What Made This Year's Monsoon Rains So Deadly in India?

India is currently experiencing an unprecedented monsoon season, with half the country battling severe flooding due to extraordinary rainfall. The Indian Meteorology Department has reported that states such as Punjab are facing their worst deluge since 1988, with some regions recording over 1,000% more rainfall than average within 24 hours. This article delves into the causes of this extreme weather, the implications of climate change, and the urgent need for adaptive measures.

Last updated: 03 October 2023 (BST)

Key Takeaways

• Extreme rainfall in India has led to widespread flooding, particularly in Punjab, Haryana, and Rajasthan.
• Climate change has resulted in increased moisture in the atmosphere, leading to intense downpours.
• The interaction between monsoon systems and westerly disturbances has caused unusual weather patterns.
• Melting glaciers and human activities exacerbate flooding risks in northern India.
• Immediate action is necessary to address infrastructure issues and mitigate flood impacts.

The Current Monsoon Crisis in India

As of late August and early September 2023, India has been grappling with a monsoon season that has taken a severe turn. The past week saw rainfall in northwest India soar to 180% above average, with southern regions experiencing a 73% increase. Such extraordinary levels of precipitation have led to devastating floods, landslides, and the loss of life across numerous states.

Understanding the Meteorological Factors

The Indian Meteorology Department (IMD) attributes this extreme weather primarily to a combination of high moisture levels in the atmosphere and specific meteorological phenomena. The monsoon, traditionally characterised by steady rainfall spread over four months, has evolved into a pattern of intense, localized downpours following prolonged dry spells.

One significant factor contributing to the current situation is the phenomenon known as a "cloudburst." This occurs when moisture-laden clouds collide with mountainous terrain, resulting in rapid, heavy rainfall in a concentrated area. Such events have wreaked havoc in the Himalayan states of Uttarakhand and Himachal Pradesh earlier this season.

The Role of Westerly Disturbances

In addition to cloudbursts, the interaction of the monsoon system with westerly disturbances has heightened the intensity of rainfall. These disturbances typically originate in the Mediterranean region and move eastward, bringing cold air that meets the warm, moist air of the monsoon. This clash can lead to severe weather events, as observed this year.

Research scientist Akshay Deoras explains this interaction as a rare "atmospheric tango," where the monsoon acts like a loaded water cannon, and the westerly disturbances serve as the trigger. This year, the disturbances have remained unusually far south, leading to unprecedented rainfall in northern India.

Climate Change and its Impact on Monsoon Patterns

Climate change is a significant factor altering monsoon behaviour. Scientists have noted an increase in atmospheric moisture levels due to warming oceans. The Indian Ocean and Arabian Sea are contributing more moisture to the air, intensifying rainfall events. Furthermore, global warming is influencing jet streams, causing them to become more erratic and wavier. This change affects weather systems worldwide, including the monsoon dynamics in India.

Consequences of Extreme Weather Events

The implications of intense rainfall extend beyond immediate flooding. In northern India, particularly downstream regions of the Himalayas, floods have occurred even without significant rainfall. Factors contributing to these events include:

• Overfilled glacial lakes bursting due to rapid melting.
• Underground lakes swelling and causing flash floods.
• Landslides blocking rivers and creating artificial lakes that eventually release water.

The Role of Glacial Melting and Human Impact

As glaciers melt rapidly due to rising temperatures, the stability of mountainous regions is compromised. The ice and snow that traditionally help hold mountain slopes steady are diminishing, leading to increased landslide risks and flooding. Geoscientist Jakob Steiner notes that rain falling on snowfields can cause rapid melting, resulting in floods that can devastate downstream areas.

Additionally, human activities exacerbate the situation. Urban development in floodplains and river pathways, combined with inadequate infrastructure, has left many regions vulnerable to flooding. The encroachment on natural waterways and the poor state of drainage systems have further complicated the already dire scenario.

Addressing the Challenges Ahead

Experts emphasise the urgent need for proactive measures to mitigate the impacts of extreme rainfall and flooding. Recommendations include:

• Repairing and upgrading river embankments and drainage systems.
• Implementing sustainable urban planning to avoid encroachments on flood-prone areas.
• Enhancing early warning systems for severe weather events.
• Promoting community awareness and preparedness for natural disasters.

What Does the Future Hold?

As the monsoon season continues, further heavy rainfall is forecast across large parts of India. This situation serves as a reminder of the urgent need to adapt to changing climate patterns and implement effective management strategies to reduce vulnerability to floods and landslides.

FAQs

What are the primary causes of the current floods in India?

The current floods in India are primarily caused by extreme rainfall due to climate change, the interaction of monsoon systems with westerly disturbances, and the rapid melting of glaciers leading to unstable mountain conditions.

How does climate change affect monsoon patterns in India?

Climate change increases atmospheric moisture and alters jet stream patterns, resulting in more intense, localized rainfall instead of steady precipitation over the monsoon season.

What is a cloudburst, and how does it contribute to flooding?

A cloudburst is a sudden and intense rainfall event that occurs when moisture-laden clouds collide with mountainous terrain, leading to rapid, heavy rainfall in a small area, which can cause flash floods.

How do human activities contribute to the flooding crisis?

Human activities, such as urban encroachment, inadequate infrastructure, and poor management of water systems, exacerbate flooding risks by blocking natural water flow and weakening flood defenses.

What measures can be taken to address flooding in India?

To address flooding, it is crucial to repair and upgrade drainage systems, implement sustainable urban planning, enhance early warning systems, and promote community awareness and preparedness for natural disasters.

The current monsoon crisis in India highlights the urgent need for collective action to mitigate the impacts of climate change and manage water resources effectively. As the weather patterns continue to shift, how prepared are we to face the challenges ahead? #Monsoon2023 #ClimateChange #FloodManagement