Weather and climate chapter 2

Question 1

WHat is weather?

Answer 1

Weather is the condition of the atmosphere at a particular place and time. The atmosphere is a layer of air surrounding the Earth. The weather affects how we live from day to day

Question 2

What is climate?

Answer 2

Climate is the average condition of the atmosphere of a specific place over a long period of time, usually over 30 years.

Question 3

What are the elements of weather.

Answer 3

The weather can be described in terms of six elements called the elements of weather.
This six elements are:
1)Temperature
2)Relative humidity
3)Clouds
4)Rainfall
5)Air pressure
6)wind

Question 4

Elaborate on the first element of weather: Temperature.

Answer 4

Temperature is the degree of hotness or coldness of a place. This is determined by the energy from the sun which reaches the Earth. neergy from the sun mostly travels through the atmosphere and is abosrbed by the Earthś surface. This causes the earthś surface to warm up, which in turn heats the atmosphere.

Question 5

How is temperature measured?

Answer 5

temperature is regularly measured nad recorded around the world. temperature is measured in degrees Celcius (C) using an analougue or digital thermometer. To measure the maximum and minimum temperatures, a maximum and minimum thermometer is used. In the study of weather, high temperatures are defined as anything above 20C and low temperatures as anything below 10C

Question 6

Define mean daily temperature.

Answer 6

the Sum of hourly temperatures divided by 24 hours.

Question 7

Define Diurnal temperature range

Answer 7

Diurnal temperature range

Question 8

Define mean monthly temperature

Answer 8

Average of the daily temperatures recorded in a month

Question 9

Define annual temperature

Answer 9

Average temperature recorded in a year.

Question 10

Define Annual temperature range

Answer 10

Difference between the maximum and minimum mean monthly temperatures recorded in a year.

Question 11

WHat is latitude?

Answer 11

Latitude is the distance of any point on the earth measured north or south from the Equator. Latitudes are imaginary horizontal lines running from east to west around the earth and are measured in degrees.

Question 12

Why are some places hotter or colder on earth due to latitude?

Answer 12

A place near to the equator has higher temperatures because the places nearer the Equator receive the sunś rays at a higher angle of incidence and thus the sunś rays are more concentrated on these areas. The rays also have a shorter distance to travel through the atmosphere.
Places near the Poles have lower temperatures because places closer to the Poles receive the sunś rays at an angle, that is, at a lower angle of incidence. The rays have a larger area to heat and a longer distance to travel through the atmosphere.

Question 13

What are the factors that affect temperature?

Answer 13

Latitude, altitude, distance from the sea and cloud cover.

Question 14

What is altitude?

Answer 14

Altitude refers to the height of a place above sea level. The temperature decreases 6.5C with every 1000 meteres increase in altitude.

Question 15

Why are temperatures higher with lower altitudes?

Answer 15

Temperatures are higher at lower altitudes because the air closest to the earthś surface heats up first from the sunś shortwave radiation before the heat spreads upwards in long waves to heat the atmosphere. Longwave radiation emitted by the earth is absorbed by greenhouse gases like carbon dioxide in the atmosphere. Air is denser at lower altitudes. Denser air at sea level is able to bsorb and retain more heat than the less dense air at higher altitudes.

Question 16

How does distances form sea affect temperature?

Answer 16

The sea heats up and cools down more slowly than the land. Thus, summer temperatures in coastal areas do not go up so high, and winter temperatures do not drop so low as in inland areas. Places near the sea experience smaller ranges of temperature compared to areas further inland. Thus, coastal areas experience cooler summer and warmer winter compared to inland areas. This is due to the maritime effect.

Question 17

What is the temperatures like in inland areas?

Answer 17

IN inland areas, temperatures are more extreme. Temperature ranges are bigger because there is no moderating effect from the sea. In summer, the land heats up quickly and in winter the land loses heat quickly. Thus, inland areas experience warmer summers and cooler winter compared to coastal areas. This is the continental effect.

Question 18

What is cloud cover?

Answer 18

Cloud cover is the extent of the sky that is covered by clouds. The amount of cloud cover influences the temperatures on the earthś surface in the day and at night. More cloud cover results in smaller differences between day and night temperatures, so the diurnal temperature range is smaller.

Question 19

What happens to the temperature during the day with cloud cover?

Answer 19

During the day, clouds reflect a large amount of the sunś energy back to space. This will keep the earthś surface cool. At the same time, clouds also absorb heat radiated from the earthś surface and prevent it from escaping into space. The air near the earthś surface is thus kept warm at night.

Question 20

What happens to the temperature during the night with the absence of cloud cover?

Answer 20

During the night, the absence of clouds allows large amounts of the sunś energy to reach the earth. The earthś surface will be heated up quickly so the air near the earthś surface is warmer. During the night, the absence of clouds allows more heat radiated from the earthś surface to escape into space. The air near the earthś surface is thus cooler at night.

Question 21

How does the maritime effect affect temperature?

