Introduction to Multilingual Retrieval Augmented Generation (RAG)
Â
Weather elements unit 15
1. Unit 15: Weather Elements
Objectives
Differentiate between weather and climate.
Understand the use and siting of the weather
instruments.
2. Weather
⢠Weather
describes the
condition of the
atmosphere of a
place over a
short period of
time.
⢠Temperature, rai
nfall and wind
Climate
⢠Climate is the
average conditions
of the atmosphere
of a place over a
long period of time.
⢠Average
temperature and
average rainfall
pattern is used.
4. Is this a weather or climate data?
Climatic maps are used to show information
such as distribution of temperature and rainfall
of a country, region or the world.
5. Thermometer
⢠Temperature refers to the degree of heat in
the air. It tells us how hot or cold the air is.
⢠A thermometer is used to measure
temperature in degree Celsius (âŚC) or degree
Fahrenheit(âŚF).
⢠Sixâs Thermometer or the maximum and
minimum thermometer is used to record the
highest and lowest temperatures of a day.
7. ⢠Made up of Mercury and
Alcohol
⢠Mercury â Very high
boiling point
⢠Alcohol â Very low
freezing point
⢠Read off the base of the
Indices (Indicators)
8. Activity - Reading the Sixâs
Max = 30 oC
Min = 5 oC
Mercury
Metal
Indices
Alcohol
Max = 20 oC
Min = 10 oC
Max = 7.5 oC
Min = -15 oC
9. Stevenson Screen
⢠The Sixâs thermometers are placed in a
white, wooden box called a Stevenson Screen.
⢠White wooden box to reflect heat
⢠Louvred sides to allow air to flow freely
⢠Doubled layered roof to prevent direct heating
from the sun
⢠Stand on stilts to prevent heat from the
ground to be trapped
10.
11.
12. Calculating Temperatures (1/5)
Daily temperature Range
= Maximum Temp - Minimum Temp
For example
Max temp = 30 oC Min Temp = 10 oC
Daily temp range = 20 oC
13. Calculating Temperatures (2/5)
Mean (average) daily temperature
= Maximum Temp + Minimum Temp
2
For example
Max temp = 30âŚC Min Temp = 10âŚC
Average daily temp= (30+10)/2
= 20âŚC
15. Calculating Temperatures (3/5)
Mean (average) monthly temperature
= Average max temp + Average min temp
2
Only used this when
average maximum and
average minimum
temperature are given.
18. Location X
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Temp 23 22 20.5 16.5 14 10.5 10 11 12.5 14 17.5 21
Mean Annual Temperature
= Total of mean monthly temperature / 12
= (23 + 22 + 20.5 + 16.5 + 14 + 10.5 + 10 + 11 + 12.5 + 14 + 17.5 + 21 ) / 12
= (192.5) / 12
= 16.04 oC
Annual Temperature Range
= Highest Temperature â Lowest Temperature
= 23 â 10
= 13 oC
19. Location Y
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Temp 25.5 26 26.5 27 27.5 28 27.5 27 26.5 26.5 26 26
Mean Annual Temperature
= Total of mean monthly temperature / 12
= (25.5 + 26 + 26.5 + 27 + 27.5 + 28 + 27.5 + 27 + 26.5 + 26.5 + 26 + 26 ) / 12
= (321) / 12
= 26.75 oC
Annual Temperature Range
= Highest Temperature â Lowest Temperature
= 28 â 25.5
= 2.5 oC
20. ⢠Average daily or mean daily temperature:
⢠Calculation of temperature data:
Temperature
Average daily or
mean daily temperature
Maximum temperature + Minimum temperature
2
=
Daily temperature range Maximum temperature - Minimum temperature=
Average monthly
temperature
Sum of average daily temperatures for the month
Number of days in the month
=
Average annual
temperature
Sum of average monthly temperatures in a year
12
=
⢠Daily temperature range
⢠Average monthly temperature
⢠Average annual temperature
21. â˘An instrument used to measure the amount of
rainfall
â˘Rain falls through a funnel and is collected in the
bottle
â˘Excess rain that overflows is collected in the
copper cylinder
â˘Amount of rain collected is poured into a
measuring cylinder, calibrated in millimeters
⢠Rain gauge:
Rainfall
outer cylinder funnel
glass
bottle
measuring
cylinder
copper
cylinder
22. â˘One-third of
the rain gauge
is sunk into the
ground to
prevent
toppling
â˘To be placed in
an area free of
obstructions
â˘Rain gauge:
Rainfall
copper
cylinder
funnel
glass bottleouter
cylinder
27. ⢠Horizontal movement of air from a high
pressure area to a low pressure area
⢠Associated with land and sea breezes
Wind
wind
high
pressure
low pressure
cold air sinkswarm air rises
land Sea
28. Wind
â˘In the day, air over the sea is cooler than that
over the land, thus the cooler air
sinks, creating a higher pressure area.
â˘Warmer air over the land rises, creating a low
pressure.
â˘Differences in pressure cause the air over the
sea to move towards the low pressure over the
land.
â˘This horizontal movement of air causes wind.
NOTE: Greater differences in pressure give rise
to stronger breezes.
29. â˘The wind vane
points to the
direction where
the wind is
blowing from
â˘It is made up of
a freely moving
pointer and four
cardinal points â
north, south, ea
st, west
⢠Measuring wind direction:
Wind vane
30. â˘The wind rose records the
wind direction.
â˘It is represented by a
centre circle and eight
arms representing the main
eight compass directions.
â˘The number of calm days is
recorded in the centre
circle.
â˘The longer the arms, the
more days the wind is
received from that
direction.
Wind rose
5 E
S
N
NW
SW
NE
number of calm days5
31. ⢠Siting of weather
instruments:
Wind
Stevenson screen
⢠120cm above ground level
⢠Sixâs thermometer is kept inside
⢠insulated from heat by material
and design
rain gauge
⢠30cm above ground level
⢠on short grass away in an open
field from buildings
wind vane
⢠top of the meteorological
station with no obstructions