Climate Change and the Effects on Health - Comprehensive Notes

Basics of Climate Science

• Weather: State of the atmosphere over a short time frame (hour-to-hour, day-to-day, season-to-season).

• Climate: Long-term average weather patterns for specific or even global regions, that occur over seasons, years, or decades (i.e., 30 years or more).

Climate Change vs. Global Warming

• Climate Change: Any significant change in the measure of climate lasting for an extended period – changes in temperature, precipitation, or wind patterns that occur over several decades or longer.- Involves changes in average conditions + changes in variability (i.e., extreme events).

• Global Warming: Recent and ongoing rise in global average temperature near Earth’s surface due to rising concentrations of greenhouse gas emissions in the atmosphere.- Can only be stopped by reducing global emissions of carbon dioxide from fossil fuel burning.

Carbon Footprint

• Elements contributing to your carbon footprint: transport, offsets, electricity, waste, recycling, gas, fuel.

Fossil Fuels

• Examples: Coal, Natural Gas, Oil.

• The world’s primary energy source.- Releases carbon that was removed from the atmosphere millions of years ago by animal and plant life.

  • Leads to higher concentrations of $CO_2$ and higher number of pollutants in the atmosphere.

  • Pollutants get into drinking water and food.

  • Cause respiratory and cardiovascular problems.

Greenhouse Gases

• Carbon Dioxide ($CO_2$): Makes up the vast majority of greenhouse gas emissions from fossil fuel and biomass burning. Currently, there are 426 parts per million carbon dioxide levels in the atmosphere.- Other greenhouse gases include: Methane, Nitrous oxide, Chlorofluorocarbons, Water vapor.

  • Greenhouse Gases absorb radiant energy that would normally escape the atmosphere.

  • Heat is trapped within the Earth’s atmosphere, acting like a blanket around the planet.

The Greenhouse Effect

• Energy released back into space is reduced as greenhouse gasses trap heat.

• Key greenhouse gases: $CH<em>4$, $CO</em>2$, $CF<em>6$, $NO</em>2$

Global Warming Thresholds

• Exceeding 1.5°C global warming could trigger multiple climate tipping points.

• Examples of Cascades:-

  • Arctic winter sea ice collapse.

  • Boreal forest northern expansion and southern dieback.

  • Greenland ice sheet collapse.

  • Boreal permafrost abrupt thaw and collapse.

  • Atlantic Meridional Overturning Circulation collapse.

  • Amazon rainforest dieback.

  • Mountain glaciers loss.

  • West Antarctic ice sheet collapse.

  • Low-latitude coral reefs die-off.

Climate Change Impacts across Canada

• Permafrost degradation affecting northern infrastructure.

• Reduced ice cover affecting economic development and Indigenous ways of life.

• Changing animal distributions affecting food supply.

• Increased pests affecting forest productivity and fire activity.

• Reduced glacier cover affecting western water resources and hydropower production.

• Reduced reliability of ice roads affecting access to remote mine sites and northern communities.

• Incidents of drought affecting forests and agriculture.

• Lower Great Lakes water levels affecting shipping, hydropower production, and recreation.

• Sea-level rise and increased coastal erosion affecting infrastructure and heritage sites.

• Increased temperatures affecting human health due to heat stress and vector-borne diseases.

Planetary Health

• The health of human civilization and the natural systems on which it depends.

• Transition from an Ego model to an Eco one, where our role is embedded within the natural world rather than separate from it.

Costs Associated with Societal Changes

• Increased carbon dioxide emissions in the atmosphere.

• Global ocean acidification.

• Increased world primary energy use.

• Global tropical forest loss compared with 1700 baseline (%)

• Water use (thousand $km^3$).

• Global fertiliser use (nitrogen, phosphorus, and potassium; thousand tonnes).

Social Determinants of Health

• How your society views and values you can influence your health

• A specific group of social and economic factors within the broader determinants of health.

• These relate to an individual's place in society, such as income, education, or employment.

• Experiences of discrimination, racism, and historical trauma are important social determinants of health for certain groups such as Indigenous Peoples, LGBTQ and Black Canadians.

• Key Social Determinants: Income, Education and Literacy, Employment and Working Conditions, Gender, Social Support and Coping - Resiliency

SDOH, Intersectionality and Climate Change

• Overlapping factors: religion, ethnicity, gender, class, age, culture, (dis)ability, sexuality.

Vulnerable Populations – Infants and Children

• Heart rate decreases with age while BP increases.

• Children have efficient compensatory mechanisms, maintaining BP until large intravascular losses (~ 25%).

• Cardiac arrest in children is rarely sudden, usually due to a progression of respiratory distress or shock.

• Children can’t increase their cardiac output in the same way adults can:-

  • Cardiac output = HR x Stroke Volume

  • Adults can increase stroke volume by increasing inotropy (stronger contractions) while also increasing heart rate.

  • Infants & young children can only increase chronotropy (heart rate).

  • Heart rate = significant clinical marker when monitoring cardiac output

  • Bradycardia = trouble

SDoH, Climate Change and Health: Racism & Discrimination

• Environmental Racism: Defined in 1982 by Benjamin Chavis, a Black civil rights leader.

