Earth Sciences Flashcards
Why have there been Ice Ages?
There have been 5 major Ice Ages, ( Huronian, Cyrogenian, Andean- Saharan, Karoo, Pliocene-Pleistocene) in Earth’s history. Caused by a complex web of factors including the Sun’s energy output, Earths distance from the Sun and tectonic movement.
Who is Alfred Wegener?
Alfred Wegener (1880-1930) was a German astronomer, geologist, meteorologist, and Arctic explorer who proposed that Earth’s landmasses were all joined together. His theories were rejected because he could not explain how the continents moved.
Where is Krakatoa?
Krakatoa was a large volcano in Indonesia- although much smaller since 1883, when it blew itself to bits in of the largest explosions on record.
When was the Earth formed?
The Earth was from hydrogen, helium and heavier elements that came together in an interstellar cloud around 4.6 Billion years ago.
Why do animals migrate?
Migration is the seasonal movement of animals from one location to another. The principle reasons for this movement are to find suitable habitats in which to breed, more food for themselves or for their newborn young, and protection from extremes of weather, especially low temperatures. Migrations can take place over many thousands of miles as swallows and whales have amazing powers of navigation that ensure they end up in the right place.
Who found the source of the Nile?
in 1858, the British explorer John Hanning Speke discovered the vast lake that that he named Victoria. He claimed, correctly, that the white Nile flowed from this lake and that the lake us effectively the source. Several small rivers flow into Lake Victoria, and the source of the longest of these was located in 2006.
Where is the Great Barrier reef?
The Great Barrier Reef is a string of coral reefs and islands some 1200 miles (2,000 km) long. It lies of the northeast coast of Australia. The coral reef ecosystem supports an enormous diversity of marine life, but it is highly sensitive to environmental factors such as pollution and climate change.
What is the driest place on earth?
There are a great many very dry places on Earth, but the two most extreme examples are the Atacama Desert in Chile and the McMurdo Dry valleys in Antarctica.
When was the grand canyon formed?
The grand canyon was formed about 5 million years ago by the Colorado river cutting its way down through layers of rock that had been laid down over a period of about a billion years. The walls of the canyon provide a detailed history of the geology of this area.
When did the worse earthquake happen?
The most powerful recorded earthquake took place in Chile in 1960. The magnitude 9.5 quake struck relatively sparsely populated area, and the total death toll was but 6000 people. The earthquake with the highest death toll struck central china in 1556. A large proportion of the 830,000 people killed by the Shaanxi or Jiajing earthquake were dwelling in caves that collapsed.
Why is tourism so important?
Tourism is important because it forms the backbone of many developing economies, and it provides major source of revenue and employment in developed countries. By exposing travelers to other lands, peoples, and cultures, tourism at its best encourages a broader world view and promotes understanding. At its worst it can be destructive and exploitative.
Who was Gerardus Mercator?
Gerardus Mercator was a 16th century mapmaker. His ground-breaking projection solved some of the problems of plotting our three dimensional planet in two dimensions. Mercator’s projection is well-suited for navigation; however, it does distort size, meaning that the view of the world we hold in our heads is not an entirely accurate one.
Where is the world’s largest city?
Taking “city” to mean a municipal administrative unit, the world’s most populous city is Mumbai India with about 14 million. It also has one of the highest population densities in the world. If one takes “city” to mean metropolitan area as a whole, Tokyo has the greatest population (33 million)
What is climate change?
Climate change is a global process tat includes warming of the lands, seas, and atmosphere, as well as changes to the world’s weather patterns, melting of ice caps and glaciers, rising sea levels, and an increase in extreme weather events. It is probably largely due to an increased concentration of carbon dioxide (CO2) in the atmosphere as a result of the burning of fossil fuels.
