Topic 1 : Prisoner’s dilemma
Why in news: In his speech, Defence Minister of India referred to the concept of “Prisoner’s Dilemma” to underscore the need for countries to collaborate with each other instead of working at cross purposes.
What is Prisoner’s Dilemma?
- The prisoner’s dilemma is a game theory thought experiment that involves two rational agents, each of whom can cooperate for mutual benefit or betray their partner (“defect”) for individual reward.
- Game Theory, which is itself a branch of science, helps understand how people/entities behave under different circumstances.
- By simulating a game, Game Theory also shows how to achieve the best outcome.
- For instance, it may appear straight-forward that a person or a country must always do what appears to provide them with the best pay-off.
- However, the final outcome depends on the actions of other people/countries as well.
- To be sure, the final outcome could change if the other party/parties act in conflict.
- Suppose two people — A and B — are brought in for questioning about a crime.
- However, the evidence with the police is circumstantial and the best that they can hope to achieve is to put both A and B in jail for a year each.
- Unless, of course, they get more credible evidence.
- One way to do this is to get the prisoners to rat out each other.
- So the police officer puts both A and B in separate rooms and provides both of them with a simple choice:
- If one prisoner says the other is involved in the crime, he can go scot-free while the other will be given a 15-year jail term.
- If neither prisoner confesses, they both will only get one year’s jail time.
- Simply put, the prisoner’s dilemma is whether to confess or stay silent.
- What if both confess?
- In that case, their jail times will be 10 years each.
- The pay-offs for each prisoner in this “game” can be summarised in the matrix below:
What should the prisoners do, then?
- The best outcome, of course, lies in co-operation.
- If both prisoners co-operate, they can achieve the best outcome and get away with just a year in prison.
Applications of the dilemma:
- This dilemma (and its answers) has many real life applications both in international law as well as in business.
- For instance:
- should two companies selling the same product keep undercutting each other by reducing the price in order to corner the market share?
- Could repeated use of this strategy lead them to reduce prices to such a level that it becomes economically unviable to stay in business?
- Would it not be better for them to agree on a floor price so that they can both earn healthy enough profits?
- Similarly, should countries set some ground rules in geopolitics to ensure they don’t enter an arms race that will eventually prove ruinous for their own economies and people?Topic 2 : Rapid ice melt in West Antarctica
Why in news: The rapid melting of West Antarctica’s ice sheet due to warm waters around it is now unavoidable, no matter how much carbon emissions are cut, according to a new study.
- If lost completely, the ice sheet would raise the global mean sea level by 5.3 metres or 17.4 feet.
- It is a potentially devastating consequence for millions of people living in vulnerable coastal cities across the world, including in India.
- Even under a best-case scenario of limiting global warming to 1.5 degree Celsius above pre-industrial levels, water in West Antarctica will continue to get warmer three times faster than in the 20th century, leading to an increased melting of the region’s ice sheet.
What is an ice sheet?
- An ice sheet is essentially a mass of glacial ice that covers more than 50,000 square kilometres of land — roughly large enough to blanket Uttarakhand in ice.
- There are two major ice sheets in the world today:
- Greenland ice sheet and
- Antarctica ice sheet.
- Together, they contain about two-thirds of all the freshwater on Earth
- This means that over time, when ice sheets gain mass, they contribute to a fall in global mean sea level, and when they lose mass, they contribute to a rise in global mean sea level.
How is the West Antarctic ice sheet melting?
- There are various processes through which ice sheets melt.
- One of them is when warm ocean waters melt iceshelves.
- Ice shelves are the edges of an ice sheet which floats on the ocean.
- Ice shelves stabilise the land-based glaciers just behind them.
- If an ice shelf thins or disappears, these glaciers tend to speed up, discharging more ice into the ocean and causing sea level rise.
- Both ice shelves and ice sheets are different from sea ice.
- Sea ice is the free-floating ice that surrounds the polar regions.
- Sea ice is created by sea water freezing.
- The same process is taking place in West Antarctica, particularly the Amundsen Sea.
- For decades, the region’s ice shelves have been depleting, glaciers have been flowing faster towards the ocean and the ice sheet has been shrinking.
- Although the findings are bleak, they shouldn’t discourage the efforts to mitigate the impacts of climate change.
- According to the researchers, the melting West Antarctic ice sheet is just one contributor to sea level rise, which is just one impact of climate change.
- We have reached the point where some impacts of climate change can no longer be avoided, and substantial ice loss in West Antarctica is probably one of them.
