Man-made clouds are safer and more powerful at both heating and cooling. They are more localized so do not need global government. They rain out within weeks and are not permanent, so mistakes can be reversed quickly. They increase plant growth which go on to remove more CO2. Free ocean wave energy can be used to create them. The energy can be reclaimed as more hydro-power and free watering of crops. They increase freshwater supplies for consumption and filling aquifers. Clouds can be used to prevent severe weather from forming. They can be used to increase humidity to reduce wild fires and turn desert into prime real estate. Clouds can also be used militarily since they can shield a battlefield from observation including IR detection, plus they can be used as a weapon to send bad weather towards an enemy. It will probably be the military that masters clouds first. It won't be the UN scientists since clouds do not further global government.
We already make man-made clouds via waste heat at factories, jet aircraft, and ocean ships. We can cheaply make more. Why cool the whole planet when we just need to cool the narrow latitude where the temperature is 32 degrees Fahrenheit. Glaciers and polar ice cannot melt a drop if the temperature is a fraction below 32 degrees.