Calculate Global Surface Water (GSW) Transitions — gsw

GSW transition data contains information about the type of surface water change for each pixel. The raster files have integer cell values between [0, 10] that code for different transition classes:

Usage

calc_gsw_transitions()

Value

A function that returns an indicator tibble with transition classes as variable and corresponding areas (in ha) as value.

Details

Value	Transition Class
1	Permanent
2	New Permanent
3	Lost Permanent
4	Seasonal
5	New Seasonal
6	Lost Seasonal
7	Seasonal to Permanent
8	Permanent to Seasonal
9	Ephemeral Permanent
10	Ephemeral Seasonal

To aggregate, we sum up the area of each transition class for a given region.

The required resources for this indicator are:

global_surface_water_transitions

Examples

# \dontrun{
library(sf)
library(mapme.biodiversity)

outdir <- file.path(tempdir(), "mapme-data")
dir.create(outdir, showWarnings = FALSE)

mapme_options(
  outdir = outdir,
  verbose = FALSE
)

aoi <- system.file("extdata", "shell_beach_protected_area_41057_B.gpkg",
  package = "mapme.biodiversity"
) %>%
  read_sf() %>%
  get_resources(get_global_surface_water_transitions()) %>%
  calc_indicators(calc_gsw_transitions()) %>%
  portfolio_long()

aoi
#> Simple feature collection with 9 features and 10 fields
#> Geometry type: POLYGON
#> Dimension:     XY
#> Bounding box:  xmin: -59.84866 ymin: 8.307999 xmax: -59.71 ymax: 8.364002
#> Geodetic CRS:  WGS 84
#> # A tibble: 9 × 11
#>   WDPAID NAME     DESIG_ENG ISO3  assetid indicator datetime            variable
#>    <dbl> <chr>    <chr>     <chr>   <int> <chr>     <dttm>              <chr>   
#> 1  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_per…
#> 2  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_new…
#> 3  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_los…
#> 4  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_sea…
#> 5  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_new…
#> 6  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_sea…
#> 7  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_per…
#> 8  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_eph…
#> 9  41057 Shell B… Managed … GUY         1 gsw_tran… 2021-01-01 00:00:00 gsw_eph…
#> # ℹ 3 more variables: unit <chr>, value <dbl>, geom <POLYGON [°]>
# }