Weather and Humidity Concepts

These flashcards cover key concepts on humidity, fog formation, lifting mechanisms, and the related impact on weather patterns.

What does relative humidity express?

Relative humidity expresses the vapor content against vapor capacity of the air.

What is the relationship between temperature and relative humidity?

Temperature and relative humidity are inversely related; as temperature increases, relative humidity decreases, provided specific humidity stays constant.

What happens to air as it rises in the atmosphere?

As air rises, it cools, potentially reaching a temperature where condensation occurs, forming clouds or precipitation.

What are the two mechanisms to reach saturation in the air?

To reach saturation, either the temperature is lowered (shrinking the bucket) or water vapor is added.

What is radiation fog?

Radiation fog forms when the ground cools overnight, causing the air near the surface to reach the dew point temperature.

What is the definition of dew point temperature?

The dew point temperature is the temperature at which air reaches saturation, and water vapor begins to condense.

What is the process of evaporative cooling as it relates to sweating?

Evaporating sweat cools the body as the energy from the body is used to turn liquid water into vapor.

What is convective lifting?

Convective lifting is the rise of warm air due to its lower density compared to surrounding cooler air.

What is orographic lifting?

Orographic lifting occurs when an air mass is forced to rise over topography, such as mountains, cooling and potentially causing precipitation.

What effect does sinking air have on humidity?

Sinking air warms and reduces relative humidity, resulting in drier conditions.

What is the rain shadow effect?

The rain shadow effect occurs when mountains block moist air, causing precipitation on the windward side and dry conditions on the leeward side.

What is advection fog?

Advection fog forms when warm air moves over a cooler surface, cooling the air to the dew point.

How does the latent heat affect cooling rates in the atmosphere?

When condensation occurs, latent heat is released, slowing the rate of cooling above the lifting condensation level (LCL).

What is the lifting condensation level (LCL)?

The lifting condensation level is the height at which air cools to its dew point and condensation begins to occur.

What is evaporation fog?

Evaporation fog forms when warm, moist air from a body of water is cooled to the dew point by colder air.

What does the term 'specific humidity' refer to?

Specific humidity refers to the actual amount of water vapor present in the air, usually expressed in grams of water vapor per kilogram of air.

What is the significance of humidity in weather processes?

Humidity plays a critical role in temperature regulation, energy transfer, and precipitation formation.

Why do we often observe fog in the mornings?

Fog is commonly observed in the mornings because temperatures are often lower during this time, allowing air to reach saturation more easily.