Teh famine's a big one, yeah. Food prices go crazy, real food vanishes from many tables at middle lifestyle or lower, soy gets big again, and there are several crackdowns in cities as the agricorps start going after urban farms … they don't want the competition and this give them an excuse. Quite a few people start raising small herb gardens in windowsills or raising chickes on rooftop coops, only to have police bust in and have a corporate lawyer impound the stuff. It's a VERY rough couple of years for Aztechnology until Sirrurg goes down. (If you want to see the whole thing start, take a look at Dirty Tricks for the lowdown.)
I am definitely getting Dirty Tricks, also because it seems to be related to the Backhaven plot that SRM4 is partially about.
I'm surprised that police would crack down on urban farms in the middle of a famine, though. That can't be good for your popularity.
I am a fairly avid reader of the sourcebooks, not the fiction, but I do not recall anything about famines. Citation needed?
Yes, while some of the food corps might want to crack down on urban farming and it may have been criminalized, most corporate police are not going to enforce those laws unless it directly benefits them. Sure, they raid a gang holdout, they will tack on illegal chicken raising or if they need an excuse to search a place "suspected urban farm". But the negative publicity combined with the fact that oppressed (or even just regular folk) will fight to keep their food would make it a . . . non-cost effective exercise for Lone Star/KE/other police forces to follow. And non-corpo Police would probably say "Screw off, I'm not enforcing that" to the corpos.
It kicks off in Dirty Tricks, when Sirrurg flattens Borriqua (Puerto Rico) during a massive hurricane that parked itself over the island for a full 24 hours, with Sirrurg unleashing his dragon and spirit allies against the general populace while he, himself, completely eradicates NatVat.
A few days after that, the Atlacoya blight strikes Aztlan, ripping across the land at staggering speed, wiping out the year's corn crop and further rotting stored corn across the land, resulting in a huge famine striking the nation. They wound up having to import food from other countries and corps, which really grated teeth when they had to buy food from Horizon, who they'd been butting heads with in the Az-Am war, and resulted in a world-wide boost in food prices as some people went into panic buying mode... the profits from that helped several corps invest not long after.
It follows in the next three or four sourcebooks from there for that year, but by the next year, the nation's recovering from it. NatVat remains a non-entity, and with it gone Aztechnology's food production is badly hurt, but they're working on new alternatives since then.