Category Geography

IN A YEAR HOW MANY CLOUD-FREE NIGHTS DOES THE ATACAMA DESERT GET?

At 16,570 feet (5,050 meters) in elevation, the Atacama Desert plateau may be the best place in the world to spot the solar system’s secrets. To the delight of amateur astronomers, the desert sees as many as 330 cloud-free nights each year. High along the Atacama Desert plateau, an array of observatories track the celestial bodies in our solar system and beyond.

The Atacama Large Millimeter Array/submillimeter (ALMA) — a network of 66 telescopes run by an international collaboration of scientific organizations from Europe, North America, East Asia and the Republic of Chile — spies on faraway stars and the planets birthed around them.

The European Space Observatory’s Very Large Telescope, helped spot the TRAPPIST-1 system of Earth-like planets, located a mere 40 light-years from Earth, and has gathered data on distant exoplanet atmospheres. This telescope, along with others, has uncovered some of the universe’s most intriguing oddities and provided a wealth of data to researchers and astronomers worldwide.

Credit: LIVE SCIENCE

Picture Credit: Google

WHAT IS AN ERG?

A large area full of sand dunes in a sandy desert is called an erg. As they are formed by the wind, it is likely that their shape, or their number, may change over a period of time. A large erg can spread over many kilometres.

An erg is a broad, flat area of desert covered with wind-swept sand with little or no vegetative cover. The word is derived from the Arabic word arq (???), meaning “dune field”. Strictly speaking, an erg is defined as a desert area that contains more than 125 km2 (48 sq mi) of aeolian or wind-blown sand and where sand covers more than 20% of the surface. Smaller areas are known as “dune fields”. The largest hot desert in the world, the Sahara, covers 9 million square kilometres (3.5×106 sq mi) and contains several ergs, such as the Chech Erg and the Issaouane Erg in Algeria. Approximately 85% of all the Earth’s mobile sand is found in ergs that are greater than 32,000 km2 (12,355 sq mi). Ergs are also found on other celestial bodies, such as Venus, Mars, and Saturn’s moon Titan.

Credit: Wikipedia

Picture credit: Google

HOW OLD IS THE KALAHARI DESERT?

The Kalahari Desert is not really a desert, but rather a large arid to semi-arid sandy area in southern Africa, covering much of Botswana and parts of Namibia and South Africa. Though it is semi-desert, it has huge tracts of excellent grazing after good rains and is rich in wildlife.

The Kalahari has existed as an inland desert since the Cretaceous period (65-135 million years ago). It has experienced both periods of greater humidity and more aridity, documented in fossil dune fields. It was during a period of greater rainfall that the Makgadikgadi Depression in northern Botswana was formed. The former lake at one point covered 23,000 square miles (60,000 square kilometers), about the same size as Lake Victoria today. The dry riverbeds that now only hold water when it rains are also from such periods.

Credit: New World Encyclopedia

Picture Credit: Google

IN WHICH DESERT WERE DINOSAUR EGGS DISCOVERED?

The Gobi Desert straddles Mongolia’s southern border with China’s autonomous region of Inner Mongolia. It is a cold desert formed in the rain shadow of the Himalayas. The world’s highest mountain chain blocks clouds from the Indian Ocean from making it over the Tibetan Plateau and into the Gobi area.

During the late Cretaceous, some 70-80 million years ago, the Gobi region was a lot different. Parts of it were covered by dense conifer forests, criss-crossed by streams and dotted with lakes. Today, though, thanks to the desert’s barren, rock-strewn landscapes, paleontologists have found so many incredible fossils. The rocks from the lush dinosaur age are already exposed at the surface and ready to be explored.

The first-ever positively identified dinosaur eggs became one of the first sensational finds from a rocky outcrop called the Flaming Cliffs. Andrews thought the eggs belonged to a dinosaur called Protoceratops, a small hornless relative of Triceratops. Intriguingly, in other finds, a feathered carnivorous dinosaur called Oviraptor had also been found fossilized on top of Protoceratops eggs. In the 1990s scientists discovered that the eggs actually belonged to Oviraptor and these fossils were the first known evidence of dinosaur brooding behavior, a further evolutionary link with birds. Sadly, because of scientific naming rules, Oviraptor will always bear the Latin name “egg plunderer”.

