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Temperature:
Formulas to Remember:

1) Mean Daily Temperature * Mean - Average

2) Daily temperature range Range - Max — Min
3) Mean monthly temperature
4) Monthly temperature range
5) Mean annual temperature
6) Annual temperature range

Cloud cover Latitude Altitude Distance from sea

Latitude: distance of any point on the earth measured north or south from the equator

Places that are further from the equator:

> Lower temperature as solar radiation is spread over larger area and less sun rays are absorbed by
the atmosphere

Places nearer the equator:

> Higher temperature as solar radiation is concentrated over a smaller area and more sun rays are
absorbed by the atmosphere

At higher latitudes, temperature decreases due to lower solar angle

At lower latitudes, temperature increases due to higher solar angle

Altitude: height of a place above sea level

Temperature decreases 6.5 degrees every 1000m

Highland -> Lower temperature as there is less dense air unable to absorb more heat from shortwave
radiation

Lowland -> Higher temperature as there is more dense air able to absorb more heat from shortwave
radiation
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Distance from the sea:

* Sea will always lose heat/gain heat SLOWER than land

Maritime effect (Places closer to coast)

> Coastal areas have lower annual temperature range
> Cooler summer as the sea heats up slower
> Warmer winter as sea loses heat slower

Eg. Anchorage
- Maximum summer temperature of 15 degree celsius
- Minimum winter temperature of -9 degree celsius
- Range is 24 degree celsius
- Anchorage has cooler summer and warmer winter
Continental effect (Places further from the coast)
> Inland areas have greater annual temperature range
> Warmer summer as land heats up faster
> Cooler winter as land loses heat faster

Eg. Fairbanks city in Alaska

- Max summer temperature of 16 degree celsius
- Min winter temperature of -24 degree celsius
- Range is 40 degree Celsius
- Fairbanks City has warmer summer and cooler winter

Cloud Cover:

Places with lack of cloud cover

DAY:
> higher amount of solar radiation able to reach the surface leading to higher temperature

NIGHT:
> Due to the lack of cloud cover, allows heat to escape into space more easily and causing a sharp
decline in temperature

Eg. Sahara Desert

Day - 40 degrees
Night - 15 degrees
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Places with cloud cover

DAY:
> Cloud cover reflect part of solar radiation back into space, lesser solar radiation to be absorbed by
Earth’s surface —> keeping earth surface cool

NIGHT:
> absorbs more heat that is radiated from Earth’s surface, preventing it from escaping into space and
thus temperature is higher during night time

Eg. Singapore
Day - 30 degrees
Night - 27 degrees

Rainfall
Relative humidity:

As temperature increases, relative humidity decreases as warmer air is able to hold more water vapour
As temperature decreases, relative humidity increases as cooler air is able to hold less water vapour

Temperature and humidity have a inverse relationship

Formula:

Actual amt of water vapour in the air

————————————————
Max amt of water vapour air can hold
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Convectional and Relief Rainfall
Convectional Rainfall:

Formation:
> Warm air rises as the ground is heated
> As the air rises, it cools to dew point temperature and condenses to form cumulonimbus clouds
> When the clouds are saturated, rain falls

Locations:
> Hot tropical climate and has great amount of sunlight (near the equator)

Features of Convectional Rainfall:

> Occurs in the late afternoon
> Very heavy rainfall with thunder and lightning in a short duration

Relief rainfall:

Formation:
> Moist air from the sea forced to rise over mountain on windward side
> Rising air cools and condenses to form clouds
> When the clouds are saturated, rain will fall on the windward side

Locations:
> near the sea and has high mountains

Features:
> Little to no rainfall on the leeward side as clouds loses their moisture after crossing the mountains
> May cause deserts to form on the leeward side
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Wind
Higher temperature, lower pressure
Lower temperature, higher pressure

Higher altitude, lower air pressure

Lower altitude, higher air pressure

WIND ROSE DIAGRAM

Prevailing wind — direction of which wind blows the most

*If day is NIL, do not draw a square for it, put in the middle of
the hexagon

Eg. 5 NILS — write 5 in the hexagon

Land breeze - night time

• Land loses heat faster than the sea and cooler air over land cools and sinks, higher pressure over
land
• Sea loses heats slower than the land and warmer air from the sea rises and creates lower pressure
over sea
• Blows from the land to sea, decreasing coastal temperature

