TAG: GS 3: ECOLOGY AND ENVIRONMENT
THE CONTEXT: The World Meteorological Organization’s (WMO) State of the Global Climate 2023 report reveals a disturbing trend of multiple climate records being shattered in the year.
EXPLANATION:
- From greenhouse gas levels to ocean heat content, various indicators have reached alarming highs, signaling the accelerating pace of climate change.
Temperature Records:
- Global Mean Temperature:
- 2023 marked the warmest year on record, with the global mean near-surface temperature surpassing the previous record holders by a significant margin.
- The temperature anomaly of 1.45 ± 0.12°C above the 1850-1900 average underscores the urgency of addressing climate change.
- La Nina to El Nino Transition:
- The rapid temperature rise from 2022 to 2023 can be attributed in part to the transition from La Nina to El Nino conditions.
- This shift in the Pacific climate pattern influenced global temperature dynamics, contributing to the record warmth observed in 2023.
Greenhouse Gas Levels:
- Record High Concentrations:
- Greenhouse gas concentrations, including carbon dioxide, methane, and nitrous oxide, reached unprecedented levels in 2022.
- The concentrations of these gases exceeded pre-industrial levels by significant margins, with methane and nitrous oxide experiencing notable increases, highlighting the intensification of anthropogenic activities contributing to climate change.
Oceanic Changes:
- Ocean Heat Content:
- The total amount of heat stored by the oceans reached record levels in 2023.
- Ocean warming trends, particularly in the top 2000 m layer, have accelerated over the past two decades, emphasizing the profound impact of climate change on marine ecosystems and global weather patterns.
- Sea Level Rise:
- The rate of sea-level rise surged to a record high since 1993, attributed to ongoing ocean warming and melting glaciers and ice sheets.
- Satellite observations reveal a doubling of the sea-level rise rate, underscoring the urgent need for mitigative measures to address the impacts of rising sea levels on coastal communities and ecosystems.
- Marine Heatwaves:
- Marine heatwaves, characterized by persistently warm ocean temperatures, affected a significant portion of the global ocean in 2023.
- The increased frequency and intensity of these events pose serious threats to marine biodiversity, fisheries, and ecosystem health.
- Ocean Acidification:
- The acidification of the ocean, driven by the absorption of anthropogenic carbon dioxide, has reached alarming levels.
- The decrease in pH levels poses risks to marine organisms and ecosystem services, highlighting the interconnectedness of climate change impacts across various domains.
Polar Ice Dynamics:
- Arctic and Antarctic Sea Ice:
- Both the Arctic and Antarctic regions experienced notable changes in sea ice extent in 2023.
- The Arctic Sea ice extent remained below normal, while the Antarctic sea ice extent reached a record low.
- These trends underscore the vulnerability of polar regions to the impacts of climate change.
Glacier Retreat:
- Global Glacier Mass Balance:
- Preliminary data indicate a significant loss in glacier mass in 2023, with negative mass balances observed across various regions.
- Glaciers in western North America and Europe experienced particularly severe losses, highlighting the accelerating pace of glacier retreat and its implications for water resources and sea-level rise.
World Meteorological Organization (WMO):
- It is a specialized agency of the United Nations (UN).
- It is the UN system’s authoritative voice on the state and behavior of the Earth’s atmosphere, its interaction with the oceans, the climate it produces, and the resulting distribution of water resources.
- It originated from the International Meteorological Organization (IMO), which was founded in 1873.
- Established in 1950, WMO became the specialized agency of the UN for meteorology (weather and climate), operational hydrology and related geophysical sciences.
- Its headquarters is in Geneva, Switzerland.
Greenhouse gas:
- A greenhouse gas (GHG) is a gas that absorbs and emits radiant energy at thermal infrared wavelengths, causing the greenhouse effect.
- The primary GHGs in Earth’s atmosphere are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and ozone (O3).
