Whilst Mark may have borrowed the background from the maps indicating warming one alternative to control tmeperature is to fill the atmosphere with sulphur, similar to a volcanic eruption, and thus reduce temperature.

Yes its under consideration.

Yes the colour of the sky you see will cahnge forever.

Will it work.

There is evidence that a change in the water ice balance affects volcanic activity by altering the peressure on the tectonic plates affecting pressures at the subduction zones.

As sea level rises so does that activity.

The record of past events evidences it