- There are many other impacts which we can still avoid or limit, like:
- the loss of the East Antarctic Ice Sheet, or
- the severity of heatwaves, droughts, and extreme rainfall.
Topic 3 : Age of Moon
Why in news: The moon is 40 million years older, according to a new study.
- The new study appears to show that the moon is about 40 million years older than previously thought.
- It now seems to have formed about 4.46 billion years (or “GA” — giga annum) ago — putting its formation within the first 110 million years of the birth of our solar system.
- The findings are based on a new technology called atom probe tomography (APT).
How did scientists discover the moon’s new age?
- The scientists reanalyzed crystals from lunar sample 72255, which was known to contain 4.2 billion-year-old zircon — some of the oldest ever found.
- Zircon is also the oldest mineral known to exist on Earth and holds vital information about the formation of our planet and life as we know it.
- The scientists in the new study used APT, which has nanoscale spatial resolution, to determine the clustering of lead in the samples.
- The distribution of lead is commonly used to estimate the age of zircon in rock.
Why is zircon relevant to the age of the moon?
- The leading hypothesis for the formation of the Earth–moon system is the giant impact hypothesis.
- A huge object called Theia, which was possibly the size of Mars, is thought to have collided with Earth as it was forming.
- That caused an ejection of debris that quickly formed into the sphere we call our moon.
- That created what is known as the Lunar Magma Ocean — a theory that explains the composition of the moon’s interior.
- There were subsequent bombardments of the moon’s surface, which reworked and melted the earliest crust, leaving some zircon modified and other zircon pristine, or preserved.
- It was by spotting the preserved zircon within crystal grains from lunar sample 72255 that they were able to redetermine the moon’s age.
How old is the moon compared to the Earth?
- The Earth is estimated to be between 4.5 and 4.6 billion years old.
- That makes the moon only a fraction younger, at 4.46 billion years old.Topic 4 : Cloud seeding
Why in news: IITM Pune demonstrates cloud seeding can produce rainfall
- A cloud seeding experiment carried out in Solapur city was able to achieve 18% relative enhancement in rainfall, which is approximately 8.67mm more rainfall.
- Solapur falls on the leeward side of the Western Ghats and hence gets low rainfall.
- The relative enhancement of accumulated rainfall was seen over two hours after seeding the clouds.
- In all, the total enhancement of water availability through cloud seeding experiments was 867 million litres.
What was the experiment?
- The experiment — Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX phase-4) , was a scientific investigation conducted in Solapur city during the summer monsoon period of 2018 and 2019.
- The primary objective was to investigate the efficacy of hygroscopic seeding in deep convective clouds and to develop a cloud seeding protocol.
How was it carried out?
- The experiment used two aircraft for studying various cloud parameters and for seeding the clouds.
- The study found that cloud seeding is an effective strategy for enhancing rainfall in a region under suitable conditions.
- A randomised seeding experiment was undertaken to study the effectiveness of cloud seeding in producing rainfall.
- In total 276 convective clouds were chosen, and 150 were seeded while the remaining 122 clouds were not seeded.
- The seeded clouds produced more rainfall than the unseeded clouds.
- Calcium chloride flare was used for seeding the clouds.
- A cloud seeding flare releases these particles when triggered.
- The seeding was done at the base of the warm convective clouds and at a time when the clouds were in their growing stage so that the seed particles could enter the clouds with minimum dispersion.
Significant findings of the study:
- Cloud seeding alone cannot mitigate droughts but can help produce 18% more rainfall and partially address water requirements.
- Undertaking cloud seeding as catchment-scale projects can possibly help in managing drought conditions.
- The work provides elaborate protocols and technical guidance to plan and conduct cloud seeding in India.
- The two-year study has helped develop a high-resolution numerical model that can help stakeholders to identify:
- target locations,
- clouds that can be seeded, and
- a suitable seeding strategy to enhance rainfall in an area.
- One of the most important findings of the study was that not all cumulus clouds produce rainfall when cloud seeding is done.
- 20-25% of cumulus clouds produce rainfall if cloud seeding is done correctly.
- Though the relative enhancement of rainfall was 46% as measured by automatic rain gauges, the actual increase in rainfall over a 100 sq.km area was only 18.
- The approximate cost of producing water through cloud seeding was 18 paisa per litre.
- The cost will drop by more than 50% if we use indigenous seeding aircraft.
What is Cloud Seeding?
- Clouds are made up of tiny water droplets or ice crystals that form when water vapor in the atmosphere cools and condenses around a tiny particle of dust or salt floating in the atmosphere.
