Once the plants are dead, the top soil will be blown away or washed away in any heavy rain. And once the soils gone, it'll take centuries restore, if ever.
I know Spain and Portugal rely on reservoirs for a lot of their water, a quick google would suggest even these are close to inoperably...
I was reading a report the other day which said that large swathes of Southern Spain (inland) are now experiencing North African conditions much more frequently with extreme temperatures (summer and winter) and of course a multi-year drought. Some parts will become very hard to live in as the...