One use for satellite observations is to supplement in situ sampling of geographical locations where the timespan, frequency measurements, spatial dimensions or remoteness of the locations, make physical sampling impossible or impractical. One drawback is that satellite data are often rectangular, whereas geographical locations can have irregular boundaries. Examples of boundaries include marine protected areas or marine physical, biological, and ecological divisions like the Longhurst Marine Provinces.

In this tutorial we will learn how to download a timeseries of SST satellite data from an ERDDAP server, and then mask the data to retain only the data within an irregular geographical boundary (polygon). We will then plot a yearly seasonal cycle from within the boundary.

Access the python code.

Access the r code. There are two files for all of the r tutorials - the *.md files provide nice viewing of the code and the subsequent output on a web browser. The *.rmd files are best for downloading the code in a notebook format.