- Without these particles, known as condensation or ice nuclei, raindrops or snowflakes cannot form and precipitation will not occur.
- Cloud seeding is a weather modification technique that improves a cloud’s ability to produce rain or snow by introducing tiny ice nuclei into certain types of subfreezing clouds.
- These nuclei provide a base for snowflakes to form.
- After cloud seeding takes place, the newly formed snowflakes quickly grow and fall from the clouds back to the surface of the Earth, increasing snowpack and streamflow.
Topic 5 : India bans exports of some rice varieties
Why in news: India banned the export of non-basmati white rice amid depleting public stock in the Central pool, elevated cereal prices, and looming threat of the uneven monsoon.
- Soon after India banned the export of non-basmati white rice, there was a sharp jump in the price of rice across markets.
- In the following months, prices have come down, but are still higher than the pre-ban period.
- Global impact:
- Quotes for trading prices for most grades of regular (neither parboiled nor aromatic) whole-grain milled rice from Thailand decreased 5−6 percent, mostly due to a weaker baht.
- Thailand’s 100-percent Grade B long-grain milled rice for export was quoted at $595 per ton, down $34 but still up more than $60 per ton, prior to India’s implementation of export restrictions.
- Thailand’s price rose rapidly from late July through mid-August, primarily in response to India’s July export ban on regular-milled white rice.
Impact on the domestic prices of rice
- There has been no respite from the increase in the prices of rice despite the export ban.
- The daily average wholesale price of rice was recorded at Rs 5,800 per quintal which was:
- 27.43 per cent higher than a month ago,
- 18.42 per cent higher compared with the price when the government announced the Open Market Sale Scheme (OMSS) in January,
- 5.82 per cent higher as compared to the price recorded when the government put in place export regulations on August 27, 2022, and
- 3.21 per cent higher as compared to the price a year ago.
- Retail and wholesale prices:
- The day India banned the export of non-basmati white rice, the all-India daily average retail price of rice was recorded at Rs 40.89 per kg, which was 11.42 per cent higher than a year ago.
- The all-India average daily wholesale price of rice was recorded at Rs 3,587.34 per quintal, 11.95 per cent higher than a year ago.
How does India export rice? What is banned and what is not?
- India is the biggest exporter of rice in the world.
- India accounted for about 40 per cent of the total rice exports (56 million tonnes) in the world during calendar year 2022.
- India’s rice exports are broadly categorised into:
- basmati and
- non-basmati rice.
- The non-basmati rice category includes 6 sub-categories:
- rice in husk of seed quality;
- other rice in husk;
- husked (brown) rice;
- rice parboiled;
- non-basmati white rice;
- broken rice.
- While the government has banned export of two sub-categories of:
- broken rice and
- non-basmati white rice.
- There is no ban on the remaining four sub-categories.
- In the financial year 2022-23, India’s basmati export stood at 45.61 lakh metric tonnes.
- Top 5 destinations for export:
- Saudi Arabia
- In all, India exported basmati to 149 countries during the last financial year.
- The non-basmati rice includes varieties like Sona Masuri and Jeera rice.
- In financial year 2022-23, India exported 177.91 lakh metric tonnes of non-basmati rice, of which:
- a maximum 78.48 lakh metric tonnes was parboiled rice,
- followed by non-basmati white rice (64.01 lakh metric tonnes), and
- broken rice (30.49 lakh metric tonnes).
- The other three categories accounted for a lower quantity:
- other rice in husk (4.61 lakh metric tonnes);
- rice in husk of seed quality (19.68 thousand metric tonnes); and
- husked (brown) rice (11.65 thousand metric tonnes).
Export of various non-basmati rice varieties:
- Non-basmati White Rice
- Out of the 64.01 lakh metric tonnes of non-basmati white rice.
- Top 3 destinations of export:
- Notwithstanding the ban, non-basmati white rice export is allowed on the basis of permission granted by the Government of India to other countries to meet their food security needs and based on the request of their Government.
- Broken Rice
- In the financial year 2022-23, India’s broken export stood at 30.49 lakh metric tonnes.
- Top 3 destinations of export:
- Par-boiled Rice
- The dictionary meaning of ‘parboil’ is ‘partly cooked by boiling’.
- Thus, the term par-boiled rice refers to the rice that has been partially boiled in paddy form before milling.
- There is no ban on export of this category of rice from India.
