Applied Problems

Abstract

The most important properties of synoptic eddies relating to their influence on the weather are the intensity and the extent of temperature disturbances they produced. The intensity of a disturbance can be defined as the difference δT_S between the temperature of the surface water layer in the eddy and the temperature of the surrounding water. Temperature disturbances result in disturbances in the fields of energy fluxes between the sea surface and the air, among which the major role is played by the fluxes of latent (LE) and sensible (H) heat. These fluxes depend on wind velocity, vertical gradients of temperature T, and specific humidity q in the near-water air layer and on its stratification. If the air transformation is ignored, the changes of fluxes H and LE in the presence of a disturbance are equal to H δT_s/(T_s − T_z) and LE δq_s/(q_s − q_z). Here the gradients are replaced by the finite differences between the values of the quantities at the sea surface and at the measurement level. The fluxes of heat, both latent and sensible, can increase several times during the air motion above a warm Gulf Stream ring and they decrease and can change sign above a cold ring. This distinction between the effects of warm and cold rings increases still further owing to the fact that warm rings are formed nearer to the continent, and in winter (i.e. in the season of maximum heat transfer) the air above them is cooler and drier whereas cold rings are formed farther from the continent and the air moving above them has time to be heated and humidified