Having done a lot of real-time programming myself, it's really in the eye of the beholder. And there are snobs who think that nothing less than several kilohert

Having done a lot of real-time programming myself, it's really in the eye of the beholder. And there are snobs who think that nothing less than several kilohertz is real-time. But historically, "real-time" means "not batch mode" - where batch jobs are executed whenever there are available resources, in an unpredictable manner. Real-time is responding to real world input on some periodic schedule that is appropriate. In this case, one hour sounds fine for a world temperature map. Are you expecting to make minute-to-minute decisions based on the global temperature distribution? Local temperature I'd expect to be updated faster, but really it's a matter of your use-case.