Why in news?: Black carbon (BC) from fossil fuel and biomass combustion darkens the snow and makes it melt sooner. The BC footprint of research activities and tourism in Antarctica has likely increased as human presence in the continent has surged in recent decades.

About :

Introduction:

In an era where environmental consciousness is of paramount importance, the black carbon footprint emerges as a complex and multi-dimensional challenge. Black carbon, commonly referred to as soot, is a fine particulate matter produced from incomplete combustion of fossil fuels, biomass, and other organic materials. It is a significant contributor to global warming, air pollution, and adverse health effects.

Natural causes of Black Carbon :

• Wildfires: Wildfires inject large amounts of black carbon (BC) particles into the atmosphere, which can reach the lowermost stratosphere (LMS) and cause strong radiative forcing. Black Carbon Emissions from the Siberian Fires in 2019 impacting the entire Arctic region.
• Volcanic Eruptions: Black carbon emissions due to volcanic eruption of Mount St. Helens in the United States in 1980 dispersed over long distances by wind patterns.
• Biomass Burning: Natural events like lightning strikes can ignite biomass, such as forests or grasslands, leading to the release of black carbon and other smoke particles. Eg Amazon rain forest fires in South America.
• Vegetation Decay: Black carbon emissions due to vegetation decay is found in peatlands. A notable example is the draining and degradation of peatlands in Southeast Asia, particularly in Indonesia
•  Dust Storms: Wind-blown dust particles can mix with soot and become black carbon aerosols. One notable example is the "Asian Dust" phenomenon, also known as the "Yellow Dust" or "Yellow Sand," which occurs in East Asia.

Anthropogenic causes of Black Carbon:

• Fossil Fuel Combustion: According to the USA,  fossil fuel combustion accounted for approximately 25% of the black carbon emissions in the country.
• Transportation: In 2016, the Indian Institute of Technology (IIT) Delhi conducted a study and found that transportation was a major source of black carbon emissions in Delhi.
• Waste Incineration: Burning of waste in open dumps or poorly controlled incineration facilities can emit black carbon and other pollutants.
• Residential Energy Use: In the Himalayan state of Uttarakhand and Himachal, many households rely on traditional cooking stoves that burn solid fuels like wood, agricultural residues, and dung for their daily cooking needs, significantly contributing in black carbon emissions.
• Deforestation and Land Use Changes: Researchers from the Woods Hole Research Center and the University of California, Irvine, found that deforestation and associated land use changes were responsible for significant black carbon emissions in the Amazon basin.

Significant Impacts of Black Carbon:

• Human Health : Black carbon is a major component of fine particulate matter (PM2.5). Inhalation of PM2.5 can lead to respiratory and cardiovascular problems, particularly in vulnerable populations such as children and the elderly.
• Climate Change: Black absorbs sunlight and contributes to regional and global warming, influencing the Earth's energy balance and climate patterns.  As black carbon settles on the Himalayan glaciers, it accelerates their melting rates.
• Agriculture and Food Security: Black carbon in the atmosphere can reduce sunlight reaching crops, leading to lower photosynthesis rates and potentially reducing crop yields. Crops like rice, wheat, and maize can be particularly affected, impacting food production and availability. Black carbon can alter regional weather patterns, including the timing and intensity of monsoon rains.
• Ecosystems and Biodiversity: Black carbon deposition in Arctic soils affects the temperature and moisture regimes of the soil. This, in turn, can alter the microbial communities living in the soil, which play critical roles in nutrient cycling.
• Tourism and Industry : Poor air quality resulting from black carbon emissions can deter tourists from visiting certain areas, impacting local tourism-based economies. Study finds an increased concentration of black carbon in Gangotri region during tourist seasons.

How Black Carbon Disturbs the Heat Budget of the Earth ?

