Author Question: Why are large snowflakes usually observed when the air temperature near the ground is just below ... (Read 63 times)

HudsonKB16

  • Hero Member
  • *****
  • Posts: 535
Why are large snowflakes usually observed when the air temperature near the ground is just below freezing?
  What will be an ideal response?

Question 2

How does the ice-crystal (Bergeron) process produce precipitation? What is the main premise describing this process?
  What will be an ideal response?



mk6555

  • Sr. Member
  • ****
  • Posts: 310
Answer to Question 1

ANSWER: Snowflakes that fall through moist air that is slightly above freezing slowly melt as they descend. A thin film of water forms on the edge of the flakes, which acts like glue when other snowflakes come in contact with it. In this way, several flakes join to produce giant snowflakes often measuring several inches or more in diameter. These large, soggy snowflakes are associated with moist air and temperatures near freezing. However, when snowflakes fall through extremely cold air with a low moisture content, small, powdery flakes of dry snow accumulate on the ground.

Answer to Question 2

ANSWER: The main premise is that the saturation vapor pressure just above a water surface is greater than the saturation vapor pressure above an ice surface. This difference in vapor pressure causes water vapor molecules to move (diffuse) from the droplet toward the ice crystal. The removal of vapor molecules reduces the vapor pressure above the droplet. Since the droplet is now out of equilibrium with its surroundings, it evaporates to replenish the diminished supply of water vapor above it. This process provides a continuous source of moisture for the ice crystal, which absorbs the water vapor and grows rapidly. Hence, during the ice-crystal (Bergeron) process, ice crystals grow larger at the expense of the surrounding water droplets.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Vaccines prevent between 2.5 and 4 million deaths every year.

Did you know?

Asthma-like symptoms were first recorded about 3,500 years ago in Egypt. The first manuscript specifically written about asthma was in the year 1190, describing a condition characterized by sudden breathlessness. The treatments listed in this manuscript include chicken soup, herbs, and sexual abstinence.

Did you know?

The average older adult in the United States takes five prescription drugs per day. Half of these drugs contain a sedative. Alcohol should therefore be avoided by most senior citizens because of the dangerous interactions between alcohol and sedatives.

Did you know?

Cutaneous mucormycosis is a rare fungal infection that has been fatal in at least 29% of cases, and in as many as 83% of cases, depending on the patient's health prior to infection. It has occurred often after natural disasters such as tornados, and early treatment is essential.

Did you know?

Critical care patients are twice as likely to receive the wrong medication. Of these errors, 20% are life-threatening, and 42% require additional life-sustaining treatments.

For a complete list of videos, visit our video library