Physical Geography

India extends continental-shelf claim in Arabian Sea

Context: India has strategically advanced its maritime interests by submitting a revised claim to the United Nations Commission on the Limits of the Continental Shelf (CLCS), seeking recognition for an additional 10,000 square kilometers of seabed in the Central Arabian Sea.

Relevance of the topic:

Prelims: Extended Continental Shelf; Commission on the Limits of the Continental Shelf; Location of Sir Creek.

Mains: India-Pakistan Bilateral Relations: Maritime disputes.

Continental Shelf and Extended Continental Shelf:

Continental shelf is a natural seaward extension of a land boundary. Coastal countries have an EEZ (exclusive economic zone) which gives exclusive mining and fishing rights, up to 200 nautical miles from their coastlines.
Extended Continental Shelf:
- States can make claims for more area in the ocean in the UN body Commission on the Limits of the Continental Shelf (CLCS), if they can scientifically establish that this claimed area extends unbroken from their landmass all the way till the sea bed.
- If proved, all of this oceanic area is considered part of a country’s extended continental shelf. This gives them rights to commercially mine for valuable minerals, polymetallic nodules and oil reserves.

India’s extended Maritime Claims

India has increased its claim in the Central Arabian Sea, as part of its ‘extended continental shelf’ by nearly 10,000 square km.
India has also modified an earlier claim to avoid a long-standing dispute with Pakistan over the maritime boundary between the two countries.
With the anticipated addition of approximately 1.2 million square km of extended continental shelf from the two submissions to the ~2 million sq. km of EEZ, India’s seabed and sub-seabed area would become almost equal to its land area of 3.274 million sq. km.

India’s Maritime Disputes

1. With Pakistan:

Sir Creek dispute: Sir Creek area is a 96-kilometer tidal estuary in the Indus River Delta. It serves as a boundary between India's Gujarat state and Pakistan's Sindh province. It is located near the marshy regions adjoining the Rann of Kutch.
2021: Pakistan objected to portions of India’s claimed territory in the Western offshore regions on the grounds that nearly 100 nautical miles overlapped with a maritime border that was under the Sir Creek dispute.
2023: CLCS rejected the entirety of India’s claim in the Arabian Sea region. However, the Commission gives leeway to countries to submit ‘modified claims.’
2025: India has split its original claim (in the Western Arabian Sea) into two ‘partial ones.’ This was done to ensure that India’s claim in the Central Arabian Sea region is not affected.

2. With Oman:

Some parts of India’s continental shelf claims in the Arabian Sea overlap with that of Oman.
However, the two countries have an agreement in place since 2010 that while the continental shelf between them is yet to be delimited, it is ‘not under dispute.’

3. On the Eastern and Southern coast:

India has claimed about 300,000 square km in the Bay of Bengal and the Indian Ocean though these have faced contests by Myanmar and Sri Lanka.
The CLCS is expected to begin a new session of consultations later this year.

Lapis Lazauli

Relevance of the Topic : Prelims: About lapis lazuli; Use in ancient civilisations (Indus Valley, Egyptian, European Renaissance).

About Lapis Lazuli

Deep blue metamorphic rock used as a semi-precious gemstone.
Valued for its colour and ornamental properties for over 6,000 years.

Geological Composition

Lapis lazuli is primarily composed of lazurite (25-40%), a feldspathoid silicate mineral that gives the rock its characteristic deep blue color.
Its blueness depends on the amount and structure of sulphur within lazurite.

Prevalence

Found in many countries so far, including Chile, Russia, and the US.
The highest quality rock comes from Afghanistan’s Badakhshan province, where it has been mined for more than 6,000 years.

Historical Significance and Uses

In ancient times, traders in India imported lapis lazuli from Badakhshan, perhaps as long ago as 1000 BC.
Ornamental lapis lazuli ornaments have been found in the remains of Indus Civilisation sites including Mohenjo-daro and Harappa.
Ancient Egyptians used lapis lazuli in jewellery, amulets, and as powdered eye makeup.
In the Renaissance period, artistes in Europe ground lapis lazuli down into ultramarine, an expensive pigment they used in their paintings.

Glacier Melting & Sea level Rise

Context: A newly published study highlights that melting ice from glaciers worldwide has led to the sea level rising by almost 2 cm this century alone.

