Latitude: 45.95° N
Longitude: 90.28° W
Elevation: 470 m
Time zone: UT - 7 hours
The WITN station is the second site for the Measurements of Anthropogenic Gases and Natural Emissions from Tall Towers (MAGNETT) program of NOAA/CMDL. The WLEF station is located 24 km west of Park Falls, Wisconsin (pop. 3200) in the Chequamegon National Forest (about 325,000 ha). The region immediately surrounding the tower is dominated by boreal lowland and wetland forests typical of the region. The sampling platform is the WLEF television transmission tower (447 m tall). Since October, 1994, CO2 is continuously monitored at six levels on the tower (11, 30, 76, 122, 44, and 396 m), and wind speed and direction, relative humidity and temperature are measured at 76, 122, and 396 m.
A weekly flask sampling program was started in October, 1994. Filled flask pairs are returned to the Boulder laboratory and analyzed for CH4, CO, H2, CO2, and 13C/12C and 18O/16O isotope ratios in CO2. In the near future, an automated 2-channel GC will be installed at WLEF that will measure H2, CO, CH4, CFC-11 (CCl3F), CFC-113 (CCl2F-CClF2), CH3CCl3, CCl4, and CHCl3. Two calibration gases and air from each of three tower levels will be analyzed on a half-hourly cycle.
We are indebted to the Wisconsin Educational Communications Board for very generously allowing us access to the WLEF-TV transmitter tower and site, and especially to Mr. R. Strand, chief engineer at WLEF-TV, for invaluable assistance and advice.