diff --git a/data-raw/04_download_landsat7_data.R b/data-raw/04_download_landsat7_data.R
new file mode 100644
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+# Download Landsat 7 data to validate
+# the approach if possible with independent
+# remote sensing data - with the
+# caveat that the frequency is temporally
+# less dense
+
+# change this depending on system settings
+python_path = "/usr/local/bin/python"
+
+library(dplyr)
+
+# site info
+sites <- readr::read_csv("data/flue_stocker18nphyt.csv") |>
+  select(site) |>
+  unique()
+info <- readr::read_csv("data/site_info.csv") |>
+  filter(
+    sitename %in% !!sites$site
+    ) |>
+  select(
+    sitename,
+    lat,
+    lon,
+    date_start,
+    date_end
+  )
+
+# clone the gee_subset project
+# relies on git being installed
+# and will work out of the box for most
+# on OSX or Linux.
+
+# basic gee_subset requirements apply (working GEE install)
+setwd(here::here("src"))
+system("git clone https://github.com/khufkens/google_earth_engine_subsets.git")
+path = here::here("src/google_earth_engine_subsets/gee_subset/")
+
+# set product parameters, such as
+# product name, band(s) to query, start and end date of the range
+# and the lcoation
+product = 'LANDSAT/LE07/C02/T1_L2'
+band = "SR_B1 SR_B2 SR_B3 SR_B4 SR_B5 ST_B6 SR_B7 QA_PIXEL"
+
+info |>
+  group_by(sitename) |>
+  do({
+
+    x <- .
+
+    # location
+    location = sprintf("%s	%s", x$lat, x$lon)
+
+    # store output in the R temporary directory
+    directory = tempdir()
+
+    # make the gee_subset.py python call
+    # time the duration of the call for reporting
+    system(
+      sprintf(
+        "%s %s/gee_subset.py -p %s -b %s -s %s -e %s -l %s -d %s -sc 30",
+        python_path,
+        path,
+        product,
+        band,
+        x$date_start,
+        x$date_end,
+        location,
+        directory
+      ),
+      wait = TRUE
+    )
+
+    # read in the data stored in the temporary directory
+    df <- read.table(
+      paste0(
+        directory, "/site_",
+        tail( unlist( strsplit( product, "[/]" ) ), n=1 ), "_gee_subset.csv" ),
+      sep = ",",
+      header = TRUE,
+      stringsAsFactors = FALSE
+    )
+
+   df
+  })