Relevance of the Topic: Prelims: Key trends regarding climate change.

Major Highlights of the Study

Study: Community estimate of global glacier mass changes from 2000 to 2023.
Contributors: Scientists from the University of Edinburgh (Scotland) and the University of Zurich (Switzerland)

Findings:

Melting ice has led to the sea level rising by almost 2 cm this century alone.
Glaciers have been losing 273 billion tonnes of ice each year, equivalent to water Earth’s entire population would consume over a period of 30 years.

Glacial Melting and Sea Rise

According to the US agency National Oceanic and Atmospheric Administration (NOAA):
- The rate of glacial melting has doubled from 0.18 cm per year in 1993 to the current rate of 0.42 cm per year.
- The global sea level has risen by about 21-25 cm since 1880.
As per the National Aeronautics and Space Administration (NASA), global sea levels have risen by more than 10 cm between 1993-2024.
According to a World Meteorological Organisation report, sea level is not rising uniformly around the world (owing to local changes in ocean heat content and salinity). For example- the southwestern Indian Ocean region is seeing sea level rise at a rate of 2.5 mm per year, faster than the global average.

Indian Scenario

Data from the Center for Study of Science, Technology and Policy (CSTEP), Bengaluru.

Mumbai has witnessed a rise of 4.44 cm between 1987 and 2021, the worst among Indian cities.
West Bengal’s Haldia has witnessed a sea-level rise of 2.726 cm.
Andhra Pradesh’s Visakhapatnam has witnessed a sea-level rise of 2.381 cm.
Kerala’s Kochi has witnessed a sea-level rise of 2.213 cm.

Factors contributing to the Sea level Rise:

Sea level rise is essentially the increase in the average height of the ocean’s surface, measured from the centre of the Earth.

Global Warming: This has resulted in increased melting of land-based ice, such as glaciers and ice sheets. According to the latest study, since 2000, glaciers have lost between 2% and 39% of their ice regionally, and about 5% globally.
Thermal expansion of seawater: With global temperatures rising, oceans are becoming warmer, and as a result, the volume of water is increasing as well. According to the National Aeronautics and Space Administration (NASA) thermal expansion of seawater is responsible for one-third to half of global sea level rise.

Concerns associated with the rising sea levels

As per the study “Every centimeter of sea level rise exposes another 2 million people to annual flooding somewhere on our planet”.

Flooding and erosion of coastal areas:
- Sea level rise leads to more frequent and intense coastal flooding, which exacerbates coastal erosion.
- According to a 2018 report by the National Centre for Coastal Research (NCCR), between 1990 and 2016, the West Bengal coast alone lost almost 99 sq km of land.
More severe geophysical phenomenon:
- The rise results in more intense storm surges, allowing more water inland during tropical storms.
- This in turn can impact coastal ecosystems like mangroves, coral reefs and salt marshes, contaminate fresh water supplies etc.
Displacement of population:
- Submergence, erosion and intense climatic events may result in huge displacement of coastal populations, which in turn would adversely impact their livelihood and their age-old traditions.
- A 2024 study in the journal Scientific Reports found that 15% of the global; population lived merely 10 km away from water.
Changes in weather patterns: Addition of a considerable amount of freshwater into the ocean is concerning as this increase in freshwater has the potential to disturb the oceanic circulations, which is a crucial system of ocean currents responsible for shaping the Earth's climate and weather patterns.

Global Sea Ice Cover has dipped to Record Low

Context: As per the data from US National Snow and Ice data Center (NSIDC), the combined extent of Arctic and Antarctic sea ice dropped from 15.93 million sq km to 15.76 million sq km in marking a record low.

Relevance of the Topic: Prelims: Questions based on climate change and climatology.

About Sea Ice Cover

There are two major sea ice spots in the world, the Arctic and Antarctic. Arctic sea ice covers 40% of total global sea ice. Whereas, Antarctic sea ice accounts for 60% of total global sea ice due to its extensive seasonal fluctuation.
Role of sea ice in maintaining climate:
- Enhancing albedo: The white ice helps in reflecting back the insolation, enhancing albedo. This helps in maintaining the global temperature.
- Absorbing heat: The sea ice absorbs the subsurface heat in the ocean. This reduces the average ocean temperature.
- Prevents ocean acidification: By reducing the ocean temperature, sea ice cover helps in reducing the carbonification of ocean water. This in turn helps in maintaining health of corals, across the globe.