Equality vs. Equity vs. Liberation

• Equality: sameness.

• Equity: fairness.

• Liberation: justice.

Direct vs. Indirect Health Effects

• Direct: A primary effect associated with climate change. E.g., heat-related illness, death from extreme weather events, or worsening of existing health conditions. Also includes the spread of infectious diseases, mental health challenges, disruption in essential systems such as food and water.

• Indirect: A secondary effect associated with climate change. Result of ways climate change changes natural systems and human infrastructure. E.g., malnutrition due to changes in access to nutritious foods and water, mental health impacts from displacement (often related to loss of land).

Upstream vs. Downstream Initiatives

• Upstream: Focuses on prevention by looking at root causes (social, economic, and environmental conditions) of poor health.

• Downstream: Focuses on treatment – the immediate health needs of people through healthcare services and interventions.

Definition of Health

• In 1947, The World Health Organization defined health as:-

  • “…a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.”

  • Enjoying the highest level of health represents a fundamental right of every human being “without distinction of race, religion, political belief, economic or social condition.”

  • Having health is fundamental to attaining peace and security.

Temperature: Physical Changes

• Changes in physical environment such as the polar vortex.

Respiratory Conditions

• Comparison of airways of a person without asthma vs. with asthma (inflammation and constriction).

Climate Change-Related Disasters

• Local cultural, economic, social, developmental and environmental context.

• Damage to landscape and agriculture leads to direct (smoke, burns, heat) and indirect (food supply) trauma, solastalgia.

• Communities experience economic, social, demographic impacts.

• Physical health is affected, leading to acute/chronic conditions.

• Mental health is affected, leading to loss of livelihoods, poverty, isolation, alienation, grief, bereavement, displacement.

• Causal, reciprocal relationship between physical and mental health.

Sources of Air Pollution

• Outdoor air pollution affects urban and rural areas and is caused by multiple factors.

• Sources: Industry & Energy Supply, Transport, Dust, Agricultural Practices, Household Energy, Waste Management.

Wildfires

• Defined as “fires taking place in forest or brush grasslands that cover extensive areas and usually do extensive damage.”

• Pollutants contained in wildfire smoke: CO, $CO<em>2$, NOx, $O</em>3$, $PM<em>{2.5}$, $PM</em>{10}$, volatile organic compounds (VOCs), metals (mercury).

• Expected to double by 2050.

• Significant public health impacts: Injuries, respiratory impairment, displacement of people, isolation, long-term mental health effects.

Health Risks of High Temperatures

• Immediate health issues: Dehydration, Heat exhaustion, Heat stroke, Sudden cardiac arrest.

• Longer-term health issues: Kidney disease/kidney stones, Renal failure.

Non-Communicable Diseases (NCDs)

• Contribute to 70% of deaths worldwide (82% of which take place in low/middle-income countries).-

  • Examples: Cardiovascular Disease, Respiratory Diseases, Mental Health Conditions, Diabetes, Cancer, Gastrointestinal, Neurological.

    • Screening and Identifying: Several contributing risk factors, Modifiable versus Non-Modifiable Risk Factors

Infectious Diseases

• Vector-Borne Diseases: Carried and transmitted by vectors (living organisms that can transmit infectious pathogens between humans, or from animals to humans). Examples of vectors include mosquitoes, fleas, ticks.-

  • Caused by parasites, viruses and bacteria transmitted by vectors.

  • Carry and transmit an infectious pathogen into another living organisms.

  • Examples include: Malaria, Dengue, Chikungunya, Zika, West Nile Virus

• Zoonotic Diseases: Diseases/infections that are transmitted from vertebrate animals to humans-

  • Bacterial, viral, or parasitic.

  • Can spread through both direct contact or via food/water/environment.

  • Examples include: Rabies, Ebola, supposedly Covid-19

  • Not all vector-borne diseases are zoonotic and not all zoonotic diseases are vector-borne!

Modes of Transmission

• Anthroponoses:-

  • Direct transmission: humans to humans

  • Indirect transmission: human to vector human

• Zoonoses:-

  • Direct transmission: Animal to animal to human

  • Indirect: animal to vector to animal

Biodiversity

• The variety of all living organisms on the surface of the Earth.

• Present within + between species, as well as between + within ecosystems.

• Higher # of species à healthier ecosystem à positive outcomes for all on planet

Ecosystems

• A community of organisms together with their physical environment.

• 3 types: Marine (saltwater), Aquatic (freshwater), and Terrestrial.

• The higher biodiversity present, the more resilient they are in the face of disturbances.

Forests and Climate Change

• Forests act as both a source and sink for carbon.

Wetlands

• Canada is home to ~25% of the world’s wetlands!

• Store water from snow and rainfall, releasing it when things get dry.

• Serve as a food source and shelter for other species.

• Excellent recreation places.

The Water Cycle

• The sun evaporates water from the oceans into water vapor. This invisible vapor rises into the atmosphere, where the air is colder.

• The water vapor condenses into clouds.

• Volcanoes emit steam, which forms clouds.

