Why in News?

• Mohe, China’s northernmost city, recorded a temperature of minus 53^oC this week. That was the coldest in its recorded history.
• Scientists say Asia’s extreme cold is largely the result of the Polar Vortex phenomenon.

What’s in today’s article?

• About Polar Vortex (Meaning, how it works, Relation w.r.t. Climate Change, etc.)
• News Summary

What is a Polar Vortex?

• The polar vortex is a large area of low pressure and cold air surrounding both of the Earth’s poles.
• It always exists near the poles, but weakens in summer and strengthens in winter.
• The term “vortex” refers to the anti-clockwise flow of air that helps keep the colder air near the Poles.
• Many times, during winter in the northern hemisphere, the polar vortex will expand, sending cold air southward with the jet stream.
  • Jet stream is the area of fast-moving air high in the atmosphere that surrounds the polar vortex.
• This occurs regularly during wintertime and is often associated with large outbreaks of Arctic air in the United States & Canada.
• Portions of Europe and Asia also experience cold surges connected to the polar vortex.

Is it a new Climatic Phenomenon?

• Polar vortexes are not something new.
• The term “polar vortex” has only recently been popularized, bringing attention to a weather feature that has always been present.
• By itself, the only danger to humans is the magnitude of how cold temperatures will get when the polar vortex expands, sending Arctic air southward into areas that are not typically that cold.

Relation w.r.t. Climate Change:

• The polar vortex is held in place by the Earth’s rotation and temperature differences between the Arctic and mid-latitudes.
• Changes in temperature differences can make the polar vortex expand to more southern latitudes.
• While this phenomenon occurs naturally, climate change is expected to impact the frequency and severity of polar vortex events.

News Summary:

• China’s national weather agency issued daily warnings of extremely cold temperatures recently for almost the entire country.
• On the Korean Peninsula, North Korea’s state meteorological agency warned residents in the last week of “the most bitter cold wave in 23 years”. And in South Korea, hundreds of flights were grounded, and beaches were covered in ice.
• Scientists say Asia’s extreme cold is largely the result of the Polar Vortex phenomenon.
• The term refers to an expanse of cold air that generally circles the Arctic but occasionally shifts south from the North Pole.

Why in news?

Japan is expected to start flushing 1.25 million tonnes of wastewater from the embattled Fukushima nuclear power plant into the Pacific Ocean this year, as part of a $76-billion project to decommission the facility.

What is the issue about?

• Reactor buildings at the Fukushima power plant (Japan) were damaged by hydrogen explosions caused by an earthquake and tsunami in 2011.
• More than a million tonnes of water have been used to cool the melted reactors.
• Currently, the radioactive water is treated in a complex filtration process that removes most of the radioactive elements, but some remain, including tritium – deemed harmful to humans only in very large doses.
• The plant’s operator Tokyo Electric Power Co (TepCo) is running out of space, with these tanks expected to fill up by 2022.
• Japan has approved a plan to release the contaminated water from the damaged Fukushima nuclear plant into the Pacific Ocean.
• The water will be treated and diluted so radiation levels are below those set for drinking water.

What are the concerns with this move?

• No threshold level – There is no known threshold below which radiation can be considered safe.
• Health impacts – Any discharge of radioactive materials will increase the risk of cancer and other known health impacts to those who are exposed.
• Effect on marine resource – Experts expect the affected water to poison the fish.
  • South Korea banned seafood imported from around Fukushima from 2013.

• Presence of radionuclides – TEPCO hasn’t removed tritium from the water. Tritium is easily absorbed by the bodies of living creatures and rapidly distributed via blood.
• In 2018, it was reported that there were other radionuclides including isotopes of ruthenium and plutonium in the treated water that could persist for longer in the marine creatures and on the seafloor.
• Reputation – Ultimately, Japan is also concerned about its reputation.

In Japan, the nuclear accidents reduced nuclear power’s contribution to electricity generation from 30% before 2011 to 5% in 2022. But the government has articulated plans to restart older reactors and build new ones to cut the increasing fossil fuels cost.

What options do Japan have in managing the waste water?

• Longer storage – The Japanese government can store the water for longer and then discharge it as tritium’s half-life (time it takes for its quantity to be halved through radioactive decay) is 12-13 years.
• The quantity of any other radioactive isotopes present in the water will also decrease in this time so that the water could be less radioactive at the time of discharge.
• Tanks in uninhabitable land – The tanks to hold the water can be situated in the land around the Fukushima facility which was declared to be uninhabitable by the Japanese government.
• Discharge into the sea – In 2020, International Atomic Energy Agency (IAEA) officials said the discharge would be technically feasible and would allow the timeline objective to be achieved.

