Current Affair 1:

Loss of Mangrove Forests Worldwide Is Slowing – Except in Asia

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In their Global Forest Resources Assessment (FRA) for 2020, the Food and Agriculture Organization of the United Nations (FAO) estimated the loss of 1.04 million hectares (2.57 million acres) over the last 30 years. However, there is some cause for some optimism. According to figures from the FRA, the rate of global mangrove loss has more than halved over three decades, from 46,700 ha (115,400 acres) of loss per year between 1990 and 2000, to 21,200 ha (52,400 acres) per year between 2010 and 2020.

However, not all regions have experienced a reduction in mangrove deforestation. The FRA found that in Asia, there has been a huge increase in mangrove loss: from 1,030 ha (2,550 acres) per year to 38,200 ha (94,400 acres) over the same 30-year period.

First of all, we should know, why protecting Mangroves is important?

They are a natural coastal defence

The sturdy root systems of mangrove trees help form a natural barrier against violent storm surges and floods. River and land sediment is trapped by the roots, which protects coastline areas and slows erosion. This filtering process also prevents harmful sediment reaching coral reefs and seagrass meadows.

They are carbon sinks

Coastal forests help the fight against global warming by removing carbon dioxide from the atmosphere, most of which is stored within the plant. When mangrove tree roots, branches and leaves die they are usually covered by soil, which is then submerged under tidal water, slowing the breakdown of materials and boosting carbon storage.

They provide livelihoods

Many people living in and around mangroves depend on them for their livelihood. The trees are a reliable source of wood for construction and fuel, which is prized for its hardy resistance to both rot and insects. However, in some areas, the wood has been harvested commercially for pulp, wood chip and charcoal, raising concerns about sustainability.

Plant extracts are collected by locals for their medicinal qualities and the leaves of mangrove trees are often used for animal fodder. The forest waters provide local fishermen with a rich supply of fish, crabs and shellfish to sell for income.

They encourage ecotourism

Sustainable tourism offers a stimulus to preserve existing mangrove areas, with potential to generate income for local inhabitants. Often located near to coral reefs and sandy beaches, the forests provide a rich environment for activities like sports fishing, kayaking and birdwatching tours.

They are rich in biodiversity

Human activity has caused huge biodiversity loss in land and marine ecosystems around the globe, endangering many plant and animal species. By filtering coastal waters, mangroves form a nutrient-rich breeding ground for numerous species that thrive above and below the waterline.

Now,

What India Forest Report 2020 says about status of Mangroves in India?

1. The current assessment shows that mangrove cover in the country is 4,975 sq km, which is 0.15% of the country’s total geographical area.
2. Very Dense mangrove comprises 1476 sq km (29.66%) of the mangrove cover, Moderately Dense mangrove is 1479 sq km (29.73%) while Open mangroves constitute an area of 2020 sq km (40.61%).
3. There has been a net increase of 54 sq km in the mangrove cover of the country as compared to 2017 assessment.

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Current Affair 2:

Jupiter’s icy moon Europa

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Jupiter’s icy moon Europa, which is set to be the next favourite exploration destination due to the presence of an under-ice ocean, may actually glow in the dark, NASA scientists have discovered. The findings are predictions made from Earth-bound experiments at NASA’s Jet Propulsion Laboratory (JPL) in California, which recreated Europa and Jupiter’s interactions.

The team found that the moon possibly glows blue-white and blue green through its ice and water interior, even at night, because of the radiation from its host planet Jupiter.

Although the glow has not been directly observed by telescopes yet, using a spectrometer to observe and identify different signatures in the composition of ice during Europa’s night can give insights into the evolution of Jupiter and its moons.

1. Jupiter emits the strongest radiation after the sun and is surrounded by the biggest planetary magnetic field in the solar system, which accelerates charged particles to high energies. This enormous magnetosphere spans over 1 million km in radius, engulfing Europa and many other moons.
2. Europa is one of the more promising candidates when it comes to potential habitability. The moon is covered with a solid crust made of water ice and is thought to hold liquid water underneath. Water is one of the strongest biomarkers or indicators of potential habitability.
3. To understand the effect of Jupiter’s charged high-energy activity on its icy moon’s contents, scientists had to add minerals present on the moon’s surface to the ice-water mix.
4. These included a variety of salts including common salt. It is commonly known that high energy particles energies molecules, which then release energy in the form of light by producing a glow.
5. The team discovered that whenever they beamed through the water, it glowed and the glow stopped when the beam was stopped.

Future projects:

Europa is fast becoming the next big destination in planetary research thanks to findings from the ongoing Juno mission around Jupiter. Multiple missions to the icy moon are currently under consideration.

The JUpiter ICy moons Explorer (JUICE) is an interplanetary spacecraft in development by the European Space Agency (ESA). It will orbit the largest Jovian moon Ganymede and will also study Callisto and Europa in detail. It is scheduled to launch in 2022.

NASA’s Europa Clipper is the next and first mission dedicated to Europa. It comprises an orbiter that will fly around Jupiter but will make a series of close flybys to study the moon. The mission is set to launch in 2024.

