oregon, which is of course a deeper lake, 1,934 feet, and it freezes over every year. Or we can look at Lake Baikal in Siberia, which is over a mile deep, and it freezes every year with ice thick enough to be able to lay railroad tracks on it and run a railroad. So, depth really is not the issue. The reason is our climate simply isn’t cold enough here to get the lake water temperature low enough where it begins to form ice on the surface. It’s a combination of our warmer climate and what we call surface-to-volume ratio of Lake Tahoe. The shape of the lake simply doesn’t allow it to lose heat fast enough in the winter for ice to form.”
“I have never really been able to track this one down, where it got started, but I can speculate that some genius just said, ‘Gee, the road is 72 miles, therefore the lake which is contained within the roadway must be about 72 miles,’ without actually looking at a map and seeing that the road actually shortcuts across points that jut out into the lake. So, the shoreline itself is actually 75.1 miles.”
“The width is pretty well set at about 12 miles, the east-west dimension. Where the confusion gets in is the length, which would be the north-south dimension, is barely 21 miles, 21.2 miles, but you often read that the length of Lake Tahoe is 22 miles, but actually that is the diagonal of the lake. The diagonal of the lake is actually 21.8 miles. That maximum diagonal runs from Cascade to Burnt Cedar Beach in Incline. That’s the maximum. The analogy I always draw is a TV. If you go to buy a TV they say, ‘Oh, you’re getting a 60-inch TV,’ but if you measure the length you go, ‘Wait a minute; this isn’t 60 inches; it’s 54 inches.’ So, it’s exactly like a TV; you need to talk about length, width and the diagonal measurement, and that’s where people get confused; they think the diagonal measurement is the same as the length, but its not.”
“I think where it came from is, at the Tahoe Valley airport, they used to make sky observations. So, I had some records from 21 years of observations that if you multiplied it all out it comes out to about 300 days. And I think what’s said there is there’s 300 days in which there is some sunshine. But I was also able to find probably actually a little bit better statistics. I went to a document called the Climate Atlas of the United States and it has the total number of hours of sunshine in a particular area. So, here at Lake Tahoe we have 4,446 hours of daylight each year and, of that time, at least 3,400 hours there’s sun shining, so that works out to 76 percent. Seventy-six percent of the time during the daylight hours the sun is shining, on average, is probably a better way to say it. You say ‘300 days,’ you think, ‘Oh, that was a day which is all sunny all day long,’ and it may not have been; it may have been sunny part of the day and then cloudy. I was not able to find much in the way of any data speaking to actual days of sunshine or cloudy weather, but for our region it’s probably not too far off. Reno has 251 days of clear and partly cloudy weather, Blue Canyon has 238 days of clear and partly cloudy days, so you can see it’s possible that Tahoe is higher, maybe under 300. It seems like it could be a reasonable number, but it should not be interpreted as that’s a whole day of just sunshine and no clouds.”