Sea breeze - day time

• Land heats up faster than sea
• Warm air expands and rises, creating lower pressure over land
• Sea heats up slower, air above sea has lower temperature and high pressure created
• Wind blows from the sea to land
• Lower temperature along coast
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Coriolis Effect
- Deflection of wind generated by rotation of the earth which alters wind direction
- Wind deflects to the right in northern hemisphere
- Wind deflects to the left in the southern hemisphere

Southwest Monsoon (June to September)

- Countries in Southern Hemisphere experience winter with high pressure area.
- Countries in Northern Hemisphere experience summer with low pressure area.
- Southeast monsoon winds blow from high pressure over southern hemisphere to low pressure area
over northern hemisphere.
- When the wind crosses the equators, it is deflected due to Coriolis effect and blow as Southwest
monsoon winds
=> heavy rain to India and Bangladesh as it picks up moisture from Indian Ocean

Northeast Monsoon (December to February)

- Countries in Northern Hemisphere experience winter with high pressure area.
- Countries in Southern Hemisphere experience summer with low pressure area.
- Northwest winds blow from area of high pressure over northern hemisphere to low pressure over
southern hemisphere.
- When the wind crosses the equator, it is deflected due to the Coriolis effect and blows as the
northeast monsoon winds
=> heavy rain to Malaysia as it picks up moisture from South China Sea

3 Types of Climates
Equatorial Climate:

Places that experience this climate:

- Latitude 10 degree north and 10 degree south
- Places near the equator
Seasons and Temperature
- Hot and wet, no snowfall
- High temperature and constant throughout the
year, evenly distributed throughout the year
- Concentration of sun rays over smaller area
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Annual Temperature Range, Mean Annual temperature and Relative Humidity
- Small range
- High temperature
- High relative Humidity
- Annual Rainfall and the type of rainfall
- High rainfall (more than 2000 mm)
- Convectional rainfall and is distributed evenly throughout the year

Monsoon climate:

Places that experience this climate:

- Latitude 5 degree to 25 degree north and vice versa
- India, Bangladesh and Thailand
Seasons and Temperature:
- Wet and dry
- High temperature evenly distributed throughout the year
due to the concentration of sun rays over smaller area
(places closer to the equator)
Annual Rainfall:
- high annual rainfall, unevenly distributed throughout the
year
- Heavy rainfall due to the southwest monsoon winds

Cool Temperate Climate:

Places that experience this climate:

- Latitude 40 degree north to 60 degree north
- Canada, Russia and UK
Seasons and Temperature:
- longer winter and shorter summer seasons
- Low temperature, unevenly distributed throughout the
year, due to sun rays being spread over larger area

Rainfall:
- Evenly distributed throughout the year
- Snowfall due to different seasons
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Answering Structure for Description of Climate:

EQUATORIAL CLIMATE

To describe the climate:

1. Calculate the total rainfall which is evenly distributed throughout the year
2. Average Annual temperature that is high throughout the year
3. Find the annual temperature range

To explain the climate:

Experiences high temperature due to concentration of sun rays over a smaller area. There is high
rainfall due to convectional rainfall and some months have heavier rainfall btw some months due to
northeast monsoon which picks up moisture from south china sea

MONSOON CLIMATE

To describe the climate:

1. Total annual rainfall unevenly distributed throughout the year
2. Average annual temperature that is high throughout the year
3. Find the annual temperature range
To explain the climate:
High temperature due to concentration of sun rays over smaller area. There is heavy rainfall btw some
months due to southwest monsoon which picks up moisture from the Indian Ocean OR Northeast
monsoon which picks up moisture form South China Sea

COOL TEMPERATE CLIMATE

To describe the climate:

1. Total annual precipitation evenly distributed throughout the year
2. Average annual temperature
3. Annual temperature range
4. Maximum and Minimum (state) temperature

To explain the climate:

Low temperature in winter and high temperature in summer and experiences low precipitation
(Further from equator —> solar radiation is spread over larger area —> lesser sun rays absorbed by
atmosphere)
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Global Climate Change
Natural Causes of Global Climate Change

Solar output:
- Changes in magnetic fields —> diff solar radiation emission
- Sunspots —> cooler regions on surface and can be seen dark spots
- Intense solar activity —> no of sunspots increase and cause higher solar radiation —> areas around
sunspots have higher energy to compensate for low tempt