• Absorption of Solar radiation:   Black carbon particles when released into the atmosphere,  intercept solar radiation and convert it into heat. This process reduces the albedo , warms the surrounding air and contributes to the overall heating of the atmosphere.
• Disruption of Atmospheric Stability: Black carbon in the atmosphere can alter the vertical temperature profile, reducing the stability of the atmosphere. This can impact cloud formation and weather systems, leading to changes in precipitation patterns and atmospheric circulation.
• Affecting Clouds: Black carbon particles can act as cloud condensation nuclei, influencing the formation and properties of clouds. This can lead to changes in cloud behavior, potentially affecting cloud cover and cloud lifetimes, and ultimately impacting the Earth's energy balance.
• Affecting Ocean Circulation : Melting of ice due to black carbon deposition can lead to changes in ocean circulation patterns. As fresh meltwater enters the ocean, it can disrupt the balance of salinity and density, affecting ocean currents and heat distribution.
• Ocean Warming: Black carbon contributes to the heating of the atmosphere when it absorbs sunlight. As the atmosphere warms, it can transfer some of this heat to the ocean through increased evaporation and ocean-atmosphere heat exchange.

Activities undertaken by selected GEF( Global Environment Facility ) Implementing Agencies and other international organizations towards mitigating Black Carbon.

SOLUTIONS TO MITIGATE THE EMISSIONS OF BLACK CARBON

• Cleaner Energy Sources: Transitioning from fossil fuels to cleaner energy sources, such as renewable energy (solar, wind, hydroelectric) and natural gas, can significantly reduce black carbon emissions from power generation, industrial processes, and residential heating. India's initiative to switch from BS IV to BS VI engine vehicles is commendable .
• Improved Cooking Technologies: Promoting the use of improved cookstoves and clean fuels (e.g., LPG, biogas) for cooking can help reduce black carbon emissions from traditional biomass burning in households. The Government of India introduced  PMUY  ( Pradhan Mantri Ujjawala Yojana ) offers BPL households a cash contribution of Rs 1600 for each LPG connection.
• Advanced Emission Control Technologies: Installing and maintaining advanced emission control devices, such as particulate filters and scrubbers, can help capture black carbon and other pollutants from exhaust gases. WAYU (Wind Augmentation PurifYing Unit) was  developed to address air pollution at traffic intersections and dense traffic zones.
• International Cooperation: Addressing black carbon emissions requires collaboration between countries, especially for transboundary pollution. International agreements and partnerships can support collective efforts to mitigate black carbon emissions.

 Conclusion

• The measures to prevent black carbon emissions can reduce near-term warming of the climate, increase crop yields and prevent premature deaths.
• Black carbon’s short atmospheric lifetime, combined with its strong warming potential, means that targeted strategies to reduce emissions can provide climate and health benefits within a relatively short period of time.

Where to use?

Paper 1 ( Geography Optional ) : Global Climatic change, Role and response of man in climatic changes

Source : 

https://www.nature.com/articles/s41467-022-28560-w

https://ui.adsabs.harvard.edu/abs/2022NatCo..13..984C/abstract

Why in news ? : Hotspots beneath cities deform the ground, causing important infrastructure to crack under stress.

About:

• Urban areas absorb heat during the day, making some urban areas up to six degrees Fahrenheit hotter than rural ones. The“urban heat islands”  are  developing underground as the city heat diffuses downward, beneath the surface.
• According to a new study of downtown Chicago, underground hotspots may threaten the very same structures that emit the heat in the first place. Such temperature changes make the ground around them expand and contract enough to cause potential damage.
• Subsurface temperatures rise because of climate change and underground urban development, causing the potential implications for underground ecosystems. For example, if groundwater gets too warm, it could kill or drive away animals, trigger chemical changes in the water and become a breeding ground for microbes.
• Underground hotspots could affect urban infrastructure because materials expand and contract with temperature change. It is suspected that heat seeping from basements and tunnels could be contributing to wear and tear on various structures.
• Chicago’s overall ground temperatures is rising by 0.25 degree F each year. Many cities near oceans and rivers—London, for example, are built on a layer of clay. In contrast, cities built largely on harder rocks (such as New York City), would not be as impacted by this effect.
• Similar to climate change above the surface, these underground changes occur over long periods of time to develop.
• According to researchers , this energy could also be harnessed: Subway tunnels and basements could be retrofitted with geothermal technologies to recapture the heat. For example, water pipes could be installed to run through underground hotspots and pick up some of the thermal energy. However, it requires a high upfront cost.

Where to  use?

