Russian and Ukraine combined account for 29% of global wheat exports, much of that to the EU.
Near term climate change will most certainly lead to massive crop failures, particularly in currently bountiful parts of the EU.
Countries like the UK (I know not EU) already cannot feed their people without imports, something like 50% of the UKs food supply is imported.
It is nearly certain that within a few decades, perhaps even sooner, we will be at a point where there is not enough food. We've already see notable crop failures in the EU.
Most of us have grown up in a time of plenty, but that time is running short.
All of this is fairly well established, so is my "delusion" in that Putin is aware of this and acting on it?
After some conversion through various bad units of measure (bushels->pounds->calories), and assuming ~2250 calories a day average), it looks to me like current US corn production could feed somewhere around 1.6 billion people their entire yearly caloric needs, if it was actually directed entirely at feeding people as efficiently as possible.
And that is rather obviously not the only crop or source of food originating in the US.
Math sources:
https://www.nass.usda.gov/Newsroom/2022/01-12-2022.php - corn output.
https://www.washingtonpost.com/lifestyle/food/in-defense-of-... - bushel/pound/calorie conversion
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In short, I don't think it's very realistic to think that Europe is going to face a literal inability to get enough food even if the entirety of Ukraine never grew another plant again.
https://www.aljazeera.com/news/2022/2/17/infographic-russia-...
France exports 15,228,664 tonnes of wheat, not far behind the Ukraine with 17,314,278.
Other significant wheat producers in the EU include Germany, Bulgaria, Hungary, Czech Republic, Poland and Lithuania.
https://en.wikipedia.org/wiki/List_of_countries_by_wheat_exp...
What climate change would let crops fail in all corners of the EU, but not Ukraine and Russia?
Links to actual expert analyses, on the other hand, would be much appreciated.