The High Plains region is heating up.

“In recent years, the Texas High Plains, as well as many other locations across the U.S. and the world, recorded average temperatures rising almost every year and at an increasing rate,” says B. A. Stewart, USDA-ARS (retired), Amarillo.

“Of the last 34 years, only two have recorded below normal temperature,” says Stewart, who adds that his observations are not politically based but supported by hard data compiled by the National Oceanic and Atmospheric Administration (NOAA).

NOAA has recorded climate data since 1895, Stewart says. The first normal values were calculated in 1930 based on 1901-1930 measurements. “The data also indicate that unless significant cooling occurs soon the temperature normal for the 2030 decade will be even higher,” Stewart says.

Attention grabber

“What got my attention,” he adds, “is a NOAA temperature graph that shows a big hump in the 1930s and another significant increase in the 1950s and ‘60s. But the normal now is higher than the moving average in the 50s and 60s. Temperatures began to increase during the 1980s and have increased dramatically since 1990.”

The trend is concerning, Stewart says.

“As bad as the past high temperatures were, they pale in comparison to today. Since 1990, only 1993 and 1997 had annual temperatures below normal.”

Challenging for agriculture

Stewart says a continuation of the rising temperature trend poses significant challenges for agriculture.

“Crop production cannot be maintained if temperatures continue upward. In recent years, agriculture production in the Texas High Plains has become increasingly challenging. The Ogallala Aquifer has been seriously depleted, and dryland yields have been decreasing. While low and highly variable rainfall is always a factor, the number one concern now is the rapid rise in temperatures.”

 Stewart has spent a long career watching the climate.

“After spending my entire life and career in the Southern Great Plains and the last 55 in the Texas High Plains, I remain deeply interested in the climate,” he says.

Born in 1932, Stewart says he remembers only the later stages of the Dust Bowl. “What I remember most was the pain and stress  I saw in my Daddy and Mother as they struggled to keep a small dairy operating in Southwest Oklahoma.”

He remembers the 1950s better. “I was starting my career as a joint employee of Oklahoma State University and USDA Agricultural Research Service as a member of the department of agronomy at Stillwater.”

Dirty Thirties

He refers to the Dust Bowl era as the “Dirty Thirties” and the 1950s as “The Filthy Fifties.”

Both eras featured rising temperatures and devastating losses to agriculture and economic viability.

“The length of the Filthy Fifties was not as long as the Dirty Thirties, and the economic losses were not as bad because of more government assistance than during the Dirty Thirties, which coincided with the worst economic depression ever experienced by the U.S.,” Stewart says.

He says his concern is for “the tremendous challenge that agriculture producers are likely to face in the future and how that will affect the agriculture economy of the region.”

Rising temperatures

He refers to data from NOAA’s Climate at a Glance, available at (https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/).

The first normal value was 57.9 degrees for 1930, which increased to 58.3 for 1940. The big jump was due to high temperatures during the Dirty Thirties, Stewart explains.  It remained fairly close for 1950 but took another jump for 1960 because the 30 years in that calculation included the high temperatures of both the Dirty Thirties and the Filthy Fifties.

“Normal temperatures began to decline slightly as the abnormal values from the Dirty Thirties or the Filthy Fifties were no longer included,” Stewart says. “However, normal temperatures began to increase significantly with the 2000 normal.

“The present normal temperature value is 59.6. To put this into perspective, for the entire 128 years of record, only 27 exceeded today’s normal. During the Dirty Thirties, nine years were above normal but only three exceeded today’s normal. Also, during the Filthy Fifties, five years were above normal but only two were above today’s normal. 

Higher normal

“The normal average annual temperature for the Texas High Plains today is 59.6 degrees Fahrenheit. That is the average annual temperatures for 1991-2020. That value will be the normal until 2031 when it will be replaced by the average of 2001-2030 temperature values.”

Stewart says precipitation values have not changed much but are more variable. “Since 1990, 22 years were below normal precipitation compared to 12 above.”

Warmer temperatures and decreasing capacity to irrigate will mean declining crop production, Stewart says.

“A degree or two can cause major changes in cropping systems as we know by comparing agricultural systems from the southern to northern parts of the Texas High Plains,” Stewart says. “Lubbock has an average annual temperature about 2.5 degrees higher than Amarillo, and the cropping systems are different. Since 1930, the average annual temperatures have increased 2 degrees, and 1.2 of those have occurred since 1990.”

Crop effects

He says the combination of higher temperatures and a declining aquifer will mean lower  productivity. “Corn will disappear from the High Plains. Cotton will move north; it already has. High Plains producers will move more acres to irrigated and dryland cotton.

“Wheat production will decrease,” he adds. “Some farmers will change to forage. These changes will not happen next year, but in the future agriculture around Lubbock could look more like San Angelo or Lamesa as crop production decreases.”

The trend extends north. “South Dakota is now a Cornbelt state,” Stewart says

“Wheat yields are going down in Texas, are down a little in Oklahoma, remain about the same in Kansas, and are increasing in Nebraska. Wheat yields have increased significantly in South Dakota, and North Dakota is now growing winter wheat, all because of temperatures increasing South to North.”

He adds that the Texas situation is exacerbated because of limited water resources. 

Climate focus

Stewart says climate was a focus during his 64-year career with OSU and USDA-ARS. “I started my career at OSU in the 1950s, a devastating climatic era that was drier than the ‘30s but did not last as long. I’ve been fascinated with climate ever since.”

In addition to field and administrative work at USDA, Stewart also served as director of the research center at Bushland, Texas.

“I retired from USDA and went to West Texas A&M University and stayed there for 25 years.”

Stewart has studied climate across the United States and numerous foreign countries.

He concludes in a recent report that without an abatement of rising temperatures, crop options in the Texas High Plains will change.

“The assumption was that weather for the next 10 years would be somewhat similar to the average of the past 30 years, with some years higher and some lower than normal. It was also assumed that the deviation from normal would not be rapid from decade to decade but would show gradual changes.

“In recent years, temperatures in the Texas High Plains, as well as many other locations in the U.S. and world, have been rising almost every year and at an increasing rate.

Water factor

“Higher temperatures increase water demand,” Stewart says, “so dryland farming is becoming more challenging every year, and a high percentage of the irrigated land in the region is already woefully short of water and becoming more so each year.

“Producers will need to make changes in crops and cultural practices. However, without some slowing or decrease in rising temperatures, many areas within the Texas High Plains will reach a tipping point where farming is no longer sustainable.”

Stewart is not overly pessimistic.

“Food production will shift,” he says. “We will adapt. We have no choice.”