Subject: Basic Sciences

Why in the News?

Researchers used the COCO (Center for Climate System Research Ocean Component) 4.9 ocean model to predict how tritium from Fukushima’s 30-year wastewater release will spread across the Pacific under current and future climates.

Tap to read more about the Fukushima Disaster.

About COCO 4.9 Ocean Circulation Model:

• Purpose: Computer-based ocean simulator to study how seawater moves, mixes, and changes over time.
• Method: Divides oceans into layers and grids; calculates current flows and mixing patterns.
• Resolution: Can run in low detail (large grid blocks) or high detail (small swirling eddies).
• Climate Link: Can model impacts of warming oceans, altered currents, and changing circulation.
• Fukushima Application: Created a “virtual Pacific Ocean” to track tritium spread over decades.

Utility in Nuclear Waste Disposal:

• Predicts where, how fast, and how much nuclear contaminants will disperse.
• Maps dispersion pathways for radioactive materials like tritium.
• Estimates arrival times to different ocean regions.
• Models long-term concentrations under various climate scenarios.

Why in the News?

Since 2013, over 5 billion starfish have died along North America’s Pacific coast due to a wasting disease now linked to Vibrio pectenicida, a cholera-related bacterium.

About Starfish (Sea Stars):

• Taxonomy: Belong to phylum Echinodermata; exclusively marine organisms.
• Species: Brisingida, Forcipulatida, Velatida, Valvatida, Spinuloside
• Body Structure:
  • Radial symmetry (adults), bilateral symmetry (larvae)
  • Calcareous exoskeleton for protection
  • Water vascular system for respiration and circulation
• Unique Features:
  • Regeneration: Can regrow lost limbs
  • No blood or brain: Seawater circulates nutrients
  • Eyespots: At arm tips, help sense light
  • Tough skin: Made of calcium carbonate
• Feeding: Carnivorous, detritivorous, and scavengers

Reasons for Mass Deaths (2013–2025):

• Causal Agent: Identified in 2025 as Vibrio pectenicida, a bacterium related to cholera-causing strains.
• Symptoms: Limb detachment; Tissue disintegration; Melting into a pile of gunk.
• Most Affected Species: Sunflower sea stars, which saw a 90% population decline.
• Geographical Spread: Along the Pacific coast from Alaska to Mexico.
• Ecological Consequences:
  • Starfish are keystone predators, especially of sea urchins.
  • Their decline led to urchin population explosions, which overgrazed kelp forests.
  • Resulted in biodiversity loss and reduced carbon sequestration.

Why in the News?

The Winter Fog Experiment (WiFEX) at Delhi’s IGI Airport, has marked 10 years of pioneering research on dense winter fog in North India.

About Winter Fog Experiment (WiFEX):

• Purpose: It is a long-term, open-field research project dedicated to studying winter fog—a major hazard in North India.
• Launch: Initiated in 2015 at Indira Gandhi International Airport, New Delhi.
• Lead Institution: Managed by the Indian Institute of Tropical Meteorology (IITM) under the Ministry of Earth Sciences.
• Supporting Agencies: Supported by the India Meteorological Department (IMD) and the National Centre for Medium Range Weather Forecasting.
• Objective: To understand fog variability, dynamics, and microphysics, and to improve fog forecasting across the Indo-Gangetic Plain.

Key Features:

• Network: Began at Indira Gandhi International Airport; expanded to Jewar Airport (Noida) and Hisar (Haryana).
• Instruments Used: Includes micrometeorology towers, ceilometers, and high-frequency sensors.
• Data Collected: Covers temperature profiles, humidity, wind, turbulence, soil heat flux, and aerosol concentrations.
• Scientific Goal: To model the full fog life cycle and develop operational forecasting systems.
• Next Phase – WiFEX-II:
  • Will provide localized, runway-specific fog forecasts.
  • Will expand to more airports for real-time winter decision-making.