Extent of ice dip in Arctic and Antarctic (As per the study)

According to the NSIDC, an estimate of 77,800 sq km of ice has been lost per year since the late 1970s.
Arctic: Between 1981 and 2010, Arctic sea ice extent in September (when it reaches its minimum) shrunk at a rate of 12.2% per decade.
Antarctica: Until 2015, the region actually witnessed a slight year-on-year increase in sea ice. But, between late 2014 and 2017 the Antarctic lost two million square km of sea ice, i.e., an area equivalent to roughly four times the size of Spain.

Reasons behind the dip:

Oceanic and Atmospheric changes: The studies suggested the subsurface warming of the Southern Ocean has pushed the Antarctic sea ice melt.
Transformed wind pattern: Changes in the wind patterns can influence sea ice extent by pushing warmer water. The transformed wind pattern in the Arctic, sea ice remained low because of the delayed freezing around the Hudson Bay.
Increased ocean heat loss: Less ice means more open ocean, which accelerates further melting of ice, due to rise in absorption of heat.
Storms and higher air temperature: The regions like the Barent sea witnessed some storms due to which the Arctic ice has become thinner and more fragile over the years. Also, higher than usual air temperatures in areas such as Svalbard, Norway resulted in further loss of sea ice.

Implications of sea ice loss

Climate regulation: Antarctica sea ice plays a crucial role in regulating earth’s climate by reflection. A decrease in the sea ice alters these dynamics, potentially accelerating global warming.
Ecosystem impact: The loss of ice affects the habitat of various polar species (like Polar Bear and Penguins), disrupting food chains and threatening biodiversity.
Sea level rising: While sea ice melt does not directly contribute to sea level rise leading to further vulnerability and climate change induced migration. (E.g., Indonesia changed its capital from Jakarta due to the threat of sea level rise.)

Understanding the contributing factors for dip in ice cover and its potential consequences is essential for developing effective mitigation and adaptation strategies.

Earth’s Inner Core may have Changed Shape

Context: New research has suggested that the Earth's inner core may have undergone a significant transformation in its shape over the past two decades.

Relevance of the Topic:Prelims: Key facts about Internal Structure of Earth: Crust, Mantle and Core.

Internal Structure of Earth: Crust, Mantle and Core

The structure of Earth is divided into four major components: Crust, Mantle, Outer core, inner core.
Each layer has a unique chemical composition, physical state, and can impact life on Earth's surface.

LAYERS OF EARTH

1. CRUST

It is the outermost solid part of Earth and is brittle in nature.
Average density of outer and lower crust is 2.7 and 3.0, respectively.
Oceanic crust is thinner (5 Km) as compared to continental crust (30 Km)
Continental crust is thicker in areas of major mountain systems (it is as much as 70 km thick in the Himalayan region).

MANTLE:

The portion of interior beyond the crust is called mantle. It extends from Moho’s discontinuity to a depth of 2,900 km.
The crust and the uppermost part of the mantle are called lithosphere. Its thickness ranges from 10-200 km.
The upper portion of the mantle (lower part of Lithosphere) is called Asthenosphere which is partially molten in condition whereby molten magma is in motion (it extends up to 400 km).
The lower mantle extends beyond the asthenosphere. It is in solid state.
Previously mantle was divided into two zones:
- Upper Mantle from Moho’s discontinuity to 1000 km depth
- Lower Mantle from 1000 to 2900 km depth.

On the basis of discovery by the International Union of Geodesy and Geophysics, the mantle is now divided into three zones.

Zone 1: Moho’s discontinuity to 200 km depth
Zone 2: 200 – 700 km depth
Zone 3: 700 – 2900 km depth

3. CORE:

The core-mantle boundary is located at the depth of 2,900 km.
The outer core is in liquid state while the inner core is in solid state.
Composition of Core: Core is made up of very heavy material mostly constituted by Nickel and Iron. It is sometimes referred to as the NiFe layer.

