Being in the power business for 30-plus years and having a scientific education, I have been watching the climate change discussion for some time. I have long advocated not using climate change as a rationale to support renewable energy policy given the controversy around the climate issue and the ability for renewable energy projects to stand on their own economic merits.  

However, climate change is no longer a discussion about the a priori science, data adequacy, models, Al Gore, etc.

During this decades-long discussion about climate change, the climate didn’t wait for us humans to realize the effect was real: the climate changed all on its own, notwithstanding the lack of universal acceptance of this phenomenon by mankind. 

The observations of the temperature and other data points over the past 175 years, especially those of the last 10 years, are quite conclusive. The claim that CO2 levels will cause the earth to warm is supported by the observed data, and the alternative thesis that we are seeing natural variation has been rejected.

The numbers of global temperatures

Looking at the 174-year modern temperature record, one has to ask the simple question: What is the joint probability that the change in global temperature is due to natural variation vs. long-term climate change? 

The probability of climate change happening as a product of natural variation is 1 in 2.5 x 1017.

The probability of winning the Powerball or MegaMillion is 1 in 300 million (or 3.0x108).

The probability that our temperature observations are natural variation is 1 in 10 million times the probability of winning the national lottery. That is, “almost surely zero” in math speak.

How did I calculate this probability?  

The easy answer is by using simple high school math and Excel. I downloaded global annual temperature anomaly data, calculated this data’s mean, and the difference of each year from the mean, and then calculated each year’s probability in Excel. For example, the probability of occurrence of the global temperature in 2022 was 0.28%, and in 2015 was 4.88%.

Then, once the probability of each year’s occurrence was calculated, I took the joint probability of each of the past ten years having occurred, that is, asking the question: What is the probability that we would observe each of the years one after the other? It's not hard, takes under ten minutes, and is easily replicable by any high school student in statistics class.

In 2007, we crossed the P10 mark, that is, the year in which it was only 10% likely. By 2015, we crossed the P5 threshold, the year in which it was only 5% likely. It gets worse. By 2021, we hit P01, and now, in 2023, it is only 0.2% likely. The probability of observing these global temperatures year after year due to natural variation is “almost surely zero”.

Given this almost surely zero outcome, the claim that we are seeing just natural changes in the weather and not climate whose temperatures are undergoing an external forcing is rejected – the claim is simply not supported by observations.

Back to the actual scientists, Zachariah 2023 looked specifically at July 2023 in the US West and concluded: “Climate change made these events several orders of magnitude more likely in North America and Europe. We can thus conclude that without climate change these events would have been virtually impossible to occur.”

Figure 2. 2023 Western US temperature anomaly

Climate skepticism

Skepticism toward scientific theories, even those that reached the threshold of being “widely accepted” is very much a part of the scientific process. Scientists can be arrogant, the media presents “facts” through political perspectives (and that goes both ways certainly), and politicians do lie and frankly may not even remotely care.

However, the claim that all the qualified scientists, the 97%+ majority are somehow all in collusion with each other is not supported by looking at the process of scientific consensus on other issues from quantum mechanics to black holes.

Just to be clear, the following American scientific organizations all support the climate change thesis: the US National Academy of Sciences, the US Global Change Research Program, the American Association for the Advancement of Science, the American Chemical Society, the American Geophysical Union, American Medical Association, American Meteorological Society, American Physical Society, The Geological Society of America, etc.

Natural systems can be very difficult to model as they are very complex multi-fractal, chaotic phenomena. Physical phenomena such as temperature, wind, and rain forecasts are likely to have far more volatility and “fatter tails” than that which is normally predicted by models used to forecast uncertainty. Skepticism is very much an important element of the scientific process. I would also note, that there is plenty of excellent misinformation on this important subject, and this misinformation has gotten pretty good over the years.

The climate issue has historically not been so straightforward to understand or articulate. The climate discussion has historically been one about science, models, and math. It is only in the past ten or fifteen years that objective climate observations have clarified this issue. Most of us with scientific backgrounds have understood the issue for decades and consensus on this issue was reached over fifteen years ago in the scientific community. Nevertheless, the skeptics should be appreciated, and their concerns answered. It is important that public opinion catch up with both scientific consensus and the physical conditions we are all observing.

Back to the 97% of climate scientists, we no longer have to believe all those NASA and NOAA-educated PhDs, all those tenured university professors who had studied the climate for decades at the best schools in the word, or all the peer-reviewed published research, the endorsements of the National Academy of Sciences and virtually every other global scientific organization, the climate didn’t wait for public opinion, it changed all on its own due to the physical conditions and not detoured by public opinion. And that change is undeniable.

Conclusion

Just know this, the probability the climate is not changing due to man-made forcing is 1 in 2.5 x 1017.  Ask yourself, “Where is the error in the probability math?”, seems like that is the only relevant factor anymore. 

We already know yesterday’s weather – and it's hotter now, and it's hotter because of us. Climate change is already causing harm to humans and to our global economy, and this harm will get worse even if we want to deny the underlying science. Furthermore, making the world more efficient and modernizing our energy economy is a good thing, not a bad thing.