As can happen with blog posts something contentious turns up, it won’t lie down, I was trying to move on to other things. Roger Andrews emailed me about some movement results he has unearthed, which relate to this earlier post on UHI at Heathrow Airport.
No head image here, are too large, read on to see.
Image from report here.
Plot produced by Roger Andrews. Note: right hand scale should be the same as figure 1.
Extracted the movement data and added an overlay plot. Sure hope I have the X axis of the whole thing spot on. The movement data is spot day figures.
So what is going on?
I can understand plotting a mean won’t show anything, including given the poor underlying data resolution. It is part day only.
What does “movement” mean?
100+ tonnes of fuel fully laden or landing empty?
Freight or passenger?
Easter is in there too where we know record traffic was broken and seems to be in the temperature.
A possibility is the heat is from something else. I did mention the close proximity of the passenger terminal vehicle access tunnel, for those who don’t know it is major dual carriageway. Then we have people in buildings, were sleeping there so services were very active.
Doesn’t make sense. Ideas anyone?
[UPDATE 22nd April 2012]
I’ve now created new software which creates a patch plot, done entirely under my control, no guessing or assumptions by third parties. This is a work in progress so where it will go from here remains to be seen.
The above uses dark grey for missing data, lighter grey for zero, the rest is obvious. No scales. A patch is for one hour during one day. Runs 1st April to 30th April, zero hours at the bottom and 23hrs at the top . Movement data as RA, is spot values for each day.
I might now be in a position to unearth detailed runway usage information. There is a pattern of usage with direction and takeoff/land switched to a schedule but there is variance on practice.
Post by Tim Channon, co-mod