Significance of the Core:

Contains information regarding earliest history of accretion of planet
Earth's core plays a vital role in sustaining life on our planet and generates a magnetic field that shields us from the Sun's harmful radiation.
The inner core rotates independently of the liquid outer core and the rest of the planet, creating a dynamic motion that is essential for maintaining Earth's magnetic field.
Without dynamic motion, our planet would be unable to support life, and would likely become a barren, Mars-like landscape.

Findings of the New Study:

Research paper – “Annual Scale variability in both the rotation rate and near surface of Earth’s inner core”.
It is published in the scientific journal Nature Geoscience.
Highlights of the Study:
- The inner core of the Earth may have noticeably changed shape over the past few decades.
- Contrary to the long-held belief that the inner core is a perfect sphere, a team of scientists has proposed that its edges may have deformed by as much as 100 meters or more in certain areas. The change could have happened at the inner core’s outer boundary.
- Previous studies have found that the inner core spins slightly faster than the outer layers, scientists believe that the pace of rotation is slowing down.
- The researchers suggest that the liquid flow of the outer core, combined with the uneven gravitational field, may be causing the inner core to deform.

How was the study conducted?

Scientists study the behaviour of seismic waves to understand the earth's interior. They can infer the types of materials, density, and elasticity of rocks by analysing the speed and direction of seismic waves.
This time scientists have examined seismic wave patterns from earthquakes that occurred repeatedly in the same location (South sandwich island, Southern Atlantic Ocean) between 1991 and 2023.

By comparing these patterns over time, the researchers aimed to understand how the inner core has changed.

Significance of the research:

Findings are not that significant from the perspective of daily lives.
However, significance lies for the scientific community, so as to enable them to make more informed estimates of some important material properties, and to understand the earth’s interior and process therein.

Cauvery-South Vellar Linking Project

Context: The Central government is reluctant to approve the Cauvery-South Vellar link project stating various legal and environmental issues.

Relevance of the Topic: Prelims: Questions based on locations of rivers; key facts about Cauvery-South Vellar Link Project.

About Cauvery-South Vellar Link Project

Cauvery-South Vellar link project is a significant river-linking initiative proposed by Tamil Nadu government, as part of the first phase of Cauvery-Vaigai-Gundar linking scheme.
The project aims to transfer large quantities of water from Cauvery river to the South Vellar River, through a canal system.
Expected benefits of the project:
- Agriculture: Irrigation is the primary benefit of the project.
- Drought relief: help in mitigation of water scarcity in southern Tamil Nadu during dry seasons.
- Drinking water: Project will ensure supply of drinking water to urban regions of Tamil Nadu.

Challenges Leading to Delay

Inter-state dispute: Neighbouring states like Karnataka have objected to the project citing diversion of Cauvery river, one of the primary sources of water in Karnataka.
Environmental concerns: The project might fail to meet environmental and ecological standards. Linking projects can impact habitat and river ecology. E.g., Similar concerns delayed the Ken-Betwa river linking project.
Lack of comprehensive studies: The project lacks the prolonged study on long-term implication of the project, this became one of the reasons for the center to hold back the consent.
Potential of setting a precedent: Approving the project may lead to further demands of river-linking by other states too, that may lead to legal and environmental implications.
Economic viability: Financial burden of the project can elevate the cost of Cauvery-Vaigai-Gundar, degrading the economic viability of the complete project.

Suggested Measures to Address Challenges

Facilitating Inter-state dispute: The central government can play a pivotal role in mediating the consensus in Tamil Nadu and Karnataka to facilitate the completion of the project.
Conducting comprehensive EIA: A complete hydrological, environmental and socio-economic impact assessment needs to be conducted to mitigate the negative impacts on livelihood and habitat of the area.
Exploring alternative water management: Encourage Tamil Nadu to consider alternative methods like enhancing groundwater recharge, modernising irrigation infrastructure and implementing rainwater harvesting systems as a long-term solution to the water scarcity without causing inter-state disputes.

