4% rOil United States
1"P'flfcA Environmental Protection
August 2016
EPA 430-F-16-045
What Climate Change
Means for TexaS

Texas's climate is changing. Most of the state has
warmed between one-half and one degree (F) in the
past century. In the eastern two-thirds of the state,
average annual rainfall is increasing, yet the soil
is becoming drier. Rainstorms are becoming more
intense, and floods are becoming more severe. Along
much of the coast, the sea is rising almost two inches
per decade. In the coming decades, storms are likely
to become more severe, deserts may expand, and
summers are likely to become increasingly hot and dry,
creating problems for agriculture and possibly human
Our climate is changing because the earth is warming.
People have increased the amount of carbon dioxide
in the air by 40 percent since the late 1700s. Other
heat-trapping greenhouse gases are also increasing.
These gases have warmed the surface and lower
atmosphere of our planet about one degree during
the last 50 years. Evaporation increases as the
atmosphere warms, which increases humidity, average
rainfall, and the frequency of heavy rainstorms in many
places—but contributes to drought in others.
Greenhouse gases are also changing the world's
oceans and ice cover. Carbon dioxide reacts with water
to form carbonic acid, so the oceans are becoming
more acidic. The surface of the ocean has warmed
about one degree during the last 80 years. Warming is
causing snow to melt earlier in spring, and mountain
glaciers are retreating. Even the great ice sheets on
Greenland and Antarctica are shrinking. Thus the sea
is rising at an increasing rate.
Temperature change (°F):
-1 -0 5 0 0.5 1 1.5 2 2.5
Rising temperatures in the last century. The western part of Texas
has warmed twice as much as the eastern part. Source: EPA, Climate
Change Indicators in the United States.
Rising Seas and Retreating Shores
Sea level is rising more rapidly along the Texas coast than the rise caused by
climate change alone, because the land is sinking, largely because of ground
water pumping. If the oceans and atmosphere continue to warm, sea level is
likely to rise two to five feet in the next century along much of the Texas coast.
Rising sea level submerges wetlands and dry land, erodes beaches, and
exacerbates coastal flooding. Many types of birds and fish depend on tidal
wetlands. Shore erosion can eliminate public access along the beach,
especially where development is immediately inland.
Coastal Storms, Homes, and infrastructure
Tropical storms and hurricanes have
become more intense during the past
20 years. Although warming oceans provide
these storms with more potential energy,
scientists are not sure whether the recent
intensification reflects a long-term trend.
Nevertheless, hurricane wind speeds and
rainfall rates are likely to increase as the
climate continues to warm.
An eroded beach on North Padre
Island impairs public access along
the shore. © James G. Titus; used
by permission.
Whether or not storms become more intense,
coastal homes and infrastructure will flood
more often as sea level rises, because storm
surges will become higher as well. The rising sea is likely to increase flood
insurance rates, while more frequent storms could increase the deductible for
wind damage in homeowner insurance policies. Many cities, roads, railways,
ports, airports, and oil and gas facilities along the Gulf Coast are vulnerable
to the combined impacts of storms and sea level rise. People may move from
vulnerable coastal communities and stress the infrastructure of the communi-
ties that receive them.
Rainstorms and Tornadoes
Changing the climate is also likely to increase inland flooding. During the
last 50 years, the amount of rain falling during the wettest four days of the
year has increased about 15 percent in the Great Plains. Over the next
several decades, the amount of rainfall during the wettest days of the year is
likely to continue to increase, which would increase flooding.
Scientists do not know how the frequency and severity of tornadoes will
change. Rising concentrations of greenhouse gases tend to increase
humidity, and thus, atmospheric instability, which would encourage
tornadoes. But wind shear is likely to decrease, which would discourage
tornadoes. Research is ongoing to learn whether tornadoes will be more or
less frequent in the future.

Water Resources
Despite the increase in heavy storms, changing climate is likely to
make water less available overall. As warmer temperatures increase
evaporation and water use by plants, soils are likely to continue to
become drier. Average rainfall is likely to decrease during winter,
spring, and summer. Seventy years from now, the longest period
without rain each year is likely to be at least three days longer than
it is today. Increased evaporation and decreased rainfall are both
likely to reduce the average flow of rivers and streams.
Drier soils will increase the need for farmers to irrigate their crops,
but sufficient water might not be available. Approximately
14 percent of the farmland in Texas is irrigated; in the Panhandle
and the plains to the south, most irrigation water is ground water
from the High Plains Aquifer System. As a result, this aquifer is
becoming depleted. Since the 1950s, the amount of water stored in
the aquifer has declined by more than 50 percent in some parts of
the state.
Wildfires and Landscape Change
Higher temperatures and drought are likely to increase the severity,
frequency, and extent of wildfires, which could harm property, live-
lihoods, and human health. On average, more than 1 percent of the
land in Texas has burned each decade since 1984. Wildfire smoke
pollutes the air and can increase medical visits for respiratory and
heart problems.
The combination of more fires and drier conditions may expand
deserts and otherwise change parts of the Texas landscape. Many
plants and animals living in arid lands are already near the limits
of what they can tolerate. A warmer and drier climate would
generally extend the Chihuahuan desert to higher elevations and
expand its geographic range. In some cases, native vegetation
may persist and delay or prevent expansion of the desert. In other
cases, fires or livestock grazing may accelerate the conversion of
grassland to desert in response to the changing climate. For
similar reasons, some forests may change to desert or grassland.
The 2011 drought contributed to widespread wildfires in Texas, like this one
behind the McDonald Observatory near Fort Davis. Credit: Frank Cianciolo,
McDonald Observatory.
Percent depletion of ground water in the High Plains Aquifer, 1950-2013.
Source: USGS.
Increasing droughts and higher temperatures are likely to interfere
with Texas's farms and cattle ranches. Hot weather causes cows
to eat less, grow more slowly, and produce less milk, and it can
threaten their health. Reduced water availability would create
challenges for ranchers, as well as farmers who irrigate crops.
Yields would decline by about 50 percent in fields that can no longer
be irrigated.
Hot Weather, Air Pollution, and Human Health
Hot days can be unhealthy—even dangerous. Seventy years from
now, Texas is likely to have three or four times as many days per
year above 100°F as it has today. Certain people are especially
vulnerable, including children, the elderly, the sick, and the poor.
High air temperatures can cause heat stroke and dehydration and
affect people's cardiovascular and nervous systems.
Warmer air can also increase the formation of ground-level ozone,
a key component of smog. Ozone has a variety of health effects,
aggravates lung diseases such as asthma, and increases the risk
of premature death from heart or lung disease. EPA and the Texas
Commission on Environmental Quality have been working to
reduce ozone concentrations. As the climate changes, continued
progress toward clean air will be more difficult.
Declines	No substantial change ;|«| Area where the aquifer
More than 50%	10% to-10%	stores little or no water
25% to 50%
10% to 25% Rises	— County boundary
¦ 10% to 25%
More than 25%
The sources of information about climate and the impacts of climate change in this publication are: the national climate assessments by the U.S. Global Change Research
Program, synthesis and assessment products by the U.S. Climate Change Science Program, assessment reports by the Intergovernmental Panel on Climate Change, and EPA's
Climate Change Indicators in the United States. Mention of a particular season, location, species, or any other aspect of an impact does not imply anything about the likelihood or
importance of aspects that are not mentioned. For more information about climate change science, impacts, responses, and what you can do, visit EPA's Climate Change website
at www.epa.aov/climatechanae.