Using greenbrown package with Landsat data - r

I have been trying to use the 'PhenologyRaster' function of the greenbrown package to model the growing season of my study area. However, everytime I run the function, I get empty outputs (e.g. the SOS.2016 layer will show as NA). My question is the following: am I having issues because I am running the function on one single year of data, or because Landsat time series are somewhat irregular (i.e. frequency of ~30 scenes per year)?
I am using the following piece of code to run the PhenologyRatser function:
PhenoTest = PhenologyRaster(landsat2016,start=c(2016,1,3),end=c(2016,12,20),freq=24,approach="Deriv",min.mean=-0.5,tsgf='TSGFspline',interpolate=TRUE)
The function is applied on a raster stack with the following characteristics:
class : RasterBrick
dimensions : 526, 591, 310866, 18 (nrow, ncol, ncell, nlayers)
resolution : 30, 30 (x, y)
extent : 604965, 622695, 4208175, 4223955 (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=10 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0
data source : in memory
names : X2016.01.03, X2016.01.19, X2016.02.04, X2016.03.07, X2016.03.23, X2016.04.24, X2016.05.10, X2016.05.26, X2016.06.27, X2016.07.13, X2016.07.29, X2016.08.14, X2016.08.30, X2016.09.15, X2016.10.01, ...
min values : -0.1964, NA, -0.5382, NA, -0.4696, -0.2197, -0.2803, -0.4274, -0.4827, -0.2631, -0.5256, -0.4856, -0.5631, -0.3204, -0.5512, ...
max values : 0.1714, NA, 0.2425, NA, 0.2061, 0.5173, 0.4583, 0.2470, 0.3629, 0.5165, 0.2981, 0.2802, 1.6199, 0.5016, 0.3007, ...

I also had the same issue. What I did was that I created a dummy series for three years and then the data were successfully run.
b.1 <- brick(r.1, r.2, r.3, r.4, r.5, r.6, r.7, r.8, r.9, r.10, r.11, r.12)
b.2 <- stack(b.2, b.2, b.2)
pheno.test <- PhenologyRaster(b.2, start=c(2016,1), freq=12, approach="White",
tsgf="TSGFspline", interpolate=T)