Credit: EARTH ARCHIVES

Picture credit: Google

What are the most wonderful waterfalls in the world ?

Waterfalls are nature’s magnificent creations. Nothing warms the cockles of your heart as watching the waters surging and leaping across mountains. From the world’s highest uninterrupted waterfall to the chocolate-coloured waterfall, we bring you the most dazzling sights from across the world.

GRAND FALLS- ARIZONA

Grand falls is a waterfall right in the midst of a desert. The Grand Falls in Arizona are taller than the Niagra Falls. The water falling in many tiers across the cliff is a delight to watch. Its muddy cascade has earned it the name Chocolate Falls.

NIAGARA FALLS- USA/CANADA

Surging forth with a thunderous force, these falls make for a resplendent sight. The name means ‘thunder of waters’, denoting the loud, roaring sound the waters make as they dive A part of the falls is located in Canada, while another is located in the United States. The former is called the ‘Horseshoe Falls’ courtesy of its curved shape and the latter ‘American Falls’.

ANGEL FALLS- VENEZUELA

Dropping from a height of 3,212 feet, the Angel Falls in Venezuela is the highest waterfall in the world. Pouring out from a flat-topped plateau Auyantepui, the falls are located in Canaima National Park. The falls are about 16 times the height of Niagara Falls. Set against the dense jungle and the green surrounds, the waterfalls are one of the major attractions in Venezuela. Angel Falls is named after Jimmy Angel, an American bush pilot, who crash-landed his four-seater airplane at the Auyantepui.

NOHKALIKAI FALLS, MEGHALAYA, INDIA

Plummeting from a height of 340 m. the Nohkalikai Falls is India’s tallest plunge waterfall. Located at Cherrapunji in Meghalaya, India, the waterfall is all about drama and grandeur. There is also a tragic legend that backs the name of the falls. The waterfalls are apparently named after Likai, a Khasi woman. When translated from the local Khasi language. Nohkalikai means Jump of Ka Likai’.

VICTORIA FALLS – ZIMBABWE

This curtain of waterfalls dropping from a height of 108m into the gorge below makes one of Earth’s greatest spectacles. Explorer David Livingstone named the falls after the reigning British monarch Victoria. The local name of the waterfall is ‘Mosi-oa-Tunya’ meaning ‘smoke that thunders. It is called so because the sound of the falls can be heard from a long distance.

Picture Credit : Google 

WHAT IS A MUSHROOM ROCK?

A rock that is shaped like a mushroom! What’s interesting is how the rock gets that shape. The strong winds blowing across desert landscapes erode the base of massive boulders more than the top. Over many years, this results in a thin stem supporting a broad cap – a mushroom rock.

Mushroom rock is a naturally occurring rock with the shape of a mushroom. The rocks are deformed in a variety of ways due erosion and weathering, glacial action, and sudden disturbances. Mushroom rocks are generally formed due to such deformations. We will learn about mushroom rocks associated with wind Erosional Landforms/ Aeolian Landforms.

  • Mushroom Rock, also known as a perched rock or pedestal rock, is a boulder balanced on a pinnacle rock or over another boulder or in some other position.
  • Rainwash generally removes the fine debris from around the boulder, causing some elevated rocks to develop.
  • Mushroom rocks are usually found with a strong capping and crumbling or exudation along their edges.
  • these types of rocks are generally found in deserts.

Formation of Mushroom Rocks

  • In mushroom rocks, the wind-carried sand rarely rises more than three or four feet above the ground, although the concentration of the sand is highest at eighteen inches closest to the ground.
  • As a result, the sandblast or abrasion effect will be greatest at or near the ground level.
  • The upstanding rocks at their bottoms are undercut by continued abrasive action, resulting in Rock pedestal or Mushroom rocks.

Picture credit: Google