This article is thin on details. But there's a lot of good stuff written about Polynesian navigation technology. I particularly liked the book Vaka Moana, which has an approachable and intelligent description of boats, cultures, navigation techniques, etc. https://www.amazon.com/Vaka-Moana-Voyages-Ancestors-Settleme...

One thing I took away from the book was that Polynesian colonization follows a pattern that looks deliberate. Specifically that they would depart on a voyage against the winds and currents, the hard way, so that they could make a swift return if they couldn't find the destination. Or at least that's what some computer modelling of the spread of Polynesian culture says. That finding is a bit at odds with this NYT article, not sure what that means.

Some other links for this NYT article:

The PNAS page (abstract only, paywall) http://www.pnas.org/content/early/2016/10/18/1612426113

Another summary with more details https://around.uoregon.edu/content/study-finds-climate-helpe...