TY - JOUR
T1 - Planning for spectator thermal comfort and health in the face of extreme heat
T2 - The Tokyo 2020 Olympic marathons
AU - Vanos, Jennifer K.
AU - Kosaka, Eichi
AU - Iida, Akiko
AU - Yokohari, Makoto
AU - Middel, Ariane
AU - Scott-Fleming, Ian
AU - Brown, Robert D.
N1 - Funding Information:
The authors would like to thank Kauro Matsuo for her help in Tokyo with data collection, Kaitlin Cheng for her public health perspectives, and Daniel Vecellio for help with manuscript review and preparation. We would also like to thank the helpful and insightful comments from the peer reviewers. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2019/3/20
Y1 - 2019/3/20
N2 - The 2020 Olympic Games marathon will be run through the streets of Tokyo on the mornings of August 2nd and 9th, a time of year that is typically hot, sunny, and humid. Few studies have assessed the potential impact of extreme heat along the marathon course to understand the multiple factors (e.g., radiation, wind flow) affecting human thermal comfort (TC) as influenced by urban design and vegetation. The current research establishes a baseline of microclimate conditions and scenarios to estimate the projected TC along the marathon route for spectators. Mobile microclimate data (air and surface temperatures, solar radiation, humidity, wind speed) were collected along the marathon course over 15 periods in the summer of 2016 and aligned with sky view factors (SVF). Human energy budget modeling was applied to provide spatially-explicit heat budget and TC information along the route. Conditions are expected to create the most discomfort along open, sun-exposed locations, with ~50% of the area along the second half of the course resulting in ‘Hot’ (budget > 200 W m−2) or ‘Very hot’ (budget > 295 W m−2) conditions. The heat strain index frequently rises above 80% in these locations, with high humidity and low wind flow exacerbating discomfort. Buildings and trees producing a low SVF over roads and sidewalks protect spectators from the morning radiant heat, but such locations should be balanced with wind flow to optimize comfort. The modeling and spatial information can aid in preparing for and mitigating heat stress during the Olympics. Potential solutions can be implemented in collaboration with local organizers and government. This ‘research through design’ strategy can aid in preparing for and mitigating heat illness during the Olympics. Knowledge gained can be extended to other areas of Tokyo to reduce urban heat, and further provide targeted guidance for effective environmental cooling techniques for human health.
AB - The 2020 Olympic Games marathon will be run through the streets of Tokyo on the mornings of August 2nd and 9th, a time of year that is typically hot, sunny, and humid. Few studies have assessed the potential impact of extreme heat along the marathon course to understand the multiple factors (e.g., radiation, wind flow) affecting human thermal comfort (TC) as influenced by urban design and vegetation. The current research establishes a baseline of microclimate conditions and scenarios to estimate the projected TC along the marathon route for spectators. Mobile microclimate data (air and surface temperatures, solar radiation, humidity, wind speed) were collected along the marathon course over 15 periods in the summer of 2016 and aligned with sky view factors (SVF). Human energy budget modeling was applied to provide spatially-explicit heat budget and TC information along the route. Conditions are expected to create the most discomfort along open, sun-exposed locations, with ~50% of the area along the second half of the course resulting in ‘Hot’ (budget > 200 W m−2) or ‘Very hot’ (budget > 295 W m−2) conditions. The heat strain index frequently rises above 80% in these locations, with high humidity and low wind flow exacerbating discomfort. Buildings and trees producing a low SVF over roads and sidewalks protect spectators from the morning radiant heat, but such locations should be balanced with wind flow to optimize comfort. The modeling and spatial information can aid in preparing for and mitigating heat stress during the Olympics. Potential solutions can be implemented in collaboration with local organizers and government. This ‘research through design’ strategy can aid in preparing for and mitigating heat illness during the Olympics. Knowledge gained can be extended to other areas of Tokyo to reduce urban heat, and further provide targeted guidance for effective environmental cooling techniques for human health.
KW - Extreme heat
KW - Heat stress
KW - Olympics
KW - Public health
KW - Thermal comfort
KW - Urban design
UR - http://www.scopus.com/inward/record.url?scp=85058232144&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85058232144&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2018.11.447
DO - 10.1016/j.scitotenv.2018.11.447
M3 - Article
C2 - 30677956
AN - SCOPUS:85058232144
SN - 0048-9697
VL - 657
SP - 904
EP - 917
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -