WARMEST NOVEMBER – environment

WARMEST NOVEMBER – environment

News: India recorded its second warmest November since 1901, underscoring a clear warming trend influenced by climate change.

WHAT’S IN THE NEWS?

  1. Second Warmest November in 123 Years:
    • The average maximum temperature was 29.37ºC, which is 0.62ºC above the normal of 28.75ºC.
    • The average minimum temperature stood at 16.91ºC, 1.05ºC higher than the typical 15.86ºC for November.
  2. Severe Rainfall Deficiency:
    • The country received only 13.5 mm of rainfall, which was 55% below the long-period average (LPA) of 29.7 mm.
    • The northwest region of India faced the worst rainfall deficit, experiencing a staggering 79.87% less precipitation than normal.
  3. Key Contributing Factors:
    • Weak western disturbances, which are critical for bringing cooler air and precipitation during this period, were largely absent.
    • Only two low-pressure systems formed in the Bay of Bengal, and Cyclone Fengal, which developed, failed to bring significant rainfall.
    • These combined factors extended the dry spell and led to November's overall warmer and drier conditions.

Role of Western Disturbances in India's Climate

  1. Definition and Characteristics:
    • Western disturbances are cyclonic weather systems originating over the Mediterranean Sea, Caspian Sea, and Black Sea.
    • These disturbances are carried eastward by subtropical westerly jet streams and impact the Indian subcontinent.
    • Classified as extra-tropical cyclones, they bring non-monsoonal precipitation in the form of rain and snow during winter.
  2. Significance of Western Disturbances:
    • Crucial for winter rainfall and snowfall, particularly in northwestern India, Pakistan, and Afghanistan.
    • Essential for Rabi crops such as wheat, mustard, and gram, which rely on winter precipitation for optimal growth.
    • Contribute approximately 30% of winter precipitation in regions like Jammu & Kashmir, Ladakh, Himachal Pradesh, Punjab, and Uttarakhand.
  3. Hydrological and Ecological Benefits:
    • The snowfall brought by western disturbances sustains snowpacks and glaciers, which feed perennial rivers critical for irrigation and drinking water needs.
    • Snow accumulation at higher elevations in sub-zero conditions delays melting, ensuring a steady water supply during drier months.
    • The albedo effect of snow in the Himalayas and Tibetan Plateau influences regional climate, including the onset of the Indian summer monsoon.
  4. Adverse Impacts of Strong Disturbances:
    • Intense western disturbances can trigger dense fog and cold waves in the northern plains, disrupting daily life.
    • They may also cause heavy snowfall, hailstorms, crop damage, landslides, and avalanches in mountainous regions, increasing risks to communities.

Global Context of November 2024’s Warming

  1. Global Temperature Anomalies:
    • Globally, November 2024 was the second warmest November on record, with an average temperature of 14.10ºC, which is 0.73ºC above the monthly average.
    • This aligns with predictions that 2024 could become the hottest year ever recorded globally.
  2. Declining Sea Ice Levels:
    • Antarctic sea ice extent reached its lowest level for November, measuring 10% below the long-term average.
    • Arctic sea ice extent also declined significantly, marking its third-lowest coverage for November, with an extent 9% below average.

Implications for India

  1. Impact on Agriculture:
    • The reduced winter rainfall and lack of cold weather conditions due to weak western disturbances pose a significant threat to Rabi crops.
    • Staple crops such as wheat, mustard, and gram, particularly in Punjab, Haryana, and Uttar Pradesh, face disruptions in growth cycles, risking lower yields and threatening food security.
  2. Ecosystem and Hydrological Risks:
    • The decline in seasonal snow cover and glaciers impacts water resources that are vital for irrigation, drinking water, and energy generation.
    • These changes can lead to reduced flow in perennial rivers, exacerbating water scarcity in downstream communities.
    • The warming trend increases the likelihood of extreme climatic events, further destabilizing ecosystems and biodiversity.
  3. Broader Climate Implications:
    • India’s warm November reflects global warming patterns, signifying a shift in regional and global climatic systems.
    • Such warming events could intensify the frequency and severity of extreme weather, including droughts, heatwaves, and storms.

Call to Action

  1. Urgency to Combat Climate Change:
    • The warm November of 2024 highlights the pressing need for collective global efforts to mitigate climate change and its cascading impacts.
    • Policy measures must focus on reducing greenhouse gas emissions, adopting sustainable practices, and enhancing renewable energy use.
  2. Protecting Ecosystems and Food Security:
    • Initiatives to safeguard biodiversity, protect agricultural productivity, and ensure water security are critical to adapting to changing climate patterns.
    • Building climate-resilient infrastructure and advancing early-warning systems can help communities adapt to increasing extreme weather events.

Source: https://indianexpress.com/article/upsc-current-affairs/upsc-essentials/what-the-warmer-november-of-2024-means-for-india-and-the-world-9753541/