I'd say your estimates are right if things progress every year at the rate of 5x worsening each year. California will have another worse shortage of water within the next 5 years but not be completely out. India though, I can't say for certain but they have a chance at saving themselves but y'know. A good portion of humanity will survive the next 10 years, poverty will grow surely in the world but we will live on just with much more problems . I'd say as it is now we are going to be absolutely screwed unless we figure something out by 2040-50, which even then is like a 5% chance. Best of hopes for the world though. I'm not all that knowledgeable so I wont speak on crop failure but I hope we figure something out with that though.