Rain at the highest point on Greenland for the first time

About Greenland

• Greenland is the world's largest island, located between the Arctic region and Atlantic oceans, east of the Canadian Arctic Archipelago.
• Greenland's highest mountain Mt. Gunnbjörn is also the highest peak located north of the Arctic Circle. Therefore, it does not just hold the title of being the highest peak in Greenland but is also the highest peak in the Arctic (3694 m/12120 ft).
• Greenland is an autonomous territory within the Kingdom of Denmark.
• Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe (specifically Norway and Denmark, the colonial powers) for more than a millennium, beginning in 986.
• The majority of its residents are Inuit, whose ancestors migrated from Alaska through Northern Canada, gradually settling across the island by the 13th century.
• Today, the population is concentrated mainly on the southwest coast, while the rest of the island is sparsely populated. Greenland is divided into five municipalities – Sermersooq, Kujalleq, Qeqertalik, Qeqqata, and Avannaata.
• It has two unincorporated areas – the Northeast Greenland National Park and the Thule Air Base. The latter, while under Danish control, is administered by the United States Air Force.
• Three-quarters of Greenland is covered by the only permanent ice sheet outside of Antarctica.
• With a population of 56,081 (2020), it is the least densely populated region in the world.
• About a third of the population lives in Nuuk, the capital and largest city; the second-largest city in terms of population is Sisimiut, 320 kilometres (200 mi) north of Nuuk.
• The Arctic Umiaq Line ferry acts as a lifeline for western Greenland, connecting the various cities and settlements.
• Greenland contains the world's largest and northernmost national park, Northeast Greenland National Park (Kalaallit Nunaanni Nuna eqqissisimatitaq).
• In 1979, Denmark granted home rule to Greenland; in 2008, Greenlanders voted in favour of the Self-Government Act, which transferred more power from the Danish government to the local Greenlandic government.
• Under the new structure, Greenland has gradually assumed responsibility for policing, the judicial system, company law, accounting, auditing, mineral resource activities, aviation, law of legal capacity, family law and succession law, aliens and border controls, the working environment, and financial regulation and supervision.
• The Danish government still retains control of monetary policy and foreign affairs including defence.
• At 70%, Greenland has one of the highest shares of renewable energy in the world, mostly coming from hydropower.

Why in news?

• Rain fell at the highest point on the Greenland ice sheet last week for the first time on record, another worrying sign of warming for the ice sheet already melting at an increasing rate.
• “That's not a healthy sign for an ice sheet,” said Indrani Das, a glaciologist with Columbia University's Lamont-Doherty Earth Observatory. “Water on ice is bad... It makes the ice sheet more prone to surface melt.”
• Not only is water warmer than the usual snow, it is also darker – so it absorbs more sunlight.
• This meltwater is streaming into the ocean, causing sea levels to rise. Already, melting from Greenland's ice sheet – the world's second-largest after Antarctica's – has caused around 25% of global sea level rise seen over the last few decades, scientists estimate. That share is expected to grow, as global temperatures increase.

Largest floating solar PV Project at Vishakhapatnam

• The National Thermal Power Corporation (NTPC ) Ltd, has commissioned the largest floating solar PV project of 25MW on the reservoir of its Simhadri thermal station in Visakhapatnam, Andhra Pradesh.
• This is also the first solar project to be set up under the Flexibilisation Scheme, notified by the Government of India in 2018.
• The Solar PV project was inaugurated today by Shri Sanjay Madan, RED (WR2 & SR), NTPC.
• The floating solar installation which has a unique anchoring design is spread over 75 acres in an RW reservoir. This floating solar project has the potential to generate electricity from more than 1 lakh solar PV modules.
• This would not only help to light around 7,000 households but also ensure at least 46,000 tons of CO2e are kept at arm’s length every year during the lifespan of this project.
• The project is also expected to save 1,364 million litres of water per annum. This would be adequate to meet the yearly water requirements of 6,700 households.
• The 2000MW coal-based Simhadri Station is the first power project to implement an open sea intake from the Bay of Bengal which has been functional for more than 20 years.
• NTPC is also planning to set up a hydrogen-based microgrid system on a pilot basis at Simhadri.
• With a total installed capacity of 66900 MW, NTPC Group has 71 Power stations including 29 Renewable projects. NTPC has set a target to install 60 gigawatts (GW) of renewable energy (RE) capacity by 2032. NTPC is also India's first energy company to declare its energy compact goals as part of the UN High-level Dialogue on Energy (HLDE).
• The group has over 17 GW of capacity under construction, including 5 GW of renewable energy projects. Uninterrupted supply of electricity through environment-friendly energy projects at affordable prices has been the hallmark of NTPC.

