I'm not sure about the first question. That's something I'll have to look up.
The second question I do have a slight clue. But yes. In an agricultural environment, we use fertilizers etc that boost the nutrients in the soil, so the lack of Nitrogen is not comparable to what occurs In the open world. In our civilized neck of the woods, we can combat this to a small extent through modernized farming methods, however it's the effect on the entire worlds ecosystems that will eventually get to us, based on that research. Less nutrients from plants, will affect wildlife, sealife and so on to us. Top o' the fucking food chain.
Less developed areas with current nutrient deficiencies (such as Africa) will be affected most at first, but the trickle down is glaringly apparent. Is it a game ender? No idea. Is it good? Nope.
Now I have no idea how to grasp the global warming concept. Is it man made? Is it natural? Hell, is it caused by our complex planetary orbits over millennia? No idea. Is the earth heating up? Also, no idea. I'd like to think I'm critical enough to try and sort some truth out of all this.
The problem is we live in a world where almost any information can be passed to people through media and internet without pause. We live in a world where a few pull the strings of many. Mass media is merely a tool (ie: Greta for example). Misinformation and disinformation confuses everyone into really not knowing what the fuck is going on..and with that comes fear of the unknown. And through fear comes control. Control for what? Well, one must assume that this all has an intended destination if it is a fabricated crisis. I say look as if you're looking from the eyes of the few, looking at the hordes of many, and attempt to see that perspective. I suspect that's where the truth lies.
And if it's a real deal crisis, well, who knows, maybe we are fucked. It was a good ride and I'll keep enjoying it until I'm dead