Basics Of Geography Flashcards
What is the technical term for the longest day in the Northern Hemisphere (around June 21st)?
Summer Solstice.
What is the tilt of Earth’s axis relative to the sun?
23.5 degrees.
How does day length on the Summer Solstice vary with latitude?
The effect is greatest farther from the equator; 12 hours at the equator, slightly longer in tropics, significantly longer in temperate zones, 24 hours (Midnight Sun) within the Arctic Circle.
What force causes the deflection of wind direction due to Earth’s rotation?
The Coriolis force.
In which direction does the Coriolis force deflect winds in the Northern and Southern Hemispheres?
To the right in the Northern Hemisphere, and to the left in the Southern Hemisphere.
How does the Coriolis force vary with latitude?
It is directly proportional to the angle of latitude, being maximum at the poles and absent at the equator.
Why are soils in tropical rainforests generally nutrient-poor?
Nutrients from rapid decomposition are quickly consumed by fast-growing plants, and leftover nutrients are leached away by abundant rainfall.
What factors contribute to the rapid decomposition of organic matter in tropical rainforests?
High temperatures enhance microbial activity, and high moisture levels facilitate the enzymatic processes involved in decomposition.
During which season is the temperature contrast between continents and oceans greater?
During winter.
How does the specific heat of water compare to that of land?
Water’s specific heat is about 2.5 times higher, meaning it takes longer to heat up and cool down compared to land.
Approximately how much more insolation (solar radiation) does the equator receive compared to the poles?
About 4 times as much.
What percentage of insolation do infrared rays constitute?
Roughly 49-50%.
Are infrared waves visible to the human eye?
No, their wavelengths are longer than those of visible light.
When does the Southern Hemisphere experience its longest day (Summer Solstice)?
Around December 22nd.
What is the largest reservoir of freshwater on Earth?
Glaciers and ice caps, holding about 69% of total freshwater.
After glaciers and ice caps, where is the next largest proportion of freshwater found?
As groundwater, holding about 30% of total freshwater.
Along which latitude does the sun appear directly overhead during the June Solstice?
The Tropic of Cancer (approximately 23.5° N latitude).
What is Earth’s magnetosphere and what is its function?
It is the immense magnetic field surrounding Earth, shielding the planet from erosion of the atmosphere by solar wind, harmful particle radiation from CMEs, and cosmic rays.
Is Earth’s magnetic field constant?
No, it is in continual flux, with its strength changing, and the magnetic poles gradually shifting and even flipping polarity over long periods (e.g., every 300,000 years or so).
What was Earth’s early atmosphere primarily composed of?
Gases from volcanoes, such as ammonia, methane, hydrogen sulfide, and carbon dioxide; it lacked free oxygen.
What organisms were responsible for introducing significant amounts of free oxygen into the atmosphere?
Photosynthetic microbes called cyanobacteria, which became abundant around 2.4 billion years ago.
How can reduced or zero tillage practices help in water conservation in agriculture?
By reducing soil compaction, water runoff, and evaporation, preventing soil erosion, and allowing better utilization of residual moisture, thus potentially reducing irrigation needs.
What effect does applying gypsum have on certain types of soil?
It improves drainage and water infiltration, especially in soils with high sodium or swelling clay content.
What causes the change of seasons on Earth?
The change in the position of the Earth around the Sun due to its revolution on a tilted axis.
What causes the variations in the length of daytime and nighttime throughout the year?
The revolution of the Earth on its tilted axis.
What occurs in the Northern Hemisphere around June 21st (Summer Solstice)?
It is tilted towards the sun, receives more direct sunlight (especially at the Tropic of Cancer), experiences its longest day and shortest night, and areas north of the Arctic Circle have continuous daylight.
What occurs in the Southern Hemisphere around December 22nd (its Summer Solstice / Winter Solstice in N. Hemi)?
It is tilted towards the sun, receives more direct sunlight (at the Tropic of Capricorn), and experiences summer with longer days and shorter nights.
What is an equinox, and when does it occur?
A time when the sun’s direct rays fall on the equator, neither pole is tilted towards the sun, and the whole Earth experiences equal days and equal nights. Occurs around March 21st and September 23rd.
How was the Pole Star (North Star) used in ancient times?
For navigation at night, as it indicates the direction North and remains in the same position in the sky.
What is the difference in composition between asteroids and comets?
Asteroids are rocky minor planets, while comets are composed of ice, dust, and rock, often considered leftovers from solar system formation.
Where are most asteroids found?
In the asteroid belt, located between the orbits of Mars and Jupiter.
