Category Science

HOW OLD IS GLACIER ICE?

  • The age of the oldest glacier ice in Antarctica may approach 1,000,000 years old
  • The age of the oldest glacier ice in Greenland is more than 100,000 years old
  • The age of the oldest Alaskan glacier ice ever recovered (from a basin between Mt. Bona and Mt. Churchill) is about 30,000 years old.

Glacier flow moves newly formed ice through the entire length of a typical Alaskan valley glacier in 100 years or less. Based on flow rates, it takes less than 400 years for ice to transit the entire 140 + mile length of Bering Glacier, Alaska’s largest and longest glacier.

Picture credit: Google

HOW MUCH OF THE WORLD IS COVERED BY ICE?

Almost 10 per cent of Earth’s total landmass is covered by ice. This includes glaciers, Ice caps and ice sheets. Glaciers cover 15 million km2. During the last ice age, 32 per cent of the total land area was covered by ice.

Most of the Earth’s ice that we see is to be found in large masses of “nearly” pure ice: ice-sheets and glaciers of various types, ice shelves and sea ice packs. It is quite easy to calculate the surface of the areas covered with ice: it has been calculated that this amounts to approximately 15 million km2, equal to one tenth of the surface of the Earth’s emersed land. It is more difficult, on the contrary, to calculate the volume of ice because the thickness of the entire covered area must be known: using special techniques it is possible to measure the ice thickness in various points of a glacier and therefore to estimate the volume. For example the average thickness of the Antarctic sheet is 2,100 m, with peaks of 4,800 m in Land of Wilkes, in the Eastern sector: with a surface of little less than 13,600,000 km2, the total volume of the Antarctic ice is 30 million km3.

Credit: Energy & environment

Picture credit: Google

 

DOES ANTARCTICA HOLD MOST OF THE WORLD’S FRESH WATER?

The Antarctic ice cap contains about 91% of all the ice in the world and about 86% of all freshwater that occurs in the form of ice. But despite all this freshwater, Antarctica is considered one of the most arid places on Earth.

Antarctica is the highest, coldest, driest, and windiest of the world’s continents. It is also “tallest” in terms of average height above sea level. Nearly 99% of this land mass is covered with an ice cap with an average altitude of around 2 200 metres above sea level. The area of this vast continent – some 14 million square kilometres – doubles in the winter, when sea ice can stretch as much as 1000 km outwards from the coastline.

Most of the continent of Antarctica lies south of 70°S, although the Antarctic Peninsula stretches northward as far as 60°S. The continent is surrounded by the Southern Ocean, a circumpolar sea that isolates Antarctica from the other continents.

Most of Antarctica is covered with ice, but in many places mountain peaks (nunataks) stick up out of the ice. The Vinson Massif in West Antarctica, with an elevation of 5 140 m, is the highest peak in Antarctica. In addition to the nunataks, there are large ice-free regions called oases where the ice has retreated and where melting outstrips accumulation of new snow. Other areas, known as dry valleys, are free of ice because essentially no precipitation falls there.

Picture credit: Google

Elusive hummingbird species spotted in Colombia

An elusive and rare hummingbird has been rediscovered in Colombia by a birdwatcher. The hummingbird Santa Marta sabrewing has been spotted years after it was first recorded in 2010. The news has sent ornithologists across the world into a state of excitement as they celebrate the find.

This is the third time that the species has been documented. It was first documented in 1946 and later in 2010 when the researchers captured pictures of the species in the wilderness.

The bird was spotted by Yurgen Vega during a survey of the endemic birds in the Sierra Nevada de Santa Marta. The researcher said that the sighting was a complete surprise and that he was overwhelmed with emotion when he first spotted the bird.

The hummingbird Santa Marta sabrewing, which is only found in the Sierra Nevada de Santa Marta mountains of Colombia was thought to have gone extinct by many ornithologists. This species of hummingbird has been listed on the IUCN red list of threatened species ‘as critically endangered’. The bird also figures in the Top 10 ‘most wanted’ list of the ‘Search for Lost Birds’ initiative of conservation organisations.