Why in News? Earthquake Observatories in India

• India is going to have 35 more earthquake Observatories by end of this year and 100 more such Observatories in the next five years.
• In the last six and a half decades since Independence, the country had only 115 Earthquake Observatories but now, there is going to be a quantum leap in the number of Earthquake Observatories in the country.
• The Indian subcontinent is considered one of the world's most disaster-prone areas in terms of earthquakes, landslides, cyclones, floods, and tsunamis.

What is an Earthquake?

• An earthquake is a fault that is a sharp break in the crustal rocks. When lithospheric plates move, the surface of the Earth vibrates (release of Energy and the Energy waves travel in all directions). An earthquake is the sudden release of the Energy in the Earth’s crust that creates seismic waves.
• The energy accumulation site is identified w deformed rocks caused by tension or compression.
• The subterranean spot at which rocks begin to shift/rupture is the Focus or Hypocenter of Earthquake, whereas the point vertically over the Focus is Epicenter, which experiences the 1st waves and the greatest damage which decreases as we go outwards.
• The waves generated by an Earthquake are called seismic waves recorded by an instrument Seismograph. The magnitude (Energy that is released) of the Earthquake is measured by Richter Scale whereas the intensity (Damage caused) is measured by Mercalli Scale.
• During Earthquake, the rocks in the path of P waves get compressed/ expanded in the direction of propagation so it affects their volume rather than shape. In the case of S waves, it changes the shape and not volume.
• Earthquakes are by far the most unpredictable and highly destructive of all-natural disasters due to their suddenness. Earthquakes that are of tectonic origin have proved to be the most devastating and their area of influence is also quite large than other causes.

Causes of Earthquakes

• Plate Movements: Ex. The Himalayan region has C-C convergence.
• Faulting and Folding: Ex. Bhuj & Latur earthquake.
• Volcanic Eruptions.
• Gaseous Expansion and Contraction inside the Earth
• Hydrostatic pressure (Ex. Reservoir induced) Ex. Koyna Dam Earthquakes in MH.
• Anthropogenic Causes: Mining & drilling.

Types of Earthquakes

• Tectonic EQs: Most common. Generated due to sliding of rocks along fault lines.
• Volcanic EQs: A special class of Tectonic EQ confined to the areas of volcanoes.
• Induced EQs: Occurs in the areas of large reservoirs.

Distribution of Earthquakes in the World

• The World's distribution of Earthquakes coincides very closely with that of volcanoes.
• ~70% of Earthquakes occur in the Circum Pacific belt. ~20% occur in the Meditteranean- Himalayan belt including Asia Minor, Himalayas and parts of Northwest China. Elsewhere Earth's crust is relatively stable and is less prone but not immune to earth tremors.

Earthquake-prone areas in India

• The entire region covering fourteen states (located in western and central Himalayas, northeast, and parts of the Indo-Gangetic basin) is highly prone to earthquakes.
• Some of the most vulnerable states are J&K, HP, UK, SK and Darjeeling, all NE states.
• The hilly regions are also prone to earthquake-induced landslides. The other seismically active regions of the country include the Gulf of Khambhat and Rann of Kutch in Western Gujarat (1819, 1956, 2001), parts of peninsular India like MH (1967, 1993), the islands of LD and A&N.

Impacts of Earthquake

1) Impact on the ground:

• Slope instability and Landslides or Avalanches (often cause obstructions in the flow of rivers and channels resulting in the formation of reservoirs).
• Liquefaction, Fires in some areas, Deformation on ground surface.
• Fissures on the upper layers of the earth’s crust through which water and other volatile materials gush out, inundating the neighbouring areas.
• Sometimes, rivers also change their course causing floods and other calamities in the affected areas.

