CHAPTER 11

WEATHER AND

CLIMATE

Let’s think about SingaporeLet’s think about Singapore

Weather Is All Around Us

Meteorologists are people who study the atmosphere

Weather is the condition of the atmosphere at a particular place over a short period of time

Climate refers to the weather pattern of a place over a long period of time, usually 30 years or more

The basic elements of weather and climate: Temperature Rainfall Wind

Temperature Temperature refers to the degree of hotness or

coldness of the air It varies throughout the day in a place The temperature rises and falls as the Earth rotates

from west to east (seasons) Places nearer the Equator are warmer throughout

the year than places farther away

Temperature

The temperature rises during the day and falls at night

It also varies from place to place

Temperature gets cooler as we go to higher grounds

AltitudeAltitude

Refers to the height of the landRefers to the height of the land Warm air rises – this air cools as it rises and Warm air rises – this air cools as it rises and

thus temperature decreases as we increase thus temperature decreases as we increase with heightwith height

Thus, temperature decreases with Thus, temperature decreases with increasing heightincreasing height

LatitudeLatitude Places near the earth’s Equator (e.g.: Singapore, Places near the earth’s Equator (e.g.: Singapore,

Malaysia) receive a higher concentration of Sun’s Malaysia) receive a higher concentration of Sun’s rays and thus more sunshinerays and thus more sunshine

Places further away from the Equator (North Places further away from the Equator (North pole, South pole) receive a lower concentration of pole, South pole) receive a lower concentration of sunshine as the sun’s rays are spread over a sunshine as the sun’s rays are spread over a larger area. larger area.

Thus that is why places further away from the Thus that is why places further away from the equator are cooler.equator are cooler.

Measuring Temperature Air temperature is measured with

a thermometer The scale is in degree Celsius (ºC) Daily maximum temperature

refers to the highest temperature reading for the day

Daily minimum temperature refers to the lowest temperature reading for the day

Glass tube

Mercury or alcohol

Calculating Temperatures

• The mean daily temperature is the average temperature of a place on any one day

FormulaMean daily

temperature =

Daily maximum Daily minimum temperature + temperature

2

Calculating Temperatures

• The daily temperature range is the difference between the maximum and minimum temperatures recorded in a day

FormulaDaily temperature range

=

Daily maximum Daily minimum temperature - temperature

Calculating Temperatures

• The mean monthly temperature is the average temperature of a place in a month

FormulaMean monthly

temperature =

Sum of mean daily temperatures for the month

Number of days in the month

Calculating Temperatures

• The mean annual temperature is the average temperature in a place within a year

Formula

Mean annual temperature =

Sum of mean monthly temperatures in the year

12

Calculating Temperatures

• The annual temperature range is the difference between the maximum and minimum mean monthly temperatures recorded in a year

FormulaAnnual temperature range

=

Maximum Minimum mean monthly - mean monthly temperature temperature