Table 1: Methane measurement statistics and weather conditions at a station several kilometers west of College Station during the nine investigative drives of this study. Methane mixing ratios are given in ppm, mean wind direction in cardinal directions, mean wind speed in meters per second, mean air temperatures in degrees Celsius, and pressure in millibars (with trend indicated by arrow). Methane means and standard deviations exclude all data above 2.5 ppm (methane “spikes”).
|
Route 1: Northgate |
Route 2: Southgate |
Route 3: Creek View |
| Time |
10:00 |
17:20 |
18:00 |
10:00 |
17:15 |
18:00 |
10:30 |
18:10 |
18:00 |
| Min |
1.942 |
1.972 |
1.931 |
1.940 |
2.126 |
1.967 |
1.958 |
1.971 |
2.139 |
| Max |
2.937 |
5.747 |
10.656 |
2.320 |
2.820 |
5.079 |
2.465 |
2.366 |
2.234 |
| SD |
0.036 |
0.062 |
0.074 |
0.034 |
0.039 |
0.109 |
0.060 |
0.052 |
0.019 |
| Mean |
2.007 |
2.086 |
2.044 |
2.028 |
2.225 |
2.166 |
2.081 |
2.045 |
2.183 |
| # of leaks |
2 |
2 |
12 |
0 |
4 |
5 |
0 |
0 |
0 |
| Wind dir. |
NNE |
N |
var. |
SE |
SE |
var. |
NW |
N |
SE |
| Wind speed |
5.2 |
2.1 |
calm |
4.4 |
2.7 |
calm |
<1 |
2.3 |
2.1 |
| Mean T |
17.2 |
17.8 |
20.6 |
21.3 |
21.5 |
16.9 |
20.5 |
16.6 |
20.7 |
| p trend |
1015 → |
1011 ↑ |
1015 → |
1010 → |
1008 ↓ |
1011 ↑ |
1011 → |
1007 ↓ |
1015 → |