Global Warming

First chance of a 1.5°C year 2024 0r 2034?

Global monthly temperature anomalies have exceeded 1.5°C above pre-industrial levels nine times or so in individual months in the HadCRUTv5 series since 2016. I’ve adjusted the baseline of the chart above by the LTALTA Long Term Average. This is usually defined as a 30 year period by the WMO. for the 1850-1900 period to calculate the increase in temperature since the start of the pre-industrial age. Some global series don’t extend as far back as 1850, GISTempGISTemp v4 The GISS Surface Temperature Analysis version 4 is an estimate of global surface temperature change using data from NOAA GHCN v4 (land stations) and ERSST v5 (ocean areas). 4 for example, so I imagine they can’t use this value and the LTA must be reduced to 20 years. I’ve added a 3 year linear trend (warming at the rate of +1.094°C/decade) to the chart above, and extrapolated it forward to find when 12 month average global anomalies will reach +1.5°C if temperatures remain at their record levels for the next nine months or so. The 12 month moving average could achieves this by November 2024, until six months ago I wouldn’t have believed this were possible, but with six consecutive record warmth months, I now beleive it’s perfectly possible.
If you take a more measured approach, and use a linear trend over the last 30 years (warming at the rate of +0.213°C/decade), then the 1.5°C won’t be reached for another 10 years, that’s in January 2034. So when will it be? My money’s on 2024, but I could be wrong. 😉

Global Temperatures | November 2023 | Sixth consecutive hottest month

The scores-are-in, and it’s a ten-from-Len, as the world produces a sixth consecutive record warmest month for November, which is a record in it’s own right. I make the daily mean for November 9.81°C which is 0.22°C higher than the previous warmest in 2015. It’s not quite as impressive as in previous months, but nonetheless it’s still quite remarkable. The Daily values from my DIYDIY Do It Yourself series are no less impressive as you can see in the graph below. This year started setting daily records at the beginning of June and it’s been #1 daily warmest for much of the six months since then. Remember you heard it first here even if it was a racing cert 😉

September 2023 – Global Temperatures

For the fourth month in a row global temperatures have set another new monthly record for warmth. September is perhaps the most remarkable of the four in my DIYDIY Do It Yourself global temperatures series, exceeding the previous highest in 2016 by a massive, in global temperature terms that is, of 0.24°C. The question that immediately springs to mind is when will this run of new extremes come to an end? Maybe when it comes full cycle in June of 2024, or who knows if the El NinoEl Niño El Niño 'The Boy' is the warm phase of the El Niño–Southern Oscillation and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific is still running it will just continue.

Currently, on the 30th of September, the daily mean global temperature is in open water on the graph above way higher than in any of the previous daily temperatures since 1948. What’s driving the sharp rise in global temperatures are the higher than average SSTSST Sea Surface Temperatures in the central Pacific Ocean. The La NinaLa Niña La Niña is an oceanic and atmospheric phenomenon that is the colder counterpart of El Niño, as part of the broader El Niño–Southern Oscillation climate pattern. The name La Niña originates from Spanish for "the girl", by analogy to El Niño, meaning "the boy". In the past, it was also called an anti-El Niño[1] and El Viejo, meaning "the old man." event which had been keeping a check on global temperatures until earlier this year has gone, replaced by a strengthening El Nino.

Global temperature +1.5°C prediction

I wrote code to display this graph that extrapolated a 30 year linear trend that predicted when global temperatures would reached the much vaunted value of +1.5°C above pre-industrial levels around 10 years ago now. That prediction of 2035 hasn’t seemed to change too much each time I run the code if my memory serves. I thought that I would post the results to just keep a record of how right or wrong I was. That does presuppose of course that this blog and I will still be around in 2035 of course, and if the month of July is correct, just celebrated my 81st birthday. I would have been much happier in my dotage if global warming and been global cooling but that’s life.

Surge in Iberian temperatures in recent years

It seems to me that even allowing for the rise in temperature due to global warming, there’s been an additional surge in temperatures across Iberia and northwest Africa in recent years. That’s particularly noticeable in summer, but can also be seen in the rest of the year too. The latest plume event is ongoing at the moment (27 April 2023), but has had a limited northward extent so far. I decided to look back at the last 40 years of daily maximum temperatures at Cordoba to see what I could find by plotting a scatter graph and adding a trend line.

As you can see I’m using the 1981-2010 LTALTA Long Term Average. This is usually defined as a 30 year period by the WMO., which is courtesy of Wikipedia, and not the latest, but the linear trend at Cordoba does show a warming trend of well over a degree a decade. I can’t say if these results are just local to Cordoba, or if they’re occurring more widely across the rest of Iberia and Northwest Africa, but it does go a long way to explain the media hype about the present heatwave. I’m sure some more detailed research would find that there’s been an increase in Spanish plumes events in all seasons of the year, and that their effects aren’t just limited to the Iberian peninsula.

April 27, 2023

Global Warming, Heatwave, Spain

Surge in Iberian temperatures in recent years Read More »