Temperature at AO by year

Last updated 28feb05

The temperature on the platform is measured every two minutes by the laser ranging system. The platform sensor was located beneath the laser shack (T4 corner of the platform) and was then moved to the NE corner by the faa radar antenna. The processing for the temp data is:

All temps below 50 or above 110 are ignored (430 tx sometimes corrupts them).
All dates that jump by 20 days are ignored.
The daily , min, max, median temperatures are computed by first smoothing by 22 minutes then computing the min, max.
Make histograms of number of hours spent at each temperature for a year. Since there are different count for each year, scale each histogram to a complete year so you can compare different years.

The plots show the temperature by year.

Fig 1 Top. Green: max daily value, red median daily value, black min daily value. The jumps are missing data. The dashed blue lines are the start of each year.

Fig 1 Middle: The daily median value vs day of year. Color separates the different years

Fig 1 Bottom: The daily min, max (after smoothing) vs day of year. Color distinguishes the different years. The top traces are the max value while the bottom traces are the min values.

Fig 2 Top: Histogram or hours spent at each temp for the year. Different colors are different years. The histogram data was not smoothed before computing the histograms.

Fig 2 Bottom: Histogram of fraction of time spent at each temp by year.

The histogram of hours for each year has been scaled to a full year with of data (some of the years did not have as much data as some others.

Comments:

The daily median temperature varies by 6 degrees over the year.
The maxTemp-minTemp stays pretty constant over the year. The mean value is 11.5 deg F.
The maximum temperatures for the 4th quarter of each year jump down. This is probably the rain not letting the temp get as hot as usual.
4th quarter 2004 was especially rainy. The max temps are lower than the other years.
The start 2000 was a particularly cold spell where the median daily temp dropped to 64 F.
The histograms repeat pretty well year to year (2005 is only a partial year).
2004 histograms has lost some readings around 72,73 F. I don't know whether this is instrumental or real.
The 1 percent thresholds are below 65 and above 85.
These temps are measured in the air on the platform. The response of the cable system maybe a little slower than the air temp and will be affected more strongly by rain.

processing: x101/temp/tempproc.pro, doit.pro

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