This is a very provisional quick look at some of the CLIMAT data from UK sites, chosen as probably fairly trustworthy over this time period in the light of the ongoing surface stations project.
I pulled out Tmax and Tmin, fed into the novel analysis software here to see what it makes of it. I’ve let it extrapolate.
The most obvious commonality is the above. It isn’t,large enough to notice to a human, half degree either way.
As expected Tmin is more problematic. I won’t go into the gory details but most of it makes sense in relation to site instabilities.
I expected Lerwick to be a reference so I was dismayed to note it only starts data in 2000. Very little is known about the site.
The inclusion of Lyneham is a hunch, slightly know the place and I suspect it has been fairly consistent without the “little war” panic changes near the met site. (aerodrome is closing end of this year so that dooms the meteorological site)
Manston is problematic but Tmax far less so than Tmin.
Most of remaining stations are active military bases or civil airports. If I do the other stations, needs automating, I have no idea if the above will hold up.
Quick web search, see if this period is known.
To my surprise there is recent work pointing at this period as a precursor to UK weather flows.
“Variability in the Global Equatorial Ocean (1000m) from Argo
Argo data show that 4.5-year Atlantic cycle associated with slowly propagating high-baroclinic mode waves is the dominant variability at depth”
– “Tropical Atlantic Climate Experiment Peter Brandt, IFM-GEOMAR, Kiel, Germany, 10M PDF from clivar.org
– PDF of abstract above EGU2011-4599 – CO Meeting Organizer
I’d be interested to see the phase of what they found.
The origin of 4.5y, I’d expect this to be related to earth plate positions, geometry of ocean and land with the excitation the annual orbit.
That will do for the moment, more if you search.
post by co-moderator