Meteorologist Debunks CNN’s ‘Mann-Made’ Claims About Climate-Driven Heat Waves

In the article “Heat waves are getting more dangerous with climate change — and we may still be underestimating them,” CNN boldly claims that human-induced climate change is making heat waves “more common, intense and longer-lasting,” and that we are likely underestimating the risk. [emphasis, links added]

This is false, refuted by actual long-term temperature records.

The available evidence suggests that while urban areas do experience warmer nights due to the well-documented Urban Heat Island (UHI) effect, there is no global trend of increasing heat wave frequency or intensity after accounting for urbanization, data quality, and the selective reporting that plagues much of the mainstream climate narrative.

CNN does briefly acknowledge that overnight temperatures are increasing in towns and cities, pointing to the UHI effect as a culprit. However, they conveniently skip over the larger implication: these localized temperature increases are not evidence of a trend attributable to climate change.

They are a function of sprawling urban development, including asphalt, concrete, and waste heat from human activity, rather than a signal of global warming, much less a planetary crisis.

Studies show that rural temperature stations, far from the heat-retaining concrete jungles, do not show the same rate of warming as urban stations.

Climate at a Glance: U.S. Heatwaves presents historical data from the National Oceanic and Atmospheric Administration (NOAA), which shows that heat waves were far more severe in the 1930s than they are today.

The number of days exceeding 95°F in the 1930s far surpasses anything seen in recent decades, as shown in Figure 1 below.

Both the intensity and frequency of heat waves were much worse nearly a century ago. CNN chooses to ignore this broader historical context.

In addition, multiple articles on Climate Realism demonstrate that the mainstream media loves to focus on short-term spikes and isolated events while completely disregarding the cooling trends and the full historical record.

One article, “CNN Ignores Long-Term Data, Claims Heat Waves Are Becoming More Severe,” shows how CNN conveniently glosses over the U.S. Environmental Protection Agency’s data, which contradicts their claims, by showing that heat waves were far more prevalent and severe during the 1930s and the 1950s, for example.

CNN’s article leans heavily on attribution studies, particularly those from the World Weather Attribution (WWA) project, which claim that today’s heat waves are made “tens to hundreds of times more likely” by climate change.

These studies are based on climate model simulations, not observed temperature data or trends. The issue with attribution models, as thoroughly discussed at Watts Up With That, is that they often start with the assumption that most warming is due to human activity and then “discover” that warming in their results.

It’s a classic case of confirmation bias wrapped in scientific jargon. In logic, this is referred to as a logical fallacy, in particular, affirming the consequent.

Climate Realism has repeatedly debunked previous attribution “studies” produced by WWA in the past here, here, and here, for example.

To support its assertions about worsening heat waves, CNN sought out the opinions from noted long-time promoters of climate alarm, Friederike Otto and Michael Mann.

Otto, director of the WWA, told CNN that “every heat wave that is occurring today is hotter than it would have been without human-induced climate change.”

What else would Otto say? After all, she runs the organization that’s making the extraordinary heat-wave claims, claims not supported by real-world data.

Her sweeping statement is not grounded in hard, observational data but rather in models that have a known tendency to run hot, consistently projecting more warming than actually observed.

The fact that these models can’t even accurately predict regional temperatures or temperature trends, much less individual heat waves, is conveniently omitted from CNN’s coverage.

Mann warned CNN that “climate models are likely understating the relationship between climate change and persistent summer weather extremes today and under predicting the potential for future increases in such extremes.”

So for Mann, flawed models that project more warming than is occurring are understating heat wave occurrences and severity. Yet increasing trends of either can’t be found in the data.

If anything, the observed evidence suggests that the impact of human greenhouse gas emissions on heat waves is overstated by the climate models WWA uses, not understated.

Even the sensationalized claims about European heat waves fall apart under scrutiny. As pointed out by Climate Realism, these events are well within the range of natural variability.

When past temperature records are carefully reviewed, we find that similar or even more extreme heat events occurred long before industrial CO2 emissions began to rise substantially.

Moreover, CNN recycles the tired trope that heat waves are becoming more “deadly.” Yet, global data consistently show that climate and temperature-related deaths have plummeted over the last century, even as the population has quadrupled.

Bjorn Lomborg has repeatedly illustrated, using data from the International Disaster Database, that deaths from weather-related events—including heat—are down by over 95% since the 1920s, thanks largely to better infrastructure, forecasting, and adaptation. See Figure 2.

CNN often relies on “rapid attribution studies,” as it does almost exclusively in this piece, yet such studies are not real studies in the traditional sense, nor are they peer-reviewed in the traditional sense.

Attribution studies are rushed out rapidly in the hours or days following an event, to push the narrative that climate change is responsible for a particular incident.

They are not careful analyses, examining whether climate change played a role in the event. The latter type of study takes time and detailed research, not the click of a button on a computer, with the built-in assumption that climate change contributed to an event, with the only question being how much.

Attribution “science” is not science at all as it is currently constituted; rather, it is a tool designed to reinforce a narrative, not to objectively investigate the cause of weather events.

Recent heat events pale in comparison to the extended heat waves experienced during the “Dust Bowl” decade of the 1930s and extended heat waves in the 1950s. The cherry-picked comparisons CNN uses actively distort the public’s understanding of climate and weather history.

This isn’t the first time CNN has played fast and loose with climate data. They’ve been called out before, including on Watts Up With That, for exactly this type of fear-driven reporting that ignores long-term records in favor of flashy headlines.

CNN’s persistent misrepresentation of climate data suggests that accuracy is less important to them than sensationalism. Perhaps that’s because fear sells, but it certainly doesn’t inform.

Ultimately, CNN’s reporting here is a disservice to public understanding. Their reliance on shaky models, their neglect of historical context, and their failure to address the well-known Urban Heat Island effect all point to an agenda-driven narrative rather than serious journalism.

If CNN truly cared about informing its audience, it would have corrected these errors by now. Instead, they keep peddling the same fearmongering stories, perhaps because admitting otherwise would undercut the very crisis they’ve worked so hard to sell.

Read more at Climate Realism