In News:

China approved the construction of the world's largest dam, stated to be the planet's biggest infra project, on the Brahmaputra river in Tibet close to the Indian border, raising concerns in India and Bangladesh.

Key highlights:

Overview of the Project:

• Location: Lower reaches of the Yarlung Zangbo River (Tibetan name for Brahmaputra), where the river makes a U-turn in the Himalayan region before flowing into Arunachal Pradesh, India.
• Purpose:
  • To support China’s carbon neutrality goals.
  • To boost industrial growth and create jobs in Tibet.
  • Expected to generate 300 billion kWh of electricity annually, over three times the capacity of the Three Gorges Dam in central China.

Significance:

• Scale: The dam is poised to be the world’s largest hydropower project, surpassing the Three Gorges Dam, and becoming the biggest infrastructure project globally, with an estimated cost of USD 137 billion.
• Engineering Challenges: The site is located in a seismic zone on the Tibetan plateau, prone to earthquakes, making construction and operational stability a major engineering challenge.

Concerns:

• Environmental Impact:
  • Potential disruption to the local ecosystem and biodiversity.
  • Risk of altering the river’s flow and course, which could impact agriculture and water resources downstream, particularly in India and Bangladesh.
• Geopolitical Risks:
  • Water control: India and Bangladesh are concerned about China’s ability to control the water flow, with fears of China manipulating the flow to release excess water during conflicts, causing potential flooding in border areas.
  • The project could also disrupt the hydrological cycle, affecting the region’s water availability, especially in Assam and Bangladesh.

Background:

• The Brahmaputra River is a trans-boundary river, flowing through China, India, and Bangladesh. Known by different names in these countries, it plays a vital role in the livelihoods of millions of people.
• China has already initiated hydropower generation on the upper reaches of the Yarlung Zangbo, with plans for additional projects upstream.

India-China Cooperation:

• China and India have an Expert Level Mechanism (ELM) in place since 2006 to manage trans-boundary river issues, under which China shares hydrological data with India, especially during the flood season.
• India is also constructing its own hydropower projects on the Brahmaputra in Arunachal Pradesh.

Potential Outcomes:

• Energy Generation: The dam could significantly contribute to China’s energy needs, providing a substantial amount of renewable energy.
• Regional Tensions: The dam’s construction may escalate tensions between China, India, and Bangladesh due to the control over water resources and environmental impact concerns.

In News:

NASA scientists announced that the Parker Solar Probe survived the closest-ever approach to the Sun. The craft was operating normally after it passed just 6.1 million km from the solar surface.

About the Parker Solar Probe:

• Launched: August 12, 2018, as part of NASA’s Living With a Star program.
• Named After: Eugene Newman Parker, a solar astrophysicist, marking the first NASA mission named after a living researcher.
• Mission Objectives:
  • To study the Sun’s corona and the solar wind, investigating why the corona is hotter than the Sun’s surface.
  • To explore the origins of solar winds and high-energy particles that impact space weather.
  • To understand the structure and dynamics of plasma and magnetic fields around the Sun.
  • To examine the mechanisms behind the acceleration and transportation of energetic particles.

Technological Feats:

• Heat Shield: Equipped with a 4.5-inch carbon-composite shield that withstands temperatures up to 1,377°C (2,500°F) while keeping the instruments cool at about 29.4°C (85°F).
• Speed: Travels at a speed of 692,000 km/h (430,000 mph), making it the fastest human-made object.
• Venus Flybys: Uses gravitational assists from Venus to gradually reduce its orbit and get closer to the Sun.

Historic Milestone:

• Closest Approach: On December 24, 2024, Parker Solar Probe reached a historic distance of 6.1 million km from the Sun's surface, the closest any human-made object has ever been.
  • Comparison: If the Earth and Sun were 1 meter apart, Parker Solar Probe would be just 4 cm from the Sun.
  • Temperature: At its closest, it endured temperatures up to 1,377°C.

Significance of the Mission:

• Scientific Contributions:
  • Solar Wind: Helps scientists understand the origins of solar winds, which affect space weather and Earth’s technological systems.
  • Corona Heating: Investigates why the Sun's corona is much hotter than its surface (a long-standing astrophysical mystery).
  • Space Weather: Provides critical data for predicting space weather events that can impact satellites, communication systems, and power grids on Earth.
• Practical Implications:
  • Improves understanding of space weather, potentially aiding in the protection of Earth’s infrastructure from solar storms.
• Technological and Engineering Marvel:
  • Demonstrates advanced spacecraft technology that can withstand extreme conditions close to the Sun.

Recent Developments:

• Data Collection: As the probe passed through the Sun’s outer atmosphere (the corona), it collected valuable data expected to answer fundamental questions about solar behavior.
• Communication: Despite the extreme proximity to the Sun, the probe sent back a signal on December 26, confirming its status.

Key Dates:

• Launch: August 12, 2018.
• Closest Approach: December 24, 2024.
• Data Expected: Detailed telemetry data on January 1, 2025.

In News:

Indian Army Contingent Departs for 18th Edition of Exercise SURYA KIRAN (India-Nepal Joint Military Exercise).

Key Highlights:

• Event Overview:

• Name: 18th Edition of Battalion-Level Joint Military Exercise SURYA KIRAN.
• Dates: 31st December 2024 to 13th January 2025.
• Location: Saljhandi, Nepal.
• Participants: Indian Army (334 personnel, led by a Battalion from the 11th Gorkha Rifles) and Nepal Army (Srijung Battalion).