Answer 21

the maritime effect is the effect the large ocean bodies have on the climate of coastal areas.
It causes coastal areas to have a smaller annual temperature range. During summer, the air over the sea is cooler than the air over the land
this is because land heats up more quickly while the sea heats up more slowly.
The cooler air over the sea helps lower the temperature of the coastal. Coastal areas are therefore cooler than places further inland.
During winter, the air over the sea remains warmer than the air over the land because the sea cools more slowly than the land
the Warmer air over the sea increases the temperature of coastal areas. In comparison, inland areas are cooler.
Due to the maritime effect, coastal areas experience cooler summers and warmer winters, and a smaller annual temperature range than inland areas.

Question 22

What is relative humidity?

Answer 22

Relative humidity is the ratio between the actual amount of water vapour present in a mass of air and the maximum amount of water vapour the air could hole at a given temperature.

Question 23

How is relative humidity measured?

Answer 23

Relative humidity is measured using a psychrometer, which consists of a wet bulb thermometer and a dry bulb thermometer.

Question 24

What is the formula to calculate relative humidity?

Answer 24

Actual amount of water vapour in the air (g/m3)/ Maximum amount of water vapor the air can hold (g/m3) *100

Question 25

How does temperature increase as relative humidity decreases?

Answer 25

The amount of water vapour in the air affects relative humidity.
Relative humidity also caries with temperature. When temperature increases, the amount of water vapour in the air stays the same, but the rise in temperature makes air more able to hold water vapour. Thus relative humidity decreases as temperature increases. when the air holds the maximum amount of water vapour it can hold, it is said to be saturated.

Question 26

When does saturation occur?

Answer 26

Saturation occurs when relative humidity is at 100%. The temperature at which saturation is known as the dew point temperature. Condensation first starts to occur at dew point temperature. Condensation is a process in which water vapour changes to a liquid form by cooling.

Question 27

What will happen when relative humidity is at 100% and more evaporation takes place after that?

Answer 27

Clouds will be formed when dew point temperature is reached.

Question 28

What is rainfall?

Answer 28

Rainfall is water that falls from the atmosphere to the surface of the earth
High rainfall is anything above 1500mm while low rainfall is anything below 250mm

Question 29

How is rainfall measured?

Answer 29

rainfall is measured using rain gauge

Question 30

Where do you place a rain gauge?

Answer 30

A rain gauge must be placed in an open and unblocked area. There should be no obstructions near the rain gauge which may affect amount of rainfall to be collected. It should be placed where the rain gauge could be partially embedded into the ground to prevent it from being toppled over by strong winds, animals and humans.
Hence, concrete ground is not ideal to place a rain gauge as rainwater that splashes onto the ground may enter the rain gauge, giving inaccurate measurement.

Question 31

Where should a rain gauge not be placed?

Answer 31

The rain gauge shoukd not be placed near or under a tree as raindrops on leaves and branches may drip into the rain guge after the rain has stopped. In addition, being placed under a tree or sheltered area will prevent rainwater from entering the rain gauge. All these will result in an inaccurate reading.
The water in the glass jar will then be emptied into a measuring cylinder

Question 32

How many types of rainfall are there?

Answer 32

Convectional rainfall and relief rainfall (also known as orographic rainfall)

Question 33

Elaborate on convectional rainfall.

Answer 33

Convectional rainfall occurs when the earthś surface is heated intensively. Hence, this form of rain is common in the tropics which receive a great amount of sunlight.
As the sunś energy heats up the earthś surface, the earm surface heats the air around it.
the air becomes unstable, causing it to expand and rise.
As the air rises, its temperature begins to drop. When the rising air cools to the dew point temperature, condensation occurs and clouds are formed.
When the water droplets in the clouds become large and heavy enough, they fall as rain. It is usually associated with lightning and thunder. Hence, cumulonimbus clouds are usually associated with convectional rain.

Question 34

Elaborate on Relief rainfall

Answer 34

Relief rainfall (also known as orographic rainfall) occurs when moist and warm air is forced to rise over landforms such as a mountain range. Most air passes over the sea and arrives at the coast. The air then rises up the windward side of the mountain and is forced to cool. when the temperature of the air reaches the dew point, condensation occurs and clouds form. When the water droplets become large and heavy enough, they fall as rain on the windward side where air had risen up.

Question 35

What is air pressure?

Answer 35

Air pressure: Force exerted on a unit area of the earthś surface by the weight of a column of air above it.

Question 36

How is air pressure measured?

Answer 36

air pressure is measured in millibars (mb) using a barometer.
-Air pressure decreases as altitude increases. As air is less dense at higher altitudes, hence the weight of the column of air at higher altitudes is lower.

Question 37

.What is the average sea level value of air pressure?

Answer 37

1,013 mb. Air pressure is considered high if it is above the sea level value, and low if it is below the sea level value.

Question 38

What is wind?

Answer 38

Air moves from an area of high pressure to an area of low pressure. This movement of air is known as wind.

Question 39

What do you call the difference in air pressure between two locations?

Answer 39

Pressure gradient. The greater the difference in air pressure (steeper pressure gradient), the faster the wind speed.

Question 40

How is wind described?

Answer 40

Wind is described in terms of speed, direction and frequency.