2) Impact on

• manmade infrastructure: Damage to settlements, infra, industries.
• On the water: Flash floods, Tsunamis (waves generated by tremors and not an EQ), Hydro-Dynamic Pressure.
• On Biodiversity: Loss of human and animal lives, Robs the population of their material and socio-cultural gains that they have preserved over generations. It renders them homeless, and unemployed, and increases poverty.

Earthquake Disaster Management:

• In our present state of knowledge, earthquakes can neither be prevented nor predicted in terms of their magnitude, or place and time of occurrence. Also, unlike other disasters, the damages caused by them are more devastating.

• So, the most effective measures of risk reduction are pre-disaster mitigation, preparedness & preventive measures. Since it also destroys transport and communication links, providing timely relief to the victims becomes difficult. Hence the above methods should be combined w expeditious & effective rescue and relief actions immediately after the occurrence of the earthquake.
• Establishing earthquake monitoring centres for regular monitoring and fast dissemination of information among the people in the vulnerable areas. The use of GPS can be of great help in monitoring the movement of tectonic plates.
• Preparing a vulnerability map of the country and dissemination of vulnerability risk information among the people.
• Educating the people about the ways and means of minimizing the adverse impacts of disasters.
• Modifying the house types and building designs in the vulnerable areas and discouraging the construction of high-rise buildings, large industrial establishments and big urban centres in such areas.
• Finally, making it mandatory to adopt earthquake-resistant designs and use light materials in major construction activities in vulnerable areas.

Nuclear Fusion Energy

What is Nuclear Fusion?

• Fusion is the energy source of the Sun and stars. In the tremendous heat and gravity at the core of these stellar bodies, hydrogen nuclei collide, fuse into heavier helium atoms and release tremendous amounts of energy in the process.
• Nuclear fusion is defined as the combining of several small nuclei into one large nucleus with the subsequent release of huge amounts of energy. Nuclear fusion powers our sun and harnessing this fusion energy could provide an unlimited amount of renewable energy.
• Twentieth-century fusion science identified the most efficient fusion reaction in the laboratory setting to be the reaction between two hydrogen isotopes, deuterium (D) and tritium (T).
• The DT fusion reaction produces the highest energy gain at the "lowest" temperatures.
• Three conditions must be fulfilled to achieve fusion in a laboratory:
  1. Very high temperature (on the order of 150,000,000° Celsius);
  2. Sufficient plasma particle density (to increase the likelihood that collisions do occur); and
  3. Sufficient confinement time (to hold the plasma, which has a propensity to expand, within a defined volume).
• At extreme temperatures, electrons are separated from nuclei and a gas becomes a plasma—often referred to as the fourth state of matter. Fusion plasmas provide the environment in which light elements can fuse and yield energy.
• In a tokamak device, powerful magnetic fields are used to confine and control the plasma.

So how exactly does nuclear fusion work?

• Simply put, nuclear fusion is the process by which two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.
• Fusion reactions take place in a state of matter called plasma — a hot, charged gas made of positive ions and free-moving electrons that has unique properties distinct from solids, liquids and gases.
• To fuse on our sun, nuclei need to collide with each other at very high temperatures, exceeding ten million degrees Celsius, to enable them to overcome their mutual electrical repulsion.
• Once the nuclei overcome this repulsion and come within a very close range of each other, the attractive nuclear force between them will outweigh the electrical repulsion and allow them to fuse.
• For this to happen, the nuclei must be confined within a small space to increase the chances of collision.
• In the sun, the extreme pressure produced by its immense gravity create the conditions for fusion to happen.
• The amount of energy produced from fusion is very large — four times as much as nuclear fission reactions — and fusion reactions can be the basis of future fusion power reactors.
• Plans call for first-generation fusion reactors to use a mixture of deuterium and tritium — heavy types of hydrogen.
• In theory, with just a few grams of these reactants, it is possible to produce a terajoule of energy, which is approximately the energy one person in a developed country needs over sixty years.
• While the sun’s massive gravitational force naturally induces fusion, without that force a higher temperature is needed for the reaction to take place.
• On earth, we need temperatures exceeding 100 million degrees Celsius and intense pressure to make deuterium and tritium fuse, and sufficient confinement to hold the plasma and maintain the fusion reaction long enough for a net power gain, i.e. the ratio of the fusion power produced to the power used to heat the plasma.
• Nuclear fusion and plasma physics research are carried out in more than 50 countries, and fusion reactions have been successfully achieved in many experiments, albeit without demonstrating a net fusion power gain.

