[Science 2] Meteorological Observations

Question 1

What is the Stevenson Screen?

Answer 1

A well-ventilated shelter to protect meteorological instruments

Question 2

What could be inside the Stevenson’s Screen?

Answer 2

Thermometers (ordinary, maximum/minimum);
Hygrometer / psychrometer; Barometer;
Thermograph (not a hygrograph bcz it’s larger and more sensitive)

Question 3

What instrument in the Stevenson’s Screen record the amount of water vapor?

Answer 3

Hygrometer

Question 4

What instrument in Stevenson’s Screen records relative humidity by using a wet and dry thermometer?

Answer 4

Psychrometer

Question 5

How can you calculate the relative humidity of the psychrometer by a wet and dry thermometer?

Answer 5

Difference in temperature (Dry - Wet)

Question 6

What instrument measures air pressure?

Answer 6

Barometer

Question 7

What unit is used for air pressure in weather reports?

Answer 7

hPa (hectopascals)

Question 8

What is the atmospheric pressure at sea level?

Answer 8

1013 hPa

Question 9

What instrument records temperature and humidity (or dew point)?

Answer 9

Thermo-Hygrograph

Question 10

What is wind direction measured using?

Answer 10

Wind vane

Question 11

What is wind speed measured using?

Answer 11

Anemometer

Question 12

Why are instantaneous values used in an anemometer?

Answer 12

Winds are constantly changing (average value over past 10 minutes)

Question 13

How many cardinal directions does meteorologists use to describe wind?

Answer 13

16 (wind is named for the direction it is blowing from)

Question 14

What shows the strength of the wind?

Answer 14

Beaufort Scale

Question 15

In a cloud cover, how much is sunny, clear, and cloudy?

Answer 15

Clear: 0-1
Sunny: 2-8
Cloudy:9-10

Question 16

What is rain observed using?

Answer 16

Rain gauge (can also measure snow after its melted down)

Question 17

What does “1 mm of precipitation” mean?

Answer 17

1 L of rain fell over an area of 1 m^2

Question 18

What are constant pressure areas described as in weather charts?

Answer 18

Isobars

Question 19

What does the isobars connect?

Answer 19

Connect areas with the same pressure (that is why closer lines –> wider pressure difference –> wind stronger)

Question 20

Isobars are drawn every ____hPa

Answer 20

4

Question 21

What are the steps you take to figure out the path of wind in weather charts?

Answer 21

The wind blows parallel to isobars and the direction itself by the Coriolis effect. However, since there is friction between the Earth’s surface, it will cause the wind to deflect its intended path by 30 degrees.