Volcanic Eruption
- Large amt of carbon dioxide, water vapour, sulphur dioxide, dust and ash produced
- Sulphur Dioxide and Water —> Sulphur-Based Particles —> mixed with ash and dust —> reflected
back into space causing global dimming
- Long term effect —> lowering temperature (sunlight blocked)
Eg. Mount Pinatubo in Philippines in 1991 -> Released 17 million tonnes of sulphur dioxide
Lowered tempt of countries in Northern Hemisphere by 0.6 degree celsius for 2 yrs

Greenhouse Effect
- Earth receives shortwave radiation (most absorbed by surface, some reflected back)
- Emitted back into space as longwave radiation —> Absorbed by Greenhouse gases
- Eg of Greenhouse Gases —> water vapour, Carbon dioxide, Nitrous oxide
Enhanced Greenhouse Effect
- Increase in concentration of greenhouse gases —> Human activities such as deforestation,
agriculture, urbanisation, burning of fossil fuels
- Causing Global Warming

Human Factors
Deforestation Burning Of Fossil Fuels Agriculture Industries Urbanisation
Deforestation: (Cleared for land and release of carbon dioxide as a result)
- Define: Loss of forests due to removal of trees in forested area
- Cleared for timber (Wood for furniture and paper)
- Mining for minerals
- Create Land for grazing animals and growing for crops (Agriculture)
- Construction of Infrastructure —> road, building, railways
Eg. Amazon forest in Brazil, Kalimantan Forest in Indonesia, Congo Forest

More carbon dioxide in atmosphere

—> fewer trees to absorb carbon dioxide for photosynthesis
—> More soil exposed through deforestation—> Increase rate of Carbon Dioxide released from soil

Eg. Btw 2000 and 2010, 52000 square km of forest lost due to cattle ranching, soy bean production,
commercial logging and mining

Solutions to deforestation
- Countries started on afforestation programme —> Means trees are planted, imposed laws to limit
trees to be cut ( eg. USA, China and India )
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Burning of Fossil Fuels
- Fossil fuels formed from dead organic matter decomposing over long periods of time
- Demand for land use for housing, farming and industries increases as population increases
- More burning of fossil fuels —> More greenhouse gases

Eg. Oil, Coal and Natural Gases

- Burning of fossil fuels also increases carbon dioxide emissions
- Used for industries, transport and domestic
Eg. 30.6 million tonnes of carbon dioxide emitted from burning of oil, followed by coal and
natural gases
Large consumers —> China, USA, Canada, UK

Agriculture
- Cultivating land, producing crops and raising livestock
- Wet rice cultivation —> greenhouse gases
- Tractors use fossil fuels in order to run which releases CO2
- Inorganic fertiliser releases nitrous oxide in the soil
- Dead leaves and manure release methane (decomposition)
- Cattle ranching increases methane as animals undergo biological processes (eg in Argentina
and Brazil Farms)

Industries
- Production of goods and services within country
- Economic activities such as manufacturing activities/factories —> burning of fossil fuels —>
greenhouse gas

Eg.
- 275 kg of Carbon dioxide released from factory manufacturing computers

- Largest carbon dioxide emissions from industries in USA, Europe and Asia such as China
and India

Urbanisation
- Process where increasing no of ppl who live in urban areas (cities and towns)
- Heating, cooking, cooling and lighting, more vehicles —> more greenhouse gases
- Eg. Tokyo, New York, Beijing, Mumbai, Jakarta
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Impacts of Climate Change
Sea Levels rising
- increase in mean height of sea surface btw high and low tide
Higher Tempt:
- melting of ice caps in Argentina and Greenland —> rise in sea levels (higher risk of flooding)
- Low lying cities and countries submerged
- Eg. Bangladesh and Singapore
More Extreme Weather events
- Heat waves, cold waves, floods and typhoons are more frequent —> land and sea tempt
rising —> High economic losses and deaths (results)

Spread of Infectious Diseases

- Higher tempt and rainfall —> Spread of diseases such as malaria and dengue fever (higher
infection rates)
- Eg. Nepal and Bhutan (tempt rising) —> more dengue fever cases
Lengthen the growing season