Historical Background for collaborations

• Ever since nuclear fusion was understood in the 1930s, scientists have been on a quest to recreate and harness it. Initially, these attempts were kept secret. However, it soon became clear that this complex and costly research could only be achieved through collaboration.
• At the second United Nations International Conference on the Peaceful Uses of Atomic Energy, held in 1958 in Geneva, Switzerland, scientists unveiled nuclear fusion research to the world.

Role of International Atomic Energy Agency (IAEA)

• The IAEA has been at the core of international fusion research. The IAEA launched the Nuclear Fusion journal in 1960 to exchange information about advances in nuclear fusion, and it is now considered the leading periodical in the field.
• The first international IAEA Fusion Energy Conference was held in 1961 and, since 1974, the IAEA convenes a conference every two years to foster discussion on developments and achievements in the field.

International Thermonuclear Experimental Reactor (ITER)

• After two decades of negotiations on the design and location of the world’s largest international fusion facility, ITER was established in 2007 in France, with the aim of demonstrating the scientific and technological feasibility of fusion energy production.
• In southern France, 35 nations* are collaborating to build the world's largest tokamak, a magnetic fusion device that has been designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy based on the same principle that powers our Sun and stars.
• ITER will be the first fusion device to produce net energy. ITER will be the first fusion device to maintain fusion for long periods of time.
• And ITER will be the first fusion device to test the integrated technologies, materials, and physics regimes necessary for the commercial production of fusion-based electricity.
• Thousands of engineers and scientists have contributed to the design of ITER since the idea for an international joint experiment in fusion was first launched in 1985.
• The ITER Members—China, the European Union, India, Japan, Korea, Russia and the United States—are now engaged in a 35-year collaboration to build and operate the ITER experimental device, and together bring fusion to the point where a demonstration fusion reactor can be designed.

• What will ITER do?
  1. Produce 500 MW of fusion power
  2. Demonstrate the integrated operation of technologies for a fusion power plant
  3. Achieve a deuterium-tritium plasma in which the reaction is sustained through internal heating
  4. Test tritium breeding
  5. Demonstrate the safety characteristics of a fusion device.
• ITER's First Plasma is scheduled for December 2025. That will be the first time the machine is powered on, and the first act of ITER's multi-decade operational program.

What are the effects of fusion on the environment?

• Fusion is among the most environmentally friendly sources of energy.
• There are no CO2 or other harmful atmospheric emissions from the fusion process, which means that fusion does not contribute to greenhouse gas emissions or global warming.
• Its two sources of fuel, hydrogen and lithium, are widely available in many parts of the Earth.
• Nuclear fusion is a clean and green route to producing energy, as it does not involve any remnant radioactive waste products. Fusion reactions power hydrogen bombs. However, so far, fusion devices that show a net energy gain have not been demonstrated in labs.

What’s the difference between nuclear fission and nuclear fusion?

• Both are nuclear processes, in that they involve nuclear forces to change the nucleus of atoms.
• Chemical processes on the other hand involve mainly electromagnetic force to change only the electronic structure of atoms.
• Fission splits a heavy element (with a high atomic mass number) into fragments; while fusion joins two light elements (with a low atomic mass number), forming a heavier element.
• In both cases, energy is freed because the mass of the remaining nucleus is smaller than the mass of the reacting nuclei.
• The reason why opposite processes release energy can be understood by examining the binding energy per nucleon curve. Both fusion and fission reactions shift the size of the reactant nuclei towards higher bounded nuclei.

Does Fusion produce radioactive nuclear waste the same way fission does?

