I have bipolar type 1, not 2, but I doubt there is a major difference when it comes to light as a trigger for mood change. Definitely more light does bring on my mood upswings and/or mania. I tend to have my highest moods in the spring.

I have mostly lived in the NJ/PA area. We actually get sunny days a lot here, but obviously the days are much shorter in the cold months. I once lived in Berkeley, CA for a couple years, where it's often sunny, except some fogginess in some mornings. I wouldn't say it improved my mood situation. I recall mood elevation and depression. I also once lived in Taiwan, which lies across the Tropic of Cancer. I had both mania and depression there. Both were quite problematic. I was taken to a hospital for the depression. Then I quit my job (when manic) and went to Hong Kong and Thailand, both at a similar latitude. I was manic there until a mood crash. Situational triggers were responsible in most all cases. So, there are more factors than just light and climate.

I will say that my husband is from a central European country that tends to be cold, dark and cloudy most of the fall through spring. Many Czechs are a rather negative and depressed type bunch. My husband loves the more numerous sunny days in our area (not far from NYC and Philly).