Climate Change and Health

Climate & Health Nexus - The Unholy Alliance

• Climate change (↑ GHGs: $CO_2$, $CH_4$) impacts health: direct & indirect pathways.
• Key Pathways:
  • Direct: Extreme weather (heatwaves, floods) → heatstroke, injuries, displacement.
  • Indirect (Ecosystem): ↑ Vector-borne (dengue, malaria), water-borne (cholera); food insecurity.
  • Indirect (Social): Mental health impacts, conflicts.
• Vulnerable populations: Elderly, children, poor.

⭐ Climate change: a major health threat multiplier, worsening existing vulnerabilities.

Direct Health Impacts - Weathering the Storms

• Extreme Heat (Heatwaves):
  • Heat exhaustion, heat stroke (core temp > 40°C / 104°F, altered mental status).
  • Dehydration, electrolyte imbalance, acute kidney injury (AKI).
  • ↑ Exacerbation of cardiovascular, respiratory, renal diseases.
  • Vulnerable: Elderly, infants, pregnant women, chronic illness, outdoor workers.
• Floods & Heavy Rainfall:
  • Physical injuries (lacerations, fractures), drowning.
  • Water-borne diseases: Cholera, typhoid, leptospirosis, Hepatitis A/E. 📌 Leptospirosis risk ↑ wading floodwaters.
  • Vector-borne (post-flood stagnation): Malaria, dengue, chikungunya.
  • Mental health: PTSD, anxiety, depression.
  • Landslides (secondary to rain): Trauma, burial, asphyxiation.
• Cyclones/Storms (e.g., Hurricanes, Typhoons):
  • Major trauma (crush, penetrating), drowning.
  • Wound infections, tetanus, aspiration pneumonia.
  • Health service disruption (power loss, damage).
• Droughts & Wildfires:
  • Droughts: Malnutrition, ↑diarrheal diseases, mental stress.
  • Wildfires: Burns, respiratory illness (smoke), eye irritation, CO poisoning.

⭐ Heat stroke, a life-threatening medical emergency, is defined by a core body temperature exceeding 40°C along with central nervous system dysfunction (e.g., delirium, coma).

Indirect Effects & At-Risk Groups - The Ripple Effect

• Indirect Health Impacts (Mediated via Environment/Systems):

  • Water-borne diseases: ↑ incidence (Cholera, Typhoid) due to floods, contamination.
  • Vector-borne diseases (VBDs): Altered distribution & seasonality (Malaria, Dengue, Chikungunya, JE).
  • Food security: ↓ Crop yields → malnutrition, stunting.
  • Air quality: ↑ Respiratory illnesses (asthma, allergies) from wildfires, dust.
  • Mental health: Anxiety, depression, PTSD (eco-anxiety, displacement stress).
  • Displacement & conflict: Due to resource scarcity, extreme weather.

• Key At-Risk Groups (Increased Vulnerability):

  • Children & Elderly: Physiological susceptibility.
  • Pregnant Women: Risks to maternal & fetal health.
  • Low-Income Communities: Limited adaptive capacity, higher exposure.
  • Outdoor Workers (e.g., farmers): Direct exposure to heat, vectors, pollution.
  • Individuals with Pre-existing Conditions: (esp. respiratory, cardiovascular, mental health).
  • Coastal & Indigenous Populations: High environmental dependency & exposure.

⭐ Climate change is projected to cause an additional ~250,000 deaths per year between 2030 and 2050 from malnutrition, malaria, diarrhoea, and heat stress (WHO).

Mitigation & India's Stand - Healing Our Home

• Mitigation: Actions to ↓ GHG emissions & enhance sinks.
  • Key sectors: Energy (renewables, efficiency), transport (EVs, public), industry, AFOLU (Agriculture, Forestry, Other Land Use).
  • Examples: Afforestation, sustainable land management.
• India's Climate Action:
  • NAPCC (2008): 8 missions (Solar, Energy Efficiency, Water, etc.).
  • Panchamrit (COP26 Targets):
    • 500 GW non-fossil energy capacity by 2030.
    • 50% energy from renewables by 2030.
    • ↓ CO2 emissions by 1 billion tonnes by 2030.
    • ↓ Carbon intensity of economy by < 45% by 2030 (vs 2005).
    • Achieve Net Zero emissions by 2070.
  • International Solar Alliance (ISA) HQ: Gurugram, India.

⭐ India's Net Zero emission target year is 2070, announced at COP26 (Glasgow).

High‑Yield Points - ⚡ Biggest Takeaways

• Climate change ↑ heat stress, cardiovascular, and respiratory diseases.
• Altered vector ecology ↑ risk of vector-borne diseases (e.g., malaria, dengue).
• Impacts on food security and water availability lead to malnutrition.
• Extreme weather events (floods, droughts) cause injuries, displacement, mental health issues.
• Air pollution, often linked to climate drivers, worsens respiratory conditions.
• Vulnerable groups include the elderly, children, the poor, and those with pre-existing conditions.
• Key strategies: Mitigation (reducing emissions) and Adaptation (adjusting to impacts).