Facts about Rivers in the Project:

Cauvery: Originates through Talakaveri, Karnataka.
- States: Karnataka, Tamil Nadu, and Kerala
- Major conservations area: Nagarhole and Bandipur along its tributaries. Muthupet Mangroves and Pichavaram Mangroves (Tamil Nadu) near its delta region.
- Tributaries of Cauvery: Bhavani river (flows near Silent Valley Natural Park, Kerala); Amaravati river and Noyyal river.
South Vellar River: Originates from Sivaganga, Tamil Nadu
- States: Flows entirely within Tamil Nadu
- It is a non-perennial river dependent on monsoonal rains.
Vaigai river: Originates from Varusanadu Hills in Tamil Nadu.
- The major city near the shore is Madurai.
- Flows from Srivilliputhur Grizzled Squirrel Wildlife Sanctuary.
Gundar river: Originates from Western Ghats in Tamil Nadu.
- It is a seasonal river, often dry for significant portions of the year.

Z-Morh Tunnel

Context: The Prime Minister of India inaugurated the Z-Morh tunnel in Sonmarg area of the UT Jammu and Kashmir.

Relevance of the Topic: Prelims: Location based questions in Prelims.

About Z-Morh Tunnel

Z-Morh tunnel is situated between Gagangir and Sonamarg in Jammu & Kashmir.
The 6.5 km long tunnel provides a year-round alternative to the Zojila Pass (Zojila Pass connects Srinagar and Leh).
Purpose:
- Connectivity: The tunnel will facilitate tourism, trade, and military logistics in the region.
- Strategic importance: Together with the adjacent Zoji-La Tunnel, this geostrategically important tunnel on the Srinagar-Leh national highway provides year-round all-weather connectivity to Baltal (Amarnath cave), Kargil and other places in Ladakh.

About Zojila Tunnel Project

The Zojila Tunnel is a 13.14 km-long, all-weather tunnel connecting Srinagar and Leh, bypassing the Zojila Pass.
It ensures year-round connectivity, boosts tourism, enhances military logistics, and reduces travel time from 3 hours to 15 minutes.
It fosters regional development despite challenging high-altitude construction conditions and is expected to be completed by 2026.

What is the Polar Vortex?

Context: Large swathes of Canada and the USA were hit by a massive winter storm. At least five people have died in the United States over the weekend and the storm has led to mass school closures, dangerous road conditions and power cuts. The extreme weather has been caused by the expansion of the polar vortex southwards.

Relevance of the Topic:Prelims: Key facts about Polar Vortex.

What is Polar Vortex?

Polar vortex is a circulation of strong, upper-level winds that normally surround the Northern Pole, moving in a counter-clockwise direction, i.e., a polar low-pressure system.
These winds tend to keep the bitter cold air locked in Arctic regions of the Northern Hemisphere. On occasion, this vortex can become distorted and dip much farther South, allowing the cold air to spill Southwards.
There are two types of Polar Vortex: Tropospheric and Stratospheric:

Tropospheric polar vortex occurs at the lowest layer of the atmosphere — it extends from the surface up to about 10 km to 15 km — where most weather phenomena occur.
Stratospheric polar vortex occurs at around 15 km to 50 km high. Unlike the tropospheric polar vortex, the stratospheric polar vortex disappears during the summer and is the strongest during the autumn.

Formation of Polar Vortex:

Polar Vortex forms every winter because of the temperature difference between Equator and Poles.
In the polar stratosphere, sunlight basically gets cut off during the late fall and early winter—and that makes it cold, while the equator remains quite warm.
A jet forms to balance this temperature difference. This jet is what we call the Polar Vortex or Polar Night Jet.

Distortion of Polar Vortex:

When the pressure difference gets lower, the jet streams get weakened and follow a much wavier path. This change in intensity allows the dense Arctic cold wind to spill down to the lower latitudes and lead to major cold air outbreak in the US, parts of Europe, and Asia.
This oscillation is known as the Arctic Oscillation, and it can switch from a positive phase to negative phase a few times per year. This oscillation -- namely the Negative phase, where the polar winds are weaker, tends to lead to major cold air outbreaks in one or more regions of the planet.

