One of the struggles with data coming from so far back is that we don't have a lot of context for it. The data may come from NASA, but NASA was founded in 1958. 60 years ago. We only have global weather data from 1880 onward. Only about 150 years. Now — that is not to say we don't have a lot of information for times before that. We can inspect CO2 levels in ice, organic material deposits in fossils, and all sorts of indirect data. Indirect — that's a very key word.
The last time we know weather affected crops in a substantial manner was the Little Ice Age
, some time between 1500-1800. Or was it 1300-1800? We're not really sure. People didn't write things down too well back then and they often spoke in riddles. It might have been caused by solar radiation cycles. Well, maybe it was volcanoes. The earth's orbital wobble could have deviated from a comet for a bit. Or maybe it was just the result of a bunch of people dying from the plague. Or maybe it was more people living in northern latitudes. We don't really know. A lot of context was lost.
I listened to about half of that YouTube earlier today and well... who knows? I don't think he provides any evidence compelling enough for me to change my life. At the same time, he could be right. What I do agree with is the need to be resilient to change. Weather is incredibly variable, and changing more and more by the day. We do know that for certain. We do not know which way our climate is headed, but it is for sure changing in dramatic ways. So I kind of look at this way: it doesn't matter if he's right or not. Practicing ways to be more resilient to changing climate is a good way to spend your time.