Positive impact
- higher temperatures —> longer growing season (more crops can be grown)
- Increase in temperatures in temperate places such as UK allows more fruits to be grown
there
Negative Impact
- some crops that need lower temperatures might not be able to grown
- Eg. Apples and cherries in Yunan China unable to grow due to high temperatures
- Extinction of some animal and plant species (population of Adelle and Emperor penguins in
Antarctica decrease)
- Affects well being and health of people
International Agreements
Kyoto protocol
- UNFCC ( United Nations Framework Convention On Climate Change ) —> Reduce levels of
greenhouse gases
- 16 Feb 2005 where 190 countries signed —> reduce greenhouse emission by at least 5%
than 1990 levels by 2012
- Developed countries to assist less developed countries to reduce emission with funding
SUCCESS: FIG
- Finland, Greece and Ireland installed energy efficient infrastructure (Solar panels and wind
turbines)
- Helped less developed countries
UNSUCCESSFUL: SAD AND ICU
- Countries that signed but did not reduce their emissions by 5% -> Sweden, Denmark and
Austria
- Countries that did not sign but contributed large amounts to greenhouse gases
-> China, USA and India
- Overall global emission increased by 35% in 1997
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National Responses (Strategies that Singapore adopted)
Singapore Green Plan 2012
- Using natural gas as opposed to fossil fuels
- Ministry of Environment 2002, aims for 60% of energy generated by natural gases
- Clean form of energy as natural gases do not release smoke
SUCCESS:

79% Electricity produced using natural gases by 2010

LIMITATIONS:

Underground pipes are expensive to maintain and constant checks required for any leakage

Green Mark Scheme

- BCA (Building Construction Authority) in 2005 —> serves as a award for energy efficient
buildings
- Aims for buildings to be more green and use more energy efficient infrastructure/resources
and environmentally friendly
- Use less energy
Eg of success. JEM and Star Vista —> energy savings of 35% —> Motion Sensor escalators,
recycled water, recycling bins

LIMITATION:
Some companies not supportive as energy efficient and green materials are expensive

Plant a Tree Programme

- Aims to maintain SG status as Garden City by planting trees
- Started in 1971
SUCCESSFUL:
- 70000 trees planted yearly by National Parks Board (NParks)
- Trees are green lungs of the environment as they remove carbon dioxide from atmosphere
LIMITATION:
- Trees take many years to grow (25 years to fully mature and grow to reach full height)
Individual Level
- 3Rs —> Reduce, Reuse and Recycle such as Plastic, Paper
- Use more Public Transport — MRT and buses to minimise petroleum energy
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Typhoons
Formation of cyclone
- Warm moist air rises from warm oceans forming area of low pressure at ocean surface
- Air cools and condenses —> form cumulonimbus clouds
- Strong winds spiral upwards, inwards (at high speeds) at eye wall —> Air rises faster, drawing more
warm air off ocean and sucking cooler and drier air downwards —> forming central area of low
pressure(eye)
- As cyclone moves over oceans —> it picks up more warm and moist air
- Cyclones slow down upon reaching land as it loses energy
Eye wall - intense convection activity with the
heaviest rainfall and greatest wind speed

Eye - area in the centre of cyclone with calm

weather and no clouds

Characteristics of Tropical Cyclones

- Develop at least 8 to 16 degree north and south but not near the equator —> requires the Coriolis
effect to rotate the winds
- Weak Coriolis effect near equator
- Eg. Indian, Pacific, Atlantic Ocean —> Tempt more than 26.5 degrees celcius
- Northern Hemisphere —> Anti clockwise
- Southern Hemisphere —> Clockwise

Hazards:
Storm surges
- Caused by low air pressure and strong winds —> sudden rise in sea levels beyond normal
conditions of high tide
- Low pressure in eye cases sea levels to rise —> pushes waters towards the coast (huge
waves) —> storm surge
- Damage to coastal areas: Properties destroyed by flooding, injuries and death
Eg. Hurricane Ike USA 2008 : US$24.9 billion damage, storm surge of 5m

Strong winds
Causes loose debris to fly and damage property, infrastructure, kill/injure people at coastal
areas
- Impact is larger compared to storm surge
Eg. Hurricane Maria of Category 5 in Puerto Rico —> 3000 deaths and US$90 Billion worth of
damage
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Torrential Rain
- Extreme Rainfall will cause flooding
- Water bodies will receive more water and overflow due to torrential rainfall (flooding)
- Landslides will occur as heavy rainfall causes soil on slopes to become unstable and cause
damage to property (buildings destroyed)

Eg. Hurricane Harvey USA 2003 —> 65 deaths and US$125 Billion worth of damage

Impacts:
Physical Impacts
- Damage caused to houses, buildings, bridges and roads
- Destruction of Transport Networks and Communication Networks damaged
—> Difficult to transport medicine, food, clean water to the locals efficiently and quickly

