Global warming is the effect of decreased solar radiation (as compared to how much solar energy is absorbed), thus more energy added to the Earth. A new ice age in Norther Europe might slightly increase that area's albido, which would increase solar radiation and in theory mitigate global warming. But truth is, the effect of that change in albido will be very small compared to the effect of the atmospheric CO2 (which traps the solar radiation).
Europe may be colder, but somewhere else is going to be much, much hotter.