Related

Projecting a raster in terra fails

I have a single simple raster in EPSG:7532 that I am trying to project to EPSG:4326 but is failing
The source data is a Lidar point clould that I am able to process using the lidR package. The data source is in the link below
https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/WI_BrownRusk_2020_B20/WI_Brown_2_2020/LAZ/USGS_LPC_WI_BrownRusk_2020_B20_02531702.laz
l1 = readLAS("USGS_LPC_WI_BrownRusk_2020_B20_02531702.laz")
> l1
class : LAS (v1.4 format 6)
memory : 2.5 Gb
extent : 25349, 26849, 170258, 171758 (xmin, xmax, ymin, ymax)
coord. ref. : NAD83(2011) / WISCRS Brown (m) + NAVD88 height - Geoid18 (m)
area : 2.25 km²
points : 35.57 million points
density : 15.79 points/m²
density : 12.89 pulses/m²
convert to a spatRaster:
dsm <- rasterize_canopy(l1, res = 1.0, pitfree(c(0,2,5,10,15), c(0, 1.5)))
> dsm
class : SpatRaster
dimensions : 1500, 1501, 1 (nrow, ncol, nlyr)
resolution : 1, 1 (x, y)
extent : 25349, 26850, 170258, 171758 (xmin, xmax, ymin, ymax)
coord. ref. : NAD83(2011) / WISCRS Brown (m) (EPSG:7532)
source : memory
name : Z
min value : 185.836
max value : 333.709
The point of failure is the attempt to project to geographic format:
dsm_test <- terra::project(dsm, "EPSG:4326", method="bilinear")
> dsm_test <- terra::project(dsm, "EPSG:4326", method="bilinear")
Error: [project] cannot get output boundaries
In addition: Warning messages:
1: In x#ptr$warp(SpatRaster$new(), y, method, mask, FALSE, opt) :
GDAL Error 1: PROJ: vgridshift: could not find required grid(s).
2: In x#ptr$warp(SpatRaster$new(), y, method, mask, FALSE, opt) :
GDAL Error 1: PROJ: pipeline: Pipeline: Bad step definition: proj=vgridshift (File not found or invalid)
3: In x#ptr$warp(SpatRaster$new(), y, method, mask, FALSE, opt) :
GDAL Error 1: Too many points (961 out of 961) failed to transform, unable to compute output bounds.
A similar topic here, but seems different.
https://stackoverflow.com/questions/72404897/what-is-causing-this-raster-reprojection-error
This issue is not resulting from reprojection from EPSG:7532 to EPSG:4326 per se, but seems rather connected to the fact, that your SpatRaster object created via rasterize_canopy() comes with a vertical datum, apparently causing problems downstream:
VERTCRS["NAVD88 height - Geoid18 (m)",
VDATUM["North American Vertical Datum 1988"],
CS[vertical,1],
AXIS["up",up,
LENGTHUNIT["meter",1]],
GEOIDMODEL["GEOID18"],
ID["EPSG",5703]]]
The quick & dirty solution would be to simply override crs definition by EPSG:7532 and dropping references in Z dimension, although this does not feel 100 % right. On the other hand, I'm not sure how terra handles vertical crs information and if it is possible to keep this information at all.
library(lidR)
library(terra)
#> terra 1.6.49
l1 = readLAS("USGS_LPC_WI_BrownRusk_2020_B20_02531702.laz")
#> Warning: There are 53206 points flagged 'withheld'.
dsm <- rasterize_canopy(l1, res = 1.0, pitfree(c(0,2,5,10,15), c(0, 1.5)))
crs(dsm) <- "epsg:7532"
dsm_4326 <- project(dsm, "epsg:4326", method="bilinear")
dsm_4326
#> class : SpatRaster
#> dimensions : 1235, 1727, 1 (nrow, ncol, nlyr)
#> resolution : 1.093727e-05, 1.093727e-05 (x, y)
#> extent : -88.0786, -88.05972, 44.49092, 44.50443 (xmin, xmax, ymin, ymax)
#> coord. ref. : lon/lat WGS 84 (EPSG:4326)
#> source(s) : memory
#> name : Z
#> min value : 185.8360
#> max value : 295.1357
From my personal point of view, it would be better to have both crs (xy, z) listed in the SpatRaster summary with reproject() being able to address z-transformations separately (or have e.g. terra::transform()), e.g. when you wanted to just transform your heights but still keep EPSG:7532 as your xy reference system.
coord. ref. xy: NAD83(2011) / WISCRS Brown (m) (EPSG:7532)
coord. ref. z: NAVD88 height - Geoid18 (m) (EPSG:5703)

Save raster to USGS DEM Format in R

Similar to this question:
I would like to know how to do the reverse and save an .img raster image into a USGS DEM format.
Based on GDAL docs, it seems like it would be possible but when I run rgdal::getGDALDriverNames() in R I get the following:
name long_name create copy isRaster
139 USGSDEM USGS Optional ASCII DEM (and CDED) FALSE TRUE TRUE
which seems to imply that it won't create these files?
I was hoping to do something like:
library(raster)
# read
img <- raster("Raster_100ft_2022_10_18.img")
# convert to DEM
writeRaster(img, 'test.dem')
But raster doesn't seem to recognize that output format.
Is there some other method to save as USGS DEM files?
Thanks
For me it works with terra. If that's proper "USGSDEM" file, that's another question. From gdal reference it should save the file as well: https://gdal.org/drivers/raster/usgsdem.html
f <- system.file("ex/elev.tif", package="terra")
r <- terra::rast(f)
terra::writeRaster(r, filename = "test.dem", filetype = "USGSDEM", overwrite = TRUE)
raster::raster("test.dem")
#> class : RasterLayer
#> dimensions : 90, 95, 8550 (nrow, ncol, ncell)
#> resolution : 0.008333333, 0.008333333 (x, y)
#> extent : 5.741667, 6.533333, 49.44167, 50.19167 (xmin, xmax, ymin, ymax)
#> crs : +proj=longlat +datum=WGS84 +no_defs
#> source : test.dem
#> names : elevation
#> values : 141, 547 (min, max)
Created on 2022-10-20 with reprex v2.0.2

