large data set

where are the 5 weather stations in the UK located

camborne

heathrow

hurn

leeming

leuchars

where is camborne located

most south in cornwall

where is hurn located

south west england (dorset)

where is heathrow located

south east of england in greater london

where is leeming located

north yorkshire

where is leuchars located

most north in scotland

what is specific about camborne and leuchars

they are both coastal so are windier

• beijing

• jacksonville

• perth

when was the weather data measured

May-October

in 1987 and 2015

what changed in October of 87

great storm in south/south east of england

high wind speeds and rainfall

what should you remember about october

colder

windier

wetter

darker

what is the typical range for daily mean temperature

5 - 24 degrees celcius

how is total rainfall measured

in mm

• tr/trace means less than 0.05mm

what is specific about trace data

needs to be in numbers

what is the typical range for daily total rainfall

0 - 20 mm

how is total sunshine measured

to the nearest 0.1 of an hour

what is the typical range for daily total sunshine

0 - 14 hours

how is mean windspeed measured

• kn/knot (nautical mile per hour)

  • 1kn = 1.15mph

• Beaufort scale

  • 0 = Calm (less than 1 kn)

  • 1-3 = Light (1-10 kn)

  • 4 = Moderate (11-16 kn)

  • 5 = Fresh (17-21 kn)

what is the typical range for windpeed

3 to 10 kn

light to moderate

what is maximum gust

highest instantaneous wind speed

• in kn

what is the typical range for daily maximum gust

8 to 50 kn

how is mean wind direction measured

mean direction of wind is calculated each hour → daily mean wind direction

recorded in LDS as modal wind direction of these hours

given in degrees relative to true north to the nearest 10

where the wind is coming from

how is maximum gust direction measured

direction wind was blowing in the hour the corresponding daily maximum gust occurred

given in degrees relative to true north to the nearest 10

cardinal direction

what is the typical range for wind/gust direction

10 to 360 degrees

what is mean visibility

how many decametres can be seen into the horizon during daylight hours

what is a decametre

10 metres

what is the typical range for daily mean visibility

200 to 4000 dm

what is humidity

percentage of air saturation with water vapour

100% is the max

what is the typical range for humidity

70 - 100%

what does a humidity of above 95% mean

mist or fog

what is mean pressure measured in

hectopascals (hPa)

what is the typical range for daily mean pressure

990 to 1040 hPa

how is mean cloud cover measured

• eighths of the sky covered by cloud

oktas

what is unique about cloud cover

the only discrete variable

what is the range for daily cloud cover

0 to 8

is the data complete

• missing/unknown data listed as n/a or -

• data should be cleaned before samples taken

how do you clean data

replace tr with either 0 or 0.025

where are the three international weather stations located

jacksonville

beijing

perth

what is specific about jacksonville

hot summers

what is specific about beijing

hotter and wetter summers

colder winters

what is specific about perth

flipped seasons