Clouds and Precipitation #2

Examine the accompanying table. Calculate how much less water is contained in saturated air at a polar location with a temperature of -10°C compared to a tropical location with a temperature of 40°C.

45 grams

At which of the placemarks, A-E, would you expect to find the greatest potential evaporation rates combined with low annual precipitation?

C

The state of matter in which water is compressible.

Gas (vapor)

The state of matter in which water molecules are most energetic.

Gas (vapor)

In this part, you will explore how relative humidity affects you every day with real-world examples. The air temperature and the relative humidity of the air can often impact the perceived temperature one feels, the rates and amount of condensation, or how quickly food spoils. To better understand these concepts, consider the following scenarios. You will sort each real-world scenario with its respective level of humidity.

High relative humidity: -Jet airplane condensation trails (i.e., human-made cirrus clouds) form behind the engines of a jet and linger in the sky for hours. -Bathroom mirror gets foggy after taking a shower -Dew deposits on your vehicle early in the morning. -Sweating profusely and your shirt remains soaked with sweat. Low to Average Relative Humidity: -Feeling comfortable outside along a lake shore, even though it is a hot summer day. -Wet clothes hanging on a line or rack dry quickly -A food storage container which has fresh food with no mold.

What happens to sensible heat energy in water when the water evaporates?

It becomes latent energy in air when water molecules containing the heat break free from an evaporating surface to become a gas.

Based on the data in the Relative Humidity folder, at which location would you expect to find the highest relative humidity?

Jackson, Mississippi

Which of the following relationships is correct?

Relative humidity increases: a decrease in temperature without a change in the amount of water vapor in the atmosphere.

The state of matter in which water molecules vibrate about fixed locations.

Solid (ice)

The state of matter of frost on grass.

Solid (ice)

Based on the evidence in the Water Vapor layer, which of the following statements is most accurate?

Summer heating in northern Canada increases the temperature of the land, increasing the capacity of the overlying air to hold water vapor relative to the air over the colder water in Hudson Bay

The way relative humidity can change with temperature over the course of a typical day (autumn) is shown in the figure below. In the figure, the air temperature increases during the daytime as the Sun warms Earth, and it cools during the nighttime after the Sun has set. Assume that the actual amount of water vapor in the air (expressed as specific humidity here) is 10 g/kg, and that it remains constant over the course of the days. The water-vapor capacity (expressed as the saturation-specific humidity) at various temperatures (needed to calculate relative humidity) is provided in the table attached to the image below. You will label the respective relative humidity. Each relative humidity label is associated with the temperature indicated on the curve.

Top: 47.9%, 42.5% Bottom: 69.1%, 89.0%

Which of the following statements best explains the formation process of the contrails seen in the Contrails layer?

Warm, moist air from aircraft exhaust interacts with the surrounding cool air, resulting in condensation

Latent heat is _______ during glacial melt.

absorbed

The latent heat released during rainfall is _______ the latent heat released during snowfall.

less than

The state of matter in which water is densest.

liquid (water)

Latent heat released during dew formation is ______ the latent heat required for water to freeze from its liquid state.

more than

Latent heat is _________ during frost formation.

released

Latent heat absorbed during evaporation of lake water is _______ the latent heat released during fog formation.

same as

When ocean and sea surfaces heat up sufficiently, evaporation occurs. The warm vapor rises into the atmosphere, then cools and condenses, releasing its stored latent heat. Existing storms and tropical cyclones—which are called hurricanes in the Atlantic Ocean and typhoons in the Pacific and Indian oceans—gather up the released heat, which gives them greater energy and strength. Higher values of latent heat of evaporation indicate greater evaporation per unit area. This in turn signals the release of greater amounts of latent heat when condensation occurs. Therefore, latent heat of evaporation is one factor affecting the strength of tropical cyclones—the higher the values of latent heat of evaporation, the more powerful a storm. The map shows isolines indicating areas with the same values of latent heat of evaporation across the globe. Isolines, which are very useful in geographic and geologic studies, join areas of the same value, such as height or heat.Assume that latent heat of evaporation is the only determining factor affecting cyclone strength, and that all target areas experience cyclones. The key below the map provides a general idea of the range of latent heat of evaporation within which a target area falls—for example, the deepest blue indicates latent heat of evaporation between 15 and 25 watts per square meter. Compare the isoline values indicating the amount of latent heat of evaporation around each target area to identify the following: The target area that is most likely to experience the strengthening of cyclones The target area that is second most likely to experience the strengthening of cyclones The target area that is third most likely to experience the strengthening of cyclones The target area that is least likely to experience the strengthening of cyclones Note that you will use the value of the isolines and not the color on the maps to help determine the relative strengths of cyclones. This is because a single color code on the map represents a range of isoline values.

top-bottom: Second most likely, third most likely, least likely right: most likely