Rising Global Temperatures | 03 Jun 2024

Source: IE

Why in News?

The world is witnessing a concerning trend of record-breaking temperatures across the globe, exacerbated by global warming. From the scorching 56.7°C recorded in Death Valley, California over a century ago to the recent 52.9°C reading in Delhi, temperature extremes are becoming more prevalent as the planet continues to heat up.

• If the 52.9°C recorded at a station in Delhi is verified, it would be an all-time high for India.

What is the Historical Context of Global Temperature Records?

• Historical High: The highest temperature ever recorded on Earth was 56.7°C in Death Valley, California, in 1913.
  • United Kingdom: Surpassed 40°C for the first time in July 2022.
  • China: Recorded its highest temperature of 52°C in a northwestern town last year.
  • Europe: Sicily, Italy, reached 48.8°C in 2021, a record for the continent.
  • India: Rajasthan's Phalodi recorded the highest temperature of 51°C in 2016.
• Global Trends: An analysis shows nearly 40% of the Earth experienced its highest-ever daily temperature between 2013 and 2023.
  • This includes diverse regions, from Antarctica to various parts of Asia, Europe, and the Americas.
  • Global average temperatures are currently about 1.61°C higher than pre-industrial levels.

How Global Warming is Exacerbating Global Temperatures?

• Definition: Global warming refers to the long-term increase in Earth's average surface temperature due to human activities, primarily the emission of greenhouse gases (GHG) like carbon dioxide (CO₂) and methane (CH₄).
• Greenhouse Gases and Temperatures: GHGs trap heat in the Earth's atmosphere, preventing it from escaping into space.
  • Increased concentrations of these gasses enhance this effect, leading to more heat being retained and higher global temperatures.
• Global Temperature Rise: The planet's average surface temperature has risen about 1°C since the late 19^th century, a change driven largely by increased GHG emissions into the atmosphere and other human activities.
  • The past decade has seen many of the warmest years on record, with 2023 and 2024 showing unprecedented temperature increases.
  • The period from May 2023 to April 2024 was the warmest 12-month period, with global temperatures about 1.61°C above pre-industrial levels.
• India Compare to Global Warming Trends: India's warming is less than the global average.
  • Indian temperatures have increased by 0.7 degrees Celsius since 1900, while global land temperatures have risen by 1.59°C. When including oceans, global temperatures are now at least 1.1°C higher than pre-industrial levels.
• Global Warming and Heatwaves: Global warming is causing an increase in global temperatures and the frequency of heatwaves.
  • In India Heat waves typically occur from March to June, and in some rare cases, even extend till July. On an average, five-six heat wave events occur every year over the northern parts of the country.
  • Heatwaves in India are becoming more severe, with heatwave conditions even in February, a winter month for which heatwave thresholds are not defined.
    • The current high temperatures in Delhi and North India seem abnormal compared to the average temperatures from 1981-2010.
    • In the future, temperatures of 45°C and above may become the new normal, and a reading of 50°C will no longer be seen as unusual.
• Geographical Variability: Global warming is not causing a uniform rise in temperatures everywhere. Some regions experience faster warming due to factors like:
  • Polar Amplification: The Arctic and other polar areas are warming much faster due to melting sea ice and permafrost.
  • Land vs Water: Land warms faster than oceans, so continental interiors warm faster than coastal regions.
  • Elevation: Higher elevations experience slower warming as the atmosphere traps less heat.
  • Ocean Currents: Regions influenced by warm currents like the Gulf Stream warm faster.
  • Landlocked Countries: Landlocked areas have less evaporative cooling and the continental effect, leading to more extreme temperature swings.
• Urban Heat Islands (UHIs): UHIs are metropolitan areas significantly warmer than surrounding regions due to heat-absorbing surfaces and energy use.
  • As global temperatures rise, UHI intensity is expected to increase, amplifying heatwaves in cities.
  • The higher urban temperatures also drive greater fossil fuel-powered cooling, further contributing to GHG emissions and warming.
  • Populations in UHIs are especially vulnerable to the health risks posed by the compounded effects of UHIs and climate change.

What are the Consequences of Rising Global Temperatures?

• Sea Level Rise: As temperatures rise, glaciers and ice sheets melt, adding water to the oceans and causing sea levels to rise. This inundates coastal areas, displaces communities, and disrupts ecosystems.
  • Global sea level has risen by about 8 inches since 1880 and is projected to rise by at least another foot by 2100. In a high-emissions scenario, it could potentially rise as high as 6.6 feet.
• Ocean Acidification: The oceans absorb a significant amount of the CO2 released into the atmosphere. This makes the oceans more acidic, harming marine life and disrupting ocean ecosystems crucial for the health of the planet.
  • Hurricanes are expected to become stronger and more intense as the climate warms, leading to increased storm intensity and rainfall rates.
• Droughts and Heat Waves: Droughts and heat waves are expected to become more intense, while cold waves are expected to become less intense and less frequent.
• Wildfire Season: Wildfire season has been prolonged and intensified due to warming temperatures and long-term drought, increasing the risk of fires.
  • Human-caused climate change has already doubled the area of forest burned and is projected to further increase the amount of land consumed by wildfires in Western states by around 2050.
• Biodiversity Loss: Rising temperatures and changing weather patterns disrupt ecosystems and habitats, pushing many plant and animal species towards extinction.
• Climate change: Extreme weather disrupts food production, leading to shortages and price hikes that harm vulnerable populations.
  • Rising temperatures worsen air quality, increase heat-related illnesses, and facilitate disease spread.
  • The economic consequences are severe, with high costs for repairing infrastructure, declining agricultural yields, and escalating disaster relief.

Way Forward

• Six-Sector Solution: Follow the United Nations Environment Programme’s roadmap, which includes reducing emissions across sectors like energy, industry, agriculture, forests, transport, and buildings.
• Carbon Offsetting: Invest in projects that draw down carbon from the atmosphere, such as reforestation or carbon capture and storage.
• Reduction in Greenhouse Gas Emissions: Transition to renewable energy sources like Solar, wind, geothermal, and hydro power can significantly reduce our dependence on fossil fuels.
  • Implementing energy-efficient practices in homes, industries, and transportation can drastically cut down on energy consumption.
• Sustainable Agriculture: Adopt climate-smart agricultural practices, such as sustainable irrigation techniques, drought-resistant crop varieties, and agroforestry.
  • Enhance food storage and distribution systems to minimise losses and ensure access to food during extreme weather events.
  • Reducing deforestation, utilising regenerative agriculture techniques, and promoting plant-based diets can all contribute.
• Support Climate-Vulnerable Populations: Assist communities most vulnerable to climate change impacts, such as those in low-lying coastal areas and developing countries.