Paper 1 (Geography Optional): Physical Condition of earth interior , Urban Heat Island effect

Source:

https://www.scientificamerican.com/article/underground-climate-change-is-weakening-buildings-in-slow-motion1/#:~:text=Underground%20Climate%20Change%20Is%20Weakening%20Buildings%20in%20Slow%20Motion,-Hotspots%20beneath%20cities&text=The%20streets%2C%20sidewalks%20and%20roofs,degrees%20F%20hotter%20at%20night.

https://news.northwestern.edu/stories/2023/07/the-ground-is-deforming-and-buildings-arent-ready/

Why in news ? The Atlantic Meridional Overturning Circulation has been weakening – and new predictions suggest it could totally switch off between 2025 and 2095.

About:

• A major system of ocean currents that ferries heat from the tropics to the North Atlantic could shut down far sooner than expected, according to new predictions.
• The system, known as the Atlantic Meridional Overturning Circulation (AMOC) had previously been measured to be dramatically weakening in conjunction with rising ocean temperatures.
• Shutting down the AMOC can disturb the heat and precipitation at Global level.
• This detailed analysis by researchers suggested significant warning signs of the AMOC shutting down between 2025 and 2095, with a staggering certainty of 95%. More specifically, the most likely time for this collapse would be around 2057.
• The AMOC, which includes the Gulf Stream as part of its system, is our planet's main mode of transporting heat away from the tropics. Without it, the tropics would rapidly increase in temperature while vital tropical rains get disrupted. Such rains are essential for the environments of South America, western Africa as well as in India and other regions of south Asia.
• Meanwhile, northern and western Europe would lose their source of warm water from the tropics, leading to more storms and severely cold winters in these areas. The loss of the Gulf Stream in particular would also result in rising sea levels on the US’ eastern seaboard.
• In recent years, earth has already seen the dangers of human-induced climate warming in form of heatwaves, especially in northern hemisphere. And although the loss of the AMOC may see northern and western Europe cool, “this shutdown will contribute to an increased warming of the tropics.

Where to use?

Paper I (Geography optional): Ocean Currents , Global climatic change

Source :

https://www.usatoday.com/story/news/weather/2023/07/25/atlantic-current-collapse-possible-in-two-years-study-suggests/70434388007/

Piedmont plateaus : The plateaus that are situated at the foot of the mountains and are bounded on other sides by a plain or an ocean are called the piedmont plateau. Eg Malwa plateau in India.

Meta Population management : It consists of a group of spatially separated populations of the same species which interact at some level. Although individual populations have finite life-spans, the metapopulation as a whole is often stable because immigrants from one population are likely to re-colonize habitat which has been left open by the extinction of another population.

Hemipteran :  It is  an order of insects, commonly called true bugs having biting or sucking mouthparts and two pairs of wings. Hemipterans include the leafhoppers, treehoppers, cicadas, aphids, scales, and true bugs.

Snowball earth glaciation : The glaciation were a series of ice ages during the Neoproterozoic era of geologic time, mainly confined to the Cryogenian period, but perhaps also into the Ediacaran period, too. Snowball Earths arose as incoming sunlight is reduced, ice expands from the poles to the equator.

Amphidromic point : Amphidromic points are places where the tidal range (difference in height between high and low tide) is zero compared with other areas in the basin.

• Karla was a natural lake until 1962, when it was drained, and was considered an important ecosystem in the Mediterranean region as it served as a “hot spot” of biodiversity
• Using Nature-Based Solution (NBS) , the ‘Karla’ reservoir in Central Greece, is now restored with the purpose to maximize the efficiency of water provision in agriculture and biodiversity enhancement.
• The reconstructed Lake Karla now can serve as a multi-purpose project to combat water scarcity, achieving a twofold crop yield production and respective agricultural income in the surrounding area, securing the coverage of the water supply needs of the closest city, improving the status of groundwater resources, developing a natural shelter for biodiversity and emerging recreation and touristic opportunities.
• At the same time, its construction and operation costs has been recovered, and the governance plan ensuring the viability of the whole project inspiring similar multi-purpose water retention projects for investment in agriculture and the environment not only in southern Europe but also in other water scarce regions.

Where to use?

