physical geo

Question 1

1.Which of the following types of erosion is responsible for the formation of Yardang?
A. Soil Erosion
B. Wind Erosion
C. Surface Erosion
 D. Streambank Erosion

2. Consider the following statements with reference to noctilucent clouds:
3. They are a form of cumulonimbus clouds formed in the upper part of the Troposphere.
4. They have been studied for centuries by meteorological research organisations

Answer 1

1.Yardangs are formed by wind erosion through the process of Abrasion. They are parallel troughs cut into softer rock running in the direction of the wind,
separated by ridges. Thus, the direction of the yardangs can indicate the direction of the wind. Winds abrasion excavates the bands of softer rocks into
long, narrow corridors, separating the steep-sided overhanding ridges of hard rocks called Yardangs. Option d describes the features of Yardangs

2.Temperature decreases with height in the mesosphere. The mesopause, the temperature minimum that marks the top of the mesosphere, is the coldest
place around Earth and has an average temperature of around −85 °C. At the mesopause, temperatures may drop to −100 °C. Due to the cold temperature
of the mesosphere, Water Vapor is frozen, forming ice clouds. These clouds are called noctilucent clouds. This implies that the noctilucent clouds are the
highest clouds in the Earth’s atmosphere, located in the mesosphere at altitudes of around 76 to 85 kilometers (47 to 53 mi). They are not part of
cumulonimbus clouds as cumulonimbus clouds form in the Troposphere and the lower parts of the stratosphere.

Question 2

Consider the following statements regarding Jet Streams:

1. Jet Stream is a band of fast-moving air usually found in the upper troposphere flowing from west to east.
2. Tropical Easterly Jet Stream occurs near the tropopause over Southeast Asia, India, the Arabian Sea, and Africa during summer.
3. Jet Streams bring about some moisture to the stratosphere, leading to the formation of noctilucent clouds.

Answer 2

Sub Tropical Jet Streams are best developed in winter and early spring. Their maximum speed approaches 300 knots which are associated with the merger with polar-front jets. A subsidence motion accompanies subtropical jets and gives rise to predominantly fair weather in areas they pass over. Sometimes they drift northward and merge with a polar-front jet.
Tropical Easterly Jet Stream occurs near the tropopause over Southeast Asia, India, and Africa during summer. This jet implies a deep layer of warm air to the north of the jet and colder air to the south over the Indian Ocean. The difference in heating and cooling and the ensuing pressure gradient is what drives this jet. Hence statement 2 is correct.
Polar-Night Jet Stream meanders through the upper stratosphere over the poles. They are present in the convergence zone above the sub-polar low-pressure belt.At times, Jet Streams bring about some moisture to the stratosphere, leading to the formation of Noctilucent clouds (tenuous cloud-like phenomena in the upper atmosphere which are made of ice crystals visible in a deep twilight)

Question 3

1. chinook- place, nature, also known as
2. foehn- place, nature
3. sirocco- place, nature, diff names
4. harmattan/doctors wind
5. mistral
6. bora
7. blizard

Answer 3

1. rockies, warm, ice eater
2. warm, slope of alps
3. warm dry dust laden , Sahara- Mediterranean, blood rain, egypt-khamsin
4. warm dry, blows from eastern part of sahara to west africa, brickfeilder- aus
5. cold, iberian peninsula, destroy grapes
6. cold wind, europe
7. cold wind