daily_maxima: Daily maxima of geomagnetic rate-of-change data from Eskdalemuir Magnetic Observatory
Description
A dataset containing daily block maxima of the horizontal geomagnetic field rate-of-change
at the Eskdalemuir Magnetic Observatory, Scotland, United Kingdom.
The data reflect the daily extremes of geomagnetic variability, serving as indicators
of geomagnetic disturbance over the period 1999–2022.
Usage
data(daily_maxima)
Arguments
Format
A numeric vector of daily maxima of
$$R_1(t) = \sqrt{(X_t - X_{t-1})^2 + (Y_t - Y_{t-1})^2},$$
where \(X_t\) and \(Y_t\) denote the horizontal north and east components of the magnetic field, respectively.
Details
These daily maxima capture short-term geomagnetic disturbances while maintaining a sufficiently
fine temporal resolution to observe rapid changes. Like the weekly maxima, they are naturally
modelled using the Generalised Extreme Value (GEV) distribution, with location, scale, and shape
parameters \(\mu\), \(\sigma\), and \(\xi\).
data(daily_maxima)
plot(daily_maxima, type = "l", main = "Daily maxima of geomagnetic variability",
ylab = "Daily maximum rate of change (nT/min)", xlab = "Day index")