threshold of 0.9 m/sec. Wind direction accuracy is +2 deg, with a resolution 
of less than 1 deg. The anemometer is calibrated annually at the National 
Bureau of Standards in Gaithersburg, MD, and is within the manufacturer's 
specifications. 
Results 
26. Annual and monthly joint probability distributions of wind speed 
versus direction were computed. Wind speeds were resolved into 3-m/sec 
intervals, whereas the directions were at 22.5-deg intervals (i.e., 16-point 
compass direction specifications). These distributions are presented as wind 
"roses," such that the length of the petal represents the frequency of occur- 
rence of wind blowing from the specified direction, and the width of the petal 
is indicative of the speed. Resultant directions and speeds were also deter- 
mined by vector-averaging the data (see Table 2). Wind statistics are pre- 
sented in Figures 6, 7, and 8. 
15 
