Sadly they’re calling it Greenland: Migration rather than Greenland: Genesis, but I couldn’t be more excited, even though the first film — triumph of the human spirit notwithstanding — is one of the saddest movies I’ve sat through (about five times now!)
Also, to all those naysayers questioning how you can do a sequel set in a world where the surface has been obliterated by a comet, I believe I suggested it last December, with a plot and everything:

And then there are all those other unanswered questions: where did Nathan get his insulin from in the bunker? Was it their neighbour Deb that John was shagging pre-comet? Can we remember the difference between a comet and an asteroid, and does it even matter anymore?
According to Deadline, Greenland: Migration sees John, his wife Allison (Morena Baccarin) and young son Nathan (Roger Dale Floyd) travelling across the destroyed world looking for a place to rebuild, though probably not one of Garrity’s skyscrapers. Chris Sparling, who wrote Greenland, is writing the sequel, and Ric Roman Waugh is once again directing. The movie should start shooting next year.

COVID meant Greenland had a very staggered and often delayed roll-out across different territories across 2020 and 2021 (in the UK it is available to watch via Amazon Prime), and was still something of a surprise hit. Even the reviewers (mostly) liked it, with lots of rather grudging “wow I wasn’t expecting that!” takes, mainly over its clever use of a moderate budget and a tone which blended uplifting threads about ordinary people’s wish to help each other with impending doom.
Read my four-star review of Greenland, my article Greenland: How It Ends, and check out my Gerrystorm podcast episode on Greenland.