The oldest medical book in the world is the Huang Di Nei Jing or Yellow Emperors Classic on Internal Medicine. Its basic tenants are that human beings are a product of nature and not separate from nature and that changes in the environment and a failure to adapt to those changes can cause detrimental changes in human health. Fluctuating temperatures and other changes, such as more severe weather events and rising sea levels, may affect people’s environments in ways that, in turn, harm their health and well-being. At the National Institute of Environmental Health Sciences (NIEHS), researchers seek to better understand how climate change-related environmental factors may affect people’s health. NIEHS has funded grants exploring the health effects of climate change for more than a decade. NIEHS is also leading a new Climate Change and Health Initiative to coordinate solutions-focused research throughout the National Institutes of Health (NIH) with an aim to reduce health consequences associated with evolving climate conditions and extreme weather events.
How Does Climate Change Affect Human Health?
While climate change is a global process, its impacts may affect communities in different and unequal ways. Some of these effects are relatively direct, as when heat waves or hurricanes cause injury and illness, and even death. Some effects of climate change are less direct and involve shifts in our environment that, in turn, can affect human health. For example, changes in temperatures and rainfall can affect the lifecycles of insects that transmit Lyme disease and West Nile virus, leading to new or varied outbreaks. Rising sea levels can worsen the flooding from hurricanes in coastal areas, leading to more people being exposed to contaminated water, pollutants, and hazardous wastes. Climate fluctuations often occur with other health stressors, such as poverty, social disadvantage, and impaired language ability, to increase vulnerability. Under-resourced and marginalized populations are most at risk.
Six environmental Evils in TCM
In traditional Chinese medicine, six types of changes in the environment can in their extremes present severe challenges to human health. Modern-day researchers are confirming much of this ancient wisdom and the effects today are becoming increasingly obvious to anyone paying attention. The six evils or extremes in climate that have a dramatic effect on human health are:
Heat –
Heat waves have become more frequent and intense, especially in the west
Summer Heat –
Rising Temperatures US average temperature has increased 1.9 degrees F
Damp –
extreme precipitation and flooding has increased across the country
Dry –
The west and southwest are experiencing all time record droughts
Cold –
Cold waves have become less frequent as the climate warms however severe winter storms have increased in intensity
Wind –
Hurricanes, tornados, and extreme wind events have increased
Climate change greatly elevates threats to human health across a wide range of illnesses and injuries, including:
- asthma,
- respiratory allergies and airway diseases,
- cancers,
- cardiovascular disease and stroke,
- foodborne diseases and malnutrition,1
- heat-related illness and deaths,
- reproductive, birth outcome, developmental effects,
- mental health and neurological disorders,
- vector-borne and zoonotic diseases,
- waterborne diseases,
- and extreme weather-related morbidity and mortality.
As with many diseases and disorders, some populations, are affected more than others including:
- children,
- older adults,
- women and pregnant women,
- persons with disabilities,
These groups among others may be disproportionally at risk. Strong evidence indicates that climate change also disproportionately adversely affects communities that experience socioeconomic, behavioral, and environmental vulnerabilities. Such communities include underserved and health-disparate populations, especially communities of color, rural populations, and those unduly burdened by exposure to environmental pollution. In the global community, these same populations, as well as all those living in extreme poverty with poor access to health and economic services, experience a higher risk of climate change consequences.
It is important to note that this list of influences, pathways, and health outcomes is not comprehensive, and the variability of these influences on health creates challenges for attribution to climate change. While the burden of disease attributable to climate change has not yet been reliably estimated, indicators point to a reversal of long-term U.S. and global trends of improvements in population health due to climate change. As the impact of climate change on human health increases, attribution becomes less important than intervention.
Most climate change and health research has been focused on documenting and understanding these emerging threats to populations around the world.
We can adapt
According to the Nei Jing, the key to a healthy lifestyle during climate change is to adapt. Drink lots of fluids in dry climates, and wear appropriate clothing suited to the weather. A rapidly growing body of research explores how climate adaptation efforts can minimize health hazards. Adaptation refers to a diverse array of institutional and environmental interventions, including urban planning, housing, transportation, air quality management, improved water systems, flood control, vector control, and changes in health services, among others. Importantly, other research has demonstrated opportunities for health co-benefits from social mobilization and system changes to mitigate climate change, including active transport, healthy buildings, and improved agricultural practices and diets.
A complementary field of study is focused on health threats posed by potential unintended side effects of actions by energy, agriculture, transportation, health care, and other sectors to mitigate climate change and protect enterprises from losses due to extreme weather or gradually changing conditions.30 These actions create “natural experiments” that are important in understanding how negative consequences can be avoided and health benefits maximized.
Responding to Climate Change
NASA is becoming a leader in research into how we can respond to climate change. NASA is a world leader in climate studies and Earth science. While its role is not to set climate policy or prescribe particular responses or solutions to climate change, its purview does include providing the robust scientific data needed to understand climate change. NASA then makes this information available to the global community – the public, policy- and decision-makers, and scientific and planning agencies around the world.
- Responding to climate change involves two possible approaches: reducing and stabilizing the levels of heat-trapping greenhouse gases in the atmosphere (“mitigation”) and adapting to the climate change already in the pipeline (“adaptation”).
- NASA’s role is to make climate data available to the global community, including the public, policy-, and decision-makers, and scientific and planning agencies.