raster does not align with shapefile after processing with rgee - r

Question

I defined a polygon:
library(rgee)
ee_Initialize()
polygon <- ee$Geometry$Polygon(
list(
c(91.17, -13.42),
c(154.10, -13.42),
c(154.10, 21.27),
c(91.17, 21.27),
c(91.17, -13.42)
))
Map$addLayer(polygon)
The polygon covers countries around south-east Asia
For each pixel in the polygon, I want to calculate monthly sum of a given band for a given year as follows:
month_vec <- 1:12
pr_ls <- list()
for(m in seq_along(month_vec)){
month_ref <- month_vec[m]
pr_ls[[m]] <-
ee$ImageCollection("NASA/NEX-GDDP")$
filterBounds(polygon)$ # filter it by polygon
select('pr')$ # select rainfall
filter(ee$Filter$calendarRange(2000, 2000, "year"))$ # filter the year
filter(ee$Filter$calendarRange(month_ref, month_ref, "month"))$ # filter the month
filter(ee$Filter$eq("model","ACCESS1-0"))$ # filter the model
sum() # sum the rainfall
}
Imagecollection_pr <- ee$ImageCollection(pr_ls)
ee_imagecollection_to_local(
ic = Imagecollection_pr,
region = polygon,
dsn = paste0('pr_')
)
Reading a single month's file
my_rast <- raster(list.files(pattern = '.tif', full.names = TRUE)[1])
Since this raster covers southeast asian countries, I downloaded the shapefile
sea_shp <- getData('GADM', country = c('IDN','MYS','SGP','BRN','PHL'), level = 0)
Plotting them on top of each other:
plot(my_rast)
plot(sea_shp, add = T)
There is a misalignment and I am not sure if it is the right raster that has been
processed for the given polygon. I also checked if their projection is same
crs(my_rast)
CRS arguments: +proj=longlat +datum=WGS84 +no_defs
crs(sea_shp)
CRS arguments: +proj=longlat +datum=WGS84 +no_defs
Both of them have the same projection as well. I cannot figure out what went wrong?
EDIT
As suggested in comments, I defined a new polygon covering Australia as follows:
polygon <- ee$Geometry$Polygon(
list(
c(88.75,-45.26),
c(162.58,-45.26),
c(162.58,8.67),
c(88.75,8.67),
c(88.75,-45.26)
)
)
Map$addLayer(polygon)
and repeated the above code. Plotting the raster again for the month of March on polygon gives me this:
Does anyone know if I can check if my raster is reversed w.r.t to polygon boundaries?

Answer 1

This seems to be related to rgdal rather than to the raster package. Some raster downloaded from GEE have data flipped with respect to y. I solved this problem, as follow:
library(rgee)
library(raster)
ee_Initialize()
polygon <- ee$Geometry$Polygon(
list(
c(91.17, -13.42),
c(154.10, -13.42),
c(154.10, 21.27),
c(91.17, 21.27),
c(91.17, -13.42)
))
month_vec <- 1:12
pr_ls <- list()
for(m in seq_along(month_vec)){
month_ref <- month_vec[m]
pr_ls[[m]] <-
ee$ImageCollection("NASA/NEX-GDDP")$
filterBounds(polygon)$ # filter it by polygon
select('pr')$ # select rainfall
filter(ee$Filter$calendarRange(2000, 2000, "year"))$ # filter the year
filter(ee$Filter$calendarRange(month_ref, month_ref, "month"))$ # filter the month
filter(ee$Filter$eq("model","ACCESS1-0"))$ # filter the model
sum() # sum the rainfall
}
Imagecollection_pr <- ee$ImageCollection(pr_ls) %>% ee_get(0)
exp1 <- ee_imagecollection_to_local(
ic = Imagecollection_pr,
region = polygon,
dsn = "pp_via_drive",
via = "drive" # please always use "drive" or "gcs" until rgee 1.0.6 release
)
# One option
gdalinfo <- try (rgdal::GDALinfo(exp1))
if (isTRUE(attr(gdalinfo, "ysign") == 1)) {
exp1_r <- flip(raster(exp1), direction='y')
}
Recent versions of the earthengine Python API causes some inconsistencies when via = "getInfo" is used, please always use via = "drive" until the release of rgee 1.0.6.

Answer 2

There does not seem to be a misalignment. To plot all these countries in one step, you could do
x <- lapply(c('IDN','MYS','SGP','BRN','PHL'), function(i) getData('GADM', country = i, level = 0))
sea_shp <- bind(x)