This function converts pollution running averages in the original units (ppb, µg/m³, etc) to IMECA
Arguments
- value
a numeric vector of values to convert to IMECAs. Note that the concentration of pollutants can be measured in different ways, for NO2, and O3 a 1 hour average is used, for CO, an 8 hour average, and for SO2, PM10 and PM25 a 24 hour average is used.
- pollutant
type of pollutant. A vector of one or more of the following options:
SO2 - Sulfur Dioxide - ppb (24 hour average)
CO - Carbon Monoxide - ppm (8 hour average)
NO2 - Nitrogen Dioxide - pbb (1 hour average)
O3 - Ozone ppb (1 hour average)
PM10 - Particulate matter 10 micrometers or less (24 hour average)
PM25 - Particulate matter 2.5 micrometers or less (24 hour average)
- showWarnings
deprecated; you can use the function
suppressWarningsinstead.
Details
Air quality in Mexico City is reported in IMECAs (Índice Metropolitano de la Calidad del Aire), a dimensionless scale where all pollutants can be compared.
Note that each pollutant has different averaging periods (see the arguments section). Because of rounding error results may be off by a couple of points.
See also
For the formulas on how to convert visit: AVISO POR EL QUE SE DA A CONOCER EL PROYECTO DE NORMA AMBIENTAL PARA EL DISTRITO FEDERAL
Other convert functions:
convert_to_index()
Examples
## IMECA is a dimensionless scale that allows for the comparison of
## different pollutants
convert_to_imeca(157, "O3")
#> [1] 153
convert_to_imeca(c(450, 350, 250), rep("NO2", 3))
#> [1] 155 132 110
## Since this is PM10 the 80 is supposed to be the 24 hour average
convert_to_imeca(80, "PM10")
#> [1] 102
## warning about recycling elements in a vector
convert_to_imeca(c(157, 200), c("O3", "O3"))
#> [1] 153 196
convert_to_imeca(67, "O3")
#> [1] 48
convert_to_imeca(77, "O3")
#> [1] 63
convert_to_imeca(205, "O3")
#> [1] 201
convert_to_imeca(72, "O3")
#> [1] 53
convert_to_imeca(98, "O3")
#> [1] 103