Context: Last weekend, parts of North India witnessed heavy rains that triggered flash floods and left a trail of destruction, tragically it resulted in at least 50 reported deaths. Himachal Pradesh was the worst affected. Several places in Haryana, Punjab and Himachal Pradesh reported record rainfall.
Urban Flooding In India
Urban flooding occurs when rainfall exceeds the capacity of drainage systems, such as sanitary sewers, and floods land or property within a developed environment, especially in more densely populated places. It occurs regardless of whether affected communities are located within designated floodplains or near any body of water.
Factors attributed to the Heavy Downpour in north India
- Active Monsoon and Moisture Influx: An active monsoon season with strong winds in the lower air layers brought in moisture from the Bay of Bengal and the Arabian Sea. These moisture-laden winds contributed to the heavy rainfall in the region.
- Atmospheric Forcing and Eastward Moving Troughs: Large-scale atmospheric forcing, in the form of outflows in the upper layers of the atmosphere, moved eastward through mid-latitude troughs. These troughs directed the flow of moisture towards the Himalayan region, exacerbating the intensity of the rainfall.
- Orographic Uplift and Steep Terrain: The steep terrain of the Himalayas, combined with orographic uplift, played a significant role in intensifying the precipitation. When air masses encounter the mountains, they are forced to rise, resulting in enhanced rainfall.
- Synoptic Conditions and Moisture Intrusion: The synoptic conditions during the period were conducive to heavy rainfall. The monsoon was active, with strong moist easterly winds entering the region. Additionally, there was moisture intrusion from the North Arabian Sea, further augmenting the rainfall.
Impact of Arctic Warming on Monsoon Climate
- Increased Frequency of Blocking Highs and Mid-latitude Troughs: Arctic warming has been observed to influence the monsoon climate through changes in mid-latitude circulation. As the Arctic warms and sea ice recedes, there is growing evidence of an increased frequency of blocking highs and deep mid-latitude troughs. These atmospheric patterns can affect weather systems and contribute to extreme rainfall events during the monsoon season.
- Influence on Circulation Patterns: Observations and models suggest that Arctic warming can alter circulation patterns, including the movement of air masses, pressure systems, and wind patterns. These changes can have cascading effects on the monsoon climate, including the transport of moisture and atmospheric conditions that contribute to heavy rainfall events.
- Impact on Monsoon Dynamics: The warming of the Arctic and subsequent changes in circulation patterns can affect the dynamics of the monsoon. This can lead to shifts in moisture inflow, atmospheric stability, and the timing and intensity of rainfall during the monsoon season.
- Potential for Future Changes: As Arctic warming continues; it is expected that the impacts on the monsoon climate will persist and potentially intensify. This suggests that the influence of Arctic warming on the monsoon may contribute to further changes in extreme precipitation patterns and associated impacts in the future.
Implications of Heavy Rainfall in India?
- Agriculture:
- Heavy rainfall and floods can damage crops, soil fertility, irrigation infrastructure and livestock.
- They can also affect crop sowing, harvesting, storage and distribution.
- This can lead to food insecurity, malnutrition, poverty and distress migration among farmers.
- Water resources:
- Heavy rainfall and floods can replenish groundwater, surface water and soil moisture levels.
- They can also improve water quality by flushing out pollutants.
- It can also cause waterlogging, erosion, sedimentation, landslides, dam breaches and contamination of water sources.
- lead to water scarcity, water conflicts, waterborne diseases and displacement of people.
- Energy:
- Heavy rainfall and floods can increase hydropower generation by increasing river flows and reservoir levels.
- They can also reduce thermal power generation by affecting coal supply and cooling systems.
- However, they can also damage power plants, transmission lines, substations and distribution networks.
- This can lead to power outages, blackouts, losses and accidents.
- Transportation:
- Heavy rainfall and floods can improve navigation by increasing water levels in rivers and lakes.
- However, they can also disrupt road, rail, air and water transport by causing landslides, floods, traffic jams, delays, cancellations, accidents and fatalities.
- Health:
- Heavy rainfall and floods can reduce air pollution by washing away dust particles and aerosols.
- They can also reduce heat stress by lowering temperatures and humidity.
- However, they can also increase vector-borne diseases.
Flood Management in India
- Every year, different parts of the country experience floods of varying magnitudes.
- Both the Union and State governments have prioritized flood management.
- Controlling floods has consistently been a key focus for the government.
Authorities
The India Meteorological Department (IMD) offers rainfall or cyclonic event forecasts that are used by all agencies to plan for floods.
National Disaster Management Authority (NDMA):
- NDRF collaborates with state equivalents for relief and rescue operations.
- NIDM reports to the Union Ministry of Home Affairs.
- NDMA reports to the Prime Minister’s Office.
- The Central Water Commission (CWC) collects hydrology data nationwide.
- CWC measures river discharge and water levels in dams.
- The data helps to warn states about potential flooding.
FAQs Related with Monsoon-battered North India
Ques 1: What are the lessons learned from the monsoon-battered North India?
Answer: The lessons learned from the monsoon-battered North India include the importance of robust infrastructure, early warning systems, and efficient disaster management protocols.
Ques 2: How can robust infrastructure help in dealing with monsoon-related challenges?
Answer: Robust infrastructure, including well-designed drainage systems and flood-resistant structures, can help mitigate the impact of heavy rainfall and prevent flooding in vulnerable areas.
Ques 3: What role do early warning systems play in managing monsoon-related disasters?
Answer: Early warning systems provide timely information about weather patterns, rainfall levels, and potential flood risks. They enable authorities to issue alerts, evacuate residents in vulnerable areas, and take necessary preventive measures to minimize damage.
Lesson Learnt from monsoon-battered North India
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