Volcanic Eruptions in the Northern Hemisphere

Description

The volcanicNH data set contains the dates of major explosive volcanic eruptions in the Northern Hemisphere during 1851-1985.

Usage

data(volcanicNH)

Format

A data frame with 55 dates of volanic eruptions with columns:

month

number of month (1-12) in which the eruption occurred.

year

calendar year in which the eruption occurred.

Source

Solow, A.R. (1991). An exploratory analysis of the occurrence of explosive volcanism in the Northern Hemisphere, 1951-1985. Journal of the American Statistical Association, 86, 49-54.

Examples

data(volcanicNH)
eruptionDates <- volcanicNH$year +  volcanicNH$month/12
plot(eruptionDates,rep(0,length(eruptionDates)),
     xlim=c(1840,2000),ylab = "",yaxt = "n",bty = "n")