Q&A Hero

Q: In easy and fairly accurate method for estimating potential evapotranspiration for most midlatitude locations utilizes mean air temperature and daylength.

Q: Precise measurements of evapotranspiration are difficult.

Q: In the United States, evapotranspiration tends to be highest in the southwest.

Q: The highest precipitation values in the United States occur in the Great Plains region.

Q: Potential evapotranspiration is a measure of water demand.

Q: A water budget is derived from measuring system inputs of precipitation and system outputs of evapotranspiration and runoff.

Q: The water-balance methodology is, in essence, an accounting or bookkeeping system for water resource analysis.

Q: On a hot day, a tree can transpire hundreds of liters of water.

Q: About 50% of precipitation over the land infiltrates the surface, of which 75% returns to the atmosphere via evapotranspiration.

Q: When the soil is saturated, additional inputs of water may puddle on the surface or flow downslope as overland flow.

Q: Precipitation intercepted by plants may eventually reach the Earth's surface through stem flow.

Q: Though 14% of global evapotranspiration occurs over the land, 22% of global precipitation occurs over land, indicating a contribution from evaporation from the world's oceans.

Q: Transpiration refers to the release of water to the atmosphere from the Earth's crust.

Q: Most evaporation occurs over the land surface.

Q: The three main components of the hydrologic cycle are atmosphere, surface, and subsurface.

Q: By volume, the Pacific Ocean is the largest ocean basin.

Q: There is more groundwater than there is water in freshwater lakes, the atmosphere, and rivers and streams combined.

Q: Combined, water in the atmosphere and in rivers and streams accounts for approximately 4% of all freshwater.

Q: Of all the surface freshwater on Earth, over 99% is in ice and glaciers.

Q: Less than 3% of Earth's waters are classified as fresh water.

Q: The Northern Hemisphere is dominated by oceans, whereas the Southern Hemisphere is dominated by land masses.

Q: Oceans and land surface are distributed evenly on the Earth.

Q: Sea-level change caused by glacial activity is known as glacioeustasy.

Q: Water is the third most common compound on the surface of the Earth, after carbon dioxide and methane.

Q: An erupting geyser is an example of outgassing.

Q: Water and water vapor is entered Earth's early atmosphere through outgassing and eventually led to the formation of the Earth's ponds, lakes, seas, and, eventually, oceans.

Q: Water is a renewable resource, constantly cycling through the environment in the hydrologic cycle.

Q: The overall quantity of water on Earth is constantly fluctuating as evidenced by changes in sea level.

Q: Which of the following is not considered an issue pertaining to water resources in the future?A) Growing populations will continue to exploit water resources.B) Pollution will limit the water-resource base.C) Regional drought will increase pressure on groundwater resources.D) Desalination will exacerbate dwindling freshwater supplies.

Q: The High Plains aquifer A) has little importance as a freshwater resource. B) was not heavily mined until the 1960s. C) is also known as the Garber-Wellington Aquifer. D) is North America's largest known aquifer system.

Q: Which of the following is an example of the consumptive use of water? A) water which evaporates from an irrigated field B) hydroelectric power production C) using water for a bath D) river navigation

Q: The permanent remove of water from the immediate water environment is known as A) water withdrawal. B) nonconsumptive use. C) consumptive use. D) offstream.

Q: Approximately ________ countries are currently experiencing water shortages. A) 5 B) 10 C) 80 D) 165

Q: Which of the following is not necessary for an aquifer to exist? A) porosity B) permeability C) hygroscopic water D) zone of saturation

Q: Excess surface water percolates through the zone of ________ to reach the zone of ________ and the water table. A) hydration; infiltration B) porosity; permeability C) dehydration; hydration D) aeration; saturation

Q: The largest practical potential source of fresh water in North America is A) groundwater. B) ice sheets and glaciers. C) stream discharge. D) soil moisture.

Q: Which of the following is true regarding groundwater? A) It is unlimited when compared with the amount of surface water supplies. B) When polluted, it is actually easier to clean up than is surface water. C) The total amount of groundwater has been reduced by the mining of water. D) In terms of total amount, it is second to streams in the United States.

