The climates of those parts of the lower atmosphere directly affected by the features of the Earth’s surface. The height of this part of the lower atmosphere varies according to the size of the influencing feature, but could be four times the height of the feature (Barry (1970) TIBG 49). Local factors commonly override the influence of larger scale macroclimatic factors (Vitt et al. (1994) Arct. & Alpine Res. 26). See Lindberg (2006) 6th Int. Conf. Urb. Climate on modelling the urban microclimate.