Rain-triggered Landslides and IMD’s Monsoon Forecast
Rain-triggered Landslides and IMD’s Monsoon Forecast
- Landslides in Wayanad, Kerala:
- Over 200 people killed due to rain-triggered landslides.
- Heavy rainfall and subsequent landslides affected Wayanad severely.
- Rainfall in Uttarakhand and Himachal Pradesh:
- Intense rainfall spells causing disruptions and potential disasters.
- These regions often face similar monsoon-related challenges.
IMD Monsoon Forecast
- Overall Forecast:
- Above-normal rainfall forecasted for August and September.
- IMD predicts above 106% of the Long Period Average (LPA) for the second half of the monsoon.
- August and September:
- August expected to receive normal rainfall.
- September forecasted to receive more rainfall than the average 17 cm.
- Impact on Agriculture:
- Heavy rains in September can damage standing crops.
- Example: Soya bean crop damage in Madhya Pradesh due to heavy September rains two years ago.
La Niña Influence
- Development of La Niña:
- La Niña or La Niña-like conditions expected to develop by end of August.
- Likely to result in increased rainfall in September.
Regional Rainfall Data
- July Rainfall:
- July, the rainiest monsoon month, recorded 30.5 cm of rainfall, 9% more than normal.
- Surplus rainfall observed in all parts of the country except northeastern, eastern, and northwestern India.
- Heavy Rainfall Reports:
- 1,223 stations reported heavy or very heavy rainfall in July (defined as 11 cm or more).
Alerts and Preparedness
- IMD Alerts:
- Issued an orange alert for Kerala on July 29.
- Upgraded to a red alert on July 30 early morning.
- Orange alerts issued in advance for scattered intense rain in Delhi.
- Authority Actions:
- Orange alerts indicate preparatory actions for authorities.
- Red alerts signal immediate action to mitigate disaster impacts.
Environmental and Agricultural Implications
- Impact on Winter Sowing:
- Unusually heavy rain in September and October can disrupt winter sowing patterns.
- Potential to spike air pollution in northern India due to altered agricultural activities.
- Crisis Management and Response:
- Importance of timely alerts and preparatory measures.
- Role of state and local authorities in mitigating disaster impacts.
Preparation Tips
- Prelims Focus:
- Understand the IMD’s alert system and classifications (orange and red alerts).
- Basic concepts of La Niña and its impact on Indian monsoon patterns.
- Geographic impact of heavy rainfall on different Indian regions.
- Mains Focus:
- Analyze the socio-economic impact of heavy rains and landslides on affected regions.
- Discuss the implications of changing monsoon patterns on agriculture and food security.
- Evaluate the effectiveness of disaster preparedness and response mechanisms in India.
- Environmental impact of heavy monsoon rains on air quality and agricultural practices.
Quiz on Rain-triggered Landslides and IMD’s Monsoon Forecast
- What was the primary cause of the landslides in Wayanad, Kerala, that resulted in over 200 deaths?
- A) Earthquakes
- B) Heavy rain
- C) Deforestation
- D) Construction activities
- What does the India Meteorological Department (IMD) predict about the rainfall for August and September?
- A) Below normal rainfall
- B) Normal rainfall
- C) Above normal rainfall
- D) No significant change in rainfall
- Which climatic condition is expected to develop towards the end of August and influence increased rainfall in September, according to the IMD?
- A) El Niño
- B) La Niña
- C) Indian Ocean Dipole
- D) Arctic Oscillation
- In which month did the rainiest monsoon month occur, and what was the recorded rainfall according to the IMD data?
- A) June, 40 cm
- B) July, 30.5 cm
- C) August, 35 cm
- D) September, 20 cm
- What type of alert did the IMD issue for Kerala on July 29, and what does it signify?
- A) Yellow alert, signifies caution
- B) Red alert, signifies immediate action
- C) Orange alert, signifies preparatory action
- D) Green alert, signifies normal conditions
Answers and Explanations
- Answer: B) Heavy rain
- Explanation: The landslides in Wayanad, Kerala, were primarily triggered by heavy rain, which resulted in severe casualties and property damage. Rain-triggered landslides are common in hilly regions during the monsoon season.
- Answer: C) Above normal rainfall
- Explanation: The IMD predicts above-normal rainfall for August and September, forecasting more than 106% of the Long Period Average (LPA) for the second half of the monsoon season. This means that these months will likely experience higher-than-usual rainfall.
- Answer: B) La Niña
- Explanation: La Niña or La Niña-like conditions are expected to develop towards the end of August, which could lead to increased rainfall in September. La Niña typically results in cooler ocean temperatures in the central and eastern Pacific, influencing weather patterns globally.
- Answer: B) July, 30.5 cm
- Explanation: July, the rainiest monsoon month, recorded 30.5 cm of rainfall when averaged across the country. This was nearly 9% more than normal, indicating a particularly wet monsoon month.
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Answer: C) Orange alert, signifies preparatory action
- Explanation: The IMD issued an orange alert for Kerala on July 29, which signifies that authorities should take preparatory actions to mitigate the potential impact of heavy rainfall. An orange alert is a warning to prepare for potential severe weather conditions.