Written by Kina Hiller
From 30 November to 11 December 2015, more than 40,000 delegates from 195 countries meet to assess the progress in dealing with climate change, negotiate agreements and set goals for reducing greenhouse gas emissions. COP21 is a crucial conference, as its primary goal is to achieve a legally binding agreement to keep global warming at the critical threshold of 2°C. Now you can ask; why is this meeting important to Global Health?
The human population has flourished through the unsustainable exploitation of Earth’s resources but faces substantial future health risks from degradation. Environmental changes pose serious threats to human health, including climate change, ocean acidification, water scarcity, land degradation, and biodiversity loss. These effects are becoming increasingly apparent from the second half of the century. As shown in Figure 1, health impacts can be direct (e.g. heat stress, floods), secondary (due to change of natural systems) or indirect (e.g. population displacement).The concept of planetary health [p. 1973], defined as “the health of human civilization and the state of the natural systems on which it depends”, detects mechanisms and thus offers an opportunity for advocacy of reforms.
How are ecosystems affected by environmental degradation?
According to a recent publication by the Rockefeller Foundation-Lancet Commission on planetary health, effects of climate change will become evident by 2100 through increased melting of ice sheets; a projected mean sea level rise of 0.52-0.98m; a surface temperature rise between 2.6-4.8°C; changes in rainfall patterns; and a higher prevalence of extreme weather events. Ocean acidity has already increased by about 26% since the industrial revolution, and will continue to rise up to 170% by 2100, leading to losses of marine animals and coral reefs and therefore negatively impacting the livelihoods of millions of people.
With population growth, water demand is projected to increase by 55% between 2000 and 2050. Renewable surface water and groundwater resources will be reduced, some areas will basically dry off. Food security and biodiversity will be additional negatively impacted by soil degradation, which is driven by land clearance and intensive farming to meet the growing demand for animal products and non-food crops for biofuel and cosmetics (oil palm cultivation is increasing by 9% annually). Toxic chemical pollution (>140,000 chemicals are estimated to be sold in the EU) and agricultural fertilizer (nitrogen and phosphorus) have furthermore been key drivers of ecosystems change, leading to biodiversity losses and unpredictable consequences.
What are the health effects?
According to WHO, “vulnerable groups are disproportionately at risk and climate change is expected to widen existing health inequalities, both between and within populations”. Human health will be negatively affected mainly by heat stress and fires; increased malnutrition and stunting due to lower agricultural productivity and loss of pollinators; higher rates of respiratory diseases due to air pollution; endocrine disruptions due to toxic chemical exposure; productivity loss of vulnerable populations; physical and mental impacts of extreme weather events; and a higher prevalence food-, water- and vector-borne diseases. For example, diarrhoeal diseases are expected to increase by 8-11% globally by 2040s, and additional people will be at risk of malaria, schistosomiasis and zoonotic diseases.
Uncertain but more severe threats include a breakdown in food supplies, conflict due to resource scarcity and migration, the vanishing of some states, and an exacerbation of poverty, impeding the realization of the SDGs. It has been estimated by the WHO that 250,000 additional deaths per year will already occur by the 2030s.
What can we do about it?
Temperature has risen by 0.85°C since 1880, and the gasses emitted so far will probably result in an unavoidable rise of around 2°C of warming. Significant reductions in emissions in the near future and sustainable development are therefore needed, with financial support of high income countries. We need legally binding agreements on the one side, and changes in consumer behavior on the other. Suggestions for more sustainable behaviors of individuals include eating less animal-products (500g beef = 100km driving on the highway); buying local, organic and packaging-free food items; using green methods of transport; buying less but sharing instead; simply being aware and communicating concerns.
Also, we as practitioners in the health sector should set good examples and aim to build up resilient and sustainable systems. In developed countries, health services account for 5-15% of the carbon emissions. We should therefore strive for energy efficiency, renewable, and greener supply and delivery chains. Adaptation strategies should include investments in surveillance and response systems, improving social and environmental determinants of health (nutrition, water, sanitation), and ensuring equal access to health services.
Climate change can be seen as the biggest threat of the century but also as the greatest opportunity to rethink and alter our behaviour. This is a call for global action before the planet strikes back!