weather & to measure rainfall
DESCRIPTION
This document explains about rainfall measurement techniquesTRANSCRIPT
Energy & Environment
Why should we record the weather?Climate & Weather affects:
So we know what to plant where and when
Crops Livestock
Jobs & Lives
If we record weather we can predict from trends....
Why should we record the weather?We also need this information to design structures
Rainwater harvesting tank
Solar cells
Wind turbine
Dam
The weather can have disastrous effects!
Drought
The weather can have disastrous effects!
Flood
How we record the weather-Weather Instruments
Measures air temperature
Measures air pressure
Measures amount of rain over a given time
Shows direction wind coming from
Measures wind speed
Anemometer
Barometer
Wind Vane
Thermometer
Rain Gauge
Where would you put a weather station?
Concrete Grass
Under trees or buildingsShelter from sun and rain from trees and buildings
Heat radiation from concrete
Vigyan Ashram’s Weather Station
Could this be improved?
?
Make your own weather instruments
Rain Gauge Anemometer
Split into three teams
Wind Vane
Team 1:Make your own rain gaugeAvailable Resources:
Rain Gauge
Resources are limited so design before you construct!
A straight Plastic Bottle
Scissors/Knife
A ruler
A marker pen
Sticky tape
string
Bamboo stake
Team 2:Make your own anemometer
Anemometer
Available Resources:
Resources are limited so design before you construct!
Cardboard
2x small straight sticks/bits of bamboo
A nail
A ruler
A big bit of bamboo
sellotape
scissors
Team 3:Make your own wind vane
A short piece of bamboo
A nail
AcrylicAvailable Resources:
Wind Vane
A ruler
Available Resources:
Resources are limited so design before you construct!
How do your designs compare to these?
Wind ActivityMeasure the length from the centre of the anemometer to the cardboard cups
Circumference= π x DiameterWhere π=3.14
This is the radius of the circle that is created when the wind blows.
The diameter of the circle=2 x radius
Now find the circumference of the circle
Wind ActivityCount the number of revolutions per minute(It will help if you mark one cup so you can identify one spin)
Multiply this by the circumference. This will give you the speed of the wind in m/min
Convert this to Km/Hour to see what the wind is classed as today
Wind Speed (Km/hour)
Term Description
0-5 Calm Smoke goes straight up
6-20 Light Wind is felt in face, leavesmove
21-39 Moderate Flags flap, dust is raised
40-61 Strong Large branches move
62 or more Gale/Whole Gale
Use the wind vane to find out what direction the wind is coming from
Wind ActivityX revs/min
X revs/min x Circumference=speed of wind (m/min)
Speed of wind (m/min) / 1000=speed of wind (km/min)
Speed of wind (km/min) x 60=speed of wind (km/hr)
Rain Gauge RecordingDay Time Today’s Height
of Water (mm)New Rainfall(Today’s height-yesterday’s height)
Observations
Monday 9.30 20 20-18=2 18mm from last Sunday
Tuesday 9.30 22 22-20=2
Wednesday 9.40 22 22-22=0 Sore back so could bend down
Thursday 12.00 26 26-22=4
Friday 9.00 28 28-26=2
Saturday 9.20 30 30-28=2
Sunday 9.30 32 32-30=2
What is important when you read a rain gauge?
Should be at the same time every dayEnsure you are eyelevel to the water surface to get an accurate reading
Can you see a trend in this chart?
Plot this info in a graph
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Monday Tuesday Wednesday Thursday Friday Saturday Sunday
rain
fall
in m
m
Day of the week
Rainfall in Week 1Easy to see trends
Pune Rainfall and Temperature Charts
Summary Questions1. What does an anemometer measure?2. Where is the best place to put a weather station?3. Why is it useful to measure the diameter of an
anemometer?4. What is important when measuring from a rain
gauge?5. What are graphs good for?