How weather services are improving heat health in Hong Kong, China
In recent years, Hong Kong (Special Administrative Region) has witnessed extremely rapid periods of population growth. Since 1995, its population has almost trebled to 7.43 million people, resulting in the relatively small series of islands of the territory now ranking among the top three most densely populated areas in the world (see figure 1.)
Hong Kong’s unique demography
Because of its densely populated and entirely urbanized living environment, Hong Kong faces unique challenges from environmental hazards, such as climate change and variability. One such example of this is an increased vulnerability to the urban heat island effect, meaning that its inhabitants are more susceptible to the harmful, and sometimes deadly, health effects of high temperatures and heat.
Hong Kong’s urban communities are particularly vulnerable to climate impacts due to the high incidence of high-density, and often unauthorized living arrangements, such as sub-divided flats. The unauthorized living quarters may often lack fresh air, appropriate cooling systems or access to essential services (such as energy and water). SAR Hong Kong also has an incredibly high proportion of citizens over 65 years of age, with this figure expected to rise to 27% of the entire population by 2033.
The Hong Kong Observatory
Given this uniquely vulnerable demography and the known link between weather conditions and public health, Hong Kong’s dedicated government weather forecast agency, the Hong Kong Observatory (HKO) has been studying, in collaboration with others, the impact of weather on public health with a particular focus on thermal stress. Since its establishment in 1883 the Hong Kong Observatory (HKO) has been evolving to ensure the delivery of tailored information to meet the needs of special users and various stakeholders, such as those vulnerable to heat.
Hong Kong Heat Index
To enhance the heat stress information services, HKO and the Chinese University of Hong Kong collaborated to develop the Hong Kong Heat Index (HKHI) for use in hot and humid climates using hospitalization data and heat stress measurement data. Based on the collaboration’s results, two reference criteria for HKHI were identified to establish a two-tier approach for the enhancement of the heat stress information service.
Caring of senior citizens
Previous studies suggest that thermal stress under cold and hot weather conditions is strongly linked with higher mortality and hospitalization rate in Hong Kong, particularly among the elderly. With a view to providing better care for the elderly people in Hong Kong, in recent years, HKO has been working closely with the Senior Citizen Home Safety Association, a self-financing and not-for-profit organization which provides a 24-h personal emergency support and caring service through the utilization of weather and climate information, including the study of health impact of weather and climate on senior citizens.
Some of these services include: real time weather information services, annual joint press conferences to promote provocative and timely assistance for the elderly when cold weather is expected, and the “Sky of Silver Age” weather and photo-competition and workshops to encourage the elderly people to adopt a wholesome outdoor lifestyle by maintaining an active interest in weather that affects them. The decade on collaboration between HKO and SCHSA in utilizing climate information for elderly caring services and has also been documented as one of the 40 case studies in the WMO-Who Joint Climate and Health Office publication on Climate Services for Health-Case Studies.
Urban planning and building environment design
The design and development in a crowded city like Hong Kong may have significant impacts on the urban climate (e.g. urban heat island effect, lower wind speed etc.) resulting in uncomfortable habitat and increase in energy consumption. To help mitigate these negative effects and improve the quality of living environment through integrating climatic considerations in urban planning and design, HKO provides meteorological data and expert advice for planning departments and its consultants as well as other professional bodies to establish guidelines to assess and regulate the impact of potential city/community, and building developments on air ventilation and micro-climate. Furthermore, urban climatic maps have been drawn up through analysing and evaluating climate data together with different geometric and urban development data to classify Hong Kong into different urban climatic zones, each with recommended planning and development actions.
The collaboration and interdisciplinarity being showcased by Hong Kong Observatory represents an often world-leading approach to the development and management of interventions which reduce the serious impacts of heat on public health. It should act as a compelling use-case for the potential of climate and meteorological services to create life-saving interventions in a world where increasing climate change and variability are becoming the norm.
HKO, along with other innovative Hong Kong based projects for the management of heat and public health, will be featured at the Inaugural Forum of the Global Heat Health Information Network at the University of Hong Kong on December 17-20. To register or find out more, please visit the Global Heat Health Information Network.