Climate Change Impacts

Climate change is the long-term alteration of global or regional climate patterns, primarily caused by human activities—most notably the burning of fossil fuels, deforestation, and industrial emissions. These activities increase the concentration of greenhouse gases (GHGs) in the atmosphere, which trap heat and drive global warming. As a result, Earth’s climate system is undergoing rapid and destabilizing changes that affect all aspects of life on the planet¹.

1. Rising Temperatures and Extreme Heat

Since the late 19th century, Earth’s average surface temperature has increased by approximately 1.1°C. This may seem small, but even fractional increases in temperature significantly alter weather systems and global energy balances². The past decade (2014–2023) was the hottest on record, and 2023 was the single warmest year globally³. Heatwaves are becoming more frequent, longer in duration, and more intense. In some parts of the world, temperatures now regularly exceed 50°C, leading to fatal consequences for humans, livestock, and crops⁴.

This warming trend has direct health implications: extreme heat increases the risk of dehydration, cardiovascular failure, and heatstroke. In urban areas, the “urban heat island effect” intensifies these risks, especially for vulnerable populations like the elderly, children, and those with pre-existing health conditions⁵.

2. Sea-Level Rise and Melting Ice

Melting glaciers, ice sheets, and the thermal expansion of seawater have led to a global average sea-level rise of approximately 20 cm since 1900, with the rate accelerating in recent decades⁶. Coastal cities such as Jakarta, Bangkok, and New York are experiencing more frequent tidal flooding. Low-lying island nations in the Pacific and Indian Oceans, such as Kiribati and the Maldives, are at risk of becoming uninhabitable due to saltwater intrusion and land loss⁷.

The Greenland and Antarctic ice sheets are melting at unprecedented rates, contributing significantly to sea-level rise. If these trends continue, projections suggest that global sea levels could rise by over 1 meter by the end of the century⁸.

3. Extreme Weather Events

Climate change is intensifying the frequency and severity of extreme weather events:

• Hurricanes and cyclones are gaining strength due to warmer ocean waters, with increased rainfall and storm surges causing massive destruction⁹.

• Floods are becoming more severe in regions where precipitation is intensifying.

• Droughts are prolonged and widespread in arid and semi-arid areas, with cascading impacts on agriculture, water availability, and fire risk¹⁰.

• Wildfires are growing in scale and intensity due to hotter, drier conditions in regions such as California, Australia, the Mediterranean, and Siberia¹¹.In each case, the link between a warming climate and disaster intensity is well-established. The increased energy in the atmosphere and oceans amplifies natural variability, leading to more destructive events¹².

In each case, the link between a warming climate and disaster intensity is well-established. The increased energy in the atmosphere and oceans amplifies natural variability, leading to more destructive events¹².

4. Biodiversity Loss and Ecosystem Disruption

Changing temperatures, altered rainfall patterns, and ocean acidification are profoundly disrupting ecosystems:

• Coral reefs, which support a quarter of marine biodiversity, are undergoing mass bleaching events due to warmer waters. Some regions have lost over 90% of their reef cover¹³.

• Species migration is shifting toward poles or higher elevations, threatening species that cannot adapt quickly enough. Some are going extinct before adaptation is possible¹⁴.

• Forests face heightened pest invasions, drought-related tree mortality, and increased fire frequency.

The loss of biodiversity undermines the stability and functionality of ecosystems. This affects essential services such as pollination, water filtration, and carbon storage—functions critical for human well-being and climate regulation¹⁵.

5. Impacts on Food Security and Water

Crop yields are declining in many parts of the world, particularly in tropical and subtropical regions. Heat stress reduces productivity in staple crops such as maize, rice, and wheat. In some African countries, maize yields have dropped by up to 30% due to rising temperatures and erratic rainfall patterns¹⁶. Simultaneously, water scarcity is worsening: nearly 4 billion people experience water shortages at least one month per year, and this figure is projected to increase as snowpacks decline and precipitation shifts¹⁷.

Irrigation systems and food supply chains are also at risk from both drought and floods, creating a volatile agricultural environment that threatens livelihoods and global food security.

6. Economic and Social Inequality

The economic costs of climate change are rising. Damages from climate-related disasters were estimated at over $360 billion globally in 2022 alone¹⁸. Insurance premiums are rising, particularly in flood- and fire-prone regions. The tourism industry, fisheries, and agriculture sectors—all climate-sensitive—face long-term losses. However, the burden is not equally distributed: lower-income countries and communities, which contribute least to emissions, are the most vulnerable to its effects¹⁹.

Climate change deepens inequality, displacing millions, straining public health systems, and exacerbating poverty. Climate-induced migration is increasing, as people flee areas made uninhabitable by drought, floods, or sea-level rise²⁰.

Conclusion

Climate change is not a distant or abstract threat—it is a current, measurable reality with cascading impacts on health, food, water, ecosystems, and economies. As the IPCC stresses, every fraction of a degree of warming avoided reduces these risks. Urgent action to reduce emissions and adapt systems to changing conditions is critical to safeguard both present and future generations.

Footnotes

1. IPCC. (2023). Climate Change 2023: Synthesis Report. Intergovernmental Panel on Climate Change.
2. NASA. (2024). Global Temperature Time Series. https://climate.nasa.gov
3. WMO. (2024). State of the Global Climate 2023. https://library.wmo.int
4. WHO. (2021). Climate change and health. https://www.who.int/news-room/fact-sheets/detail/climate-change-and-health
5. EPA. (2023). Urban Heat Islands. https://www.epa.gov/heatislands
6. IPCC. (2023). Sea Level Rise Fact Sheet. https://www.ipcc.ch
7. United Nations. (2021). Rising seas threaten island nations. https://www.un.org
8. NOAA. (2022). Sea Level Rise Projections. https://www.noaa.gov
9. IPCC. (2021). Extreme Weather Events in a Changing Climate. https://www.ipcc.ch
10. FAO. (2020). The State of Food Security and Nutrition in the World. https://www.fao.org
11. UNEP. (2022). Wildfires and Climate Change. https://www.unep.org
12. NASA Earth Observatory. (2023). Climate and Extreme Weather. https://earthobservatory.nasa.gov
13. NOAA. (2023). Coral Reef Watch. https://coralreefwatch.noaa.gov
14. WWF. (2022). Living Planet Report 2022. https://www.wwf.org.uk
15. IPBES. (2019). Biodiversity and Ecosystem Services Global Assessment. https://ipbes.net
16. CGIAR. (2021). Climate Change and Food Systems. https://www.cgiar.org
17. UNESCO. (2022). World Water Development Report. https://www.unesco.org
18. Swiss Re Institute. (2023). Natural Catastrophes: Global Losses. https://www.swissre.com
19. UNFCCC. (2023). Climate Justice. https://unfccc.int
20. IOM. (2021). Climate Migration and Displacement. https://www.iom.int

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