Current Affair 3:

New UN alliance to curb food crisis

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The novel coronavirus disease (COVID-19) pandemic has pulled food systems apart, threatening food security and nutrition. At least 690 million people went hungry in 2019, according to the State of Food Security and Nutrition in the World report, 2020. Now, the pandemic could tip over 130 million more people into chronic hunger by the end of 2020, according to the report.

Taking cognizance of the catastrophic food crisis and the urgency to tackle it, Food and Agriculture Organization (FAO) of the United Nations launched a Food Coalition on November 5, 2020.

Proposed by Italy and led by FAO, the global alliance aims to help countries get back on track to achieve the UN-mandated Sustainable Development Goals by 2030, especially the ones on ending hunger and poverty. More than 30 countries have already expressed interest in joining the coalition.

Current Affair 4:

Ancient skeleton offers clues on prehistoric era

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German researchers are piecing together the life of a prehistoric woman who died more than 5,000 years ago in the Neolithic period, after her skeleton was found when excavating for wind turbines.

She has been named, the “Lady of Bietikow”.

Investigations have shown that she was between 30 and 45 years old and died more than 5,000 years ago. All that is left of the skeleton are bones and some fragments of clothing.

Prehistoric Age refers to the time where there was no writing and development. It consists of five period, divided according to the tools used by people then –

1. Paleolithic Period: 2 million BC – 10,000 BC
2. Mesolithic Period: 10,000 BC – 8000 BC
3. Neolithic Period: 8000 BC – 4000 BC
4. Chalcolithic Period: 4000 BC – 1500 BC
5. Iron Age: 1500 BC – 200 BC

Neolithic Period (New Stone Age)

1. Starting of agriculture
2. Moving from nomadic to settled life
3. Wheel discovered. Ragi, wheat and horse gram were cultivated
4. They knew to make fire
5. Knew pottery

Important sites:

One of the most important Neolithic agricultural settlements in Indian subcontinent is Mehrgarh. It is now considered oldest agricultural settlement in the Indian subcontinent. It flourished in the seventh millennium B.C. It is located on the Bolan River, a tributary of the Indus, at the eastern edge of the Baluchistan plateau.

Other important Neolithic sites include –

1. Gufkral and Burzahom in Kashmir
2. The people in Burzahom lived in pit dwellings, rather than building houses on the ground.
3. Mahgara, ChopaniMando, and Koldihwa in Belan valley in Uttar Pradesh
4. Belan valley sites have provided oldest evidence of rice cultivation in any part of the world
5. Chirand in Bihar
6. In South India, the important Neolithic sites include Kodekal, Utnur, Nagatjunikonda, Palavoy in Andhra Pradesh; Tekkalkolta, Maski, Narsipur, Sangankallu, Hallur, and Brahmagiri in Karnataka; Pariamlpalli in Tamil Nadu etc.

Current Affair 5:

Glacial lake outburst

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A glacial lake outburst flood (GLOF) is a release of melt water from a moraine- or ice-dam glacial lake due to dam failure. GLOFs often result in catastrophic flooding downstream, with major geomorphic and socioeconomic impacts.

GLOFs have three main features:

1. They involve sudden (and sometimes cyclic) releases of water.
2. They tend to be rapid events, lasting hours to days.
3. They result in large downstream river discharges (which often increase by an order of magnitude).

The general global trend of glacier shrinkage has seen the number and size of glacial lakes increase at the same time as human activities have expanded further into glaciated catchments. The study of how GLOFs occur and their impacts is therefore important for future hazard mitigation.

Recent study

Using remote sensing data, researchers from Germany have mapped the evolution of 2014 Gya glacial lake (Ladakh) and cause of the flood.

Finding of the study

1. The cause of the flood — was not a spill over but rather a tunneling drainage process. For Example - Imagine a bucket full of water. It can overflow when you drop a stone, or the water can drain if there is a hole under the bucket.
2. Similarly, here the flooding did not happen due to the spill over due to an avalanche or landslide, rather there was a thawing of the ice cores in the moraine [a field of dirt and rocks that have been pushed along by the glacier as it moves] which drained through the subsurface tunnels.
3. Such thawing of ice cores may accelerate in the future due to global climate change. warning.
4. It is almost certain that other glacial lake outburst floods will happen all over the Indian Himalaya. However, not all of these events have catastrophic outcomes. It largely depends on urban planning, the size of the lake, the distance between the lake and affected villages, the valley section and some more aspects. In some cases, cloudbursts can also trigger glacial lake outburst flood events like in Kedarnath in 2013.
5. In different sections of the Himalaya the occurrence of such floods has received different attention. While these events have been regarded as a major risk in the central Himalayan region including Sikkim, the arid Trans-Himalayan regions of Ladakh have received attention only recently.
6. Here the glaciers are located at high altitudes and most glaciers are of small size. Likewise, the glacial lakes are quite small in size. In the case of the Gya lake the lake is almost always ice-covered, even during summer –still event of glacial lake outburst was seen to occur.

Solution

1. To take more bathymetric studies to analyze lake volumes.
2. To undertake regularly monitoring of lake development.
3. Study to understand stability of the moraines that dam the lake.
4. Use multiple methods for better risk assessment and early warning.
5. Need of proper land use planning.

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