The Hindu Editorial Summary

Editorial Topic : Chennai: A Case Study for Urban Heat Management in India

 GS-1 Mains Exam : Geography

Revision Notes

 

Question : Discuss the concept of Urban Heat Islands (UHIs) and their impact on cities like Chennai. How do UHIs exacerbate the effects of heatwaves, and what are the specific challenges faced by coastal cities in this regard?

Facts and Figures:

• 2023: Hottest year on record according to World Meteorological Organization (WMO). Global average temperatures reached 1.45° C higher than pre-industrial levels.
• Urban Heat Island (UHI): Cities experience several degrees higher temperatures than surrounding rural areas due to concrete structures, tarmac roads, lack of green spaces, and waste heat.

Chennai Case Study:

• Coastal city facing additional challenge of high humidity, reducing the cooling effect of perspiration.
• UHI effect adds 2° to 4° C to temperatures in Chennai compared to nearby areas.
• Wet-bulb temperature in Chennai can reach 38.5° C, near the limit of human survivability according to WHO.
• Heatwave is declared in coastal areas when temperatures exceed 37° C and are 4.5° C above normal. Chennai’s UHI effect makes heatwave conditions more likely and dangerous.

Government Initiatives:

• National, State, and district-level Heat Action Plans (HAP) to reduce heatwave risks.
• National Disaster Management Authority (NDMA) Guidelines outline measures like early warnings, adjusted work hours for outdoor workers, and providing drinking water and oral rehydration salts.

Solutions for Urban Heat Mitigation in Chennai

Increasing Green Cover:

• Priority action: Create green spaces like parks, forests, trees along avenues, and lawns.
• Benefits: Release moisture for cooling, improve air quality, promote health and well-being.
• UN Habitat recommends green spaces within 400 meters of every residence for sustainable development.

Combating Heat from Air Conditioners:

• Air conditioners are a major contributor to UHI due to waste heat.
• Chennai (and other metros) use nearly 50% of summer electricity for air conditioning.
• Shifting to energy-efficient (EE) ACs (5-star or split units) with incentives for replacing older models could reduce UHI by 1.5°C (as seen in Shanghai and Seoul).
• Additional measures in East Asian cities:
  • Mandating 25°C thermostat settings in offices and commercial buildings.
  • Switching off ACs completely (not just standby mode) to save energy.
  • Educating residents about climate change and cost savings (25% on electricity bills).
• Green building practices: improve insulation, ventilation, and use appropriate materials to reduce reliance on ACs.

Other Urban Design Solutions:

• Permeable pavements using alternative materials.
• Increased shrubbery along sidewalks and dividers.
• Reflective paint on roofs, walls, and streets.

Reducing Reliance on Personal Vehicles:

• Invest in rapid public transport with electric buses to decrease traffic and heat emissions.

Learning from Chennai’s Climate Action Plan:

• Chennai is a leader in adopting a Climate Action Plan, but more needs to be done.
• The city has an opportunity to implement long-term solutions for cooling the city and improving livability, becoming a role model for other Indian cities.

 

 

The Hindu Editorial Summary

Editorial Topic : Private Rockets- New Era of Space Exploration in India

 GS-3 Mains Exam : Science and Technology

Revision Notes

 

Question : Analyze the benefits and challenges of public-private partnerships in India’s space sector. How can collaboration between ISRO and private startups like Agnikul Cosmos foster technological advancements and knowledge sharing?

Agnibaan – A Private Success Story

• On May 30, Agnikul Cosmos’s “Agnibaan” rocket had its first successful test flight (Suborbital Tech Demonstrator or SOrTeD mission).
• This was Agnikul’s 5th attempt after facing suboptimal launch conditions earlier.
• Agnibaan is a two-stage, 14-tonne launch vehicle designed for carrying small satellites to low-earth orbits.
• Notably, many components (including engines) are 3D-printed, allowing Agnikul to potentially build one rocket per month.
• This test flight is a major step towards Agnibaan becoming a full-fledged launch vehicle.
• It will add to India’s commercial launch services, catering to the growing market for small satellites.
• Currently, ISRO’s PSLV dominates the launch service, soon to be joined by the Small Satellite Launch Vehicle.
• Agnikul needs to improve communication regarding test flight parameters, an area where ISRO has also faced criticism.

Beyond Commercial Gains: The Broader Impact

• Private rocket flights (like Agnibaan and Skyroot’s Vikram in 2022) offer more than just commercial benefits.
• ISRO’s technical expertise and physical systems are being leveraged by these startups, reducing their development time and costs.
• In turn, these startups can potentially accelerate innovation for ISRO through knowledge sharing.
• For instance, ISRO’s semi-cryogenic engine development could benefit from Agnikul’s experience.
• Supportive government frameworks are crucial to ensure a free flow of knowledge between ISRO and private players.
• This knowledge sharing is exemplified by ISRO’s development of carbon-carbon composite engine nozzles for PSLV.
• This advancement, made possible by knowledge transfer within the space sector, increased PSLV’s payload capacity by 15 kg.
• As more players enter the spacefaring arena, these collaborations can lead to breakthroughs across various scientific fields.

Conclusion

• Private rocket ventures mark a new era of possibilities in space exploration for India.
• The implications are far-reaching, impacting science, technology, economics, and society as a whole.

Additional Information (Arora IAS Inputs)

1.About Cryogenic Engine

A cryogenic engine is a type of rocket engine that utilizes extremely low-temperature liquefied gases as its fuel and oxidizer, known as cryogenic propellants.

Here’s a breakdown of key aspects of cryogenic engines:

• Functioning Principle: Cryogenic engines operate on the principle of combustion, but instead of using gases at normal temperatures, they leverage ultra-cold liquefied gases. This allows for much more efficient burning of fuel and oxidizer, resulting in greater thrust for the engine.
• Fuel and Oxidizer: Common cryogenic fuels include hydrogen and Liquefied Natural Gas (LNG). Liquid oxygen serves as the typical oxidizer.
• Challenges: Maintaining cryogenic fuel and oxidizer at such low temperatures presents a significant hurdle. Additionally, these engines necessitate specialized materials capable of withstanding these extreme cold conditions.

Advantages of Cryogenic Engines:

• Higher Thrust: Compared to conventional rocket engines, cryogenic engines deliver considerably more thrust. This translates to propelling spacecraft farther with less fuel.
• Environmentally Friendly: Cryogenic fuels produce minimal pollution upon combustion, making them more eco-friendly compared to traditional rocket fuels.

Cryogenic Engines in Space Programs:

Cryogenic engines hold immense significance for various space programs, especially for vehicles carrying heavy payloads and deep space missions. Many countries, including India, are actively developing their own indigenous cryogenic engines.

2.About PSLV

PSLV stands for Polar Satellite Launch Vehicle. It’s an expendable, medium-lift launch vehicle designed and operated by the Indian Space Research Organisation (ISRO). Here are some key points about PSLV:

• Function: Launches artificial satellites into Sun-synchronous orbits and Low Earth Orbits.
• Capacity: Can carry up to 1,750 kg of payload to Sun-synchronous polar orbits.
• Role: PSLV is known as the “workhorse” of ISRO due to its consistent performance in delivering satellites for various purposes. It has played a crucial role in India’s space missions, including Chandrayaan-1 (lunar mission) and Mars Orbiter Mission (Mangalyaan).
• Advantages: Compared to heavier launch vehicles, PSLV offers a more cost-effective option for deploying satellites in specific orbits.

ISRO is also developing the Small Satellite Launch Vehicle (SSLV) to cater to the growing demand for launching smaller satellites.