1. F LOODS I N T EXAS Causes of floods in Texas! Largest and 4 th largest city in US state. Largest metropolitan in the state

2. T EXAS AND ITS CLIMATE. Texas is also called the Lone Star State and it’s the second largest U.S state in both area and population. Other major cities include San Antonio, El Paso, and Austin—the state capital. Texas contains diverse landscapes, resembling in places both the Deep South and the desert Southwest. Traveling from east to west, one can observe piney woods and semi-forests of oak and cross timbers, rolling plains and prairie, and finally the desert of the Big Bend. The large size of Texas and its location at the intersection of multiple climate zones gives the state very variable weather. Texas has many precipitation patterns. El Paso, on the western end of the state, averages as little as 200 mm of annual rainfall while Houston, on the southeast Texas averages as much as 54 inches (1,400 mm) per year. Dallas in the North Central region averages a more moderate 940 mm per year. Generally, snow falls multiple times each winter in the Panhandle and mountainous areas of West Texas, once or twice a year in North Texas, once every few years in Central and East Texas, but snow rarely falls south of San Antonio or on the coast except in extreme circumstances.

3. T EXAS C LIMATE ( CONTINUED ) Thunderstorms strike Texas often, especially the eastern and northern portion of the state. Tornado Alley covers the northern section of Texas. The state experiences the most tornadoes in the Union, an average of 139 per year. These strikes most frequently in North Texas and the Panhandle. Tornadoes in Texas generally occur in the months of April, May, and June. Some of the most destructive hurricanes in U.S. history have impacted Texas.

4. I NTRODUCTION TO FLOODS Floods are destructive and it brings diseases to human and destroys everything we have. People died from floods too. There are different types of floods. The different kinds of floods are Riverine Floods, Estuarine Floods, Coastal Floods, Catastrophic Floods, Muddy Floods, Flash Floods and Others.

5. R IVERINE F LOODS, E STUARINE F LOODS AND C OASTAL F LOODS. Riverine Floods Slow kinds: Runoff from sustained rainfall or rapid snow melt exceeding the capacity of a river's channel. Causes include heavy rains from monsoons, hurricanes and tropical depressions, foreign winds and warm rain affecting snow pack. Fast kinds: flash flood as a result of e.g. an intense thunderstorm. Estuarine floods Commonly caused by a combination of sea tidal surges caused by storm-force winds. A storm surge, from either a tropical cyclone or an extra tropical cyclone, falls within this category. Coastal floods Caused by severe sea storms, or as a result of another hazard (e.g. tsunami or hurricane). A storm surge, from either a tropical cyclone or an extra tropical cyclone, falls within this category.

6. C ATASTROPHIC F LOODS, M UDDY F LOODS, F LASH F LOODS AND O THERS. Catastrophic floods Caused by a significant and unexpected event e.g. dam breakage, or as a result of another hazard (e.g. earthquake or volcanic eruption). Muddy floods A muddy flood is generated by run off on crop land. Others Floods can occur if water accumulates across an impermeable surface (e.g. from rainfall) and cannot rapidly dissipate (i.e. gentle orientation or low evaporation). A series of storms moving over the same area. Dam-building beavers can flood low-lying urban and rural areas, often causing significant damage. Flash floods Flash floods are caused by sudden torrential flows following a brief, intense rainstorm or the bursting of a natural or man-made dam or levee.

7. N ATURAL CAUSES OF FLOODS High rainfall Water level increases because of rain. Flooding will occur if water exceeds the capacity of the water body. Snowmelt Over many years, the temperature of Earth went up rapidly because of Global Warming. Snow would melt in Spring and flow back to the water bodies. If the water body cannot contain all of the water, the place will flood. Relief Lowlands are prone to floods as rivers flow more slowly in low-lying area. So if the water volume suddenly increases,floods occur. Coastal flooding It is common for coastal areas to flood as the tides there are high. Flooding would result if the water level is higher than the land.

8. H UMAN CAUSES OF FLOODS Deforestation The large areas of forest that is near the rivers have been cleared for settlement, roads and farmland. There are less vegetation that will protect the soil and most of it goes into the rivers. The river banks rises, and so the river overflows its banks easily Water not soaked up by trees and more water flows into the rivers. Soil erosion occurs when there are no plants to hold the soil and thus, it is washed into the rivers by rain.. The river bed gets shallower because of silting. When the amount of water goes up, there is no way that the river can hold all the water but to overflow its own banks.

9. H UMAN CAUSES OF FLOODS Poor farming Some farming practices can damage the vegetation cover, so the soil will be washed into the river easily. Overgrazing People want more food and money, they graze too many animals on the land and the pasture is eaten away quickly. Less vegetation cover, soil washed into the rivers easily. Over cultivation When a piece of land has been used for farming for a long period of time, the soil may became so infertile that no vegetation can grow on the land less fertile than before, so the soil washed into the rivers more easily. Poor water management When the dams are poorly constructed or maintained,they can easily collapse and this results in flooding. Population pressure Because of large amount of people, everything need more, like wood, land and food. Soil erosion happen more often, it increases the risk of flooding.

10. That’s all guys! Thank you for your attention!