Category	URL
_null	https://erddap.sams.ac.uk/erddap/categorize/standard_name/_null/index.xhtml?page=1&itemsPerPage=1000
sea_water_practical_salinity	https://erddap.sams.ac.uk/erddap/categorize/standard_name/sea_water_practical_salinity/index.xhtml?page=1&itemsPerPage=1000
time	https://erddap.sams.ac.uk/erddap/categorize/standard_name/time/index.xhtml?page=1&itemsPerPage=1000