 | | | Google maps www.maps.google.com
| | | | | | When the Lamorinda Weekly ran a story about three Orinda residents who have been meticulously tracking the area rainfall patterns over the past thirty years, we knew there were more local rain trackers out there-and we were thrilled to hear from some of you. So we have updated the annual rainfall chart with a few more lines of data and expanded it to reflect locations throughout Lamorinda.[see chart] We received rainfall data from two additional locations in Orinda, one in the Orinda Downs neighborhood on Dalewood Drive and one on Upper Toyonal, plus a location in Lafayette on Amber Drive. And so Moraga was not left unrepresented, we added the data from a gauge that Contra Costa County maintains at Saint Mary's College.
Looks like a jumble of lines, right? That's what we thought. The rainfall data from the various sites tend to track similarly, but there is definitely some variability. One might conclude that these data confirm that rainfall, even over a relatively small area, is quite uneven. [see map]
But Orinda resident Gene Gottfried, who has been tracking rainfall on upper El Toyonal since 1985, pointed out that it might be the gauge that's at play. Gottfried, a physician and formerly a clinical laboratory director, used a glass rain gauge until 2007-a gauge, he points out, that was uncalibrated. He then bought an electronic rain gauge and found the rainfall readings were about 20% lower than those of the glass tube. Like the good scientist that he is, he purchased a second electronic weather gauge to confirm his results, and it produced rain numbers almost identical to his first electronic gauge and much closer to Orinda's official rainfall reports.
Gottfried's Conclusion: If your rainfall measurements are consistently much higher (or lower) than the official results, your rain gauge, not your location, may be responsible.
|
Lamorinda Weekly, Moraga CA