Mitsugu Saito

Prediction of Wind Shift Change around Development Area Caused by Land Deformation.

It was considered that land deformation influenced on the wind shift around the development area. Statistical study was conducted on the influence of topography upon the wind directions and the wind velocity at the 60 meteorological stations (AMeDAS weather stations) in the northern Tohoku district. It was recognized that the wind were affected by the surrounding topography. It was obtained the quantitative equation (1) between the frequencies of the wind directions (F) and the deviations of inclination of the same directions (K). Fsp = -22.8 K + 5.44 (in spring) ········· (1) Equation (2) shows the relationship between the mean wind velocity and the variables K. Vsp = -3.11 K + 1.98 (in spring) ········· (2) It became possible to predict the change of the wind system around development area by the use of these equation. The case study was carried out at the quarry. As a result, it was predicted that the wind system around the quarry would change. It was considered that cutting down trees had influence on wind velocity around the development area. Wind velocity around the development area was predicted by using effect on the windbreak forest. It was predicted that there were points where wind velocity became slow by cutting down trees at the leeward side after the development. There were points where the wind velocity fast because the effect of protection against wind was lower due to the fall of leaves.