Outcomes:

• Forecasting Model: A high-resolution fog prediction model with 3-km resolution and 85% accuracy for very dense fog (visibility <200 metres).
• Operational Benefits: Reduced flight delays and diversions; enhanced runway safety.
• Research Insights: Clarified the role of air pollution, urban heat islands, and land-use changes in fog formation.
• Significance:
  • Aviation Planning: Helps airlines, pilots, and passengers manage winter fog disruptions.
  • Science-Policy Link: Demonstrates successful collaboration between scientific institutions and public policy to address climate and aviation challenges.

Why in the News?

A new Nature Physics study suggests that warm volcanic rock surfaces may have concentrated organic molecules in watery cracks, triggering life-like chemistry—offering a clue to how protocells formed without membranes before life began.

What are Protocells?

• Overview: Protocells are primitive, cell-like bubbles believed to be early precursors of real biological cells. They were not fully alive but provided a space for early chemical interactions.
• Lack of Complexity: These structures lacked complex parts like organelles or DNA systems but could hold important molecules like RNA and amino acids together.
• Membrane Role: Protocells often formed simple membranes or boundaries, which allowed molecules to stay enclosed and interact more easily—helping early reactions like protein synthesis happen.
• Importance: Although not living, they offered a model of how basic chemistry could evolve into biology, bridging the gap between non-living and living systems.

History of Formation of Protocells:

• Early Earth Conditions: Over 3.5 billion years ago, Earth’s surface had warm water pools and volcanic cracks filled with organic molecules made by natural processes like lightning.
• Compartmentalization: The first step toward life was concentrating useful molecules in one place, so they could start reacting—this led to the idea of bubble-like protocells.
• Old Theories: In the 1920s, Oparin and Haldane proposed that life began in a “primordial soup” with spontaneous chemical reactions in early Earth’s oceans.
• Modern Insights: Newer research suggests cracks in volcanic rock or hydrothermal vents created temperature gradients and water flows that helped form protocells—no complex membranes were needed.

Key Findings in the 2025 Study:

• Lab Setup: Scientists created a 170-micrometre chamber with a warm top (40°C) and cool bottom (27°C), simulating early Earth rock cracks.
• DNA Test: They added DNA and a protein-making kit (PURExpress). Only in the warm-cool chamber did the DNA make green fluorescent protein (GFP), showing real protein synthesis.
• Molecule Gathering: Essential items like DNA, magnesium, and phosphate ions gathered more at the bottom—up to 70 times more concentrated than at the top.
• Cell-Like Behavior: Even without a membrane, the system kept useful molecules inside while letting waste escape, mimicking real cell selectivity.
• Big Implication: This experiment supports the idea that life could start in simple natural environments using just heat, flow, and basic chemicals—long before full cells appeared.

Why in the News?

Authorities have recovered the black box from the crash site of the recent incident in Ahmedabad.

About Black Boxes:

• Purpose: Black boxes are essential flight data recording devices used in aircraft to aid in accident investigation and flight safety analysis.
• Development: Australian scientist David Warren in 1954, developed the first practical FDR after investigating mid-air explosions.
• Color and Visibility: Despite the name, black boxes are painted bright orange with reflective material to make them easily visible after a crash.
• Two Main Types: Aircraft typically have two black boxes:

1. 1. Cockpit Voice Recorder (CVR) and
   2. Digital Flight Data Recorder (DFDR).

• Single Unit: Some aircraft integrate both functions into a single combined unit.
• How does it work?
  • Cockpit Voice Recorder (CVR): The CVR records cockpit audio, including pilot conversations, radio transmissions, alarm sounds, and background noises like engine hum or warning tones.
  • Digital Flight Data Recorder (DFDR): The DFDR logs key flight performance data, including altitude, airspeed, direction, engine parameters, and system operations, capturing thousands of data points per second.
  • Installation Location: Black boxes are usually installed in the tail section of the aircraft, as this area is statistically more likely to remain intact in a crash.
  • Recording Capacity: The CVR records the last 2 hours of cockpit audio on a continuous loop, while the DFDR stores up to 25 hours of flight data.
  • Durability and Protection: Black boxes use solid-state memory chips housed in crash-survivable casings that can endure high-impact forces, extreme temperatures (up to 1,100°C), and deep-sea pressure.
  • Underwater Locator Beacons (ULBs): Each black box includes a beacon that emits signals for up to 30 days, aiding search teams in locating the devices in the event of a water crash.

