Daily Prelims Newsletter for upsc 18 May 2022

Daily Prelims Newsletter For UPSC
| RaghukulCS

18 May 2022-Wednesday

Table Of Contents

Table of Contents

Heat Islands in Cities

Why is this newsworthy?

Several sections of India have recently experienced significant heat waves. The temperatures in urban areas and cities are higher than in rural areas. “Urban Heat Island” is the name given to this phenomena.

These temperature differences, according to experts, are produced by differences in heating across highly urbanised and semi-urbanized areas, as well as the relative availability of open and green spaces in the surrounding areas.

What is the definition of an urban heat island?

An urban heat island is a localised and transient phenomena in which particular areas of a city have higher heat loads than the surrounding area.

This spike in temperature is primarily caused by concrete buildings and dwellings in cities, where heat is trapped and cannot easily evaporate.

The urban heat island is caused by trapped heat between concrete structures.

Temperature changes of 3 to 5 degrees Celsius are possible.

Why do cities have higher temperatures than rural areas?

  • Greener areas were shown to have lower temperatures than non-green areas.
  • Green vegetation, such as plants, trees, and forests, have an important role in reducing the occurrence of urban heat islands.
  • Plantations, farmlands, woods, and trees provide more green cover in rural areas than in urban ones.
  • Transpiration is a process through which plants regulate their temperature.
  • The primary cause of Metropolitan Heat Island in urban areas is pollution.
  • Urban heat islands have become more common as a result of the frequent building of highrise structures, roads, parking spaces, pavements, and public transportation transit lines.
  • It can be found in black or any other dark-colored material.

What Causes the Heat Island Effect in Cities?

Construction activity has increased dramatically: Carbon-absorbing materials such as asphalt and concrete are required for the evolution of cities, from small urban residences to complex infrastructures. They trap a lot of heat, which raises the average surface temperature of cities.

Dark surfaces: Many buildings in urban areas have dark surfaces, which reduce albedo and increase heat absorption.

Buildings with dark surfaces heat up more quickly and require more air conditioner chilling, which consumes more energy from power plants, resulting in more pollution. Furthermore, air conditioners exchange heat with ambient air, resulting in additional local heating. As a result, the spread of urban heat islands is aided by a cascading effect.

  • Tall buildings, as well as the often associated small streets, obstruct air circulation, diminish wind speed, and thus reduce any natural cooling effects. The effect is known as the Urban Canyon Effect.
  • A public transit system is required: Warmth is also added to metropolitan areas by transportation infrastructure and the unrestricted use of fossil fuels.
  • A lack of trees and green areas obstructs evapotranspiration, shading, and carbon dioxide removal, all of which serve to chill the surrounding air.

What can be done to reduce urban heat islands?

Plantation and efforts to increase the area under green cover are the most important requirements for reducing heat load in metropolitan settings.

Passive Cooling to Reduce Heat Islands in Cities: Passive cooling, a widely utilised approach for creating naturally ventilated buildings, can be a vital alternative for residential and commercial buildings to alleviate the urban heat island.

In the context of global warming, the IPCC report highlights ancient Indian architectural designs that utilised this technology, which may be adapted to current facilities.

  • Use of proper construction materials is another form of heat reduction.
  • To reflect heat and prevent absorption, roofs and terraces should be painted white or light colours.
  • Kitchen gardening and terrace vegetation should be encouraged.

What has NASA said about urban heat islands in India?

Heat islands are becoming more common in Delhi’s urban areas, according to NASA.

The temperature in the city of Delhi was substantially greater than in the surrounding farmlands.

NASA’s Ecosystem Spaceborne Thermal Radiometer Experiment (Ecostress) captured the image, which shows a large red area over Delhi and smaller red patches near neighbouring cities Sonipat, Panipat, Jind, and Bhiwani.

NASA launched Ecostress, a radiometer-equipped gadget, to the International Space Station in 2018.

Ecostress is in charge of determining the temperature of plants, as well as their water requirements and the impact of the climate on them.

These red regions in the Ecostress data exhibited higher temperatures, indicating urban heat islands, whereas rural areas around cities had lower temperatures.

Cyclones in pairs

Why is this newsworthy?

