Dark Winter - Could we be heading for a Mini Ice Age?

There are good and bad ways of dealing with Global Warming. Geoengineering techniques like Carbon Dioxide Removal (CDR), Solar Radiation Modification (SRM) such as Stratospheric Aerosol Injection (SAI) and Marine Cloud Brightening (MCB), can inadvertently trigger a "mini ice age" or cause significant regional cooling. How do these work and how real are the risks?My Novel 'Nanopunk' is set in the near future in a world recovering from a mini ice age.