Extreme weather is nothing new to Texans, but data suggests it will become more frequent as we approach our bicentennial in 2036 — and the consequences could be severe.
While actual weather from year to year is largely unpredictable, a review of long-term data over Texas’ past hundred years reveals significant trends that point to an increased risk of destructive natural disasters.
This year will be best remembered for the extreme winter weather in February, and a relatively mild summer is still fresh in our minds.
However, data clearly shows that Texas is getting hotter. This summer would have been regarded as a steamy one if it had happened in the 1970s or 1980s. And this year notwithstanding, trend data show that the number of 100-degree days has more than doubled over the past 40 years and could nearly double again by 2036.
Similarly, while we’ve had a relatively wet year, hotter temperatures point to increased threat and severity of drought. Hot days increase the rate of evaporation from the soil and from water bodies, which means droughts take a harder toll when they strike.
So, if — or when — Texas experiences another dry period such as those in the early or middle 20th century, the higher temperatures will lead to even more severe effects.
While all of Texas is susceptible to the effects of extreme weather, Houston and the Gulf Coast are at particular risk.
The Texas coastline is retreating along nearly the entire length of its barrier islands. In Galveston Bay and probably other bays and estuaries behind the barrier islands, new sediment is not being deposited quickly enough to keep up with relative sea level rise, leading to loss of coastal wetlands.
As the Gulf of Mexico encroaches, the likelihood of catastrophic storm surge from hurricanes increases. Rising sea levels lead directly to increased risk of storm surge.
The places along the coast with the largest rates of relative sea level rise may have a doubled storm surge risk by 2050, even before the effect of stronger hurricanes is factored in.
Houston has experienced a significantly increased risk of flooding from heavy rainfall. Most of the big-city stream flow gauges across Texas that show a clear upward trend in flooding are in Harris County.
In fact, by 2036, the odds of extreme precipitation across the state are expected to have increased 30% to 50%.
Trend data do show that extreme winter cold and storms, such as those Texas experienced in February, are becoming less frequent. The bad news is that even worse winter weather has hit the area in the past and sooner or later probably will do so again — such storms very much remain a threat.
One important lesson from February, and from Hurricane Harvey as well, is that very bad things can happen when the weather strays far outside our past experience — “unprecedented” usually leads to tragic.
By analyzing trend data, we can imagine better what the next unprecedented event might look like in time to do something about it.
Texas’s weather is changing, and it’s doing so in a way that will make it harder to deal with extreme weather events and more expensive to recover from them.
That means preparation and resilience are more important than ever. Texas’ long-term prosperity will depend on how well we prepare for these increasingly damaging natural disasters.
John Nielsen-Gammon is a Regents Professor at Texas A&M and has been Texas State Climatologist since 2000. Holly Heard, who previously worked at the Houston Education Research Consortium at Rice University, is Director of Data and Analytics for Texas 2036.