Paper I (Geography optional): Sustainable development

Source :

https://www.researchgate.net/publication/343778453_A_Large-Scale_Nature-Based_Solution_in_Agriculture_for_Sustainable_Water_Management_The_Lake_Karla_Case

1. Srivilliputhur Megamalai Tiger Reserve (SMTR): It is the fifth Tiger Reserve of Tamil Nadu, and 51^thtiger reserve of India. It has a mix of tropical evergreen forests and semi-evergreen forests, dry deciduous forests and moist mixed deciduous forests, grassland. It functions as a connecting link between Kerala’s Periyar Tiger Reserve and Tamil Nadu’s Southern Kalakkad-Mundanthurai Tiger Reserve. Recently 12 illegal, unauthorised or unrecognised resorts were identified by state forest department of Tamilnadu around SMTR. (Approx. Virudunagar)
2. Bura Chapori Wildlife Sanctuary: It is a protected area located on south bank of the Brahmaputra River in Sonitpur district of Assam. It forms an integral part of the Laokhowa-Burachapori eco-system and is a notified buffer of the Kaziranga Tiger reserve. Recently one dead and several injured over clash between forest team, illegal encroachers at Bura Chapori wildlife sanctuary. (Approx. Sonitpur)
3. Chamarajanagara: It is the southernmost district in the state of Karnataka, India. It was carved out of the original Mysore District in The district borders the state of Tamil Naduand Kerala. The main tourist attractions are Sri Chamarajeshwara temple and Biligiriranga Hills. Recently , it was in news that it is the only district in India which has three Tiger Reserves-Bandipur Tiger Reserve, Biligiri ranganabetta Tiger Reserve (BRT) and Malai Mahadeshwara Tiger Reserve. (Approx. Mysore)
4. Koli hills: It is a small mountain range located in central Tamil Naduand spread over the Namakkal district and Tiruchirapalli district of India. Recently, it was in news that, Koli hills hydroelectricity plant is to be commissioned soon. (Approx. Namakkal)
5. Charmadi Ghat: It is a  ghat  in Belthangady taluk of Dakshina Kannada and Mudigere taluk of Chikkamagaluru. The Ghat starts from Charmadi village and ends at Kottigehara. . In the Charmadi ghat, there is a waterfall named Bandaje Arb. Recently Cops were deployed on Charmadi Ghat to stop tourists from risking their lives for selfies. (Approx. Belthangady)

Q1. Recently Delhi has witnessed water logging crisis due to rising water levels of Yamuna river. Consider the following pair of dams and states  on the river Yamuna:

         Dam              :            State

1. Lakhwar Vyasi :       Haryana
2. Tajewala. : Uttarakhand
3. Dakpatthar. : Himachal Pradesh

Which of the pairs given above is/ are  correctly matched ?

1. One pair
2. Two pairs
3. Three pairs
4. None

Q2. World Snake Day on 16 July

Consider the following statements regarding Snakes :

1. Snakes are “solar-powered” and rely fully on external heat or light sources.
2. Snakes living in colder regions are not viviparous
3. Snakes do have nostrils, but they don’t use them to smell.

Which of the statements given above are correct ?

1. Only 1
2. Only 1 and 2
3. Only 1 and 3
4. Only 2 and 3

Q3. Recently, NITI Aayog has released the Report ”National Multidimensional Poverty Index: A Progress Review 2023", claiming that a significant number of people have come out of multidimensional poverty in India.

Consider the following :

1. Maternal health
2. Bank accounts
3. Adolescent mortality
4. Flooring

On how many of the above indicators does NITI Aayog focus on for Multidimensional Poverty Index?

1. Only one
2. Only two
3. Only three
4. All four

Q4. New study discovers 62 desiccation-tolerant vascular plant species in India’s Western Ghats, with potential applications in agriculture & conservation. These species of plants can withstand harsh environments.

Which among the following statements is incorrect regarding “Desiccation Tolerant “ ( DT )  species, mentioned recently in news?

1. They can be found in both tropical and temperate regions.
2. In India, these are primarily found in forest rock outcrops and partially shaded tree trunks.
3. These species showed colour variations and morphological characteristics
4. There is a fast germination of seeds in these species.

