LDS Flashcards
What’s is the large data set
Contains the weather data
For 5 UK weather stations
And 3 overseas weather stations
When is data held for
May-October 1987
May-October 2015
What are the UK weather stations
Cambourne Heathrow Hurn Leeming Leuchars
Overseas weather stations
Beijing
Jacksonville
Perth
How many variables does the data set hold information for
11
What are the 11 variables
Daily maximum temperature Daily maximum relative humidity Daily maximum gust Daily maximum wind direction Daily maximum gust direction Daily total rainfall Daily total sunshine Daily mean wind speed Cloud cover Visibility Pressure
na or n/a
Data not available
Daily maximum temperature
Degrees Celsius
1.d.p
Negative means below 0 Degrees Celsius
Which of the 11 variables are given for overseas weather stations
Daily maximum temperature
Daily total rainfall
Daily mean wind speed
Pressure
Daily total rainfall
mm
If total amount < 0.05mm then its referred to as a trace of rain
What is a trace of rain
less than 0.05mm total rainfall collected
Daily total sunshine
Given in hours
1.d.p
Daily maximum relative humidity
How close air is to being saturated with water vapour
Percentages
Relative humidity above 95% associated with mist and fog
Mist and fog associated with
Relative humidity above 95%
Daily mean wind speed
Knots
Categorised according to the Beaufort scale
An empirical and discrete scale
1 knot in mph
1.15mph
What is the Beaufort scale
An empirical and discrete scale
Daily maximum gust
Daily maximum instantaneous speed that occurred over a period of 24 hours
Daily maximum wind direction
Two data processes used to obtain this
In degrees relative to the true north
Corresponding cardinal direction is given
Daily maximum gust direction
Direction wind was blowing in the hour the corresponding daily maximum gust occurred
In degrees relative to the true north
Corresponding cardinal direction also given
Cloud cover
Discrete variable in the data set Measurement of the fraction of the celestial dome covered by cloud Measured in eights Technical unit is oktas 0 oktas is a completely clear sky 8 oktas is completely overcast
Visibility
Measured horizontally
In metres
Dash indicates unavailable data
Pressure
In hectopascals (hPa) Previous unit was the millibar (mb) 1 bar = 100 millibars =100 hectopascals
Cardinal direction
Non numerical scale
Qualititive
tr
Trace of rain
Less than 0.05mm
Issue with daily total sunshine, mean wind speed, maximum gust
Lots of gaps in days where no data recorded
Probability for cloud cover
1/9 if uniform
0 to 8 means 9 categories
Perth key fact
Only one in the southern hemisphere
What can’t you use a normal approximation for
Daily total rainfall; non-uniform/symetrical
SEE MATHS CAP
Cardinal direction
N
E
S
W
NE
NW
SE
SW
etc
How is Perth different for weather
Has its winter between July and September
2 big things about 1987
Great storm in October UK, 15th to 16th and 100knot gusts
Hurricane floyd in October (affects Jacksonville) 1st to 2nd
Something to note about 2015
Hurricane Joaquin in October (affects Jacksonville)
End of spring
May
Summer
June to september
Winter start/autumn
October
Coldest UK Station
Leuchars (most northerly)
Wettest weather station
Cambourne
Driest weather station UK
Heathrow
