What to do about global climate change?

Lots of BLAH but several things are clear :
- Climates are complex. Certainly more complex than we DO understand;  possibly more complex than we CAN understand (without using machines) ;
- People are in deep - ostrich mode (obvious from coverage) ;
- by combination, the two above mean that nothing will be done, until too late. (It may already be too late.)
Hence, the increasing interest in "geoengineering". But which of the many possible schemes to follow? Surely a more difficult, and important, question.

The first point is important. Many proposed schemes interfere with complex systems in complex ways. It is perfectly hard to predict the consequences. Another concern is the time LAG between action and effect and (not unreasonable ) concerns of overshooting the desired end point. Another reasonable concern is the plausible disproportionate effect of controls on people less responsible for the problem.
SO . . .  I see the simplest solution as
(1) change insolation, not the atmosphere. The atmosphere is just too complex.
(2) change the insolation in space
(3) add components  (and so effect) in small but simply additive increments.

My proposition: combine magnetic force propulsion with solar sail technology and the properties of the L1 Lagrange point.
- Orbital objects near L1 stay there with little station-keeping effort.
- This is an area around 1Gm (a million km) from Earth, on the Sun-Earth line.
- The Sun (and Earth) has a non-trivial magnetic field in the region of L1
- At L1 the area covered by the Sun is AROUND 1000km across. Area
- We have TRIED  (failed, not for relevant reasons) to launch a solar sail of around 100m diameter.
- To reduce insolation by 1%, of blocking solar sail would be needed. That is a lot of launches, but not immense. Incremental improvements will increase effectiveness of each vessel and launch.

Update : Does the Earth's magnetic field extend out to a million km (L1)?