Smith to SA: It’s not that hot here

October 31, 2017

It is a fact that 2011 was not one of the 10 warmest years on record.

But this doesn’t change other facts. It doesn’t mean, for example, that 2016, 2015 and 2014 aren’t the three warmest years on record. They are, according to the National Oceanic and Atmospheric Administration. Just as 2010 and 2013 are the fourth and fifth warmest years on record. Just as 2012 was the ninth warmest year on record.

No one would reasonably point to 2011 and say that somehow this shows the weather hasn’t been warmer and warmer in recent years. But that’s the type of argument U.S. Rep. Lamar Smith, R-San Antonio, is making in his criticism of Express-News reporter Brendan Gibbons’ recent article about the triple-digit weather here. Climate models predict about 60 triple-digit days a year here the second half of the century.

To point this out is to be “alarmist,” Smith wrote in a letter to this newspaper. He noted, for example, “in 2017 there were 15 days of 100-degree weather, the same number of days in 1909 and 1964. Last year San Antonio only had six days of 100-degree weather, a significantly lower number of days than observed in the 1940s and 1950s.”

This is true, but it lacks accuracy because it ignores a broader trend. Some years are warm, and some years are cool. Some decades are warmer than others. Unfortunately, recent decades have been exceptionally warm in San Antonio.

We know, for example, that in the 1910s there were 73 days with triple-digit temps, per National Centers for Environmental Information and Applied Climate Information System. We also know in the 1950s there were 125 days with triple-digit temps. And we know that in the 1970s there were just seven triple-digit days.

And we also know temperatures have surged into unprecedented territory here. In the 1990s, there were 144 triple-digit days in San Antonio. In the 2000s, there were 148 such days. In the 2010s, we’re at 174 triple-digit days (so far).

We’ve never had so many triple-digit days in a decade. Not even close. We’re not sure why Smith insists on telling San Antonio residents this isn’t so. It is hotter here than it has been in recorded history. That might change from one year to the next, and it might be attributable to sprawl and heat island effect, not just climate change, but the recent trend is clear.

In his letter, Smith criticizes the modeling used to predict future extreme heat here. “Historically, there has been a large disparity between future temperature predictions and what has been observed,” he wrote.

Is this accurate? We checked with Texas State Climatologist John Nielsen-Gammon, an atmospheric sciences professor with Texas A&M University.

“It is true that global temperatures over the past decade are generally somewhat lower than climate model projections,” Gammon wrote in an email.

But, he continued, this has been taken into account by researchers and experts. Compared with the 1980-1999 period, models predicted an increase of 0.7 degrees Celsius by 2017. The increase was roughly 0.5 degrees Celsius.

“I would characterize this as a small discrepancy rather than a large discrepancy,” he wrote.

But decades, even centuries, are short periods of time. If we zoom out further, we can see the rise in heat coincides precisely with an extreme rise in carbon dioxide emissions. Over the past 400,000 years, carbon dioxide levels fluctuated up and down, but since 1950 they have been at unprecedented and soaring levels.

This is according to NASA’s climate change website under the heading, “Climate change evidence: How do we know?”

“The current warming trend is of particular significance because most of it is extremely likely (greater than 95 percent probability) to be the result of human activity since the mid-20th century and proceeding at a rate that is unprecedented over decades to millennia,” the article says.

What this means, among many dynamics, are warmer oceans and depleted ice sheets, sea level rise and extreme weather. In San Antonio, this means more triple-digit weather. Maybe not every year, as Smith points out. But the trend is definitely alarming.

The lesson here is that scientists are working diligently to provide accurate information about our warming planet and the implications. But it’s easy to pick and choose bits of that information, and bend it to a preferred argument. Perhaps we should be alarmed. In any case, why is it “alarmist” to let science inform policy?