Twin cyclones named cyclone Asani and cyclone Karim have been captured in recent satellite photographs in the Indian Ocean region, one in the northern hemisphere and the other in the southern hemisphere.

What is the difference between Cyclone Karim and Asani?

  • With winds of 112 kilometres per hour, Hurricane Karim is a category II hurricane (kmph).
  • With wind speeds of 100-110 kmph gusting to 120 kmph, Asani remains a Severe Cyclonic Storm over the Bay of Bengal.
  • Both of these creatures originated in the Indian Ocean.
  • Both cyclones formed at the same latitude and are presently migrating apart.
  • In the open waters west of Australia, Cyclone Karim has carved a course.
  • The Seychelles, a South African country, gave Karim his name. Sri Lanka suggested the name Cyclone Asani.

Twin Cyclones: What Are They?

  • These synchronous cyclones are created by the interaction of the wind and monsoon systems with the Earth system.
  • The equatorial Rossby waves are to blame for the twin tropical cyclones.
  • Rossby waves are massive ocean waves with wavelengths of 4,000–5,000 kilometres.
  • Rossby waves are named after Carl-Gustaf Rossby, a notable meteorologist who was the first to explain that these waves were caused by the Earth’s rotation.
  • A vortex in the northern hemisphere and another in the southern hemisphere exist in this system, and one is a mirror image of the other.
  • The northern hemisphere vortex spins counterclockwise and has a positive spin, whereas the southern hemisphere vortex spins clockwise and has a negative spin.
  • The vorticity, which is a measure of rotation, is positive in both cases.
  • These Rossby waves frequently produce twin cyclones.

What Causes Cyclones to Form?

When the vorticity in both the Northern and Southern hemispheres is positive, as it is with Rossby waves, the moist air in the boundary layer is elevated slightly.

That is sufficient to initiate a feedback loop.

Water vapour condenses when the air is elevated slightly, forming clouds. The latent heat of evaporation is released as it condenses.

The atmosphere warms, the parcel of air rises, and the process triggers positive feedback. Because it is lighter than the surrounding air, the warmer parcel of air can rise higher and form deeper clouds.

If you have westerly winds at the lower level and easterly winds at the upper level, cyclones will not form if the difference between them is too great.

Cyclones will form even if the difference is small.

There will be a large, tall vortex inside with a variety of clouds. They will spin faster and faster as they grow stronger, eventually becoming large storms.

Is it necessary for the two cyclones to move to different hemispheres?

Yes, they will normally go west once formed. They will have a somewhat northerly component of motion in the Northern Hemisphere, whereas they will have a slightly southern component in the Southern Hemisphere.

As a result, the cyclone in the northern hemisphere is travelling north and west, while the one in the southern hemisphere is moving south and west.

Is the Madden-Julian Oscillation (MJO) Associated with Twin Cyclones?

The MJO is a huge cloud and convection cluster that spans 5,000-10,000 kilometres.

It’s made up of a Rossby wave and a Kelvin wave, both of which are types of wave structures seen in the ocean. The Kelvin wave is on the MJO’s eastern side, while the Rossby wave is on the MJO’s western, trailing edge, with two vortices on either side of the equator.

The MJO does not, however, cause all tropical cyclones. It’s occasionally just a Rossby wave with two eddies on each side.

The First 5G Tested in India

Why is this newsworthy?

The country’s first 5G testbed was recently inaugurated, allowing start-ups and industrial companies to test their products locally, minimising reliance on facilities outside.

What Importance Does This Step Have?

  • It was a significant step toward self-reliance in the telecom sector in terms of crucial and advanced technologies.
  • The 5G testbed was built at a cost of approximately Rs. 220 crore.
  • Because there was no 5G testbed in the United States, entrepreneurs and other industry players had to fly abroad to test and certify their products before they could be installed in a 5G network.
  • 5Gi, India’s native 5G standard, has been developed and will play an important role in bringing 5G technology to the country’s villages.
  • IIT Hyderabad and IIT Madras collaborated to produce the 5Gi standard, which is essentially a Made in India 5G standard (Chennai).

What exactly is 5G?