• Nuclear fission power plants have the disadvantage of generating unstable nuclei; some of these are radioactive for millions of years.
• Fusion on the other hand does not create any long-lived radioactive nuclear waste.
• A fusion reactor produces helium, which is an inert gas.
• It also produces and consumes tritium within the plant in a closed circuit. Tritium is radioactive (a beta emitter) but its half life is short. It is only used in low amounts so, unlike long-lived radioactive nuclei, it cannot produce any serious danger.
• The activation of the reactor’s structural material by intense neutron fluxes is another issue.
• This strongly depends on what solution for blanket and other structures has been adopted, and its reduction is an important challenge for future fusion experiments.

Can fusion cause a nuclear accident?

• No, because fusion energy production is not based on a chain reaction, as is fission.
• Plasma must be kept at very high temperatures with the support of external heating systems and confined by an external magnetic field.
• Every shift or change of the working configuration in the reactor causes the cooling of plasma or the loss of its containment; in such a case, the reactor would automatically come to a halt within a few seconds, since the process of energy production is arrested, with no effects taking place on the outside.
• For this reason fusion reactors are considered to be inherently safe.

Can fusion reactors be used to produce weapons?

• No. Although hydrogen bombs do use fusion reactions, they require an additional fission bomb to detonate.
• Working conditions of a magnetically-confined fusion reactor require a limited amount of fuel in the reactor.
• This fuel is continuously injected and consumed; therefore there is never a sufficient amount of fuel to produce the instantaneous power required for a weapon.

Why in news? U.S. lab makes headway in nuclear fusion energy

• An experiment at the U.S. National Ignition Facility (NIF), within the Lawrence Livermore National Laboratory, Livermore, California, comes close to demonstrating this. In this lab, using laser beams, tiny pellets of deuterium and tritium (heavier isotopes of hydrogen) have been fused to form helium and release energy that very nearly matches the amount of energy input using the lasers.
• The NIF has been trying to achieve this for nearly a decade. Now, the experiment has produced a yield that almost equals the laser energy input. To be functional, a reactor has to produce an output that is at least tens of times the input energy.
• A tiny pellet of the fuel (deuterium and tritium) is placed in a cylidrical thumbnail-sized vessel, known as a hohlraum that has holes on both faces. A total of 192 laser beams are directed through the holes to strike the walls of the hohlraum. This causes the hohlraum to emit x-rays which, in turn, impinge on the pellet and compress it. The heated core of the pellet reaches 100 million degrees temperature which starts the fusion reactions. Further, the pellet has to “ignite” and only then can it reach the stage of becoming a microbomb – a deuterium-tritium fusion reactor – and release energy that can be tapped.

Laser facility

• The laser facility itself occupies a large area, equal to nearly three cricket fields, and the lasers can deliver up to 500 terawatts of power using its 192 individual laser beams. This is focused into the openings in the hohlraum which contains the pellet measuring some 2-3 mm.
• “The amount of laser energy used in these experiments is quite modest, 1.9 megajoule (MJ). This is approximately equal to the energy it takes to heat a large pot (8 litres) of water by 100 degrees Celsius. The amount of fusion energy produced in these experiments was approximately 1.3 MJ which is now for the first time comparable to amount of laser energy input.
• This is the first time, in a controlled laboratory setting, that an inertial fusion system (another name for a laser driven fusion system) has produced nearly as much energy was supplied to initiate the reaction.
• If we do the energy accounting we estimate that the fusion energy production is approximately 5 times the amount of energy coupled from the laser to target.

Tremendous progress

• To make a fusion reactor, hundreds of pellet implosions have to happen per second and means have to be found to extract the neutron energy as heat and produce electricity. This [experiment] is far from that stage, but the researchers have made tremendous progress in the last decade.
• Several steps remain before a viable nuclear fusion reactor can be realised. Ignition, or energy break-even must be achieved.
• Many laser pulses must be made to act per second to increase the net yield to a sufficiently high value. Then the technology to convert the neutron energy into electricity has to be developed.
• The fusion energy produced is released in an incredibly short amount of time, approximately, 90 picoseconds producing close to 15 petawatts of power. This is approximately equivalent to some recent estimates of the total world power consumption, however the experiment only produces this power for an incredibly short period of time, whereas power is consumed continuously across the world.”

