BY ASSOC PROF DR ROSLINA ABDUL RAHIM Physiologist , Kulliyyah of Medicine , International Islamic University Malaysia .

Fossil fuel combustion , driven by human activities and the Industrial Revolution , has resulted in elevated carbon dioxide levels . Methane , a potent greenhouse gas , is generated through decomposing landfills , agricultural waste , and the digestive processes of ruminant animals . Simultaneously , nitrogen oxide is produced by applying fertilisers and the combustion of fossil fuels and vegetation .

The escalation of carbon dioxide , methane , nitrogen oxides , and CFCs has intensified greenhouse gasses , trapping additional heat and contributing to the rise in Earth ’ s surface temperature . With an increase in temperature , more water vapour will evaporate from oceans and various water sources , leading to global warming .

THE THERMOREGULATION MECHANISM

The human body regulates its temperature through a process known as thermoregulation , where the system includes the hypothalamus , sweat glands , circulatory system , and skin . In response to exposure to hot temperatures , sweating becomes a fundamental means by which the body manages its temperature . The evaporation of sweat contributes to skin cooling .

In contrast , in exposure to cold weather , the skin blood flow decreases through vasoconstriction , reducing peripheral ( skin ) temperature and preserving the core temperature .

THREATS OF CLIMATE CHANGE TO MANKIND

Exposure to extremely high temperatures

caused heat-related illnesses and fatalities , especially among children , the elderly , individuals with chronic conditions , and those in impoverished communities . Additionally , workers in various sectors , including farming , construction , firefighting , mining , military service , and manufacturing , are at risk when operating in environments where heat is generated during processes .

Heat exhaustion is a serious condition that arises from prolonged exposure to extreme heat , often accompanied by dehydration . Symptoms of heat exhaustion include excessive sweating , fatigue , headaches , dizziness , irritability , nausea , vomiting , increased thirst , and decreased urination . Water and salt depletion due to excessive sweating also causes heat cramps associated with painful muscle spasms ( contractions ) in the abdomen , arms , and legs .

Heat stroke is the most serious heatrelated illness marked by the breakdown of the body ’ s thermoregulation system , leading to a core temperature surge to 41 ° C or beyond , necessitating immediate emergency intervention . Heat stroke happens suddenly and may be preceded by heat exhaustion and heat cramps . Symptoms include a markedly elevated body temperature ( exceeding 40 ° C ), hot , red , and either dry or moist skin , a fast and strong pulse , headaches , dizziness , nausea , confusion , and loss of consciousness .

Extreme heat can potentially harm tissues , disrupt cellular processes within the body , cause protein denaturation , and destabilise cellular membranes .

Extreme hot weather can also contribute to excessive aggressiveness , diminished energy levels , and reduced concentration ability . Moreover , numerous scientific studies have demonstrated a connection between extreme heat and mental health issues .

The consequences of fossil fuel combustion , air pollution , extreme heat , and intense weather patterns can both directly and indirectly escalate cardiovascular morbidity and mortality .

HEALTH OF ANIMALS CAN BE JEOPARDISED

This can further manifest in hemoconcentration and inflammation . In severe cases , heat stress may even lead to autonomic dysfunction .

The Million Hearts ® Climate Change and Cardiovascular Disease Collaborative ( CCC ) reported that heatwaves have the potential to heighten the likelihood of cardiovascular events such as heart attacks and strokes , especially among individuals already predisposed to these conditions .

The chemical interactions between nitrogen oxide and volatile organic compounds , originating from sources like car exhaust and wildfires , result in ozone formation . Inhaling ozone irritated and inflamed the lungs and the respiratory system , causing shortness of breath . Warmer weather is linked to stagnant air conditions , which means individuals may experience prolonged exposure to groundlevel ozone on hot days as the polluted air accumulates .

The prevalence of hospital admission

for conditions such as chronic obstructive pulmonary disease ( COPD ), pneumonia , asthma , allergies , and other lung diseases has increased with the surges in ground-level ozone . Warming temperatures additionally extend and intensify pollen seasons and foster the growth of fungi and indoor mould , which can exacerbate respiratory allergies , rhinitis , and asthma .

Global climate change has led to disruptions in food chain systems , which caused the crop yield and vegetation to drop , thus shrinking food supply . Other than that , soil erosion and increased carbon dioxide levels lead to changes in the nutrient content in food , thereby affecting the quality of food produced . The health and productivity of animals raised for meat , milk , and eggs were also jeopardised .

The increasing temperature and acidification of oceans are significantly disrupting aquatic ecosystems , which alters fish distribution and the productivity of marine and freshwater species . Elevated sea surface temperatures expedite the growth of waterborne pathogens along coastlines . Individuals consuming contaminated seafood may suffer from diarrhoea , septicemia , and even fatalities .

The restricted accessibility and affordability of nutritionally rich food might contribute to adopting unhealthy eating of ultra-processed foods , which are more affordable and available . These factors can contribute to communities experiencing malnutrition , resulting in the escalation of stunting children and the prevalence of noncommunicable diseases .

Dr Rohaida Ismail , a Public Health Expert from the Ministry of Health Malaysia , has disclosed that rising of the Earth ’ s temperature may heighten the risk of vector-borne diseases such as malaria and dengue fever . The warming climate extends the mosquito ’ s lifespan and breeding period , potentially expanding its habitat .

Mosquito biting activity intensifies within a temperature range of 26 C and 35 ° C . Additionally , elevated temperatures can expedite the dengue virus replication in Aedes aegypti mosquitoes , thereby shortening the virus ’ s transmission period .

ALLEVIATING THE IMPACT OF CLIMATE CHANGE

Raising public awareness within the community is imperative to mitigate the impact of climate change . The community can adopt various mitigation measures to alleviate the effects of climate change .

Consider reducing the frequency of car trips and practice carpooling when feasible . Choose to reuse takeaway coffee cups or opt for a travel mug .

Instead of using plastic shopping bags , consider utilising a reusable canvas bag . Adjust the water heater thermostat to a lower setting . Consistently clean and keep your air conditioners in good condition .

Turn off the lights when leaving a room , and conserve water by turning off the tap while brushing your teeth . Lastly , embrace the principles of reduce , reuse , and recycle whenever possible . – The HEALTH