  • 5G stands for fifth-generation mobile network. After 1G, 2G, 3G, and 4G networks, it is a new global wireless standard.
  • It allows for the creation of a new type of network that connects nearly everyone and everything, including machines, objects, and gadgets.
  • Internet speeds in the 5G high-band spectrum have been tested to reach 20 Gbps (gigabits per second), while the greatest internet data speed in 4G has been reported at 1 Gbps in most circumstances.
  • In India, the Satcom Industry Association-India (SIA) has expressed reservations about the government’s decision to include millimetre Wave bands in the 5G spectrum auction.

5G technology would have a positive impact on the country’s governance, as well as the convenience of living and doing business.

Agriculture, health, education, infrastructure, and logistics all stand to benefit from this.

This will also improve convenience while also creating several job chances.

What are the obstacles to India’s 5G deployment?

  • Low Fiberization Footprint: India needs to enhance its fibre connectivity, which currently connects only 30% of the country’s telecom towers.
  • This number needs to double for a successful 5G launch and uptake in India.
  • ‘Made in India’ is a phrase that means “made in India.” The prohibition on certain foreign telecom OEMs (original equipment manufacturers), which are responsible for the majority of 5G technology development, is an obstacle in and of itself.
  • High Spectrum Costs: India’s 5G spectrum costs are several times higher than the worldwide average.
  • India’s cash-strapped carriers would suffer as a result.
Selecting the Most Appropriate 5G Technology Standard:
  • To speed the adoption of 5G technology, the battle between the domestic 5Gi standard and the global 3GPP standard must be resolved.
  • While 5Gi has clear advantages, it also increases the cost of launching 5G India and poses interoperability challenges for telecoms.
  • 3GPP is a project agreement between telecoms industry partners (Organizational Partners) for formalising worldwide mobile 3G wireless networks based on radio access technologies and GSM specifications.
Next Steps
  • If the government is to realise the 5G India promise, it must support and boost indigenous 5G hardware manufacture at an unprecedented rate.
  • The government must rationalise spectrum pricing in order to collect sufficient cash from the auction without jeopardising India’s 5G development ambitions.
  • 5G may be used in a variety of band spectrums, with the low band spectrum having a significantly longer range, which is beneficial in rural locations.

Other’s News

Syndrome of Sudden Infant Death

Researchers have discovered a molecular signature in the blood that could aid in the identification of newborn newborns at risk of Sudden Infant Death Syndrome (SIDS).

SIDS is the sudden death of a seemingly healthy baby under the age of one year, generally while sleeping.

Because newborns frequently die in their cribs, SIDS is also known as crib death.

Butyrylcholinesterase (BChE) is an enzyme that is involved in the arousal pathway in the brain.

  • The researchers discovered that newborns who died of SIDS had decreased levels of the BChE enzyme shortly after delivery in their latest study.
  • As a result, low BChE levels impair a sleeping infant’s capacity to wake up or respond to its surroundings, resulting in SIDS death.
  • Physical (brain abnormalities, low birth weight, respiratory illness) and environmental factors are the other explanations (sleeping on the stomach or side, sleeping on a soft surface, sharing a bed or overheating)
  • Risk factors – Between the second and fourth months of life, infants are most vulnerable.
  • Boys have a somewhat higher death rate than girls. SIDS is more likely to occur in nonwhite infants.
  • SIDS is more likely in babies who live with smokers (Secondhand smoke).
  • SIDS is caused by premature birth and low birth weight newborns.
  • During pregnancy, the mother has an impact on her baby’s risk of SIDS, particularly if she is under the age of 20, smokes, takes drugs or alcohol, and/or receives insufficient prenatal care.
  • Prevention – Based on the foregoing hazards, activities such as putting your infant to sleep on his or her back, etc., should be taken.
  • SIDS is reduced when a baby is breastfed for at least six months.

Lake Anang Tal

  • A Union Minister has asked the Delhi Development Authority (DDA) to repair the historic Anang Tal Lake in Mehrauli, South Delhi.
  • Anang Tal Lake is thought to have been constructed over a thousand years ago.
  • In 1,060 AD, Tomar King Anangpal II is supposed to have created it.
  • Maharaja Anangpal is Prithviraj Chauhan’s maternal grandfather, hence Anang Tal has a strong Rajasthan connection.
  • The millennia-old Anang Tal marks the start of Delhi.
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