Okay, so these activities become drastically more expensive. That means that food is more expensive to grow, and to transport. This makes food from overseas harder to get.
(You might want to look at modern pea farming. I use peas because they don't seem like an exotic crop, but the process is pretty tech heavy. Peas are cheap (and fresh) because we have excellent short range weather forecasting.)
Your use of drastic and my dismissal of the problem look like competing opinions to me. I looked briefly for something about peas and didn't come up with anything, do you think a good discussion of the process would have clear information pointing to a drastic price increase?
You list scenarios where good forecasts reduce risks, but the lack of them would not stop people farming or going out on the sea.