Abstract

In this study, the effect of Lake Tana wind breeze on the thermal comfort of Bahir Dar city was analyzed using four biomethrological thermal comfort indices such as Thom’s Discomfort Index (DI), Relative Stain Index (RSI), Environmental Stress Index (ESI) and apparent environmental temperature (T_app). Data were collected by setting different metrological monitoring locations in the city canyons around Lake Tana to investigate how far the wind breeze went and affected the thermal comfort of the city inhabitants. The results showed that during the hottest seasons, the maximum mean wind speed, temperature, and RH were 2.53 m/s 32.6 °C and 55% respectively in the city. The maximum value of DI, RSI, ESI, and Tapp were 27, 0.32, 28, and 27.9 °C respectively. It can be concluded that people living near the coastline felt slightly more comfortable than people living far from the coastline in the hot season. This was due to the dense construction around the Lake, which prevented the wind breeze to the city. This study showed that the urban planner could reconsider the current urban planning to maximize the wind breeze of Lake Tana to circulate cold air throughout the city for societal well-being and tourism attraction.

Keywords: Thermal comfort, Lake tana wind breeze, Bahir dar city, Urban planning