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2011-01-04 18:05:26.000 – Stacey Kawecki,  Observer and Meteorologist

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Warning: This comment is a lengthy, but interesting account of our recent wind measurement woes.

Yesterday it was cold and windy. We knew it was windy because we could hear it and we could feel it. However, we cannot currently measure it. Last week, the main pitot tube anemometer kicked the bucket, bit the dust, went belly up, croaked. Though it had some problems, it did pretty well for nearly ten years. On Thursday and Friday, Steve spent most of his time trying to heat the back-up Pitot tube. Thursday evening, it seemed to be working, so we put the back-up Pitot tube back up, only to be disappointed. Alas, no heat!

Friday we dissected the innards of the anemometer once more. The heaters in the Pitot tube had shorted out. We were Pitot-less. Luckily, we went well above freezing, and the R.M. Young performed its anemometer duties quite well. In addition to the R.M. Young doing its thing, a brand new Pitot tube was sent up with the New Year’s Eve gang. After more dissection and hours of Pitot surgery, we were able to get the new Pitot-tube on the back-up Pitot set-up. It was the good old switcharoo!

We tested it, and leaping lizards! It got warm, really fast! So, the next step was to put heat tape along some of the tubing, to avoid icing where it enters the tower. When we finally mounted the back-up Pitot tube anemometer and it recorded wind speeds concurrent to the R.M. Young, we were ALL elated. Forget New Year’s Eve, this was the cause for celebration! It did really well, through Sunday. We knew it was going to be a challenge to keep the back-up Pitot ice-free when temperature plunged into the icy depths of sub-zero territory. However, we hoped it would persevere.

Upon waking yesterday morning and hearing the steady rumble of a strong wind, I looked at the summit conditions. Even after all of our hard work, a stubborn ice clog had formed, rendering the Pitot-tube useless. Because we’re here to measure weather, and wind is part of that weather, we brought another anemometer out of mothballs. I believe the last time it was on the tower was in 2005. Steve spent some time wiring it and testing it yesterday – hooking it up to a logger and everything. It is the Hydro-tech Taylor anemometer; it is a spinning, heated anemometer that looks like a beefier version of the Heated No. 2 Anemometer (the famous one that recorded the 231 mph wind gust).

Because we knew it was windy, we came up with an elaborate plan to put this spinning monstrosity on the tower. We had everything ready, and even rigged it so it wouldn’t spin until we wanted it to. It probably isn’t fair to compare weather observers to World War II soldiers, but the only thing I could think of when Steve, Mike, and Ed were pushing the anemometer up, against the wind was the soldiers at Iwo Jima hoisting the flag.

Hooray! After Mike and Ed cut the wire that was keeping the anemometer from spinning, it spun, and stayed relatively ice-free. We then found out that we had put up the anemometer in 80 mph winds! Apparently, that’s how we roll.

Alas, the back-up Pitot-tube proved to be very difficult today. We brought it in to thaw it out and tested it. It seemed fine – so we put it back out, only to be disappointed. So, we tried again, doing more surgery, augmenting the heating capacity (aka, adding more heat tape) and double checking all the tubing. We even hooked it up down in the weather room, to see how it would respond to an artificial wind produced by a person. It did just fine. So, we put it outside again, only to be bitterly disappointed this time. It still didn’t work!

The good news is, we are recording good data via the Hydro-tech anemometer, and you can see the updated wind speed on the home page. However, the technical infrastructure is very complicated, and getting a graphical representation of the wind speed at this time is not exactly feasible.

 

Stacey Kawecki,  Observer and Meteorologist