Non-communicable diseases (NCDs) and climate change are two defining challenges of the twenty-first century, as each poses a significant threat to health and sustainable development.1 NCDs, including cancer, cardiovascular disease, chronic respiratory diseases, diabetes, and mental and neurological disorders, are currently responsible for 68 per cent of global mortality,2 while climate change is projected to cause several hundred thousand deaths annually by 2030.3 Risk factors for NCDs include exposure to air pollution and physical inactivity. Eighty-eight per cent of urban populations are exposed to levels of outdoor air pollution that exceed World Health Organization (WHO) Air Quality Guidelines,4 and 3.7 million deaths globally were attributable to ambient air pollution in 2012. Furthermore, urbanization leads to changes in occupation and ways of life associated with lower levels of physical activity and higher automobile use. WHO attributes 3.2 million deaths annually to physical inactivity and 1.3 million to road traffic injuries.5

These risk factors share some of the same origins and solutions as climate change, including in the energy and transportation sectors,6 and are especially relevant as urbanization increases. Rapid urbanization and population growth are major contributors to both NCDs and climate change. Urban areas facilitate activity across multiple sectors in which interventions can be made. Thus, in addition to posing formidable challenges, urban areas offer great opportunities for positive and sustainable change.

The world recently acknowledged the importance of these issues with the adoption of the 2030 Agenda for Sustainable Development, by which Governments committed to ensuring progress across 17 Sustainable Development Goals (SDGs) and 169 targets. Achieving progress on the NCD and climate change targets will depend on progress in many other priority areas and vice versa. Moving forward, it will be critical to choose interventions that aim at many targets and goals simultaneously in order to maximize impacts.

The role of parks, green spaces and waterways as urban health solutions

Parks, green spaces and waterways are important public spaces in most cities. They offer solutions to the effects of rapid, unsustainable urbanization on health and well-being. The social and economic benefits of urban green spaces are equally important, and should be viewed in the context of global issues such as climate change, as well as other priorities set out in the SDGs, including sustainable cities, public health and nature conservation.

Scientific literature describes various ways in which the natural environment can positively affect human health and well-being, as natural areas offer opportunities for physical activity, social contacts and stress reduction.7 An increasing number of epidemiological studies have demonstrated various positive health effects of maintaining urban green spaces, including improved mental health and reduced depression; improved pregnancy outcomes; and lower rates of cardiovascular morbidity and mortality, obesity and diabetes.8

Disadvantaged groups tend to live in neighbourhoods with little available green space, while studies show that socioeconomically disadvantaged individuals tend to benefit most from improved access to urban greenery. Thus, reducing socioeconomic disparities in the availability of urban green spaces can help to reduce inequalities in health related to income, minority status, disability and other socioeconomic and demographic factors.9

Increasing the number and quality of green spaces has the potential to mitigate short-lived climate pollutants that produce a strong global warming effect and contribute significantly to more than 7 million premature air-pollution related deaths annually.10 Urban fountains, ponds, lakes and roof gardens also moderate temperature extremes and reduce the Urban Heat Island effect, resulting in energy savings and improved climate quality in cities. Air pollution contributes to rising temperatures and heat wave episodes, leading to increased rates of mortality from heart attacks or stroke as a result of heat stress, particularly in people with pre-existing NCDs.11 For every tree strategically planted to provide shade, there could be a direct reduction of approximately 10 kg in carbon emissions from power plants through reduced demand for air conditioning.12 In Europe alone, 400,000 premature deaths per year occur as a result of air pollution, at a cost of €330 billion to €940 billion.13

In addition to the clear benefits of climate change mitigation and air pollution reduction, parks, green spaces and waterways help reduce exposure to a major risk factor for NCDs—physical inactivity—which causes 3.2 million deaths annually.14 Parks and green spaces provide people with the opportunity to walk and cycle more often and engage in leisure-time physical activity. Therefore, investments in city parks, green spaces, and waterways are an effective and economical way to both promote health and mitigate climate change.

Discussion

Intervention studies can help document the concrete gains in public health resulting from climate change mitigation. Cities should use this information to make decisions that will promote health, mitigate climate change and enhance the quality of life for residents. Key opportunities for health should be addressed in urban planning.

In addition, it is important to match evidence and data across sectors and promote integration of different evidence and indicators, using a Health in All Policies approach. The development and use of linked health and urban planning indicators for public spaces, transport and energy can support the adoption of key policies, as well as the monitoring and evaluation of urban interventions.

Integrating health perspectives into the many factors, disciplines and influences that shape city policies can drive cost-effective urban planning and related transport mitigation strategies. Urban and transport planning would benefit from the use of health and health-risk data for informed decision-making and priority-setting. Establishing processes through which policymakers can objectively evaluate the potential health-related impacts of an intervention before it is implemented will help ensure that solutions that advance health and climate change mitigation are found.

The health sector has a key role to play in guiding and supporting policies to protect the climate, and in promoting less polluted, healthy cities and green spaces. In addition to providing health-based guidance for air and water quality, as well as for transport and housing design, the health sector can also offer tools to support other areas, as well-tested instruments exist for assessing health impacts in transport and land-use policies. A critical element for shaping policy to promote urban health is the participation and empowerment of communities. It is important to integrate participatory processes in policymaking and implementation at both the national and local levels for effective governance to act on the social determinants of health.

Conclusion

Urban green areas offer great opportunities for positive change and the sustainable development of our cities. Public green spaces that are accessible for walking, cycling, playing and other outdoor activities can improve safe mobility and access to basic services for women, older adults and children, as well as low-income population groups, thus improving health equity. Incorporating public health priorities into public-space development provides such a co-benefit approach for urban areas. Taking a health-sensitive approach to green public-space planning offers the potential to achieve the greatest number of co-benefits.