Q: Which of the following is a potential source of groundwater pollution? A) septic tanks B) pesticides and fertilizers C) dumps D) septic tanks, pesticides and fertilizers, and dumps

Q: The term "cone of depression" refers to A) a change in the level of the soil water zone. B) a depression in the water table formed by rapid groundwater withdrawal. C) a depression in Earth's surface formed by groundwater withdrawal. D) a graphical representation of the decline in the rate of groundwater flow as an aquifer dries out.

Q: The term "groundwater mining" refers to A) the removal of overlying rock to reach groundwater. B) the excavation of tunnels to reach groundwater. C) the use of groundwater to mine minerals. D) the removal of groundwater at a rate faster than that at which it can be replaced.

Q: A water-bearing rock stratum is called a(n) A) water table. B) aquiclude. C) zone of aeration. D) aquifer.

Q: The line of contact between the zone of aeration and the zone of saturation is known as the A) water table. B) saturation contact. C) influent line. D) aquiclude.

Q: Which of the following accurately describes annual groundwater withdrawal in the United States and Canada? A) Withdrawals increased 150 percent between 1950 and 2000. B) The percentage of withdrawals in the United States and Canada are about the same. C) Groundwater pumping is presently not exceeding water recharge rates. D) The amount withdrawn is equal to river discharges in the United States.

Q: The utilization of aquifers beyond their flow and recharge capacities is known as A) the potentiometric surface. B) influent conditions. C) groundwater mining. D) the contact surface.

Q: Drawdown refers to A) the potentiometric surface of an aquifer. B) effluent conditions where groundwater feed streamflow. C) the aquifer recharge area. D) the lowering of an aquifer from overuse

Q: Which condition may exist when the pontentiometric surface is above ground level A) artesian water may rise to the surface. B) drawdown in the well. C) groundwater recharge of the aquifer. D) a confined aquifer may become an unconfined aquifer.

Q: If one were to map a vertical profile of groundwater resources, which of the following is correct order from top to bottom? A) zone of aerationwater tablezone of saturationimpermeable rock B) water tablezone of aerationzone of saturationimpermeable rock C) zone of aerationzone of saturationwater tableimpermeable rock D) zone of saturationwater tablezone of aerationimpermeable rock

Q: The main source of groundwater is A) hygroscopic water in the soil. B) surface water where it intersects the zone of recharge. C) precipitation that percolates downward as gravitational water. D) the zone of aeration above the water table.

Q: Approximately what percent of the U.S. population derives a portion of its fresh water from groundwater sources? A) 10 percent B) 30 percent C) 50 percent D) 90 percent

Q: Approximately what percent of the world's irrigation water is from groundwater? A) 15 percent B) 25 percent C) 50 percent D) 80 percent

Q: Which of the following is not a freshwater wetland? A) Tidal marsh. B) Bog. C) Peatland. D) Swamp.

Q: The water in wetlands is A) always freshwater. B) always saltwater. C) either freshwater or saltwater. D) too polluted to use as a water resource.

Q: The California Water Project is A) a proposed dam of the Colorado River between the Parker and Palo Verde Dam. B) a multi-year plan designed to harvest rainwater for agricultural purposes. C) a water conveyance system to distribute water resources throughout the state. D) an ambition goal to build a hydroelectric power station larger than China's Three Gorges.

Q: The Colorado River is an exotic stream. This means A) it contains a variety of exotic species, which it transports from its source to all regions through which it flows. B) it mostly flows through arid environments, though its headwaters are located in a region of water surplus. C) it is used for multiple purposes, including hydroelectricity generation, irrigation, water supplies, and recreation. D) it crosses multiple countries, as well as states, in its path to the sea.

Q: Which of the following is not a cited benefit of China's Three Gorges Dam on the Yangtze River? A) hydroelectric power B) redistribution of water supplies C) pollution abatement D) flood control

Q: Hydropower power currently provides the world with approximately ________ of the world's electricity. A) 1/2 B) 2/3rds C) 1/4th D) 1/5th

Q: The largest reservoir in the world by volume is A) Lake Nasser. B) Lake Kariba. C) Lake Votka. D) Lake Guri.

