bluehour

Yeah there are a lot of trees that grow up to 4ft a year (maples, firs). Buy a 10ft tree, water and fertilize it as needed, and you can shade your house in a few years.

but I wonder whether some form of dehumidification specifically, rather than just cooling, could also aid survival?

It’s a lot cheaper to just become morlocks and sleep underground during the day and emerge on the surface at night.

Solar/wind power and heat pumps and personal air conditioners are a lot more costly than LED lights to work at night.

Or worse, mass migration north/south out of the hot and humid equatorial regions.

Cat predation is the primary cause too, likely about 75% of it. https://www.fws.gov/library/collections/threats-birds