Radar observations of kinetic and thermal energy profiles in the atmosphere

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We studied generation mechanisms of both kinetic and thermal energy in the troposphere, and their upward transport processes in the middle atmosphere. In particular, we developed new measurement techniques with the MU radar for obtaining kinetic and thermal energy profiles.It is suggested that measurements of upward flux of both momentum and heat are very important to understand dynamical coupling of different atmospheric layrs. First, time variations of horizontal wind velocity, temperature, and mixing ratio of water vapor must be determined with a good time resolution. Then, upward flux of momentum, sensible and latent heat can be estimated from a covariance between the respective parameters and the vertical wind velocity.We employed the MU radar for determinations of three components of wind velocity, and further applied the RASS (radio acoustic sounding system) technique for observations of temperature. We are additionally developing a new radar remote-sensing technique for obtaining humidity profiles, using a relation between the radar echo intensity and refractive index gradient.We have found that upward propagating gravity waves transport kinetic energy, and eventually act to decelerate the background mean winds due to wave dissipation.