Eg. Typhoon Jebi Japan 2018 —> 17 Deaths and damage to buildings and tourist attractions

Social Impacts
- Disruption of water supply and sanitation facilities
- Water pipes and pumps damaged
- Sewage pipes are destroyed due to the flooding and sewage will contaminate the clean
water supply —> Water-borne Diseases (Typhoid Fever and Cholera)
- Insects-Borne Diseases such as Dengue Fever due to flooding
- people are forced to move to temporary emergency shelters (homeless)
- Injuries due to debris or killed from damaged property
Eg. Hurricane Katrina in USA 2005 —> caused thousands of people to become homeless and
move to temporary emergency shelters

Economic Impacts
- High Costs to repair damaged buildings and roads
- Loss of income for workers as office buildings and factories are closed
- Loss of income for farmers as farms are damaged —> Less food
eg. Tropical Cyclone Yasi Australia in 2011 ——> damages worth of US$350 million from
croplands being destroyed in farmlands

Responses:
Emergency action:
- Immediate action taken to situations that could pose a danger to the lives of people
—> Government will issue weather warnings and advisories to residents to make preparations
to protect lives and properties

- Evacuations taken place —> move residents to cyclone proof shelters (community cyclone
centre) —> built with strong concrete and raised above ground to withstand the impact of
cyclone (strong winds/storm surges/torrential rainfall) —> located near the home of residents
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- Assistance from neighbouring countries to help repair the damage caused and provide help to
survivors

- NGOs such as the Red Cross send relief teams and volunteers to supply affected areas with
food, clean water, medicine, shelter and clothing

Eg. Typhoon Megi Philippines in 2010 —> 11,190 families had medicine, food, blankets and
mosquito nets from the Red Cross (NGO)

Measures taken to Reduce Impact of Typhoon

Prediction and warning
- Analysing long term climate records and the frequency and severity of the damage caused by
previous cyclones and predict when the next cyclones occurs
However —> only a prediction and is not accurate details of future cyclones
- Computer modelling used to predict the path of cyclones and affected areas and damage
caused
- However, it is only a prediction as the path of cyclone depends on weather conditions
- Predictions can warn residents to prepare for potential cyclones

- Installation of Cyclone warning system to warn residents to evacuate quickly

Land use control

- regulates the use of the land by placing restriction on how the land can be used in the form
of coastal or floodplain management

Coastal Plain Management:

- Areas that is vulnerable to storm surges and flooding —> lesser housing to no housing ,
recreational use advised
- Higher taxes for coastal areas —> avoid higher prices
- Protected zones —> Restrict ALL development —> Used as a barrier against storm surges
and flooding
- Success to some extent - time and management for residents to adhere to the restrictions
- Reluctant residents to move from danger zones as they have been living there a a long time

Flood Plain Management —> plan to minimise the damage caused by floods

- Flood plain —> low lying area near river and coast

- Plan —> mapping land use of area and placing measures to prevent flooding by ensuring new
developments of floodplains are NOT prone to flood
—> Drawing up of evacuation plans to inform residents where to evacuate quickly
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Reduce Vulnerability of Infrastructure:

Design of buildings resistant to wind and water damage —> placing water and electricity lines
underground

- Roofs —> Galvanised steel to prevent roofs from being blown off during cyclone
—> Water resistant Layer to roofs to prevent leakage during torrential rainfall

- Inspection/Maintaining protection barriers such as river embankments and coastal dikes are
regular due to regular erosion by waves
- River embankments —> wall constructed at side of rivers —> Prevent overflowing
- Coastal Dikes —> Artificial stone walls to prevent flooding

* Examples of Cyclones: (useful for essay questions or named exampled questions)

Hurricane Mangkut
- Philippines, Guam
- Category 5
- 11 days in September 2018
- 285km/h
- US$4 billion of damages
- 134 deaths and trees destroyed
Hurricane Maria
- Taiwan, china
- Category 5
- 10 days, July 2018
- 270 km/h
- US$630 million
- 2 deaths, 8 injured and power outage occurred
Hurricane Harvey
- Texas USA
- Category 4
- 15 days, August 2017
- 215 km/h
- US$130 billion
- 108 deaths and 30000 homeless
Hurricane Debbie
- New Zealand, Australia
- Category 4
- 15 days, March 2017
- 215 km/h
- US$3 billion
- 14 deaths
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