Q: The largest fresh water lake in the world by volume is A) Lake Superior. B) Lake Baikal. C) Lake Tanganyika. D) Lake Michigan.

Q: Which of the following is not an example of a potential surface water resource? A) artificial lakes B) aquifers C) glaciers D) rivers

Q: Berkeley, CA has the highest amount of precipitation during the A) Spring. B) Summer. C) Autumn. D) Winter.

Q: Actual evapotranspiration for Phoenix, Arizona is highest during A) March. B) February. C) September. D) July.

Q: Potential evapotranspiration for Phoenix, Arizona is highest during A) March. B) February. C) September. D) July.

Q: The water balance for Kingsport, Tennessee exhibits A) a net water surplus (SURPL) during each month of the year. B) net demands for water for 10 months of the year. C) water deficits in the summer months. D) water deficits each month of the year.

Q: The texture and structure of the soil dictate all of the following except A) the wilting point B) available pore spaces (i.e., the soil's porosity). C) flow of water through soil (i.e., the soil's permeability). D) hygroscopic water. E) the field capacity.

Q: The difference between the wilting point and field capacity is approximately equal to A) wilting point water. B) gravitational water. C) available water. D) hygroscopic water.

Q: A water surplus occurs when A) the potential evapotranspiration demand cannot be satisfied by precipitation inputs. B) the additional inputs of water into a system are not enough to satisfy potential evapotranspiration. C) additional water exists after potential evapotranspiration is satisfied by precipitation inputs. D) potential evapotranspiration is greater than soil moisture.

Q: Which of the following is normally true of a hot desert? A) Potential evapotranspiration exceeds actual evapotranspiration. B) Actual evapotranspiration exceeds potential evapotranspiration. C) Potential evapotranspiration equals actual evapotranspiration. D) It is impossible to say what the normal relationship between potential and actual evapotranspiration would be in a desert.

Q: A drought defined based on the supply and demand of water resources is a(n) A) meteorological drought. B) agricultural drought. C) hydrological drought D) socioeconomic drought.

Q: A drought defined based on decreases in streamflow, lowering of reservoir levels, and declines in snowpacks is a(n) A) meteorological drought. B) agricultural drought. C) hydrological drought D) socioeconomic drought.

Q: A drought defined by the shortage of precipitation and soil moisture effects on crop yield is a(n) A) meteorological drought. B) agricultural drought. C) hydrological drought D) socioeconomic drought.

Q: A drought defined by the degree of dryness as compared to a regional average and the duration of dryness is a(n) A) meteorological drought. B) agricultural drought. C) hydrological drought D) socioeconomic drought.

Q: The amount of water associated with the wilting point in clay is ________ than that for sand and silt. A) greater B) less C) approximately the same

Q: Of the following, which soil type has the highest field capacity? A) loam B) clay loam C) silt loam D) sandy loam

Q: Which of the following is true when the soil is at field capacity? A) A surplus definitely exists. B) No gravity drainage has occurred. C) The soil is holding the maximum amount of water that it can hold against the pull of gravity. D) The capillary force is not acting.

Q: Which of the following types of water is accessible to plants? A) hygroscopic B) capillary C) deficit water D) transpired water

Q: Soil moisture tightly bound to each soil particle and unavailable for plant use is termed ________ water. A) capillary B) gravitational C) available D) hygroscopic

Q: Soil moisture that plants are capable of accessing and using is called A) wilting point water. B) free molecular water. C) capillary water. D) hygroscopic water.

Q: Actual evapotranspiration (ACTET) is determined by A) precipitation - deficit. B) precipitation - surplus. C) actual evapotranspiration - surplus. D) potential evapotranspiration - deficit.

Q: Actual evapotranspiration (ACTET) is determined by A) deficit subtracted from Precipitation total. B) surplus subtracted from Precipitation total. C) surplus subtracted from Potential Evaporation. D) deficit subtracted from Potential Evaporation.

Q: If precipitation and soil moisture are inadequate to meet potential evapotranspiration demands, the moisture condition is described as A) actual evapotranspiration. B) a surplus. C) a deficit. D) soil moisture utilization.