ISTM that "catastrophe" evokes an image of something that happens on a scale shorter than a year (e.g. I don't remember anyone talking about the averted ozone catastrophe).
Now that I think of it, a "slow catastrophe" is a really rare thing: it needs to be widespread enough so that it cannot be ameliorated by people slowly moving away from the affected area as things get worse -- otherwise the severity would be lower than a "catastrophe" would deserve -- and has to be slow. I couldn't think of any examples other than ozone one and political ones where moving away was sufficiently difficult (or made difficult on purpose).