Context

A recent study revealed that Summer 2023 was the hottest season in the northern hemisphere in the past 2,000 years.

The Summer of 2023 Was the Hottest in 2000 Years Key Findings of the Study

• Significant Temperature Rise in 2023: The report indicates that the summer months of June, July, and August in 2023 experienced temperatures that were at least 0.5°C higher than any previously recorded extremes. 
  • The summer temperatures over northern hemisphere land areas were 2.07°C higher than during the pre-industrial period of 1850-1900. This rise significantly surpasses the Paris Agreement’s target to limit global temperature increases to below 1.5°C.
• Influence of El Niño: The intense heat experienced last year was partly due to the El Niño climate pattern, which is known to cause warmer global temperatures. It resulted into extended periods of drought, affecting various regions globally.
• Human Casualties: Heatwaves have had a severe impact on public health, with over 150,000 deaths annually linked to heat waves across 43 countries between 1990 and 2019. 
• Historical Climate Comparison: Researchers utilized tree-ring data to estimate global temperatures from the first century AD up to 1850. 
  • The findings revealed that 25 of the last 28 years have seen summer temperatures that surpass those of AD 246, which was the hottest year recorded before modern temperature records began. 
  • Additionally, the report noted that the coolest summer within the past 2,000 years was nearly four degrees cooler than the summer of 2023, influenced significantly by a major volcanic eruption.
• Urgency in Addressing Climate Change: The study emphasizes the critical need for immediate action in reducing emissions to control rising temperatures. Delaying action will only make the process more difficult and costly, according to the researchers.

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Health Risks Due to Increasing Temperatures

• Exposure of Elderly Populations: 
  • Current Risk: 14% of elderly people are currently exposed to temperatures exceeding 37.5°C, exacerbating health conditions and increasing mortality rates.
  • Future Risk: By 2050, this figure is expected to rise to 23%, exposing tens of millions more older people to dangerous heat extremes.
• Regional Disparities in Adaptive Capacity
  • Prepared Regions: Europe, despite being one of the fastest-warming areas, has systems in place to support people during heatwaves.
  • Vulnerable Regions: Africa and Asia have rapidly growing elderly populations but lack sufficient access to clean water and healthcare, making it difficult to cope with extreme heat.

Reason for Summer of 2023 Was the Hottest in 2000 Years

• El Niño Phenomenon: The El Niño climate pattern, which emerged in mid-2023, significantly contributed to the year’s extreme temperatures. 
• Rising Ocean Temperatures: Ocean temperatures have been increasing due to the absorption of heat trapped by greenhouse gasses. The oceans, acting as a heat reservoir, released more heat into the atmosphere, contributing to the overall temperature rise.
• Decrease in Aerosols: Aerosols, which can have a cooling effect by reflecting sunlight, have decreased due to air quality regulations. This reduction has diminished their cooling impact, allowing more heat to be retained in the atmosphere.
• Greenhouse Gas Emissions: The continuous increase in greenhouse gas emissions has been a long-term driver of global warming. These gasses trap heat in the atmosphere, leading to higher temperatures.
• Anthropogenic causes: Man made factors such as deforestation, faulty land use patterns, use of fossil fuels etc. have further contributed to temperature rise.