Impact of urban heat islands on the thermal comfort and cooling energy demand of artificial islands—A case study of AMWAJ Islands in Bahrain

Abstract

Man-made islands, created by reclaiming land from the sea, have become more prevalent in the Gulf Corporation Council countries (GCCC) in recent years as demand for additional land to develop grows. The creation of such islands will affect the landscape, climate and environment through the replacement of sand and water with hard artificial surfaces and buildings. Exposing urban man-made surfaces, such as roads and buildings, to the sun increases the temperatures of their surfaces and the atmosphere, and consequently impacts upon the local weather, building energy consumption and people's thermal comfort through the modification of microclimatic variables such air temperature, relative humidity and wind speed. The current body of work represents the results of field measurements and simulation studies that assessed modifications in urban temperatures of the man-made AMWAJ Islands in the Kingdom of Bahrain, and examined thermal comfort and cooling energy demand on the islands. This work argues that the urban temperatures of AMWAJ Islands were altered in part due to human contributions such as urban geometry, urban surfaces and land use. The modification in temperature could reach almost 5°C. In turn, thermal comfort and cooling demand within AMWAJ islands were affected by the modified temperatures. The increase in urban cooling load was within the range of 14–26% when compared with uninhabited islands. The presence of green surfaces, in conjunction with water bodies that overlap with the infrastructure, help to improve thermal comfort and consequently reduce cooling energy requirements in AMWAJ Islands.