Question 41

What is wind speed?

Answer 41

Wind speed is the rate at which air is moving and is measured in kilometeres per hour using an anemometer. The cups are used to capture the wind. The moving force of the wind will then spin the cups and the speed will be reflected in the meter attached below.

Question 42

Where to place an anemometer?

Answer 42

An anemometer needs to be placed preferably at a high and unblocked area in order to measure wind speed accurately. Usually located on rooftops.

Question 43

What is wind direction?

Answer 43

Wind direction refers to the direction from which the wind blows

Question 44

How do you determine the wind direction?

Answer 44

A wind vane is used to determine the wind direction. The wind vane points to the direction the wind is blowing from. Wind vane should be placed at a high and unblocked area. Usually on rooftops.

Question 45

What is wind frequency?

Answer 45

Wind frequency refers to the percentage of time the wind blows from a particular direction. Winds that blow most frequently from a specific direction are called prevailing winds.

Question 46

What are prevailing winds?

Answer 46

Winds that blow most frequently from a specific direction are called prevailing winds.

Question 47

How can wind directiion and frequency be recorded?

Answer 47

Wind direction and frequency can be recorded using wind roses.

Question 48

Elaborate on Land breezes.

Answer 48

Land breezes are local winds that occur in coastal areas. These winds lower the temperature of coastal areas during the day and regulate the temperature during the night, leading to a smaller diurnal temperature range in these areas. A land breeze is a wind that blows from land to sea. Land breeze occurs during the night
Land loses heat faster than water
Higher temperatures over sea than land
Pressure is lower over sea than land
Wind blows from high pressure area over the land to low pressure area over the sea.

Question 49

Elaborate on sea breezes.

Answer 49

A sea breeze is a wind that blows from sea to land.
A sea breeze occurs during teh day
Land absorbs heat faster than water
Higher temperatures over land than sea
Pressure is lower over land than sea
Wind blows from high-pressure area over the sea to low-pressure area over then land.

Question 50

Elaborate on monsoon winds.

Answer 50

Monsoon winds are regional wind patterns that reverse direction seasonally
this brings seasonal changes in precipitation
The levels of precipitation can either increase or decrease with the occurence of monsoons, and lead to wet or dry seasons
Monsoon winds and other winds are affected by the Coriois effect, which is a force produced by the earthś rotation.

Question 51

Elaborate on the Coriolis effect

Answer 51

As the earth rotates, the Coriolis effect causes the bending or deflection of winds.
The Coriolis effect is strongest near the poles, weak in the tropics and not felt at the Equator
In the norther hemisphere, the Coriolis effect deflects winds to the right while it has the opposite effect in the southern hemisphere, as winds are deflected to the left.
Monsoons occur in a number of locations around the world
The major monsoons affect asia and asutralia

Question 52

What are the two types of monsoons?

Answer 52

Southwest monsoon and Northeast monsoon

Question 53

Elaborate on the southwest monsoon

Answer 53

• Occurs betwene June and september
• Summer in norther hemisphere, winter in the southern hemisphere.
• Higher pressure in the southern hemisphere will generate southeast winds blowing towards the lower pressure area in the norther hemisphere.
• As the winds cross the equator, they change direction (southwest) due to Coriolis effect
• India is also affected by monsoons. The southwest monsoon between June and september supplies nearly 80 percent of Indiaś annual rainfall.

Question 54

Elaborate on the northeast monsoon

Answer 54

• occurs between october and febuary
• Summer in southern hemisphere, winter in the norther hemisphere.
• Higher pressure in the norther hemisphere will generate northeast winds blowing towards the lower pressure area in the southern hemisphere.
• As the winds cross the equator, they change direction(northwest) due to Coriolis effect
• For example, SIngapore commonly experiences high rainfall in december because of the northeast monsoon but Indian experiences low rainfall at this period.

Question 55

How many climatic types are there?

Answer 55

3 key climate types:

• Equatorial climate
• Monsoon climate
• cool temperate (marine west coast)

Question 56

Elaborate on the equatorial climate.

Answer 56

• high temepratures, hgih rainfall, high humiudity all year around.
• Dominantly convectional rain with large cloud
• Cover: small diurnal range
• Places are located between 10 degrees north and south of the equator

Question 57

Elaborate on the monsoon climate.

Answer 57

-High temeperatures, high rainfall, high humidity all year around.
-Distinct wet and dry season
Moderate temperature range (7.5C)
-Located between 5 degrees and 25 degrees north and south of the equator

Question 58

Elaborate on the Cool temperate climate (Marine west-coast)

Answer 58

• 4 distinct seasons due to tilt of the earth and the revolution around the sun
• Mild winters and cool summers. during winter, these places have shorter days and receive less energy from the sun, resulting in the large annual temperature range of 25C with temperatures ranging from -3C to 22C throughout the year
• No distinct wet or dry seasons. Rainfall in evenly distributed but total annual rainfall is lower than in places with equatorial and monsoon climates. total rainfall range between 300mm and 900mm
• Located between 45degrees and 60 degrees north and south of equator