As you learn about the regions and distinct climates in Texas, you may recognize how diverse the weather is that extends throughout the state. Similar to changing weather patterns and climates we see throughout other areas in the world, changes are occurring in Texas too. How do those climate changes affect the diverse range of ecosystems distributed across the various landscapes in this great state?
Scientific data clearly show that the Earth is warming. And, of course, Texas is not excluded from that warming. In the majority of the state, temperatures have risen over one-degree Fahrenheit over the last one-hundred years, with the increase attributed to greenhouse gas emissions.1United States Environmental Protection Agency. (2016, August). What Climate Change Means for Texas. United States Environmental Protection Agency. https://www.epa.gov/sites/production/files/2016-09/documents/climate-change-tx.pdf The culprit of anthropogenic warming (human-induced warming) is carbon dioxide (CO2). Carbon dioxide and other greenhouse gases (methane, nitrous oxide, etc.) in the atmosphere capture sunlight that otherwise would be reflected back into space, and reflect the energy back to Earth’s surface, slowly warming our planet. Therefore, the more greenhouse gases in the atmosphere, the greater the amount of heat that is trapped. Even water vapor and clouds act as greenhouse gases.
CO2 Emissions in Texas
The problem of CO2 emissions is exacerbated here in Texas, with the highest emissions nationally due to the state’s energy consumption and resultant greenhouse gas emissions into the atmosphere. Much of these emissions are a result of energy consumption by the industrial sector in Texas (~7,500 trillion BTUs in 2019), which produces goods for not only the nation but the world.2EIA. (2021, April 15). Texas State Profile and Energy Estimates. Energy Information Administration State Energy Data System.https://www.eia.gov/state/?sid=TX#tabs-2
Drought and Water Use
With increased temperatures comes increased evapotranspiration, especially in areas that are prone to arid climates and less available rainfall (North and West Texas).
Over 10% of the state currently relies on irrigation for agricultural purposes, and that percentage is expected to increase greatly. Where does this water come from? Aquifers in the subsurface. The High Plains aquifer (also known as the Ogallala aquifer) underlies parts of eight states, and in Texas, can be found beneath the Texas Panhandle and portions of Far-West Texas. Water-levels began declining in parts of the High Plains aquifer soon after the onset of substantial irrigation using groundwater (about 1950). The aquifer has been depleted by half in less than one-hundred years, as shown in the figure below. Increased temperatures and carbon dioxide mixing with surface-waters are also attributable to sea-level rise, with the potential to have a severe impact on the coast in Texas.3McGuire, V.L. (2017). Water-level and recoverable water in storage changes, High Plains Aquifer, predevelopment to 2015 and 2013–15. U.S. Geological Survey. Scientific Investigations Report 2017–5040. (https://pubs.usgs.gov/sir/2017/5040/sir20175040.pdf
Combating the increasing risk of drought in Texas will be exacerbated with overuse of water resources. To mitigate the issue of both overuse and prolonged drought, Texas will require improved water management solutions and techniques, such as less water usage and discovery of new water resources.
Sea level is rising in Texas. Some causes are global and others are local. Globally, ice is melting from land (e.g., Antarctica and Greenland) and ocean waters are warming, and thus expanding. Locally in Texas, sea level is rising more rapidly than some other coastal areas because as the ocean water is rising, the land is sinking as a result of pumping groundwater and other fluids from the subsurface.
While rainfall will be reduced in some regions of Texas into the future, other areas, such as East Texas, may experience an increase in rainfall, which comes with its own ramifications. Temperatures correlate with rate of precipitation. Higher air temperature from anthropogenic warming results in increased precipitation, because warmer air can hold more water vapor. Increased rainfall can induce higher vulnerability to flooding, which can be financially burdensome and severely impact the landscape/ecosystem. According to the U.S. Environmental Protection Agency, “During the last 50 years, the amount of rain falling during the wettest four days of the year has increased by about 15% in the Great Plains.”4U.S. Environmental Protection Agency. (2016, August). What Climate Change Means for Texas. United States Environmental Protection Agency. https://www.epa.gov/sites/production/files/2016-09/documents/climate-change-tx.pdf Large metropolitan areas such as Houston, are vulnerable to infrastructure damage as a result of increased flooding, such as the devastating flooding that occurred during Hurricane Harvey in 2018.
More Intense Storm Events
Aside from more intense rainfall, climate change will also bring about intensified storm events, such as hurricanes, and tornados. The coast of Texas has historically been at risk for hurricane landfall; however, that problem will be exacerbated with warming sea-surface temperatures in the Gulf of Mexico. Hurricanes that batter the United States Gulf Coast are also susceptible to shifting patterns of the El Niño Southern Oscillation teleconnection, where an eastward trending Pacific Jet Stream brings warmer waters and lower air pressure during the El Niño phase, resulting in greater susceptibility to storms. However, scientists have questioned whether increased sea-surface and atmospheric temperatures have abated these teleconnections. Warmer air temperatures also increase susceptibility of tornadoes, where portions of Texas that reside in Tornado Alley are at risk.
National Guard in Texas employed following the aftermath of 2018 Hurricane Harvey.
Image Credits: Photo Courtesy of the National Aeronautics and Space Administration, U.S.A.; Energy Information Administration; Texas Highway Department Historical Records, Texas Commission on Environmental Quality, Public domain, via Wikimedia Commons; Photo Courtesy of the USGS ; U.S. Army photo by 1st Lt. Zachary West, Public domain, via Wikimedia Commons