• Objective of Exercise:

• Enhance interoperability in jungle warfare, counter-terrorism operations in mountainous terrain, and Humanitarian Assistance and Disaster Relief (HADR) under the UN Charter.
• Focus on operational preparedness, aviation training, medical aspects, and environmental conservation.

• Key Features:

• Training Focus: Improving combat skills and coordination to operate together in challenging situations.
• Exchange of Ideas: Soldiers from both nations will share best practices, enhance mutual understanding of operational procedures.
• Strengthening Bilateral Relations: Reinforces strong bonds of friendship, cultural linkages, and defense cooperation between India and Nepal.

• Significance:

• Historical Context: Exercise held alternately in India and Nepal since 2011.
• Enhances Combat Readiness: Prepares both armies to address shared security challenges and improve operational capabilities.
• Diplomatic Engagement: Fosters a productive professional environment between India and Nepal.

• Recent Developments:

• The exercise follows visits by General Upendra Dwivedi (Indian Army Chief) to Nepal and General Ashok Raj Sigdel (Nepali Army Chief) to India, strengthening military ties.

• Previous Editions:

• 17th Edition: Conducted in Pithoragarh, Uttarakhand (24th Nov - 7th Dec 2023).

In News:

• Archaeological Survey of India (ASI) discovered rock grooves created during the Neolithic age near Boothapandi village, Kanniyakumari district.
• The discovery was made by K. Hari Gopalakrishnan (Archaeological Officer, Tirunelveli and Kanniyakumari districts) and M. Faisal (Sembavalam Research Centre).

Key Highlights:

• Groove Characteristics:

• The grooves are approximately 4,000 years old, formed by Neolithic people for tool sharpening.
• Tools used for activities like hunting, ploughing, and digging were sharpened here.
• The grooves resulted from wear and tear of tools that had broken or worn out during use.

• Groove Dimensions:

• Largest groove: 15 cm in length, 4 cm in width.
• Smallest groove: 8 cm in length, 3 cm in width.

• Similar Discoveries:

• Similar grooves have been found in other parts of Tamil Nadu, including Krishnagiri, Tiruvannamalai, and Villupuram.

• Significance:

• The grooves provide evidence of Neolithic human habitation in the region.
• Ongoing excavations are expected to uncover more about Neolithic culture in the area.The Hindu 

In News:

La Niña, a phase of the El Niño Southern Oscillation (ENSO), occurs when the Pacific Ocean region between Indonesia and South America is cooler than usual. This phenomenon influences global weather patterns, including those in India. Here’s how La Niña specifically affects India’s climate:

Monsoon Rainfall:

• La Niña typically results in normal to above-normal rainfall during the monsoon season in India. This is due to the cooling of sea surface temperatures in the central Pacific, which affects atmospheric circulation and strengthens the monsoon winds.
• In contrast, El Niño usually brings below-average rainfall and droughts to India, leading to agricultural stress.
• Recent La Niña years (2020-2022) saw above-normal monsoon rains, which benefited agricultural productivity, while the El Niño year of 2023 resulted in below-normal rains, impacting water availability and agriculture.

Winter Temperatures:

• During La Niña, winter temperatures in India are generally colder in the north, with cooler nights but relatively warmer days compared to El Niño winters. The planetary boundary layer height (PBLH) tends to be lower, trapping pollutants close to the surface. However, higher wind speeds during La Niña help to disperse air pollution, improving air quality.
• South India may experience colder-than-usual winters during La Niña, but current meteorological data suggests the ongoing winter in India is not strongly influenced by La Niña, as its expected onset has been delayed.

Impact on Summer Heat:

• La Niña generally provides relief from extreme summer heat, as it reduces the frequency and intensity of heatwaves. In contrast, El Niño summers are typically hotter and bring record-breaking heat waves.
• For example, April 2023 saw intense heatwaves across India, attributed to the El Niño phase, but if a La Niña forms and persists into the summer of 2025, it could help moderate the extreme heat.

The "Triple Dip" La Niña Phenomenon:

• A Triple Dip La Niña refers to a rare occurrence where three consecutive La Niña events happen, as was the case from 2020 to 2022. This is significant because these prolonged events can lead to stronger climatic impacts. In contrast, the current El Niño (2023) follows this period, potentially contributing to an irregular transition between La Niña and El Niño phases, which may intensify extreme weather patterns.

Global Climate Changes and La Niña:

• Climate change is believed to be increasing the frequency and intensity of both La Niña and El Niño events. Rising sea and land temperatures are disrupting the balance of the Pacific Ocean and could exacerbate extreme La Niña events, which might lead to harsher winters in India and other regions.

Forecast for 2024-2025:

• As of December 2024, the India Meteorological Department (IMD) and global meteorological bodies predict a weak La Niña event to emerge by late 2024 or early 2025. This could lead to colder winters and above-normal rainfall in the 2025 monsoon season, offering some relief from the heatwaves and dry conditions of the previous years.

Conclusion:

If a La Niña forms by the end of 2024, it is likely to bring cooler winters, a relief from extreme summer heat, and above-normal monsoon rainfall in 2025. Given the delayed onset and weakening of the current La Niña, the overall impact on India’s climate in the immediate future might be milder compared to previous La Niña years, but it still holds potential for more favorable conditions for agriculture and air quality.