The upcoming United Nations Conference on Housing and Sustainable Urban Development (Habitat III), to be held in Quito, Ecuador, from 17 to 20 October 2016, aims to reinvigorate the global commitment to sustainable urbanization through the adoption of a New Urban Agenda. Urban leaders can benefit from the support, credibility and local knowledge that health systems and actors can bring when recommending sustainable local policies as a measure for disease prevention and health promotion, as well as using health indicators to track progress.

Multisectoral collaboration among decision-making entities and the public will be critical, as no single ministry or Government can achieve climate goals alone. It is also important to integrate participatory processes in policymaking and implementation at both the national and local levels for effective governance to act on social determinants of health. Health perspectives can help shape city policies that drive cost-effective urban planning and related transport mitigation strategies.

This article builds on the results and reporting document for the Side Event “Public Space: An Invaluable Resource to Deliver Sustainable Urban Health”, held during Thematic Meeting on Public Spaces in April 2016 in Barcelona, Spain, in preparation for Habitat III. The following authors contributed to the above-mentioned report: Jessica Beagley of the NCD Alliance; Kristie Daniel of the HealthBridge Foundation of Canada; Nathalie Röbbel; and Florian Lorenz of Smarter Than Car. The article also acknowledges research on green spaces and health conducted at the WHO European Centre for Environment and Health.15

 

1 NCD Alliance and Global Climate and Heath Alliance, NCDs and Climate Change: Shared Opportunities for Action (2016).  Available from

https://ncdalliance.org/sites/default/files/resource_files/NCDs_%26_ClimateChange_EN.pdf.

2 World Health Organization, “Global Health Estimates 2014 Summary Tables: DALY by Cause, Age and Sex 2000-2012”, Workbook (Geneva, 2014). Available from http://www.who.int/healthinfo/global_burden_disease/GHE_DALY_Global_2000_2012.xls.

3 World Health Organization, “Climate change and health”, Fact Sheet, No. 266, Reviewed June 2016. Available from http://www.who.int/mediacentre/factsheets/fs266/en/.

4 World Health Organization, Air Quality Guidelines: Global update 2005. Particulate matter, ozone, nitrogen dioxide and sulfur dioxide (Copenhagen, 2006). Available from http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf?ua=1.

5 World Health Organization, “Road traffic injuries”, Fact Sheet, No. 358, Reviewed September 2016. Available from http://www.who.int/mediacentre/factsheets/fs358/en/.

6 NCD Alliance and Global Climate and Heath Alliance, NCDs and Climate Change, p. 4.

7 Terry Hartig and others, “Nature and health”, Annual Review of Public Health,

vol. 35, (March 2014), pp. 207-228.

8 Sjerp de Vries, “Nearby nature and human health: looking at mechanisms and their implications”, in Innovative Approaches to Researching Landscape and Health: Open Space: People Space 2, Catharine Ward Thompson, Peter Aspinall and Simon Bell, eds. (Abingdon, New York, Routledge, 2010), pp. 77-96; Mireia Gascon and others, “Residential green spaces and mortality: a systematic review”, Environment International, vol. 86 (January 2016), pp. 60-67; Takemi Sugiyama and others, “Associations of neighbourhood greenness with physical and mental health: do walking, social coherence and local social interaction explain the relationships?”, Research report,  Journal of Epidemiology and Community Health, vol. 62, No. 5 (2008), pp. e 9; Mathew White and others, “Would you be happier living in a greener urban area? A fixed-effects analysis of panel data” Psychological Science, vol. 24, No. 6 (June 2013), pp. 920-928; Kate Lachowycz and Andy Peter Jones, “Greenspace and obesity: a systematic review of the evidence”, Obesity Reviews, vol. 12 (February 2011), pp. e183-e189; Paul J. Villeneuve and others, “A cohort study relating urban green space with mortality in Ontario, Canada”, Environmental Research, vol. 115 (May 2012), pp. 51-58.

9 Jessica Allen and Reuben Balfour, “Natural solutions for tackling health inequalities”, Report (London, UCL Institute of Health Equity, 2014). Available from http://www.instituteofhealthequity.org/projects/natural-solutions-to-tackling-health-inequalities.

10 World Health Organization, Reducing global health risks through mitigation of short-lived climate pollutants, Scoping report for policymakers (Geneva, 2015). Available from http://www.who.int/phe/publications/climate-reducing-health-risks/en/.

11 Glen P. Kenny and others, “Heat stress in older individuals and patients with common chronic diseases”, Canadian Medical Association Journal, vol. 182, No.10 (July 2010), pp. 1053-1060.

12 Hashem Akbari, “Shade trees reduce building energy use and CO2 emissions from power plants”, Environmental Pollution, vol. 116 (2002), Supplement 1, pp. S119-126. Available from http://webmail.seedengr.com/documents/Shade%20trees%20reduce%20building%20energy%20use%20and%20CO2%20emissions%20from%20power%20plants.pdf.

13 Janez Potočnik, European Commissioner for Environment, “If you think the economy is more important than the environment, try holding your breath while counting your money”, Speech, Launch of the European Economic Area (EEA) Report on Air Quality 2013, Brussels, 15 October 2013. Available from http://europa.eu/rapid/press-release_SPEECH-13-822_en.htm.

14 World Health Organization, Global Health Risks: Mortality and Burden of Disease Attributable to Selected Major Risks (Geneva, 2009). Available from http://www.who.int/healthinfo/global_burden_disease/GlobalHealthRisks_report_full.pdf.    

15 World Health Organization Regional Office for Europe, Urban Green Spaces and Health (Copenhagen, (forthcoming)).