Trouble reading a netcdf file and convert it into a SpatRaster

I am struggling to open a NetCDF file and convert it into a raster using R. The
data is supposed to be on a regular grid of 25 km by 25 km. It contains sea
ice concentration in the Arctic.
library(terra)
#> terra 1.5.21
library(ncdf4)
file <- "~/Downloads/data_sat_Phil_changt_grid/SIC_SMMR_month_2015.nc"
I am getting a warning about the extent not found.
r <- rast(file)
#> Error in R_nc4_open: No such file or directory
#> Warning: [rast] GDAL did not find an extent. Cells not equally spaced?
We can see that there is a problem with the coordinates/extent.
r
#> class : SpatRaster
#> dimensions : 448, 304, 12 (nrow, ncol, nlyr)
#> resolution : 0.003289474, 0.002232143 (x, y)
#> extent : 0, 1, 0, 1 (xmin, xmax, ymin, ymax)
#> coord. ref. : lon/lat WGS 84
#> source : SIC_SMMR_month_2015.nc:sic
#> varname : sic
#> names : sic_1, sic_2, sic_3, sic_4, sic_5, sic_6, ...
I can open the nc file with nc_open() and I see that the coordinates are present.
nc <- nc_open(file)
names(nc$var)
#> [1] "lat" "lon" "sic"
lat <- ncvar_get(nc, "lat")
lon <- ncvar_get(nc, "lon")
dim(lat)
#> [1] 304 448
dim(lon)
#> [1] 304 448
dim(r)
#> [1] 448 304 12
Is it possible to assemble this data (the SIC values and the coordinates) to create a SpatRaster?
The nc file can be downloaded here: https://easyupload.io/pfth0s
Created on 2022-05-20 by the reprex package (v2.0.1)
The data are gridded, but the file does not specify the coordinates, nor the coordinate reference system. The file specifies the lon/lat values associated with the cells, but does not help us much, as these are clearly not on a regular grid. That is easy to see from plot(r)
NAflag(r) = -9999
plot(r,1)
And also from
p = cbind(as.vector(lon), as.vector(lat))
plot(p, cex=.1, xlab="lon", ylab="lat")
So what you need to find out, is which coordinate reference system (crs) is used, clearly some kind of polar crs. And what the extent of the data set is.
From the website you point to, I take it we can use:
crs(r) = "+proj=stere +lat_0=90 +lat_ts=70 +lon_0=-45 +k=1 +x_0=0 +y_0=0 +a=6378273 +b=6356889.449 +units=m +no_defs"
ext(r) = c(-3850000, 3750000, -5350000, 5850000)
r
#class : SpatRaster
#dimensions : 448, 304, 12 (nrow, ncol, nlyr)
#resolution : 25000, 25000 (x, y)
#extent : -3850000, 3750000, -5350000, 5850000 (xmin, xmax, ymin, ymax)
#coord. ref. : +proj=stere +lat_0=90 +lat_ts=70 +lon_0=-45 +x_0=0 +y_0=0 +a=6378273 +b=6356889.449 +units=m +no_defs
#source : SIC_SMMR_month_2015.nc:sic
#varname : sic
#names : sic_1, sic_2, sic_3, sic_4, sic_5, sic_6, ...
The results look good:
g = geodata::gadm("Greenland", level=0, path=".")
gg = project(g, crs(r))
plot(r,1)
lines(gg)
But this is of course not a good way to do such things; the ncdf file should have contained all the metadata required.