Climate Change and Polar Vortex

Scientists are still researching the precise impact of climate change on the polar vortex. Some researchers believe that as the poles are getting warmer at a faster rate than the rest of the Earth, the polar vortex and jet stream are becoming weaker. Warmer temperatures make it easier for the polar vortex and jet stream to get disrupted.
This can be understood through following:
- Jet streams are propelled forward by temperature differences and the Earth's rotation. Warm air is less dense than cold air and rushes to fill in low-pressure regions. Wider temperature differences create faster moving winds.
- Earth is warming more quickly at the poles than at the mid-latitude regions, meaning the temperature contrast that drives jet streams has decreased.
- Complex sequence of events involving sea ice, which is rapidly diminishing in the Arctic. As ice retreats, summertime heat is absorbed by the dark ocean that lies underneath. This heat is released into the atmosphere during winter, spurring winds that can disrupt the polar vortex.

Global Water Monitor Report 2024

Context: According to the Global Water Monitor Report 2024, climate change has been wreaking havoc on Earth’s water cycle by disrupting how water circulates between the ground, oceans and atmosphere.

Relevance of the Topic: Prelims: Water Cycle; Global Water Monitor Report 2024.

Water Cycle

It involves the continuous circulation of water in the Earth-atmosphere system.
There are many processes involved in the water cycle, the most important are evaporation, transpiration, condensation, precipitation, and runoff.

Although the total amount of water within the cycle remains essentially constant, its distribution among the various processes is continually changing.
Most water cycles through the planet because of the energy from the Sun and changes in temperatures.
The water cycle is crucial as it not only enables the availability of water for all living organisms but also regulates weather patterns on the Earth.

Components and Processes of the Water Cycle

Components	Processes
Water storage in oceans	Evaporation, Evapotranspiration, Sublimation
Water in the atmosphere	Condensation, Precipitation
Water storage in ice and snow	Snowmelt runoff to streams
Surface runoff	Stream flow, freshwater storage, infiltration
Groundwater storage	Groundwater discharge springs

What is Climate Change?

Climate change refers to long-term shifts in weather patterns and average temperatures on Earth, primarily caused by human activities, such as the burning of fossil fuels, deforestation, and industrial processes.
Characterised by: Increase in greenhouse gas emissions, particularly carbon dioxide, which traps heat in the Earth's atmosphere and leads to global warming.
Impacts: Rising temperatures, changing precipitation patterns, melting glaciers and polar ice caps, sea-level rise, and altered ecosystems.
Consequences: Far-reaching consequences for human societies, ecosystems, agriculture, water resources, and natural disasters, posing significant challenges to global sustainability and the well-being of future generations.

Global Water Monitor Report 2024

Report: Global Water Monitor Report – 2024
Published by: Consortium of researchers from universities and organisations in countries like Australia, Saudi Arabia, China, Germany, Austria, USA, Netherlands and Denmark etc.

Key Global Findings

Climate change has intensified the water cycle by increasing the rate of evaporation, driven by rising air temperatures. This has resulted in increasing the strength, duration and rainfall intensity of monsoons, cyclones and other storm systems, causing severe flooding across the world.
Water-related disasters caused major damage in 2024. They caused over 8,700 deaths, displaced 40 million people, and inflicted more than US$550 billion in damages. Flash floods, landslides, and tropical cyclones were the worst types of disasters in terms of casualties and economic damage.
Both High rainfall and Drought are becoming more extreme. In 2024, months with record-low precipitation were 38% more common than during the baseline period of 1995-2005, while record-high 24h rainfall extremes were 52% more frequent.
Rainfall records are being broken with increasing regularity. For instance, record highs for monthly rainfall were set 27% more often in 2024 than in the year 2000, and daily rainfall records were set 52% more frequently.
Global temperatures continue to increase rapidly. Average air temperature over land area hit an all-time high, reaching 1.2°C above the 1995-2005 average. Over 111 countries experienced their warmest year yet, while 34 countries set new maximum temperature records.
Last year, most of the world’s dry regions experienced ongoing low values of the terrestrial water storage (TWS). However, the values increased in western, Central and Eastern Africa.
The outlook for 2025 shows increased risks. Seasonal climate forecasts and current catchment conditions signal potential worsening of droughts in northern South America, southern Africa, and parts of Asia. Wetter regions like the Sahel and Europe may face elevated flood risk.

