When things get bad enough for all solutions to be considered, then I recommend we begin by revaluing Cannabis agriculture, manufacture and trade in the context of 21st Century crises. We must reverse the perception of value that has dominated our degenerative economic disrespect for the Natural Order and snap out of the confused perception that a "strategic food resource" can also be a Schedule One drug.
We all need to start utilizing Cannabis to its fullest potential, or go over the falls in synergistic collapse of environment, economics and social structures. Cannabis is far too valuable to be truly illegal. Unless mankind faces that reality, then in fact we are doomed much sooner and surer than anyone can imagine. If the nutritional and atmospheric benefits of Cannabis were the only things to consider they would be more than enough, but there's much much more.
Google "global broiling" if you need another thing to be really worried about. Fortunately, there is a solution, but it's an inconvenient one. And time is running out.