Q&A Hero

Q: Intercepted water that drains across plant leaves and down their stems to the ground is known as A) throughfall. B) overland flow. C) infiltration. D) stem flow.

Q: An estimated ________ percent of the Earth's precipitation occurs over oceans. A) 8 B) 14 C) 22 D) 78

Q: ________ occurs when precipitation lands on vegetation or other land cover before reaching the surface. A) Infiltration B) Overland flow C) Interception D) Surface runoff

Q: Evapotranspiration from the Earth's land surface represents ________ percent of water entering the atmosphere. A) 44 B) 86 C) 14 D) 78

Q: Transpiration refers to A) the movement of free water molecules away from a wet surface. B) the outward movement of water from plant leaves. C) an amount of moisture loss from the surface that cannot be measured. D) evaporation.

Q: The movement of water into the atmosphere from plants is A) precipitation. B) evaporation. C) transpiration. D) sublimation.

Q: The net movement of free water molecules away from a wet surface into air that is less than saturated is known as A) precipitation. B) evaporation. C) deposition. D) sublimation.

Q: An estimated ________ percent of the Earth's evaporation occurs over oceans. A) 97 B) 86 C) 71 D) 16

Q: The hydrologic cycle A) involves the continuous movement of water in all its states throughout the lower atmosphere, biosphere, lithosphere, and hydrosphere. B) is limited to freshwater circulation in the hydrosphere. C) refers to the highly localized transfer of water from plants and soils to the atmosphere and back. D) is the groundwater component of the global water cycle.

Q: Which of the following is not a main component of the hydrologic cycle? A) atmosphere B) surface C) cryosphere D) subsurface

Q: Which of the following is true regarding freshwater on Earth? A) Most of it is in large lakes. B) Most of it is frozen in glaciers and ice caps. C) Most of it is in freshwater lakes, rivers, and streams. D) Most of it is groundwater.

Q: Which of the following is true regarding the amount of water in rivers, streams, and the atmosphere? A) They contain 0.033 percent of the world's fresh water supply. B) Combined, they contain the majority of the world's freshwater. C) The amount of the world's fresh water in rivers and streams is greater than that in the atmosphere. D) They contain 11.02% of the world's fresh water supplies.

Q: The ________ Ocean contains the largest volume of water. A) Atlantic B) Pacific C) Arctic D) Indian

Q: Other than ice sheets and glaciers, the largest repository of fresh water is located in A) lakes and saline seas. B) groundwater. C) soil moisture storage. D) rivers and streams.

Q: About 50 percent of the 125,000 (30,000 ) of freshwater in lakes is A) located in just seven lakes. B) located in the 40 largest lakes. C) saline. D) in the Great Lakes.

Q: Earth's oceans possess A) most of the fresh water on Earth. B) about the same amount of water as is in the atmosphere. C) fifty percent of Earth's waters. D) ninety-seven percent of Earth's waters.

Q: The largest portion of fresh water today is located in A) clouds. B) groundwater resources. C) ice caps and glaciers. D) the major rivers and lakes of the world.

Q: Which of the following is true of the distribution of land and water on Earth? A) The Southern Hemisphere is dominated by water. B) The Northern Hemisphere is dominated by water. C) They are evenly distributed in both hemispheres.

Q: Glacio-eustatic factors refer to A) changes in the total amount of water on Earth. B) a steady-state equilibrium in the water system. C) changes in sea level related to the increase or decrease in quantities of ice. D) changes in sea level related to the melting of icebergs.

Q: Eustasy refers to A) changes in the total amount of water on Earth. B) a steady-state equilibrium in the water system. C) the amount of new water from outgassing volcanoes. D) worldwide changes in sea level.

Q: Outgassing refers to A) changes in the total amount of water on Earth through evapotranspiration. B) a steady-state equilibrium in the water system caused by cycles of evaporation and condensation. C) the dynamic equilibrium between surface and ocean water. D) process in which water and water vapor emerge from deep layers within and below the Earth's crust.

