Island
Nest Elevation Threshold
Event Signal (red, panels B–D)
Panel B always shows daily exceedance. The selector changes the red spectrum in C and D.
Spectrum Options
Actions
Reading the panels
A daily max water level vs. nest threshold; red = overwash.
B water level above threshold, zero otherwise.
C periodogram: power by frequency (cycles/day).
D same spectrum re-expressed as period (1/f). Peaks at the dotted lines mark spring-neap, lunar-month and annual return cycles.
Zooming A or B zooms both.
A. Water level time series & overwash extraction
B. Extracted event signal (magnitude & occurrence)
C. Power spectral density (periodogram)
D. Return cycle spectrum (period = 1 / frequency)
— Select an island —
Station—
Threshold—
Record (valid yrs)—
Events / events per yr—
Mean duration—
Median inter-arrival—
ACF return cycle—
Reference return cycles — selected signal
| Cycle | Peak (d) | Power | ÷ AR(1) |
|---|
Top significant periods — selected signal
| # | Period (d) | ÷ AR(1) |
|---|
Autocorrelation of daily exceedance (inverse FFT of PSD)
All islands — dominant period of daily exceedance
| Island | Ev/yr | Peak (d) | ACF (d) |
|---|