Earth's Atmosphere Review

What is the most abundant gas in Earth's atmosphere?

• Oxygen

• Argon

• Carbon Dioxide

• Nitrogen

Answer explanation

Nitrogen is the most abundant gas in Earth's atmosphere, making up about 78% of it. In contrast, oxygen is around 21%, while argon and carbon dioxide are present in much smaller amounts.

Which layer of the atmosphere is the least dense?

• Troposphere

• Stratosphere

• Thermosphere

• Exosphere

Answer explanation

The exosphere is the outermost layer of the atmosphere and has the lowest density, as it gradually transitions into outer space where particles are extremely sparse.

In which direction does the moving force of air flow?

• From low pressure to high pressure.

• From high pressure to low pressure.

Answer explanation

Air flows from high pressure to low pressure due to the natural tendency to equalize pressure differences. This movement is what creates wind and is fundamental to understanding weather patterns.

Tags

NGSS.MS-ESS2-5

Which statement best describes how temperature, humidity, and pressure vary within an air mass?

• The temperature and humidity are basically the same throughout, but the pressure varies.

• The pressure and humidity are basically the same throughout, but the temperature varies.

• The temperature, humidity, and pressure are basically the same throughout an air mass.

• All three factors vary wildly within a single air mass.

Answer explanation

The correct choice states that temperature, humidity, and pressure are basically the same throughout an air mass. This uniformity is characteristic of air masses, which maintain consistent properties over large areas.

Tags

NGSS.MS-ESS2-5

Which conditions are usually the effect of a low air pressure system?

• Clear, dry weather.

• Cloudy, wet weather.

• Hot, sunny days.

Answer explanation

A low air pressure system typically leads to rising air, which cools and condenses, resulting in cloudy and wet weather. This is why 'Cloudy, wet weather' is the correct choice, as opposed to clear or hot conditions.

Tags

NGSS.MS-ESS2-5

NGSS.MS-ESS2-6

Which word pair best describes the result of tropical continental air in the summer?

• Cool and humid

• Cold and stormy

• Warm and dry

• Cold and dry

Answer explanation

Tropical continental air in summer is characterized by warm temperatures and low humidity, leading to dry conditions. Therefore, the best description is 'Warm and dry', as it accurately reflects the typical weather patterns.

Tags

NGSS.MS-ESS2-5

What do high pressure systems usually cause?

• Rain and storms

• Cloudy and unsettled weather

• Clear, dry weather

• Strong, gusty winds

Answer explanation

High pressure systems are associated with descending air, which inhibits cloud formation and leads to stable atmospheric conditions. This typically results in clear, dry weather, making it the correct choice.

Tags

NGSS.MS-ESS2-5

Which statement best describes the relationship between changes in air pressure and wind speeds?

• The greater the pressure difference, the faster the wind speed.

• Wind speed is not affected by air pressure changes.

• Higher air pressure always results in higher wind speeds.

• Wind speed decreases with increasing air pressure.

Answer explanation

The correct statement is that the greater the pressure difference, the faster the wind speed. Wind moves from high to low pressure, so a larger difference results in stronger winds.

Tags

NGSS.MS-ESS2-5

What would cause rain showers to continue over a particular area for several days?

• A cold front

• A warm front

• A stationary front

Answer explanation

A stationary front occurs when warm and cold air masses meet but neither moves, leading to prolonged rain showers as moisture is continuously lifted over the area. This is why rain can persist for several days.

Tags

NGSS.MS-ESS2-5

A warm front is heading toward Chicago. Which type of weather would one expect when it arrives?

• Snow and ice

• Hot and sunny

• Light rain or drizzle

Answer explanation

A warm front brings warmer, moist air that rises over cooler air, leading to cloud formation and precipitation. Therefore, when it arrives in Chicago, one can expect light rain or drizzle.

Tags

NGSS.MS-ESS2-5