How was the new breakthrough achieved?

• The team used new diagnostics, improved laser precision, and even made changes to the design. They applied laser energy on fuel pellets to heat and pressurise them at conditions similar to that at the centre of our Sun. This triggered the fusion reactions.
• These reactions released positively charged particles called alpha particles, which in turn heated the surrounding plasma. (At high temperatures, electrons are ripped from atom’s nuclei and become a plasma or an ionised state of matter. Plasma is also known as the fourth state of matter)
• The heated plasma also released alpha particles and a self-sustaining reaction called ignition took place. Ignition helps amplify the energy output from the nuclear fusion reaction and this could help provide clean energy for the future.
• On August 8, the team noted an energy output of more than 1.3 megajoules. The findings are yet to be published in a peer-reviewed journal.

UK hatches plan to build world's first fusion power plant

• In June, JET will begin fusing even quantities of tritium and deuterium, another isotope of hydrogen. It is this fuel mix that ITER will use in its attempt to create more power from a fusion reaction than is put in — something that has never before been demonstrated. The reactor should heat and confine a plasma of deuterium and tritium such that the fusion of the isotopes into helium produces enough heat to sustain further fusion reactions.

Institute of Plasma Research, India

• The Institute for Plasma Research (IPR) was established in 1986 as an autonomous R&D institute under the Department of Science and Technology (DST) with a mandate to pursue research in plasma science and technology. The institute grew rapidly and came under the administrative umbrella of the Department of Atomic Energy (DAE) in 1995.
• This institute is largely involved in theoretical and experimental studies in plasma science including basic plasma physics, magnetically confined hot plasmas and plasma technologies for industrial application.
• The institute owns two operational tokamaks (a machine for controlling thermonuclear fusion) - ADITYA and Steady State Tokamak (SST)-1.
• FCIPT, ITER-India and CPP-IPR, located in Gandhinagar and Guwahati are three divisions under IPR.

Aditya Tokamac in India

• ADITYA is the first indigenously designed and built tokamak of the country. It was commissioned in 1989.
• ADITYA, a medium size Tokamak, is being operated for over a decade. It has a major radius of 0.75m and minor radius of the plasma is 0.25 m.
• A maximum of 1.2 T toroidal magnetic field is generated with the help of 20 toroidal field coils spaced symmetrically in the toroidal direction. The major subsystems and parameters of the machine have been described elsewhere.
• ADITYA is regularly being operated with the transformer-converter power system. ~100 msec 80 - 100 kA plasma discharges at toroidal field of 8.0 kG are being regularly studied.
• During this period experiments on edge plasma fluctuations, turbulence and other related works have been conducted. Standard diagnostics have been employed during these measurements.

Steady State Superconducting Tokamac

• A steady state superconducting tokamak SST-1 is under design and fabrication at the Institute for Plasma Research.
• The objectives of SST-1 include studying the physics of the plasma processes in tokamak under steady state conditions and learning technologies related to the steady state operation of the tokamak.
• These studies are expected to contribute to the tokamak physics database for very long pulse operations.
• The SST-1 tokamak is a large aspect ratio tokamak, configured to run double null diverted plasmas with significant elongation (k) and triangularity (d).
• The specific objective of the SST-1 project is to produce 1000 s elongated double null divertor plasma.There are several conventional questions in tokamak physics, which will be addressed again in steady state scenario.
• Some of these are related to the energy, particle and impurity confinement, the effect of impurities and edge localized modes (ELM) in steady on energy confinement, the stability limits and their dependence on current drive methods, the resistive tearing activities in presence of RF fields, disruptions and vertical displacement events (VDE), and thermal instability.

Way Forward

• It is expected that fusion could meet humanity’s energy needs for millions of years. Fusion fuel is plentiful and easily accessible: deuterium can be extracted inexpensively from seawater, and tritium can be produced from naturally abundant lithium.
• Future fusion reactors will not produce high activity, long lived nuclear waste, and a meltdown at a fusion reactor is practically impossible.
• Importantly, nuclear fusion does not emit carbon dioxide or other greenhouse gases into the atmosphere, and so along with nuclear fission could play a future climate change mitigating role as a low carbon energy source.