/aire.zmvm

An R package to download Mexico City air pollution data

Primary LanguageROtherNOASSERTION

Mexico City Pollution Data

Diego Valle-Jones November 22, 2017

Travis-CI Build Status AppVeyor build status
Author: Diego Valle-Jones
License: BSD_3
Status: CRAN_Status_Badge
Website: https://hoyodesmog.diegovalle.net/aire.zmvm.html

What does it do?

Tools for downloading pollution data for the Mexico City metro area. It can download real-time, daily maximum, minimum, or hourly average data for each of the pollution measuring stations or geographical zones in the Zona Metropolitana del Valle de México (greater Mexico City). It also includes the locations of all the measuring stations and a function to perform inverse distance weighting modified to work with wind direction.

Installation

You can always install the development version from GitHub:

if (!require(devtools)) {
    install.packages("devtools")
}
devtools::install_github('diegovalle/aire.zmvm')

To install the most recent package version from CRAN type:

install.packages("aire.zmvm")
library(aire.zmvm)

Note that the version on CRAN might not reflect the most recent changes made to this package.

Quick Example

The package consists mainly of four functions:

  • get_station_data to download data for each of the pollution (and wind and temperature) measuring stations.
  • get_zone_data to download data for each of the 5 geographic zones of Mexico City
  • get_latest_data to download the latest values for each of the pollution measuring stations.
  • idw360 Inverse distance weighting modified to work with degrees
library("aire.zmvm")
library("dplyr")
library("ggplot2")
library("ggseas")

o3 <- get_station_data(criterion = "MAXIMOS", # Can be one of MAXIMOS (daily maximum), 
                                                # MINIMOS (daily minimum), 
                                                # or HORARIOS (hourly average)
                       pollutant = "O3", # Can be one of "SO2", "CO", "NOX", "NO2", "NO", "O3", 
                                         # "PM10", "PM25", "WSP", "WDR", "TMP", "RH"
                       year = 2009:2017) # A numeric vector, the earliest year allowed is 1986
knitr::kable(head(o3))
date station_code pollutant unit value
2009-01-01 ACO O3 ppb 67
2009-01-02 ACO O3 ppb 71
2009-01-03 ACO O3 ppb 112
2009-01-04 ACO O3 ppb 91
2009-01-05 ACO O3 ppb 70
2009-01-06 ACO O3 ppb 71 
# Daily max among all base stations
o3_max <- o3 %>% 
  group_by(date) %>% 
  summarise(max = ifelse(all(is.na(value)),
                         NA,
                         base::max(value, na.rm = TRUE))) %>%
  na.omit()

# ozone values at which a contingencia ambiental was declared
# and the dates during which they were valid
# source: http://www.aire.cdmx.gob.mx/descargas/ultima-hora/calidad-aire/pcaa/pcaa-modificaciones.pdf
contingencia <- data.frame(ppb = c(216, 210, 205, 199, 185, 155, 155),
  start = c(2009, 2009.4973, 2010.4973, 2011.5795,  2012.6052,  2016.291, 2016.4986),
  end = c(2009.4973, 2010.4945, 2011.4945, 2012.6025,   2016.2883, 2016.4959, Inf))
max_daily_df <- tsdf(ts(o3_max$max, start = c(2009,1), frequency = 365.25))
ggplot(max_daily_df,
       aes(x = x, y = y)) + 
  geom_line(colour = "grey75", alpha = .5) +
  stat_rollapplyr(width = 30, align = "right", color = "#01C5D2") +
  #geom_vline(xintercept = 2015 + 183/365) +
  geom_segment(data = contingencia, 
               aes(x=start, y=ppb, xend=end, yend=ppb), color="darkred", linetype = 2)  +
  xlab("date") +
  ylab("parts per billion") +
  ggtitle("Maximum daily ozone concentration and 30 day rolling average", 
          subtitle = "Red lines indicate the values necessary to activate a phase I smog alert. \nData source: SEDEMA")
#> Warning: Removed 29 rows containing missing values (geom_path).