Other Reports Cited

Nature journal – Study titled ‘Observed poleward freshwater transport since 1970’ (published in 2022) found that climate change had intensified the global water cycle by up to 7.4%.
The Intergovernmental Panel on Climate Change (IPCC) - In its sixth assessment report in 2021 said climate change will cause long-term changes to the water cycle. This would lead to more frequent and intense droughts and extreme rainfall events, the report added.

Read More: Impacts of Climate Change

Panama Canal

Context: The US President-elect Donald Trump criticised the current management of the Panama Canal, called the ‘Panama Treaty’ foolish and intended to regain the Panama Canal.

Relevance of the Topic: Prelims: Map based questions in Prelims on Straits and Canals.

About Panama Canal

Panama Canal is a man-made sea route that connects the Atlantic Ocean and the Pacific Ocean.
The approximately 80 km long canal is constructed across the Isthmus of Panama, Panama Country. It was constructed by the US and officially opened in 1914.
The canal is one of the major choke points of the world. It handles the 6% maritime trade volume of the world, and significantly reduces the cost, time and distance for international trade.

Transfer of Panama Canal to Panama:

The Panama Treaty, also known as the Torrijos-Carter Treaties, was signed between the US and Panama in 1977 to hand over the canal to Panama in a phased manner.
Transfer of Control: The Canal was turned over to Panama on December 31, 1999.

Active underwater hot spring in southern Indian Ocean

Context: Indian oceanographers have captured the image of an active hydrothermal vent located 4,500 metres below the surface of the Indian Ocean. This site holds potential for mineral exploration as part of the Rs 4,000-crore Deep Ocean Mission under the Ministry of Earth Sciences.

Relevance of the Topic: Prelims: Key facts about Hydrothermal vents.

What are Hydrothermal vents?

Hydrothermal vents (largely found near tectonic plates) are underwater springs where cold water (about 2 degrees Celsius) prevailing near the seabed comes in close contact with magma (molten rock formed in very hot conditions inside the earth) in a tectonically active region.
When this cold water trickles through cracks and fissures on the ocean crust and admixtures with magma, it gets heated up. It can turn into superhot water (up to 370 degrees Celsius) and later emerge as plumes, rich in minerals and gases, through chimneys and vents.

Key Facts:

Location: Hydrothermal vents in the deep ocean typically form along the mid-ocean ridges, such as the East Pacific Rise and the Mid-Atlantic Ridge. These are locations where two tectonic plates are diverging and a new crust is being formed.
Hydrothermal vents could remain active from a few hundred years to as long as 30,000 years.

Significance:

The discovery of hydrothermal vents in the Southern Indian Ocean is significant for exploration from both economic and biological perspectives.

Economic significance: The deposits from hydrothermal venting are generally rich in copper, zinc, gold, silver, platinum, iron, cobalt, nickel and other economically-beneficial minerals and metals. This discovery could significantly enhance India’s Deep Ocean mission focusing on mineral exploration from inactive vents.
Biological significance: The vents may contain living chemosynthetic organisms (underwater microbes rely on chemicals enriched with minerals and metals for their sustenance). The discovery could offer better insights into the organisms that inhabit environments supported by hydrothermal vents.

Arctic Tundra emits more Carbon than it Absorbs

Context: Recently, the US National Oceanic and Atmospheric Administration released the Arctic Report Card with interesting facts about the Arctic Tundra ecosystem.

Relevance of the topic: Prelims: Scope of question on reports, their findings and changes in ecosystem.

Major Highlights:

The Arctic tundra ecosystem holds 1.6 Trillion metric tonnes of carbon. This carbon is in the form of non-decomposed biomass that is frozen in permafrost.
In recent findings, scientists observed that the Arctic region is emitting more carbon than it absorbs.

Arctic Tundra emits more Carbon than it Absorbs

Reasons for this inverted trend

Global Warming: The rising temperature is leading to the thawing of the permafrost in the region. This is activating the decomposers and microbes.
- Due to microbial action the carbon dioxide and methane is synthesised from biological form to gaseous form leading to emissions.
Wildfires: Another major reason for rising emissions is the high frequency of wildfires in the year 2024.

Both these reasons contributed to a hike in emissions from the Arctic region.

Way Forward: The prime way forward suggested is to reduce carbon emission. This can be achieved by moving towards green technology like hydrogen fuel cells, and renewable energy sources.