If you're burning fossil fuels for travel anyway, burning bunker fuel is actually pretty good from a global warming point of view. Because it contains so much s

If you're burning fossil fuels for travel anyway, burning bunker fuel is actually pretty good from a global warming point of view. Because it contains so much sulphur, which has a cooling effect, it contributes a little less to warming that the CO2 tonnage suggests. Compare this with flying where the warming effect is magnified by a factor of two or three, because the emissions happen high up in the atmosphere. Of course acid rain is a concern, so the picture is more complex than my two sentence comment makes it seem.