The Heatwave

This part of the UK was relatively warmer last week than any of my Ten Weather Stations. (Relative, that is, to the 2009 to 2018 average, and by extension to my version of a Pre-Industrial baseline.)

39_FullTable

With the arrival of meteorological Autumn in the northern hemisphere I’ve changed the main chart in the weekly look at one of the Ten Stations (and Durham Tees). Rather than considering the last ten weeks, I’m offering the running average of the Mean Daily Temperature above Pre-Industrial from January to the latest completed month, with a Trendline to the end of the Met Year. I’m noting the end-of-year temperature expected from the trend and wonder how much different the actual figure will be, for each of the stations, the hemispheres and the globe (as represented by the Ten).

(I have deliberately excluded December from this series because at several stations the Met Year began with some extreme temperatures, which made trend forecasts appear unrealisable. I don’t put any “faith” in the forecasts themselves but I’m hoping the actual figures in the next three months might indicate either continuing warming or solar minimum cooling setting in. I still haven’t found a reliable canary.)

wks30to39_Rome

Remember, my weeks run from Saturday to Friday, so it was Monday in Rome that was relatively chilly. The actual high that day was 84ºF, 28.9ºC and the Mean 75ºF, 23.9ºC. The Met Year running Mean was 0.96ºC colder than the Ten-Year running average for that day, hence the 0.11ºC below Pre-Industrial figure.

Dorian is the Monster of the Week, right now up to a Cat 5 and battering the Bahamas. Models are showing a turn to the north tomorrow and Tuesday, perhaps reprieving Florida. The Carolinas could bear the brunt but there seems to be a possibility of the hurricane losing strength as it heads north-east over the sea. Fingers crossed.

Robin Westenra has posted that New Zealand is expected to have a cold start to its spring. I trust my Wellington Airport temperatures will reflect the forecast – if it proves to be correct.

Northern Winter

It was 56 years ago, or thereabouts when a “new” maths teacher sat with me for some one-to-one tuition. After a few minutes, he told me what I already knew – I had no facility with figures. Mr Gibbins inspired me, though; I knuckled down. I’m sure he would have been amused had he known I got a job in a government department of statistics.

Anyway, the provisional temperature figures from my Ten Weather Stations are in. I don’t think, dear reader, that you will appreciate it if I throw too many at you, all at once. They tell a load of stories but  I’ll try to follow a moderation in all things strategy.

My original intention was to see if I could get an early warning of the onset of the promised Grand Solar Minimum – or of the sudden increase in temperature because of a threatened release of Arctic methane (from melting permafrost). The first three months of the current meteorological year don’t seem to point in either direction, definitively.

Yesterday, my YouTube recommendations included this video from Veritasium. It is quite short and, I thought, an excellent introduction to the uncertainties of Climate Change/Global Warming. I hope you will watch it.

Very briefly, I have copied the daily AVERAGE temperatures for Ten Weather Stations for the ten meteorological years from December 2008 to November 2018. For simplicity, I give each year the “name” of the 11-month year, viz 2009 to 2018, rather than 2008/9 to 2017/18 Averaging ten years of AVERAGE temperatures gave a ten-year baseline which enabled me to determine where warming has brought us since the start of the Industrial Age.

The Intergovernmental Panel on Climate Change and other organizations tell us that temperatures have risen n degrees since “Pre-Industrial” (or some more recent baseline of their devising). I have decided it is pointless agonising over which baseline and which temperature rise to choose.

I’ve settled for a rise of 0.85°C since 1710. I mentioned in an earlier post that I thought this was “conservative” and heard someone offer a one degree C rise since 1850 a few days ago. Really, any reasonable “ballpark” figure will do, as long is it is rigorously applied to all the weather stations in the project.

I have calculated the pre-industrial baseline figure for each day of the year for the ten stations and for this first quarter of the meteorological year deducted the actual daily AVERAGE temperatures reported to Weather Underground.

Given the nature of the 2009 to 2018 baseline, one would expect temperatures for any day in 2019 to have a 50% chance (roughly) of being warmer. And, given the variability of our weather, the difference could be many degrees warmer (or colder). Averaging the AVERAGE daily temperatures for a whole month and comparing the result with the average for the 10-year baseline will reduce the difference – but it still might be more extreme than you’d expect. Averaging the three months of the Northern Winter and Southern Summer will reduce the monthly differences further.

And, thinking ahead, averaging the AVERAGE daily temperatures for the whole meteorological year will yield an annual figure that can be set against a statement such as, “The average global temperature has increased by 0.85°C since the beginning of the Industrial Revolution”.

So, how have my 5 northern stations fared this winter compared to the 0.85°C above Pre-Industrial of 2009 to 2018?

NorthWinterAboveP-I

A note on the colour coding in the first column.

BLUE: below the Pre-Industrial Baseline!

GREEN: between 0 to 1.49°C above Pre-Industrial.

ORANGE: above the Paris Accord but below 2°C.

RED: 2°C and more above Pre-Industrial.

The amount of warming and cooling this quarter is indicated in the second column.

Novosibirsk is the coldest of the five locations but, given the brutality of the Polar Vortex in North America, the Washington DC result is more surprising. As I said, these figures are provisional. I’ll check!