Geography of Texas Chapter 2, Continued

Water Resources We know that resources are natural materials that can be used by people. Texas, like other areas, faces challenges such as little rainfall, drought, and the need to meet water needs for its growing population. Texas’ water resources Gulf of Mexico Rivers—Sabine, Neches, Brazos, Colorado, Guadalupe, Nueces, Red, and Rio Grande Thousands of streams Lakes and Reservoirs Aquifers

Texas Rivers Rivers are one of the most important types of water resources in Texas. There are over 11,200 streams in Texas that stretch over 80,000 miles!

Lakes and Reservoirs There are about 200 major lakes in Texas. All but one were formed as a result of human changes to the landscape Reservoirs—human-made lakes were created by building dams in the rivers.

Aquifers Aquifers—a layer of rock or gravel that absorbs rainfall and keeps it flowing underground Aquifers are an important water resource in Texas, but they have been negatively impacted by human use as they are often pumped out to supply water to cities.

Aquifers Ogalla Aquifer—The largest in the state and stretches from West Texas and New Mexico to South Dakota Edwards Aquifer—Stretches through seven Texas Counties and serves Central Texas including Comal County and SVMS

Texas Climate Texas’ climate is diverse and can change quickly Climate is affected by several factors Location Wind Patterns Closeness to the Gulf of Mexico Rainfall

Location and Climate The relative location of Texas has significant effects on its climate. The Gulf of Mexico has a major impact on the climate with it’s gulf breezes that cool the lands in the summer and warm in the winter. Absolute location is a contributing factor to weather also. Texas likes in mid-latitudes, or about midway between the Equator and the North Pole. Since Texas isn’t very far north of the Equator, we have mild winters.

Elevation and Climate Elevation also affects climate. In general, for each 1,000 feet rise in elevation, the temperature cools by 3 degrees. As elevation decreases, temperature increases. Because El Paso is about 3,700 feet, it makes the temperatures cooler than in other areas that are the same latitude. Elevation also affects rainfall. Warm air holds more moisture than cool air. The Davis Mountains of West Texas can receive more rainfall than the neighboring Chihuahuan Desert 24 miles away because the air cools as it rises, holding less moisture.

Texas’ Climate Region Characteristics Cause/Reason All Regions Hot Summers Lots of Sunshine Closeness of TX to Equator Rainfall Increase West to East Warm, moist Gulf air in East TX Rio Grande Valley; North Central TX Hotter Temperatures Warm, dry winds from the West

Texas’ Climate - Continued Region Characteristics Cause/Reason Gulf Coast Cooler Summers, Warmer Winters, Higher Humidity Sea Breezes off the Gulf of Mexico (TX Air Conditioner) Panhandle Colder in Winter, Has Northers Icy Cold Winds sweep down from Canada West Texas Cooler at higher elevation year round At higher elevations air is thinner and absorbs less heat

Extreme Weather Texas also gets its share of extreme weather

Extreme Weather Type Where It Occurs Effects on Life and TX’s Economy Droughts Mainly West Texas Hurts crops, plants, wildlife and places heavy demands and limits on aquifer use Floods Along rivers, especially in the Hill Country Hurts people, crops, plants, wildlife and damages homes, businesses and industries Tornadoes Mainly North-Central Texas (Panhandle—Tornado Alley)

Extreme Weather Type Where It Occurs Effects on Life and TX’s Economy Hurricanes Along the Gulf Coast Hurts people, crops, plants, wildlife and damages homes, businesses and industries Blizzards Panhandle and North Texas

Label on your map (triangles) Find and label these rivers and waterways: Sabine Red Rio Grande Brazos Gulf of Mexico

Label on your map Find and label these aquifers: Ogalla Aquifer Edwards Aquifer

Label on your map Find and label these plains: Great Plains Gulf Coast Plains

Label on your map Find and label these areas: Hill Country Balcones Escarpment Guadalupe Peak

Label on your map (dots) El Paso Dallas Fort Worth Houston San Antonio Austin Amarillo Galveston