A low cost, easily fabricated radiation shield for temperature measurements to monitor dry bulb air temperature in built up urban areas

Abstract

Temperature measurements for UK and world cities are often taken at local airports. These are usually on the outskirts of the urban areas and so not subject to the urban heat island (UHI) effect. Hence they are not representative of urban and city area temperatures. As most buildings are built in urban and city areas, designers need to know these temperatures. It is therefore very important to study the UHI effect and adjust the weather data used for design to include the UHI effect. This paper emanates from a project to measure the UHI effect in Greater Manchester, UK. With the advent of miniature temperature sensors and data loggers a simpler and cheaper shield was designed and produced. This paper describes the construction and testing of a new, low cost radiation shield that can accommodate a new, low cost combined miniature temperature sensor and data logger. The shield and data loggers are both tested and shown to give very reliable results. Practical application: The low cost, easily fabricated radiation shield with its miniature sensor—logger was designed to measure the dry bulb air temperature in Greater Manchester to investigate the UHI effect. The shield is designed to be mounted, with two stainless steel bands, on a lamppost column, typically at 4 m height. A telescopic pole can be used to unhook the sensor—logger for data collection. The shield can also be used to measure the dry bulb air temperature around buildings by fixing it to an external wall. Tests have shown the shield to perform well in comparison to a Stevenson screen and to greatly reduce any influence of solar irradiance.