Table 20 - Page 7

Ambient Air Quality Data for the San Diego-Tijuana Area
COUNTY Ref Pollutant Unit. Yr No. of Arith. Std. Geom. Std. High 2nd Hi
# Obs. Mean Dev. Mean Dev. Read. Read.
SD SD-8 S. Dioxide ppm 91 8277 0.003 0.004 0.0016 2.58 0.04 0.03
SD SD-8 S. Dioxide ppm 92 8131 0.0049 0.0048 0.0027 3.16 0.06 0.05
TJ SD-9 Lead ug/m3 94 29 0.044 0.037 0.031 2.27 0.14 0.12
TJ SD-9 Lead ug/m3 95 11 0.101 0.061 0.082 2.11 0.22 0.16
TJ SD-9 Lead ug/m3 96 30 0.049 0.039 0.036 2.23 0.15 0.14
TJ SD-9 PM-10 ug/m3 94 29 71.3 21.2 68.3 1.35 119 105
TJ SD-9 PM-10 ug/m3 96 40 54 27.2 49.7 1.47 190 88
Source: US-Mexico Center on Air Pollution
County SD = San Diego; TJ = Tijuana
Ref. # Refers to Air Monitor; see Table 17 for monitor numbers and locations
Pollutant Pollutant measured
Unit ppm = parts per million; ug/m3 = micrograms per cubic meter of air;
Year Calendar year
No. of Obs. Number of measurements taken at each monitor
Arith. mean Arithmetic mean for hourly (daily for PM10 and Pb) of each pollutant measured
Std. Dev. Standard deviation of arithmetic mean
Geo. mean Geometric mean for hourly (daily for PM10 and Pb) of each pollutant measured
Std. Dev. Standard deviation of geometric mean
High Read. Highest pollutant hourly/daily readings
2nd. H. Read Second highest pollutant hourly/daily readings
Highest 95% pollutant concentration that 95% of the hourly/daily readings are equal to or less than.

 Table 20 - Page 1   Table 20 - Page 2   Table 20 - Page 3   Table 20 - Page 4
  Table 20 - Page 5   Table 20 - Page 6  Table 20 - Page 7  Return to Text