Q5. Consider the following statements regarding Cicadas:

1. They are certain type of insects responsible for Chagas’ disease.
2. They are mostly herbivorous and feed on plant sap using their piercing and sucking mouthparts.
3. The declining presence of cicadas in homesteads may indicate the deterioration of soil quality and vegetation.

Which of the statements given above are correct ?

1. Only 1 and 2
2. Only 2 and 3
3. Only 1 and 3
4. All of the above

Q6. Which among the following statements is incorrect about Gambusia fishes ?

1. The fish is a native to the southeastern United States.
2. It is widely used as a biological agent to control mosquito larvae.
3. These fishes hijack the food web causing imbalance in the food ecosystem .
4. They are found in deep waters in the mid of water bodies.

Q7. With reference to Hoolock Gibbon , consider the following statements:

1. Western Hoolock Gibbon and Eastern Hoolock Gibbon, both are found in India.
2. Both Western and Eastern Hoolock Gibbon are protected under the Indian (Wildlife) Protection Act of 1972 and included in Schedule 1.

Which of the statements given above are correct ?

1. Only 1
2. Only 2
3. Both 1 and 2
4. Neither 1 nor 2

Q8. Recently, the use of  collars in the cheetah reintroduction project in Kuno Wildlife Sanctuary was in news. With reference to collars, consider the following statements:

1. Electric collars are used to train livestock and other animals to avoid crossing designated boundaries.
2. Cheetahs are vulnerable to local pathogens due to the use of radio collars.

Which of the above mentioned statements is/ are correct ?

1. Only 1
2. Only 2
3. Both 1 and 2
4. Neither 1 nor 2

Q9. Consider the following statements:

1. The most abundant tree species are Sundri and Gewa
2. On the east of it , it is bordered by Baleshwar river.
3. WWF India conducted environment education activities through initiatives such as Nature Clubs of India.

The above statements are related to which among the following:

1. Kaziranga National Park
2. Sunderban mangroves
3. Manas national Park
4. Nokrek National Park

Q10. With reference to ‘ fly ash’ produced by the power plants using coal as fuel, which of the following statements is/are correct?

1. Fly ash can be used in the production of bricks for building construction.
2. Fly ash can be used as a replacement for some of the Portland cement contents of concrete.
3. Fly ash is made up of silicon dioxide and calcium oxide only, and does not contain any toxic elements.

Select the correct answer using the code given below:

1. 1 and 2
2. 2 only
3. 1 and 3
4. 3 only

Q11. Consider the following statements regarding Tiger Orchids :

1. It flowers in alternate years and remains in bloom for about a month.
2. The species is originally from Uttarakhand.
3. It was listed by the Guinness Book of World Records as the world’s tallest orchid.

Which of the above mentioned statements is/ are correct ?

1. 1 and 2
2. 2 and 3
3. 1 and 3
4. All of the above

Q12. Consider the following pairs:

         Parks / Sanctuaries.                 :                    State

1. Srivilliputhur Tiger Reserve : Tamil Nadu
2. Bura Chapori Sanctuary :   Assam
3. Mukurthi National Park. :   Karnataka

Which of the above pairs are correctly matched ?

1. One pair
2. Two pairs
3. Three pairs
4. None of the pairs

Q13. With reference to Little Rann of Kutch, consider the following statements:

1. Little Rann of Kutch is bordered by Rajasthan on one side and Pakistan on the other.
2. The Little Rann of Kutch is home to the a species known as Ghudkhur.

Which of the above mentioned statements is/ are correct ?

1. Only 1
2. Only 2
3. Both 1 and 2
4. Neither 1 nor 2

Q14. Ludwigia peruviana, recently in news is associated with which among the following :

1. It is white chemical used to increase the moisture retention of soil.
2. A beautiful aquatic plant endangered the biodiversity of wetlands in India.
3. It has contributed to the collapse of local fisheries in river Hooghly.
4. It poses a significant threat to elephant habitats, disrupting the growth of essential food sources for elephants 

Q15. With reference to Silver cockscomb , consider the the following statements:

1. It is a troublesome weed with high antibacterial activity and high nutrient content.
2. This weed, prevalent in regions of Southeast Asia and Latin America.

Which of the above mentioned statements is/ are correct?

1. Only 1
2. Only 2
3. Both 1 and 2
4. Neither 1 nor 2