scripts/ee_gif-WaterOccurrence.R

In rpkgs/rgee2: Extra functions for R Google Earth Engine

library(rgee)
# ee_reattach() # reattach ee as a reserved word
ee_Initialize()

gsw <- ee$Image("JRC/GSW1_1/GlobalSurfaceWater")
occurrence <- gsw$select("occurrence")

VIS_OCCURRENCE <- list( min = 0, max = 100, palette = c("red", "blue"))
VIS_WATER_MASK <- list(palette = c("white", "black"))

# Create a water mask layer, and set the image mask so that non-water areas
# are opaque.
water_mask <- occurrence$gt(90)$selfMask()

###############################
# Initialize Map Location
###############################

# Uncomment one of the following statements to center the map.
# Map$setCenter(-90.162, 29.8597, 10)   # New Orleans, USA
# Map$setCenter(-114.9774, 31.9254, 10) # Mouth of the Colorado River, Mexico
# Map$setCenter(-111.1871, 37.0963, 11) # Lake Powell, USA
# Map$setCenter(149.412, -35.0789, 11)  # Lake George, Australia
# Map$setCenter(105.26, 11.2134, 9)     # Mekong River Basin, SouthEast Asia
# Map$setCenter(90.6743, 22.7382, 10)   # Meghna River, Bangladesh
# Map$setCenter(81.2714, 16.5079, 11)   # Godavari River Basin Irrigation Project, India
# Map$setCenter(14.7035, 52.0985, 12)   # River Oder, Germany & Poland
# Map$setCenter(-59.1696, -33.8111, 9)  # Buenos Aires, Argentina
Map$setCenter(-74.4557, -8.4289, 11)  # Ucayali River, Peru
Map$addLayer(occurrence$updateMask(occurrence$divide(100)), VIS_OCCURRENCE, "Water Occurrence (1984-2018)") +
    Map$addLayer(water_mask, VIS_WATER_MASK, "90% occurrence water mask", FALSE)