It's true that they are not a permanent carbon sink unless fossilised, but forests do store huge amounts of carbon, both in the living biomass and in the soil u

It's true that they are not a permanent carbon sink unless fossilised, but forests do store huge amounts of carbon, both in the living biomass and in the soil under them. There is a strong seasonal variation in atmospheric carbon (several ppm) as the northern hemisphere biomass uptakes carbon in the summer growth season.