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Plot a per-pixel MHW time series from NetCDF output

Source: R/event_line3.R
event_line3.Rd

Extracts a single pixel's time series from the SST and climatology NetCDF files and produces an event_line-style plot with flame polygons. The SST and climatology data are read via the C++ backend; no external NetCDF packages are required.

Usage

event_line3(
  sst_file,
  clim_file,
  lon,
  lat,
  var_name = NULL,
  start_date = NULL,
  end_date = NULL,
  spread = 150,
  metric = "intensity_cumulative",
  event_file = NULL,
  coldSpells = FALSE
)

Arguments

sst_file

Path to the SST NetCDF file (or directory of daily files).

clim_file

Path to the climatology NetCDF from ts2clm3.

lon

Longitude of the pixel to plot.

lat

Latitude of the pixel to plot.

var_name

SST variable name. If NULL, auto-detected.

start_date, end_date

Optional date range for the plot window (character, for example "2010-01-01"). If both are NULL, the plot is centred on the most intense event (see spread).

spread

Number of days before and after the peak event to show. Default 150. Only used when start_date/end_date are not set.

metric

Event metric to use for selecting the peak event when event_file is supplied. Default "intensity_cumulative".

event_file

Optional path to event NetCDF for centring the window on the most intense event.

coldSpells

Logical. Render cold-spell (blue) or heatwave (red) flames? Default FALSE.

Value

A ggplot object that can be further customised with the standard + operator.

Examples

# \donttest{
sst_file <- system.file("extdata/sst_test.nc", package = "heatwave3")
clim_file <- tempfile(fileext = ".nc")

ts2clm3(sst_file, clim_file,
        climatologyPeriod = c("1982-01-01", "2011-12-31"))
#> Reading SST data from /tmp/RtmptnP3kw/temp_libpath10f40785ac7f0/heatwave3/extdata/sst_test.nc...
#> Grid: 2 lon x 3 lat x 14276 time = 6 pixels
#> Computing climatology with 1 thread(s)...
#> 
  1/6 pixels (16%)
  2/6 pixels (33%)
  3/6 pixels (50%)
  4/6 pixels (66%)
  5/6 pixels (83%)
  6/6 pixels (100%)
#> Writing climatology to /tmp/RtmpbqjzHu/file1626015037f1f.nc_clim.nc...
#> Done.
#> 
#> ------------------------------------------------------------------
#> Climatology written to: /tmp/RtmpbqjzHu/file1626015037f1f.nc_clim.nc
#> Rows (long format): 2,196   grid: 2 lon x 3 lat
#> 
#> Head:
#>      lon     lat doy     seas   thresh
#> 1 26.525 -34.125   1 294.4208 295.9951
#> 2 26.525 -34.125   2 294.4648 296.0311
#> 3 26.525 -34.125   3 294.5088 296.0720
#> 4 26.525 -34.125   4 294.5524 296.1133
#> 5 26.525 -34.125   5 294.5955 296.1553
#> 
#> Tail:
#>         lon     lat doy     seas   thresh
#> 2192 26.575 -34.025 362 293.5308 295.1848
#> 2193 26.575 -34.025 363 293.5672 295.2141
#> 2194 26.575 -34.025 364 293.6065 295.2460
#> 2195 26.575 -34.025 365 293.6480 295.2776
#> 2196 26.575 -34.025 366 293.6907 295.3100
#> 
#> Summary:
#>   ocean pixels (valid climatology): 6
#>   seas:   291.1 to 295.6
#>   thresh: 292.4 to 297.6
#> 
#> Examine with  hw3_export("/tmp/RtmpbqjzHu/file1626015037f1f.nc_clim.nc", n = 20)
#> or export with hw3_export("/tmp/RtmpbqjzHu/file1626015037f1f.nc_clim.nc", file_out = "out.csv")  (.csv/.rds/.parquet)
#> ------------------------------------------------------------------

event_line3(sst_file, clim_file,
            lon = 26.525, lat = -34.125,
            start_date = "2010-01-01", end_date = "2012-12-31")
#> Error: NetCDF error in open /tmp/RtmpbqjzHu/file1626015037f1f.nc: No such file or directory
# }