Climate Action Now, page-220

Gladly.


(https://www.thegwpf.org/content/uploads/2024/03/History-Weather-Extremes.pdf)

Now, it takes 6 pages before anything scientific is actually referenced. The first 6 pages are referencing news paper articles. This isnt exactly how scientists get their data. This is considered a secondary source and has limited value.

The first actual science article (https://science2017.globalchange.gov/downloads/CSSR_Ch6_Temperature.pdf) is referenced with this graph.

Which does indeed show that the 1920's in the contiguous United States did have more warm spells and more intense heat waves. Unfortunately, the United States isn't the globe, and what happens in the US doesn't necessarily mean that its happening elsewhere. I cant seem to find a similar graph for any other continental region over the same time period (from 1900 - 2000).

I did find scientific articles that showed graphs from a starting point of the 1950's which showed an increased in frequency of heatwaves, but I wont use them

Furthermore, the sourced material in the GWPF (CSSR) has the following statements conveniently ignored by the GWPF 'report'

"Annual average temperature over the contiguous United States has increased by 1.2°F (0.7°C) for the period 1986–2016 relative to 1901–1960 and by 1.8°F (1.0°C) based on a linear regression for the period 1895–2016 (very high confidence). Surface and satellite data are consistent in their depiction of rapid warming since 1979 (high confidence). Paleo-temperature evidence shows that recent decades are the warmest of the past 1,500 years (medium confidence)."
and

"Annual average temperature over the contiguous United States is projected to rise (very high confidence). Increases of about 2.5°F (1.4°C) are projected for the period 2021–2050 relative to 1976–2005 in all RCP scenarios, implying recent record-setting years may be “common” in the next few decades
(high confidence)."

and

"Extreme temperatures in the contiguous United States are projected to increase even more than average temperatures. The temperatures of extremely cold days and extremely warm days are both expected to increase. Cold waves are projected to become less intense while heat waves will become more intense. The number of days below freezing is projected to decline while the number above 90°F will rise. (Very high confidence)"
I'll remind you, this isn't my source, this is the source that the Global Warming Policy Foundation used. In the business, we call this cherry picking - finding a small snippet, quoting it out of context, without telling the whole picture. So yes, whilst heatwaves in the US may have shown a peak in the 1920's, (and it appears to be trending up since the 1960's anyway), this wasn't a global phenomena (at least not according to the report, because they only quoted a couple of newspaper clippings from Australia, (They didn't even mention Europe, Africa, Asia, or South America once again, not showing any data or graphs for Australia or any other region from 1900 onwards.)

Do you know why they didn't mention those regions? I'd certainly like to know, so if you have anything please share.

You can see by this study (https://www.sciencedirect.com/science/article/abs/pii/S0048969716314516) that the total global area affected by heatwaves has increased in the last 30-40 years (you can see the 1920's which show that increased short term variability in the United States, but the total land area affected by heatwaves appears to have doubled and even tripled compared to the pre 1990's) So whilst the raw number of heatwaves may be the same as the early 1920's in the US, the overall scale in size of those heatwaves is increasing.

The article then goes on to talk about floods, and droughts. I am not going to go through every source because I am going to assume the author has made the same logical fallacies and has cherry picked his data. Using newspaper articles is a very limiting way to collect data and doesnt really give you and scientific background.

The phenomena of early twentieth century warming is known to climate scientists. And guess what?

"The ETCW received a lot of prominence from the scientific community even during the period itself (Scherhag, 1939a). Callendar (1938) attributed the warming to atmospheric CO2 rise." (https://wires.onlinelibrary.wiley.com/doi/10.1002/wcc.522)

Remember, CO2 concentration really started to rise around 300 years ago, so to see some extreme weather events responses in the 1920's (200 years of rising CO2) isn't particularly unbelievable.

But I digress, I read the first main topic of the 'report' and used scepticism to point out flaws.

I look forward to your response.