Why in news?

With the sinking of Joshimath town, there is a considerable amount of research on the vulnerabilities of Himalayan geology brought to the fore.

How vulnerable is the Himalayan range?

• The Himalaya is a fragile mountain range that is still rising as the Indian plate continues to push into the Asian plate.
• The mountains are mainly the shale upwelling of the sea, which makes them quite unstable.
• In fact, they are largely held together by the forests that they support.

What is the case of Joshimath crisis?

• Geography – At over 6,000 feet, Joshimath sits on the side of an unstable ridge created largely from glacial moraine rock and shale in a rift valley.
• It is also a seismic zone.
• The ground beneath is a heterogeneous mass with pockets of variegated rock and open spaces occupied by water and mud from old glacial deposits.
• It also holds some important aquifers.
• Issues – Joshimath is no place for a tourist town that supports more than 2 million pilgrims a year or a four-lane highway.
• The government has sanctioned a hydropower project in the Dhauliganga-Alaknanda basin which upon tunneling punctured an aquifer in 2009 and contributed to the Joshimath slide.
• Uttarakhand state has more than 40,000 km of roads and counting today for tourists to visit the Char Dham sites (Yamunotri, Gangotri, Badrinath and Kedarnath).
• India also appears to be competing with China to build high-altitude railways.
• The mountains in Tibet on the Chinese side are made of firm rock whereas most of the Himalayan mountains are made of the unstable shale.

What are the concerns?

• Extreme weather events – With the consequent loss of forest cover and extreme weather events (the 2013 Kedarnath flood), catastrophes have occurred at a steady beat in all of Uttarakhand.
• Soil and water degradation – The local soil and water have been degraded.
• Decline in natural springs – The number of natural mineral water springs is declining.
• Increasing landslides – The number of landslides is also shooting up.

What lies ahead?

• If India needs any strategic border roads, they must run along rocky terrain to be stable.
• Those roads that exist on shale or other loose-soil hills must be urgently forested to stabilise the steep hillside as well as hold water and restore springs.
• There must be a complete ban on any hydroelectric power projects in the Himalaya, especially on the source-rivers of the Ganga (Bhagirathi and Alaknanda).
• Indian Himalaya has to be declared as an “inviolate protected zone” and a “planet reserve” similar to the declaration of Amazon basin as a “strictly protected zone”.

For the fourth year in a row, the world’s oceans recorded extreme heating in 2022 on account of anthropological activities.

• Ocean Heat Content (OHC) is the amount of energy absorbed by and stored in the oceans.
• OHC is measured in joules, the unit of energy.
• When sunlight reaches the earth, oceans absorb this energy and store it as heat.
• While the heat is first absorbed at the surface of the water body, some of it is eventually disbursed throughout.
• Water also has a higher heat capacity than air, which means that water heats up slower than air and can store much larger amounts of heat.

More than 90% of the excess heat accumulated in the earth’s climate is deposited in the oceans.

• Climate change and OHC – OHC is an important indicator of climate change.
• An increase in greenhouse gas emissions traps more energy from the sun in the atmosphere.
• Rising ocean temperatures strengthen the exchange of energy from oceans to the atmosphere by increasing the evaporation of water and thus the quantity of atmospheric moisture.
• This leads to changes in global precipitation patterns as well as temperatures.
• Stratification and salinity-contrast index, along with OHC, are important elements in quantifying climate change.
• Stratification – Vertical stratification happens when there is change in the density of water due to temperature and salinity changes in oceans.
• This stratification hinders water mixing and consequently the exchange of heat, carbon, oxygen and so on between layers.
• Salinity-contrast Index – Defined as the difference between the salinity averaged over climatologically high-salinity and low-salinity regions.
• Salinity-contrast index, an indicator of a change in the water cycle, reached its highest level on record in 2022.
• Salinity determines water density, which drives the circulation of water in oceans.

About Ken-Betwa Link Project:

• Under this, the transfer of excess water from the River Ken to the Betwa basin through the use of a concrete canal is proposed.
• It is the first project under the National Perspective Plan for the interlinking of rivers.
• It aims to provide irrigation to the Bundelkhand region, which is one of the worst drought-affected areas in India.
• A Tripartite Memorandum of Understanding was signed between the Centre and the governments of UP and MP for the project.
• Implementing Agency: A Special Purpose Vehicle (SPV) called Ken-Betwa Link Project Authority (KBLPA) will be set up to implement the project.
• The National Interlinking of Rivers Authority (NIRA) has the power to set up SPV for individual link projects.