Climate change projections indicate a likely 3.8°C increase in the average temperature in Australia by 2090. During summer, outdoor heat-stress causes significant thermal discomfort, altering outdoor living preferences. This paper aims to explore the neutral and critical thresholds for outdoor thermal adaptation. The paper reports on outdoor activity change during different outdoor microclimates in Darling harbour, Sydney. Results indicate that outdoor participants adjust their insulation and activity rate by an outdoor neutral thermal threshold of 28-30°C.
During summer heatwaves, public spaces are frequently warmer than human thermal comfort preferences in a majority of Australian Cities. Citizens’ preferences of public space elements and supportive features during heat-stress conditions are under particular focus in this paper. Outdoor activity choices in different thermal environments were surveyed in Adelaide from September 2013 to April 2014. This post-activity survey indicates that necessary, optional and social activities decreased during outdoor heat-stress more than any other thermal conditions.
Australia has had seven extreme heatwaves since the beginning of the 20th century. During heatwaves, public spaces in cities are frequently warmer than is confortable for humans. The regional warming projection of 2-5°C in Australia (by 2070) will be added to an existing 4-8°C extra heat in higher urban densities. This extra urban heat is because of urban structures, land cover, lifestyle and lack of landscape. Under question is how and to what extent contemporary public spaces can become more resilient to emerging higher temperatures in cities while maintaining their usability.
This document provides practical guidance for built environment professionals and regulatory agencies seeking to optimise development projects to moderate urban microclimates and mitigate urban heat island effects in major urban centres across a range of climates in Australia