Use of Black Boxes in India:

• Regulation in India: In India, aircraft crash investigations are conducted by the Aircraft Accident Investigation Bureau (AAIB) under the Ministry of Civil Aviation, using black box data as primary evidence.
• Recent Development (April 2025): India established its first dedicated Flight Recorders Laboratory in New Delhi, strengthening the country’s capability to analyze crash data independently and efficiently.

Why in the News?

The Union Ministry of Power is considering a policy to restrict the temperature range of new air conditioners (ACs) in India to between 20°C and 28°C.

How do Air Conditioners Work?

• Basic Idea: Air conditioners (ACs) work like a heat-moving machine. They take heat from inside your room and push it outside, making the room cooler. They do this using a special fluid called a refrigerant, and a system called the vapour-compression cycle.
• Main Parts and What They Do:
  • Evaporator: This part is inside your room. The refrigerant, which is very cold here, absorbs heat from the indoor air and turns into a gas. It also removes moisture, so your room feels less humid.
  • Compressor: This is outside the house. It squeezes the refrigerant gas, making it very hot (about 90°C) and high-pressure. This part uses the most electricity in the AC.
  • Condenser: The hot gas then flows through the condenser coil outside. It releases heat into the outdoor air and turns back into a liquid.
  • Expansion Valve: This part lowers the pressure of the liquid refrigerant, making it cold again before it goes back to the evaporator to repeat the cycle.
• Refrigerant: The refrigerant is a specially designed gas that changes state easily at low temperatures and pressures, making it ideal for absorbing and releasing heat rapidly. Modern refrigerants like R-32 or R-410A are more energy-efficient and environmentally safer than older ones like CFCs and HCFCs.

Why limit AC Temperature settings?

• Energy Efficiency Data: According to the Bureau of Energy Efficiency (BEE), setting an AC to 24°C instead of a lower setting can save 6% electricity per 1°C increase.
• National Impact: If adopted widely, this temperature setting could help India save 20 billion units of electricity annually.
• Health Risks at Low Temperatures: Temperatures below 18°C are linked to hypertension, asthma, and respiratory infections, especially among children, the elderly, and people with weakened thermoregulation.
• Evidence from Global Studies: Research in Japan, the UK, and New Zealand shows that slightly warmer indoor settings lead to better respiratory and cardiovascular health.
• WHO Recommendation: The World Health Organization advises 18°C as the minimum safe indoor temperature in temperate climates.
• Thermal Comfort Standards: Guidelines like ASHRAE-55 and ISO 7730 suggest optimal indoor temperatures between 20°C and 24°C for lightly clothed people, with adjustments based on local climate and culture.

Global Cooling Trends and the Need for Regulation:

• Global AC Usage Growth: As of 2022, there were an estimated 2 billion air conditioners in use worldwide, with residential units tripling since 2000, especially in India and China.
• Access Gap in Asia-Pacific: Despite this growth, 43% of the Asia-Pacific population still lacks access to adequate cooling solutions.
• Environmental Impact: Air conditioning significantly increases electricity use and carbon emissions, especially in countries with fossil fuel-dependent grids.
• India’s AC Load Projection: By 2030, India’s total connected AC load is expected to reach 200 gigawatts, requiring urgent demand management strategies.
• Consumer Awareness Tools: Initiatives like default settings at 24°C and energy labelling empower consumers to make informed energy-efficient choices.
• Benefits of Regulation: A regulated temperature range can help lower energy consumption, reduce peak power demand, and support public health.