- Top 5 destinations of export in the previous year:
- Côte D’ Ivorie, and
- In the current financial year, the top 5 destinations are:
- Somalia and
- Husked (Brown) Rice
- The husked (brown) rice is the type of rice from which only the husk has been removed, while the brown rice is unpolished rice.
- Top 5 export destinations:
- Saudi Arabia, and
- Rice in Husk of Seed Quality
- In the financial year 2022-23, a quantity of 19,681 metric tonnes of rice in husk of seed quality was exported.
- Other Rice in Husk
- India exported a quantity of 4.61 lakh metric tonnes of Other Rice in Husk during 2022-23, of which almost 99 per cent went to Nepal.
- In the current financial year almost the entire quantity has been exported to Nepal.
Rice procurement and requirement
- Total production:
- Total production of rice during 2022-23 is estimated to be at a record 1357.55 lakh tonnes.
- It is higher by 62.84 lakh tonnes than previous year’s Rice production of 1294.71 lakh tonnes and by 153.65 lakh tonnes than the last five years’ average production of 1203.90 lakh tonnes.
- A quantity of 56.04 lakh metric tonnes of paddy has been procured from 8 states:
- Himachal Pradesh,
- Tamil Nadu,
- Uttar Pradesh,
- Uttarakhand, and
- West Bengal.
- A quantity of 56.04 lakh metric tonnes of paddy has been procured from 8 states:
- Under the National Food Security Act, 2013, the monthly requirement (allocation) of rice is about 32 lakh tonnes.
- Taking into consideration other welfare schemes including ICDS, PM-Poshan, the monthly requirement is 35 lakh metric tonnes.
- Rice Stocks in the Central Pool
- As per the Food Corporation of India, a stock of 221.87 lakh metric tonnes of rice is available in the Central Pool as on October 1, 2023.
- In addition to this, a stock of 138.36 lakh metric tonnes of unmilled paddy (equal to 92.70 lakh metric tonnes of rice) is also available in the Central Pool.
- It takes the total rice stock to 314.57 lakh metric tonnes.
Topic 6 : Developed countries to overshoot carbon emissions goal
Why in news: Developed countries — responsible for three-fourths of existing carbon emissions — will end up emitting 38% more carbon in 2030 than they have committed to, going by current trajectories, shows a study.
- The study comes ahead of the 28th Conference of Parties (COP-28) of the UN Framework Convention on Climate Change to be held in Dubai.
- It shows that 83% of this overshoot will be caused by the U.S., Russia, and the European Union.
- At COP-28, countries are expected to give an account of their Nationally Determined Contributions (NDCs), which are their commitments to the UN on emission cuts.
- In their NDCs, countries communicate actions they will take to reduce their greenhouse gas emissions in order to reach the goals of the Paris Agreement.
- Countries also communicate in their NDCs actions they will take to build resilience to adapt to the impacts of climate change.
- The study noted that the NDCs of developed countries already fall short of the global average reduction of emissions to 43% below 2019 levels that is needed to keep temperatures from rising above 1.5 degrees Celsius.
- Instead, developed countries’ collective NDCs only amount to a 36% cut.
Efforts against global warming:
- Decades of negotiations have obliged developed countries to lead global efforts to reduce greenhouse gas emissions with legally binding targets.
- Collectively, developed countries were to reduce emissions by 5% from their 1990 levels between 2008 and 2012, and by 18% during 2013 to 2020.
- Several countries have committed to achieving net zero carbon emissions by 2050.
- Doing so would require steady measurable cuts every decade until that year.
- As an intermediate objective, countries presented data to the UN on their projected cuts until 2030.
- To keep temperatures below 1.5 degrees Celsius, developed countries need to cut emissions to 43% below their 2019 level.
- However, the study found that based on their current emissions trajectories, their cuts would likely amount to only 11% by 2030.
- Except for two countries — Belarus and Norway — none of the developed countries seem to be on the path to meet their 2030 targets.
- Though Japan and Kazakhastan are close, and are expected to miss their targets by only a single percentage point.
Topic 7 : The expansion of settlements into flood-prone areas
Why in news: According to a study led by the World Bank, flood risk in many cities is rising because they are expanding into flood-prone areas.
- According to the paper, since 1985, human settlements in flood-prone areas have more than doubled.
- The findings spotlight the risk of unsustainable urbanisation in India.
- The study also found that middle-income countries like India have more urban settlements in flood-prone zones than low- and high-income countries.
How is India at risk?
- India isn’t among the 20 countries whose settlements are most exposed to flood hazards, but it was the third highest contributor to global settlements, after China and the U.S..