• Air currents move clouds all around the Earth.

• Water drops form in clouds, and the drops then fall to Earth as precipitation (rain and snow).

• In cold climates, precipitation builds up as snow, ice, and glaciers.

• Rainfall on land flows downhill as runoff, providing water to lakes, rivers, and the oceans.

• Some rain soaks into the ground, as infiltration, and if deep enough, recharges groundwater.

• Snow can melt and become runoff, which flows into rivers, the oceans, and into the ground.

Effects of Climate Change on Water Availability

• Hotter/Drier Conditions (Interior West):-

  • Heat trapped by the atmosphere causes more evaporation and more precipitation.

  • Decreases in snowfall due to warming lead to proportional increases in rainfall.

  • Decrease in rainfall.

  • Decreased snowpack and glaciers.

  • More severe droughts.

• Hotter/Wetter Conditions (NE and Coasts):-

  • A warmer atmosphere holds more water vapor, which is also a heat-trapping gas.

  • Decrease in light rains.

  • Increase in rainfall from heavy precipitation events.

  • Leads to increased flooding and sediments.

  • Earlier peak streamflow.

• Changes Common to Both Regions:-

  • Increased water usage.

  • Reduction in runoff.

  • Increased severe droughts.

  • Decrease in late-summer water flow with increased water temperature.

Natural Systems & Food Production

• Agrochemicals (fertilizers & pesticides): Alter nutrient cycles, contaminate groundwater, contribute to smog, can cause direct toxicity.

• Conversion of land for agriculture and animals husbandry = primary driver of biodiversity loss, land degradation, and water scarcity.

Oceans

• Serve various roles: Climate regulation, Food provision, Carbon storage, Employment, Coastal protection, Marine life.

Ocean and Plastics

• Plastics in the ocean contribute to coastal pollution, sea life injury and death, sea life illness, and human illness.

Ocean Acidification

• Impacts seafood and mental health.

Pandemics

• Pandemics are not unprecedented.

Micro, Meso, & Macro Impacts

• Different levels of impacts.

Wicked Problem

• Critically examine what makes mental health and climate change a wicked problem.

Sustainable Development Goals

• The Sustainable Development Goals are a call for action by all countries to promote prosperity while protecting the planet.

• Focus on economic growth and address a range of social needs including education, health, social protection, and job opportunities, while tackling climate change and environmental protection.

• They address the global challenges: poverty, inequality, climate change, environmental degradation, peace and justice.

Top Risk Factors Associated with Climate Change

• Hazards.

• Who/what (region) is exposed to hazards.

• Level of vulnerability of exposed individuals and communities.

• Groups Vulnerable: less able, pregnant, already infirm, poor, displaced and homeless, children & elderly, athletes, outdoor & manual workers.

• Direct effects: storms, drought, flood, heatwaves.

• Indirect effects: water quality, air pollution, land use change, ecological change.

• Social dynamics: age and gender, health status, socioeconomic status, social capital, public health infrastructure, mobility and conflict status.

• Health impact: Mental illness, undernutrition, allergies, cardiovascular diseases, infectious diseases, injuries respiratory diseases, poisoning.

• Non-Communicable Disease: cardiovascular disease, cancer, diabetes, respiratory disease, mental health, gastrointestinal

• FAST : face, arms, speech, time.

• Airway with Asthma – inflammation and constriction.

• Higher metabolic rate = higher 02 demands = higher resting heart rate.

• Urbanization: change in demographics and land use patterns (lots of greenspace, more condensed living).

• Direct effects: PTSD, Acute Anxiety Disorder

• Indirect effects: aggression, violence & suicide; climate justice & migration; food, increased hospitalization, depression, eco-anxiety and ecological grief.

• Unbreathable air, wildfires, & respiratory health outcomes

• Invisible killer: air pollution (lung cancer, stroke, heart disease)

• Types of Air pollution:-

  • Ambient: Outdoor air pollution; fast developing low & middle-income countries -

    • Fossil fuel combustion

    • Burning of biomass

  • Household: cooking, heating, and lighting sources

• Sources of air pollution: industry & energy supply; dust, transport, waste management, dust agricultural practices, household energy

• Air pollutants: Ground level $O_3$: particulate matter, sulphur dioxide, nitrogen dioxide, carbon monoxide, aeroallergens

• Heat death plagues:-

  • Immediate health issues: dehydration, heat exhaustion, heat stroke, cardiac arrest

  • Longer-term health issues: kidney disease/kidney stones, renal failure

• Modes of Transmission of INFECTIOUS DISEASES-

  • Anthroponoses:-

    • Direct transmission: humans to humans

    • Indirect: human to vector human

  • Zoonoses:-

    • Direct transmission: Animal to animal to human

    • Indirect: animal to vector to animal

• Vector-borne diseases-

  • Carried and transmitted by vectors (mosquitoes, fleas, ticks)

  • Caused by parasites, viruses and bacteria

  • Carry and transmit an infectious pathogen into another living organisms

  • Ex. malaria, dengue

• Zoonotic diseases-

  • Diseases that are transmitted from vertebrate animals to humans