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Calculate Degree Heating Month Index (DHMi)

calculate_dhmi.Rd

This function calculates Degree Heating Month Index (DHMi) from Lough et al (2018) and is calculated based on either monthly or daily SST data

Citation: Lough et al (2018) Increasing thermal stress for tropical coral reefs: 1871–2017 Scientific Reports 8(6079) https://www.nature.com/articles/s41598-018-24530-9

Usage

calculate_dhmi(
  sst_raster,
  timeseries = c("daily", "monthly"),
  accumulation_window = 3,
  timespan = c(12, 5)
)

Arguments

sst_raster

A SpatRaster object containing SST data. The raster should include a time dimension.

accumulation_window

time window for calculating DHMi (typically 3 or 4 months, see Table S1 in Mason et al 2024 Nature Geoscience)

timespan

start and end months for summed DHMi calculations (for example in Austral summer - November to May = c(12,5)

Value

A SpatRaster object with the computed metric.

Examples

if (FALSE) { # \dontrun{
library(terra)
sst_data <- rast("dhw_5km_12c5_a60a_4147_U1739222110146.nc")
ssta <- calculate_dhmi(sst_data, timeseries="daily", timespan = c(12, 4))
plot(ssta)
} # }