Evolution of water vapour profiles over complex terrain: observation and comparision with model simulations in the valley of Cosenza

We have measured and simulated the evolution of the diurnal water vapour profile over the Crati valley during a clear sky summer day. A twin TEA CO2 laser based dial (Differential Absorption Lidar) system has been developed to measure the water vapour profiles. The acquired data shows the vertical daily trend at a range up to 1.5 km. These measurements are compared with modelled profiles. The simulations have been performed using the CSU-RAMS model. Preliminary results show that the orography plays a fundamental role in determining the vertical distribution of water vapour and in the development of the Planetary Boundary Layer (PBL). The diurnal evolution of the PBL can be inferred from the measured profiles and, as a consequence, they can be used to improve the model. The measured and modelled vertical profiles show reasonable agreement.