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Metadata for NOAA/GLERL Alpena, MI Met Station

LATITUDE: 45-03-35 N
LONGITUDE: 83-25-25 W
Site online: 04 Oct 2001, relocated to current location 27 Oct 2005

LOCATION: On the Alpena Harbor Light

Site Elevation: 177.5 m above mean sea level
Lake level above sea level: 176.0 m
Base of tower above lake level: 1.5 m
Anemometer Height: 18 m above site elevation (raised from 17m on 7/5/06) (lens is 12.8m above base, plus 1.5m, plus about 3.5m extension pole=18m)
Air Temp Height: 15 m above site elevation

NOTE: On 10/27/2005, the Alpena Met Station was moved to its new location on the Alpena Harbor Light. The sensors were serviced at that time.
OLD LOCATION (for data prior to 10/27/2005): On the grounds of the Alpena water inlet plant located adjacent to the Alpena Thunder Bay National Marine Sanctuary & Underwater Preserve, 45-02-47 N, 83-26-45 W. Site Elevation: 179.1m, Anemometer: 9.1m, Air Temp: 8.2m

Wind Sensor: R.M. Young model 5103 Wind Monitor mounted on a 10' mast clamped to the light deck rail.

Temperature Sensor: CSI model 109 thermistor mounted in a naturally aspirated Gill type radiation shield mounted about 3 feet below the Wind Monitor.

Processor: CSI model CR200. This units samples the sensors every 5 seconds and is set to an averaging interval of 5 minutes.

The wind speed shown in the "18-Hour" table and in the "5-day" graph are from the 2-minute period at the top of the hour. The data listed in the link below the "18-Hour" table (today's 2-minute data) and in the "3-hour" graph are every 2 minutes.

Wind speed is the mean wind during the 2-minute recording period. Wind gust is the maximum wind during the same 2-minute recording period. Peak wind is max wind gust during entire hour.

Power: The system is run from a power supply on the AC line.

WebCam Image: See WebCam Details.

Scheme: The CR200 communicates through a LinkSys wireless bridge to a base station site located near the Thunder Bay Marine Sanctuary.

The system is interrogated by a PC from Ann Arbor running the CSI LoggerNet software connected to the internet.

Data Line for file yyyymmdd.06t.txt: The data line is space delimited and consists of the following columns in order from left to right.

1:Station ID, 6 (Alpena)
3:Day of Year
4:Time, UTC
5:Average air temperature, Deg C
6:Wind Speed average m/s
7:Wind Speed maximum, m/s
8:Wind Direction, average, degrees from (0=north, 90=east)

-99 = missing/bad data

Ron Muzzi
Marine Instrumentation Laboratory