- It is also third after China and Vietnam among countries with new settlements expanding into flood-prone areas, all from 1985 to 2015.
- This means India is at significant risk of flood-related problems that could worsen in the coming years if the country wasn’t careful.
Bengaluru as an example:
- The Bengaluru floods cost the city ₹225 crore.
- In 1901-2022, the city’s population grew from around 1.6 lakh to more than a crore.
- To accommodate these people, the city expanded — but new localities overlooked the local topography.
Who are most affected?
- The risks are disproportionately higher for those living in informal structures.
- The geography of environmental risk is also the geography of informal low-income housing.
- Informal housing in cities is on land that is vacant and less desirable, so that they are not immediately driven off, so they often lie in low-lying, flood-prone areas.
Why cities expand in flood prone areas:
- Lack of governance:
- An important reason why urbanisation has expanded into flood-prone areas is that we don’t have the governance processes to look that this kind of development is environmentally unsustainable.
- When environmental regulations are applied to new constructions, they are often applied only to big infrastructure projects and not to medium- and small-scale modifications of localities.
- This contradicts the notion that certain localities are more flood-prone and that flooding and flood-risk are locality-level issues.
- Violation of laws:
- People commonly violate existing government regulations.
- a rise in eco-tourism resorts on forest land
- the construction of large structures, including government buildings
- religious structures, on rivers’ floodplains.
- As cities continue to expand, we can no longer avoid expanding into flood-prone areas.
- Market forces tend to push expansion into flood-prone areas.
- But recognising what these areas are and that we are actually expanding into them is the first step towards sustainable urban planning that addresses the risks.
- Some forms of adaptation are necessary, and they need to differentiate between low-income residents and unauthorised structures erected for the elite.
- Every city needs to do a proper scientific mapping of the flood prone areas.
- Urban governments need to make housing in such areas more flood-resilient and protect low-income housing.
- Some examples can be adapted such as riverside settlements that use stilt houses, like those used by the Mishing and the Miyah communities along the Brahmaputra.Topic 8 : Xerography
Why in news: Xerographic machines are in ubiquitous use around the world today to quickly and cheaply reproduce printed material
What is photocopying?
- Broadly, photocopying is a set of techniques used to duplicate content using, among other things, light.
- However, the contemporary colloquial use of the word ‘photocopying’ refers almost exclusively to xerography.
- Both the word ‘xerography’ and the name ‘Xerox’ come from the Greek root-word ‘xero’, meaning ‘dry’.
- This is because xerography is a type of photocopying method where the process doesn’t involve messy liquid chemicals.
Basic elements of xerography:
- A photoconductive surface:
- The first is the photoconductive surface — a surface coated with a photoconductive material.
- Such a material, when exposed to light, allows electrons to flow through it (that is it conducts electricity) but blocks them when it’s dark.
- This surface is negatively charged by placing a thin negatively charged wire with a high voltage next to it.
- Then, the sheet of paper to be copied is illuminated with a bright light.
- The darker parts of the paper don’t reflect the light whereas the unmarked parts do.
- This reflected light is carried by lenses and mirrors to fall on the photoconductive surface.
- In the parts of the surface where light falls, the photoconducting material will become conductive and allow the electrons near its surface to dissipate downwards (into a grounding).
- So the parts that remain negatively charged at the end of this step will correspond to parts of the paper-to-be-copied (TBC) where something was printed.
- Application of toner:
- A powdery substance called toner is applied to the surface.
- The toner is positively charged, so it will settle where negative charge persists on the surface.
- The surface then transfers the pattern of the toner on it to a sheet of paper.
- The paper has a stronger negative charge that causes the toner to jump.
- The final result:
- The toner is heated so that it melts and fuses with the paper.
- This is the paper that rolls out of the photocopying machine, the whole process having been completed in a few seconds.
- In practice, a rotating drum is used instead of a flat surface, and the paper TBC is illuminated by a flashing or stroboscopic light or a moving scanner.
Who invented xerography?
- An American attorney named Chester F. Carlson came up with a rudimentary version of xerography by 1938.
- Seven years later, he sold his idea to a non-profit organisation called the Battelle Memorial Institute in Ohio, where researchers refined the technique.
- A year later, in 1946, Haloid Photographic Company purchased a licence from Battelle to build a machine based on the technique.
- The company trademarked the name for this machine as the “Xerox machine” in 1948 and availed the first model for sale in 1949.
- Haloid’s managers were responsible for coining the word ‘xerography’, replacing Carlson’s ‘electrophotography’.