Rainfall worksheet

Using Fig. 1, explain the formation of relief rain.                                                                             [4]

• Warm, moist air from the sea is forced to rise. Air cools as it rises up the mountain.
• At dew point, condensation occurs and clouds are formed.
• When water droplets are heavy and large enough, they fall as rain on the windward side.
• By the time the air moves over to the leeward side, the air is dry and no rain falls.

CONVECTIONAL RAIN

 

Using Fig. 2, explain the formation of relief rain.                                                                             [3]

• The sun’s energy reaches the earth’s surface in the form of solar radiation.
• The earth’s surface is heated by the sun’s energy and also heats up the surrounding air.
• Air expands and rises.
• As the air rises, it cools. When it reaches dew point, condensation occurs.
• Cumulonimbus clouds are formed.
• When water droplets becomes large and heavy enough, they fall to the ground as rain.

Relative humidity lesson

Questions and Answers

1) What is the difference between high and low relative humidity?

- High RH : (air is saturated with water vapour, may rain soon)
- Low RH : (air has very little water vapour, feels dry) 


2) How is relative humidity calculated?
- Take the wet and dry bulb temperature readings 
- Find the wet bulb depression (Dry minus wet )
- Match it on the RH table
- Answer is in %

3) What is the relationship between RH and temp?
- Inverse
- When RH increase, temperature decrease
- When RH decrease, temperature increase

Individual video assignment

Instructions

• ·                   Choose 1 topic Below and created a video to answer it
• ·        Duration of the video MUST be less than 5 minutes
• ·        Video can be edited by cropping or adding of subtitles
• ·        Resources can be used from the textbook or the Internet
• ·        Dateline : 2 Feb Thur
• ·        Submission method : email to seetoh_sijia@moe.edu.sg OR save in thumbdrive

Marks allocation

	Marks (10m)
Relevant content	2m
Clarity of video	2m
Summary of points	2m
Creativity of the video	2m
Examples provided	2m

Topics

1. How does human activities affect global climate change?

2. What are the impact of increasing global temperatures? 

3. What are the international policies created to reduce carbon dioxide level?

4. What are countries like Singapore or India doing to reduce Greenhouse gases?

Rainfall videos

Relief rain : https://www.youtube.com/watch?v=RkgThul2El8

Convectional rain: http://www.tubechop.com/watch/8800235

Stevenson screen

a)     Identify the 6 characteristics of the Stevenson Screen.                                                                                [6]

Amendment: 1.5m height(Follow textbook)

Edmodo Group Code

sz4u5j

Class Test 1

Date :6 Feb Mon

Venue: Classroom

Topic: Weather and Climate (Definition, Temperature, GI - Instruments)

Distance from the sea - Answers

1)     Fig. 1 shows the weather conditions of two locations with similar latitude.

LOCATION	LATITUDE	DISTANCE FROM SEA	TEMPERATURE
ANCHORAGE	61.1919° N	1 KM	20°C
FAIRBANKS	64.8378° N	420KM	40°C

Fig. 1

a)     Explain why Anchorage and Fairbanks have extreme temperatures although they are located along similar line of altitude.                                                                                                                                              [4]                       

-        Both Anchorage and Fairbanks have similar line of latitude at around 61.2 to 65 ° N so their temperature should be similar.

-        However Fairbanks is further away from the sea at 420km in distance. This implies that it is located inland and may be surround by continent which causes temperature to be higher.

-        Anchorage is near to the sea as it is 1km from the coastline. This implies that it might have sea and land breezes that may help to lower the temperature.

-        Therefore the presence of maritime effect causes the extreme temperature difference.

Relative humidity past year questions

Relative humidity     

Video 1: 

http://www.tubechop.com/watch/8792291

Q1: What is the difference between high and low relative humidity?

Video 2:

http://study.com/academy/lesson/what-is-humidity-definition-measurements-effects.html

Q2: How is relative humidity calculated?

Figure 1:

Q3: What is the relationship between Relative humidity and temperature?

1.		A group of students selected 12 sites around their school campus to carry out an investigation to test the given hypothesis: Hypothesis: Temperatures are higher nearer to buildings. They measured the distance from each site to the nearest building. At each site they measured temperature and relative humidity. Fig. 1 shows the temperature and relative humidity readings at the twelve sites. Site A B C D E F G H J K L M Distance from  Buildings (m) 32 2 3 5 1 17 9 2 10 24 30 42 Temp (0C) 28.2 28.5 29.1 28.1 28.9 28.2 28.4 28.8 28.6 28.3 28.1 28.0 Type of ground surface Grass Bush Con-crete Tar-mac Con-crete Trees Next to water Con-crete Grass Tar-mac Grass Tar-mac Relative Humidity (%) 73 77 73 73 76 73 75 77 75 77 76 75 Fig. 1
	a	Using Fig. 1, suggest another suitable hypothesis for the class to investigate.
		·        Relative humidity is affected by the type of ground surface ·        Temperature is affected by the type of ground surface                 Accept any other plausible answer
	b	Using Fig. 1, identify the instruments needed in this investigation.
		·        Digital thermometer ·        Hygrometer
	c	Suggest three reasons why temperatures vary around the school campus.
		·        Buildings / tarmac / concrete absorb / store heat from sun or internal heating system ·        Buildings radiate heat for small distance around them thus temperatures are higher nearer to buildings ·        Aspect / south facing / north facing / faces sun will have higher temperature ·        Sun: shade from sun/ shade by trees / buildings will have lower temperature ·        Wind: Shelter from wind / exposure to wind / shelter by trees/ buildings will result in different temperature ·        Different types of surface / e.g. some on grass and concrete
		3         Fig.3 shows an example of how relative humidity is calculated with a Relative Humidity table. a)      With the aid of Fig. 3, calculate the relative humidity for the following readings: ·         Temperature difference = 1°C  Relative Humidity = 91% [2] b)      Describe the advantages of using a digital thermometer and a hygrometer over a maximum-minimum thermometer and a wet and dry bulb thermometer.                           [4] ·         The digital thermometer and hygrometer can give instant readings. Thus, one does not have to work out the answer. ·         Easy / clear to read with a large digital readout  ·         One does not need to learn how to read a thermometer. ·         Parallax errors can be avoided since one does not have to read off thermometer. ·         Since exact figures are given, the measurements are more accurate. ·         Portable / can be used at more than one site ·         Safer to use as there is no mercury content [3]

Factors affecting temperature

Use the internet to answer the following question:

1) What are lines of latitude?
2) How does temperature changes at different altitude?
3) What is maritime effect?
4) What is continental effect?
5) Does cloud cover makes temperature warmer or cooler?

Assessment plan

Term 1
Common test - CA1 (10%)

Class Test (5%)
E learning (5%)

Term 2
Mid year exam (20%)

Term 3
Common Test (10%)

Class Test (5%)

Term 4
End of year exam (30%)

ASK (5%)
Other assessments (10%)