Geography
Reading Climographs
Differences between weather and climate
Factors of Temperature
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Altitude
Latitude
Maritime and continental effect
Distance from the sea
Cloud cover
Wind and ocean current
Aspect
Length of day
Agriculture
Inputs
Process
Outputs
Human factors:
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Labour
Transport
Market and Distance
Government (political)
Capital (finance)
Technology
Physical factors:
 Relief
 Climate
 Soil
GM food
 HYVs
 Implications/consequences
 Pros/cons
Reading Climographs
Diurnal range of temp: diff between max and min temp in a day
Formula: max temp-min temp = diurnal range
Annual range of temp: diff between mean monthly temps of the warmest
month and coolest month of the year
Formula: max monthly temp - min monthly temp
Average/ Mean temperatures/rainfall
Total/total annual/mean annual temperature/rainfall
Example of a climograph:
It’s foolproof.
Distribution of temp: Uniform/ Seasonal
Mean annual temperature: Low/ High
Annual temperature range: Small/ large
Annual precipitation distribution: Seasonal/ Distributed
Temperature/
Precipitation
Mean annual
temperature
Total annual
precipitation
High
Moderate
Low
>20
10 to 20
<10
>1000
250 to 1000
<250
Model answer:
Singapore’s temperature is constant, with a high mean annual temperature of about 27
Celsius. The annual temperature range is small, about 2 Celsius. There is rainfall throughout
the year and it is quite evenly distributed. Total rainfall is high, more than 2000mm at 2275 min.
Comparing weather conditions by climographs:
The two weather stations have similar mean annual temperatures but the range is much
smaller in Station A than B, and this could be because Station A is at a coastal area, and the
sea absorbs and loses heat quickly, thus narrowing the range of temperature.
Diffs between weather and climate
Weather: State of atmosphere at a place over a short period of time
Climate: Average atmospheric conditions over a wide area over a long
period of time (at least 30 years)
Factors of temperature
Altitude
Height of a point above sea level
Normal Lapse Rate: Falls by 6.5 Celsius with every 1000m increase
Heat is absorbed by the Earth surface and heats the air above it through
conduction
Higher altitude air is less dense than air at sea level and has a smaller
concentration of gas to trap heat
Latitude
Distance (in degrees) to the North and South of the equator
Increases as we move further from the Equator
Higher latitude:
Sun’s rays strike at an angle
Solar radiation spread over a larger area
Heat is more distributed and the area is cooler
Sun rays travel further to reach the area
A large proportion of the rays are absorbed or reflected by the ozone layer
Sun rays reaching areas at higher latitude are less intense
Lower latitude:
Sun’s rays strike perpendicularly
Solar radiation concentrated on a smaller area
Heat is more intense and the area is hotter
Sun’s rays travel a shorter distance to reach the area
Smaller proportion of the rays are absorbed or reflected by the ozone layer
Rays that reach the area are less intense
Maritime and Continental Effect
Heating and cooling of the sea and land
Maritime effect:
During hot periods of time, the air over land gains heat faster than the sea
The cooler air over the sea lowers the temperature of the coastal areas
During cool periods of time, the air over land loses heat faster than the sea
The warmer air over the sea raises the temperature of the coastal areas
Coastal areas thus experience a smaller range of temperature
Continental effect:
Land far from the sea is not influenced by the temperature of the sea
Inland areas thus experience a larger range of temperature
Cloud cover
Amount of clouds over an area
Lack of clouds:
Large amounts of solar radiation reach the Earth’s surface in the morning
Temperature of the ground rises quickly
Large amounts of heat escape from the Earth’s surface into outer space at
night
Thus areas with less cloud cover experience less difference in day and night
temperatures
Presence of clouds:
Cloud cover reflects part of the incoming solar radiation during the day
Less solar radiation is absorbed by the Earth surface
Heat escaping from the Earth surface at night is reflected back by the clouds
Cloud covers keep the temperature of the ground relatively high at night
Thus areas with more cloud cover experience more difference in day and
night temperatures
Winds and ocean currents
Onshore winds blowing across warm ocean currents raise the temperature of
coastal lands
And vice versa 
Aspect
Northern Hemisphere
South-facing slopes receive direct solar energy and are protected from polar
cold winds
Sun’s rays reach these slopes at steeper angles and the heat is distributed
over a smaller area
Southern Hemisphere: vice versa.
Tropical latitudes: Angle of the midday sun is high and effect of aspect is less
noticeable
Length of Day
Days decrease from summer to winter areas.