Year 9 Microclimates Fieldwork
Purpose of the fieldwork:
1) To investigate microclimatic data at a small scale, within Ashby School grounds.
2) To identify the most suitable location for the school’s weather station.
Technique 1: Wind speed and direction
Equipment
 Wind sock
 Anemometer
 Compass
 Beaufort scale
 Record sheets
Methodology
1.
A compass should be used to determine North.
2.
The wind sock should be placed in the exact location to be investigated, and the variable, for example height above ground kept constant at each site.
3.
The Beaufort scale can be used to give a crude, qualitative judgement of wind speed by observing evidence around the site.
4.
An anemometer can give a more accurate reading, and will work in very low wind conditions.
5.
Readings should be recorded at each location.
Considerations: Limitations and validity
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Very high or low wind speeds can be difficult to measure.
Wind strength is hard to measure at ground level.
The Beaufort scale is subjective. You need to consider that the observations are likely to come from around the site, rather than at the exact location. Is it therefore an accurate method for a micro-climate assessment?
Taking several readings and finding the average can increase validity of results.
Technique 2: Temperature and light level
Equipment
 Thermometer
 Light meter
 Record sheet
Methodology
 Use the digital thermometer and light meter to take a minimum of three temperature and light readings
 reading at each site. Use these readings work out the average level at each field work location.
Record the cloud cover at the time of taking measurements as this information can be used to help explain anomalies in data. Cloud cover is estimated in Oktas which refers to how many eighths of the sky are covered by cloud.

Considerations: Limitations and validity
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A sampling method should be decided upon to ascertain the method for data collection, for example the locations to sample, the timings and frequency of recordings
Digital thermometers are reliable and precise but may not be if poorly calibrated or the batteries run low
(always check the batteries).
Some account should be taken of the fact that recordings will inevitably be taken at different times in different locations - while cloud cover can change from one moment to the next, affecting temperature and light readings. Cloud type could also be recorded, as this affects light intensity.
Allow for some margin of error in using the instruments - different products vary in accuracy and performance.
Readings may be affected by direct sunlight, or hand-heat. Ground temperatures are more extreme, so readings should not be taken directly on the ground.
Technique 3: Precipitation (data has already been collected)
Equipment
 Rain gauge
 Record sheets
Methodology
1.
Homemade gauges can be used (ensure the same ones are used to ensure a fair test).
2.
Gauges should be set up in the desired locations.
3.
Records should be kept of anything at each site which may affect readings, for example shelter from buildings or vegetation cover.
4.
Leave gauges for a predetermined period of time at each location (24 hours)
5.
For remote locations, bucket-siphon rain gauges can be used to take measurements which empty themselves daily.
Considerations: Limitations and validity
 Consider the effect of vegetation, interception of rain or buildings providing shelter.
 Evaporation, some open gauges allow evaporation which will affect readings.
 Rain splash, gauges flush with the ground level may be affected by rain splash, therefore over estimating
 precipitation.
Also, extremely heavy rain may cause excess runoff (especially from some surfaces) which may run into flush rain gauges.
 Rain gauges raised above ground level may underestimate precipitation as rain may be funnelled around the gauge.