Projection Alarm Clocks

3 Comments

1. palexandersquires
   Posted August 19, 2010 at 7:57 pm | Permalink

   what type of batteries do you use ?? I can't seem to find the right one

2. Tom Loffman
   Posted October 22, 2010 at 5:00 pm | Permalink

   In a previous comment I mentioned that a similar problem occurred at HNL in the early 1970's. The response from the people in charge of maintaining the instruments was the same. It took some investigative reporting from the Star Bulletin to bring this problem to the attention of the public, and because black aviation oil was found around the instrument site, the problem was “fixed” because it was thought to be an environmental cleanup story, not a data accuracy story.

   In other words, nobody cared that the temperature records were bogus, but they did care that there was oil sludge being dumped.

   The current situation that existed until mid June at HNL reminds me very much of the same situation from the early 70's. Someone in the NWS (perhaps by NCDC in Asheville) did look over the data, and the bad data was cut from the records. I don't have my HNL information in front of me now, but I believe there is mention of this in the HNL temperature history summary.

   For many decades the “official” Honolulu temperatures were taken on the roof of the Federal Building in Downtown Honolulu. I worked there in the NWS Division of Climatology office with Saul Price and Paul Haraguchi. The average
   August high temperature for that location was 83. Once the “official” Honolulu temperatures were reported from the airport this number jumped to 88. Older books still report the 83 figure. Current books report the 88 number. Honolulu did not get 5 degrees warmer overnight.

   Normally, rooftop temperatues are too high, but the Honolulu rooftop exposure was facing into a cool, tradewind flow off the Koolau Mountains, and was always cooler than other similar readings closer to ground level. Temperatures from the airport have always been slightly warmer than nearby locatons (PTWC – Honolulu Observatory). When I lived there I had a home weather station and I always recorded cooler temperatures than the airport. Also, the temperatures reported from the Waikiki Zoo have always seemed too high.

   Fortunately for the airport location, the trade winds are fairly strong and consistent most of the time, and so heat thermals rising up off the hot surface nearby are quickly blow out to sea – most of the time.

   Another location that is reported daily and available on the NWS Honolulu Climate page, is from Kalaeloa. This used to be known as Barbers Point Naval Air Station. I wouldn't say this is a good sensor siting either, but it's easy to compare the data between it and HNL. Doing so shows that HNL has been getting steadily warmer over the past couple of years relative to Kalaeloa and reached a peak in mid June.

   What bothers me is that there doesn't seem to be anyone monitoring such discrepancies in the Honolulu forecast office. When one station drifts several degrees higher or lower than another, or other stations, there should be someone who might notice this, particularly on days when the temperatures are breaking all time records.

   And now, when Climate Change (used to know as “Global Warming”) is on the front page of every paper every day, the folks at the NWS should be particularly careful that their data is correct. Billions, and eventually, trillions of our tax dollars are at stake, and the data that underlies the science HAS to be correct.

   If the data is incorrect, then the whole “house of cards” comes tumbling down.

   My reaction to the statement that ASOS units have a tolerance of +/- 2 degrees F is one of shock. These ASOS installations cost MILLIONS of dollars each and are supposed to be “state of the art” sensors.

   Relatively inexpensive home weather stations made by Davis Instruments, or Oregon Scientific, or LaCrosse Technology, can do better than 2 degrees. Davis regularly advertises +/- 1 degree accuracy. Why can't the ASOS temperature sensors do better than 2 degrees F?

   There are many private companies that make weather sensors used in commercial applications that have calibrated accuracies in the .1 to .2 degree ranges, and only cost thousands of dollars, not millions of dollars.

   So, this 2 degree accuracy range is a bit of a public scandal in and of itself and should be looked into by our “representatives” in Congress.

3. bryanhillman
   Posted March 27, 2012 at 9:36 am | Permalink

   RT All my lax friends need to go to and check out this new amazing lacrosse technology!