July 21st Current Affairs
UPSC Current Affairs – August 02nd
August 02nd Current Affairs Home / Table of Contents Counter‑terror operations in Jammu & Kashmir Context On August 2, 2025, security forces in Jammu & Kashmir’s Kulgam district launched Operation Akhal, a joint cordon-and-search mission by Indian Army’s Chinar Corps, J&K Police, and CRPF in the Akhal forest, based on specific intelligence.
UPSC Current Affairs – August 01st
August 01st Current Affairs Home / Table of Contents SC Deadline to Telangana Speaker on BRS MLAs’ Disqualification Context The Supreme Court on July 31, 2025, directed the Telangana Assembly Speaker to decide within 3 months on the disqualification petitions against BRS MLAs who defected to the Congress. The Court
UPSC Current Affairs – July 31st
July 31st Current Affairs Home / Table of Contents Missing Women and Girls in Madhya Pradesh Context Recent revelations in the Madhya Pradesh Vidhan Sabha have sparked concern over the disappearance of over 23,000 women and girls in the state, missing for more than a month and up to 1.5
UPSC Current Affairs – July 30th
July 30th Current Affairs Home / Table of Contents Australia Bans YouTube for Under-16s Context Australia has announced a comprehensive ban on YouTube for users under 16, extending existing restrictions on social media platforms like TikTok, Instagram, and Snapchat. The law will take effect from December 2025, imposing steep fines
UPSC Current Affairs – July 29th
July 29th Current Affairs Home / Table of Contents Monsoon’s Strong Performance Uplifts Kharif Prospects Context As of July 28, 2025, India has recorded an all-India rainfall of 440.1 mm since June 1—8% above normal. While most regions enjoyed normal to above-normal rainfall, eastern and northeastern India faced significant deficiencies,
UPSC Current Affairs – July 28th
July 28th Current Affairs Home / Table of Contents The Indian Textile Sector under Make in India Context India’s textile and apparel sector is undergoing a significant transformation under the Make in India initiative. With growing exports, robust policy support, and infrastructure development such as PM MITRA Parks, India is
Alaska Earthquakes
Why in News?
- On July 21, 2025, Alaska Peninsula was struck by a magnitude 6.2 earthquake at a shallow depth of 48 km—hours after a larger M 7.3 quake on July 17, which occurred at 36 km depth and triggered a tsunami warning
- Both quakes were followed by alerts due to heightened aftershock and tsunami risks.
Context
- Alaska sits on the Aleutian subduction zone, where the Pacific Plate dives under the North American Plate—making it among the earth’s most seismically active regions.
- Shallow quakes (<70 km) are more destructive due to stronger ground shaking
Past Instances
- Historical mega-earthquakes:
- 1964 magnitude 9.2 quake caused a colossal tsunami across the Pacific, killing ~130 in Alaska and Hawaii
- 1958 Lituya Bay quake (7.8–8.3 M) triggered a “megatsunami” wave over 500 m high
Global Response
- Tsunami warnings were issued post-7.3 quake; evacuations were precautionary and later downgraded after low wave activity.
- U.S. alerts leverage sirens, media, and door-to-door outreach—as practiced during the 1964 disaster—highlighting effective systems despite warning fatigue.
Implications
- Frequent shallow quakes stress the need for robust seismic monitoring, reliable tsunami procedures, and sustained public awareness.
- Warning fatigue is a concern: communities with regular false alarms may become complacent.
Earthquake Vulnerability in India
- Regions like Himalayan foothills and Andaman-Nicobar subduction zone remain highly vulnerable, notably during events like the 2004 tsunami.
NDMA Guidelines
- NDMA emphasizes:
- Seismic zoning and mapping of vulnerable coastal districts.
- Comprehensive early warning systems ( tide gauges, buoys, INCOIS network).
- Awareness outreach using SMS, sirens, radio, and door-to-door alerts.
- Infrastructure resilience via tsunami-resilient constructions, elevated safe zones.
Coordinated crisis management across national, state, and local bodies.
Best Practices
- Tsunami Vulnerability Zones: Countries like Japan, Chile, and the U.S. West Coast conduct regular drills, enforce tsunami evacuation routes, and maintain community shelters.
- Real-time seismic monitoring (like INCOIS) integrates global data networks and automated alerts to ensure readiness.
- Community drills, education, and resilient urban planning are essential for preparedness and resilience.
Way Forward
Focus Area | Action Items |
Monitoring & Alerts | Enhance seismic and ocean sensors; ensure real-time data sharing |
Public Awareness | Regular community drills; address warning fatigue via meaningful alerts |
Infrastructure Resilience | Implement coastal zoning, build elevated shelters, train first responders |
Policy & Coordination | Strengthen coordination across agencies; invest in R&D for prediction methods |
Global Collaboration | Share best practices; align with UNESCO-IOC Pacific Tsunami Warning System |
Conclusion
Alaska’s recent quakes serve as a stark reminder that shallow-focus seismic activity in subduction zones demands enduring vigilance—from monitoring and emergency response to community engagement and infrastructure resilience. India, informed by frameworks like the NDMA guidelines, must continue investing in early warning systems, coastal planning, and public preparedness, learning from global best practices to safeguard its own vulnerable zones.
Prelims MCQ
Q. With reference to earthquakes, consider the following statements:
- Primary (P) waves are the fastest seismic waves and can travel through both solids and liquids.
- Richter scale and Moment Magnitude Scale (Mw) are both used to measure the energy released by an earthquake.
- Seismographs record ground motion and help determine the epicenter and depth of an earthquake.
Which of the statements given above is/are correct?
A. 1 and 2 only
B. 2 and 3 only
C. 1 and 3 only
D. 1, 2 and 3
Answer: D. 1, 2 and 3
Explanation:
- Statement 1 – Correct. P-waves are longitudinal waves and are the fastest. They travel through solids, liquids, and gases, unlike S-waves which cannot travel through liquids.
- Statement 2 – Correct. The Richter Scale is an older method, while the Moment Magnitude Scale (Mw) is currently preferred. Both measure magnitude, i.e., the energy released.
- Statement 3 – Correct. Seismographs (or seismometers) detect and record seismic waves, helping determine location (epicenter), depth, and magnitude.
Mains Question
Q. In the context of the recent earthquakes in Alaska, examine the geological reasons for such seismic activity and suggest measures for tsunami preparedness in coastal regions. (10 marks, 150 words)