Where are comets typically found?
Orbiting the Sun in the distant Kuiper Belt and Oort Cloud.
Why do comets develop tails when they approach the Sun?
The Sun’s heat vaporizes the ice, and solar radiation pressure and solar wind blow the released dust and gas away from the nucleus, forming a tail.
Where is the ionosphere located?
Between approximately 80 km and 400 km above the Earth’s surface.
Why is the ionosphere important for radio communication?
This electrically charged layer (due to ionized atoms) can reflect radio waves, enabling long-distance communication. (Note: Reflection depends on frequency.)
Where is the ozone layer located?
Within the stratosphere, below the ionosphere.
What percentage of Earth’s surface is covered by water, earning it the nickname ‘Blue Planet’?
Around 71%.
What does ‘freshwater’ refer to?
Water other than seawater or brackish water, having considerably low amounts of dissolved salts. Includes ice caps, glaciers, groundwater, lakes, rivers, etc.
What is Earth’s albedo?
A measure of its reflectivity – how much incoming sunlight is reflected back into space.
What are the primary factors determining Earth’s global albedo?
Cloud cover and ice cover on land (especially large ice caps like Greenland and Antarctica).
What is Earth’s core primarily made of?
Nickel (Ni) and Iron (Fe), often referred to as ‘nife’.
Which major European river flows through six countries including Germany and France before emptying into the North Sea at Rotterdam?
The Rhine River.
Which river flows through London?
The River Thames.
Which four national capitals does the Danube River flow through?
Vienna (Austria), Bratislava (Slovakia), Budapest (Hungary), and Belgrade (Serbia).
What are the ‘horse latitudes’?
Subtropical atmospheric high-pressure belts located around 30°-35° North and South latitudes, characterized by light winds and clear skies.
Which is longer, a terrestrial mile or a nautical mile?
A nautical mile (approx. 1.85 km) is longer than a terrestrial mile (approx. 1.6 km).
What is the Harmattan?
A dusty, cool, dry wind blowing from the northeast/east in the western Sahara over West Africa, strongest in late fall and winter.
Which countries primarily make up the Iberian Peninsula?
Portugal and Spain.
Why does air temperature generally decrease with increasing altitude in the troposphere?
The Earth’s surface is heated by the sun, which warms the air near it. This warm air rises, expands, and cools as it moves further from the heat source.
Why is the troposphere thickest at the equator?
Because intense solar heating at the equator causes strong convectional currents that transport heat to greater heights compared to the poles.
Which type of forest covers the highest percentage of forest area in the world?
Temperate Coniferous forests.
What type of climate characterizes Temperate Coniferous forests?
Temperate regions with warm summers, cool winters, and adequate rainfall to sustain a forest.
In which latitudinal belt does convectional rainfall commonly occur throughout the year?
Areas lying within 5° to 8° latitude on either side of the equator.
Why does this region experience frequent convectional rainfall?
Due to consistently high humidity and high temperatures.
Which planet in our solar system is the densest?
Earth, with an average density of 5.52 g/cm³.
What is the predominant chemical element in Earth’s overall composition (by mass)?
Iron (approximately 35%).
What is the predominant chemical element in Earth’s crust?
Oxygen (approximately 46%).
Approximately what percentage of the total mass of the solar system does the Sun contain?
More than 99%.
Why do volcanic eruptions generally not occur in the Baltic Sea?
Because it does not lie between tectonic plates.
How did the Baltic Sea primarily form?
From the meltwaters of the retreating ice sheet around 13,000-14,000 years ago, influenced by land uplift due to de-glaciation.
Which scholar proposed the “Interstellar dust hypothesis” regarding Earth’s origin?
O. Schmidt.
According to this hypothesis, how did the solar system form?
From a cloud of gas (mostly hydrogen and helium) and dust that slowly contracted under mutual gravity about 4.6 billion years ago.
List the five main layers of the atmosphere, divided based on temperature, from lowest to highest altitude.
Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere.
Which is the lowermost layer of the atmosphere?
The Troposphere.
What is the average height of the Troposphere?
13 km (ranging from about 8 km near the poles to 18 km at the equator).
In which atmospheric layer is the ozone layer located?
The Stratosphere.
What happens to the temperature in the Mesosphere as altitude increases?
It decreases, reaching about -100°C at its upper boundary (around 80 km).
Between which altitudes is the Ionosphere primarily located?
Between 80 km and 400 km (above the mesopause).
What gives the Ionosphere its name and characteristic property?
It contains electrically charged particles known as ions.