Projecting points with terra package R

I need to project longitude/latitude coordinates in the terra package, but I don't believe it is working correctly, as I am trying to extract data from a raster with this projection, but the data is not being extracted correctly.
Here's my lon/lat points and the code I am using to try to project them.
latlon_df <- structure(list(Lon = c(-103.289, -96.6735, -96.9041, -96.76864,
-102.4694, -96.6814, -97.7504, -99.6754, -96.4802, -103.0007,
-96.8897, -101.8539, -103.9717, -101.253, -99.1134, -96.5849,
-98.0301, -99.9537, -99.4601, -99.7122, -103.8278, -98.931, -102.1081,
-101.7162, -100.115, -101.3448, -100.7805, -103.5606, -96.5302,
-99.4156, -103.281, -100.0063, -97.9928, -100.7208, -98.5289,
-96.762, -96.9218, -97.1024, -103.3793, -101.0841, -102.6745,
-96.9188, -97.5154, -100.7435, -98.6938), Lat = c(45.5194, 44.3099,
43.0526, 44.3252, 45.5183, 43.7316, 45.6796, 45.4406, 44.7154,
44.0006, 43.7687, 43.9599, 43.4737, 44.9875, 45.0292, 44.0867,
45.5735, 44.9895, 44.5256, 43.5938, 43.7343, 45.7163, 45.9189,
43.1672, 45.6716, 45.9154, 45.7963, 44.6783, 44.5073, 43.7982,
43.3784, 44.2912, 43.3841, 43.2002, 44.8579, 43.5048, 43.5033,
45.1055, 44.4245, 45.4167, 44.5643, 44.304, 45.2932, 43.5601,
43.7321)), class = "data.frame", row.names = c(NA, -45L))
latlons <- terra::vect(latlon_df,geom=c('Lon','Lat'),crs="+proj=longlat")
lcc <- terra::project(latlons,"+proj=lcc +lat_0=38.5 +lon_0=262.5 +lat_1=38.5 +lat_2=38.5 +x_0=0 +y_0=0 +R=6371229 +units=m +no_defs")
var_df <- terra::extract(grib_data,lcc)[,-1]
The raster data (grib_data) I am using comes from here (it is way too big for me to put on here). https://nomads.ncep.noaa.gov/pub/data/nccf/com/hrrr/prod/hrrr.20210612/conus/hrrr.t00z.wrfsubhf00.grib2
I am not sure what I am doing wrong here, as I have used this method previously, and it seemed to work fine. Any help would be wonderful.
EDIT: The specific problem I am having is that I am not getting any different values for each lon/lat pair. The value for each variable is different, but all the values for the stations (different lon/lats are the same).
Why do you think it has to do with the projection? Either way, it appears to work for me.
url <- "https://nomads.ncep.noaa.gov/pub/data/nccf/com/hrrr/prod/hrrr.20210612/conus/hrrr.t00z.wrfsubhf00.grib2"
if (!file.exist(basename(url))) download.file(url, basename(url), mode="wb")
url <- paste0(url, ".idx")
if (!file.exist(basename(url))) download.file(url, basename(url), mode="wb")
library(terra)
r <- rast("hrrr.t00z.wrfsubhf00.grib2")
r
#class : SpatRaster
#dimensions : 1059, 1799, 49 (nrow, ncol, nlyr)
#resolution : 3000, 3000 (x, y)
#extent : -2699020, 2697980, -1588806, 1588194 (xmin, xmax, ymin, ymax)
#coord. ref. : +proj=lcc +lat_0=38.5 +lon_0=262.5 +lat_1=38.5 +lat_2=38.5 +x_0=0 +y_0=0 +R=6371229 +units=m +no_defs
#source : hrrr.t00z.wrfsubhf00.grib2
#names : 0[-] ~here", 0[-] ~tops", 0[-] ~here", 0[-] ~here", 0[-] ~face", 1000[~ound", ...
You can check of the points overlap with the raster data
plot(r, 1)
points(lcc)
And extract. It takes very long with grib files, but it does appear to work
e <- extract(r, lcc)
head(e[,c(1,6,9)])
# ID 0[-] SFC="Ground or water surface" 0[-] SFC="Ground or water surface".1
#1 1 85100 11.775471
#2 2 54400 11.087971
#3 3 79300 9.900471
#4 4 49200 10.712971
#5 5 70800 9.212971
#6 6 56600 11.400471
Make sure you have the current (CRAN) version, or perhaps the development version that you can install like this:
install.packages('terra', repos='https://rspatial.r-universe.dev')
You can speed things up a lot by doing a single read from disk (by adding zero in this example)
e <- extract(r+0, lcc)
That is not always possible and I need to do some optimization behind the scences.

Save multi layer RasterBrick to harddisk

I have a multilayer RasterBrick representing a topographic map that I want to save to the harddisk as grd or tif format, so that others can work with later.
This is the RasterBrick:
class : RasterBrick
dimensions : 2400, 4200, 10080000, 3 (nrow, ncol, ncell, nlayers)
resolution : 100, 100 (x, y)
extent : 480000, 9e+05, 62000, 302000 (xmin, xmax, ymin, ymax)
coord. ref. : NA
data source : in memory
names : layer.1, layer.2, layer.3
min values : 2.8725, 2.8725, 2.8725
max values : 254.5175, 254.5175, 254.5175
I tried to save it with this command:
outfile <- writeRaster(brick, filename='grid.tif', format="GTiff", overwrite=TRUE)
and this:
outfile <- writeRaster(m, filename='grid.grd', format="raster", overwrite=TRUE)
But the tif file is corrupt and the grd object only contains one layer and is not recognized as multi layer RasterBrick when I read it back in using raster().
The aim is to use the topographic map as background for thematic maps.
Try this:
outfile <- writeRaster(brick, filename='grid.tif', format="GTiff", overwrite=TRUE,options=c("INTERLEAVE=BAND","COMPRESS=LZW"))

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