Is there a way to use the API to search for collections from two archives? I don't want to just run two queries, because I want to look at the relevance ranking for both sets of data together.
Entering multiple values for most parameters on our API default to OR'ing them together to return the results that match either. For example to get collections for either LaRC or SEDAC:
curl -g "https://cmr.sit.earthdata.nasa.gov/search/collections?archive_center=LaRC&archive_center=SEDAC"