The hummingbird spotted by Yurgen Vega was male. The bird is identified by its emerald green feathers, bright blue throat and curved black bill The bird was spotted to be singing and vocalising. Scientists associate this behaviour to either courtship or defending territory.

John Mittermeier, director of threatened species outreach at the American Bird Conservancy has likened the rediscovery to “seeing a phantom”.

The species is believed to live at an altitude of 1200 to 1800 metres in the neotropical forest. During the rainy season, they are known to migrate in search of flowering plants.

The Sierra Nevada de Santa Marta in northern Colombia is rich with wildlife and home to 24 bird species that aren’t found anywhere else. Yet, according to scientists, only 15 per cent of the habitat is intact. The spotting of the hummingbird has further intensified the call to protect these forests which can solely aid in the conservation of the rare species dwelling there.

Armed with this information, the scientists will now focus on identifying stable populations of this species which can help them come up with conservation strategies and learn more about the bird.

What’s the IUCN Red List?

The International Union for Conservation of Nature’s Red List of Threatened Species is an indicator of the health of the biodiversity in the world. The global conservation status of animals, plant species and fungi are covered under this. The list indicates the conservation status of the species and helps in formulating conservation plans. It gives information such as the habitat, population size, ecology, threats the species faces and so on. At present, there are more than 147,500 species on the IUCN Red List of which more than 41.000 species figure under the “threatened with extinction” category.

What’s ‘Search for Lost Birds’

A joint initiative of conservation organistaions Rewild’, ‘American Bird Conservancy (ABC) and ‘Bird Life International’, the Search for Lost Birds’ attempts to find 10 species that haven’t been observed in the wild for over a decade but do not figure in the extinct category of IUCN Red List of Threatened Species.

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Can reforestation alone save the Earth?

Trees are huge carbon sinks. They saok up the carbon. Planting trees will help mitigate the climate change and cool the planet to some extent. But that has to be combined with a dedicated effort to reduce carbon emission. Reforestation combined with the reduction of greenhouse gases, especially carbon dioxide (CO2), is the need of the hour. It is these gases that warm the earth, leading to climate change which we have been witnessing in many forms such as the melting of ice sheets, rising of sea levels, wildfires, floods, droughts and other natural calamities. So the carbon emissions need to be reduced by nations, on an industrial scale as well as individual level.

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1000 trees are presently ‘walking’ down the streets of the Dutch city of Leeuwarden

1000 trees are presently walking down the streets of the city of Leeuwarden, Netherlands. Or rather, the indigenous trees planted in big wooden containers are being lugged around by volunteers. The idea is to let people experience a greener and cleaner alternative.

The unique initiative has been launched as part of the art project ‘Bosk, envisaged by architect Bruno Doedens and his collaborator, the late Joop Mulder.

The trees will keep moving around the city till August 14, after which they will be planted across the city. The idea emerged from Doedens 2021 essay Planet Paradise. The essay questions the relationship of humans with the natural world.

Bosk means forest in the local Frisian language. The move is an attempt to raise awareness about climate change. The trees are being moved by thousands of volunteers and roads are closed when the trees are walking. The trees rest on the weekend.

It all started in the month of May, when volunteers started moving the trees in huge wooden containers. After starting their journey, the trees first stopped at Stationsplein. outside Leeuwarden’s train station.

Whilst the trees aren’t moving, seating areas are provided between the trees to let the people experience life when there is more green cover. Around 60-70 varieties of native trees such as maple, oak, elm, willow, alder, and ash are planted in the wooden containers.

QR codes have been given which lets one know the details such as the species name, its lifespan, soil type, and so on. The city gardening team gets an alert whenever water is required by the tree. A soil sensor alert has been provided for this.

 The trees will get their permanent home in the city after 100 days. The trees will trundle down these roads until August 14 and will later be planted across the city where the greenery is limited.

Picture Credit : Google