Air pollution data, separately for summer and winter months

Description

Air pollution data from Leeds (U.K.) city centre, collected from 1994 to 1998. The summer data set corresponds to the months of April to July inclusive. The winter data set corresponds to the months of November to February inclusive. Some outliers have been removed, as discussed by Heffernan and Tawn, 2004.

Usage

data(summer)
data(winter)

Format

Data frames with 578 (summer) and 532 (winter) observations on the following 5 variables.

O3

Daily maximum ozone in parts per billion.

NO2

Daily maximum NO2 in parts per billion.

NO

Daily maximum NO in parts per billion.

SO2

Daily maximum SO2 in parts per billion.

PM10

Daily maximum PM10 in micrograms/metre^3

Source

Provided as online supplementary material to Heffernan and Tawn, 2004:

http://www.blackwellpublishing.com/rss/Readmefiles/heffernan.htm

References

J. E. Heffernan and J. A. Tawn, A conditional approach for multivariate extreme values, Journal of the Royal Statistical society B, 66, 497 – 546, 2004

Examples

data(summer)
data(winter)