Q: Much of Earth's water supply originated from A) asteroids. B) icy comets. C) gases expelled from the Sun; i.e., solar wind. D) photosynthesis.

Q: Which of the following is true? A) Water has been discovered on no other planet. B) There is no evidence of water ever existing on Mars. C) Water occurs in significant quantities only on Earth. D) Ice has not been detected below the surface of our Moon.

Q: Water covers approximately ________ of Earth's surface. A) 50 percent B) 90 percent C) 25 percent D) 71 percent

Q: Discuss nonconsumptive use, consumptive use, and instream use as it pertains to the area in which you live.

Q: Discuss the different aspects of groundwater storage and movement below the surface. Include the ways in which groundwater comes to the surface on its own, or is drawn to the surface by humans, along with the consequences.

Q: Briefly describe the various surface water resources. Which resources are available in your area? What are the large water projects in your area, such as water transfer projects or dams?

Q: Define the following: soil-moisture storage, hygroscopic water, wilting point, capillary water, field capacity, gravitational water, soil-moisture recharge, soil porosity, and soil permeability.

Q: Define these components of the water budget, explaining the importance of each: precipitation (PRECIP), potential evapotranspiration (POTET), actual evapotranspiration (ACTET), and soil moisture storage (STRGE).

Q: What are the two basic pathways precipitation can take once it reaches Earth's surface?

Q: Draw and label a diagram of the hydrologic cycle.

Q: Describe the hydrological cycle, including its different components.

Q: Describe the location and percentage of all water on Earth. Where are the largest repositories; where are the smallest repositories?

Q: Dams and other water projects result in the redistribution of water over both space and time.

Q: Water availability per person is expected to increase within the next 50 years.

Q: Water quantity and quality are pressing issues for water resource managers.

Q: Both overconsumption and pollution pose issues for water resource management.

Q: Water resources represent a transboundary resource, with river basins and other water sources crossing into multiple countries, states, or other jurisdictional boundaries.

Q: Center pivot agriculture which pumps water from an aquifer is an example of instream water use.

Q: The permanent removal of water from its source is known as consumptive use.

Q: Nonconsumptive water use involves the return of water to its source after use.

Q: Desalination removes organic compounds, debris, and salinity from seawater and represents a method to provide potable water for domestic use.

Q: The water table in the High Plains aquifer has dropped more than 30m (100 ft) in the last five decades.

Q: The High Plains aquifer irrigates about one-fifth of all U.S. cropland.

Q: The largest known aquifer system in North America is the High Plains Aquifer (Ogallala Aquifer).

Q: The largest sector of daily water withdrawals in the water budget for the United States is presently that taken for agricultural purposes.

Q: The utilization of aquifers beyond their flow and recharge capacities is known as groundwater mining.

Q: The general term for the lowering of water table of an aquifer through pumping is the potentiometric surface.

Q: An aquifer is an impermeable surface through which groundwater flow is restricted.

Q: The upper limit of the zone of saturation is known as the water table.

Q: Because groundwater can be recharged through percolation, overconsumption is not currently a concern.

Q: By current estimates, groundwater provides approximately 25% of the world's irrigation water.

Q: Groundwater represents the largest potential freshwater source on Earth.

Q: Population growth and wasteful water usage threaten to produce water shortages in many nations of the world.

Q: groundwater pollution that our generation creates will persist far into the future (decades to centuries) because it is virtually impossible to clean an aquifer once it is polluted.

Q: A stream which receives water flowing from the surrounding aquifer is known as influent, whereas a streamflow which feeds groundwater is known as effluent.

Q: If the water table reaches the surface of the ground, a spring could develop.

Q: An artesian well, by definition, requires pumping because there is otherwise not enough pressure to bring the water to the surface.

Q: A confined aquifer is under the pressure of its own weight, creating a pressure level called the potentiometric surface to which water can rise on its own.

Q: The difference between a confined and unconfined aquifer is determined by whether there is solid, impermeable surface beneath the aquifer.

Q: Precipitation is the main source of groundwater, percolating downward as gravitational water from the soil moisture zone.

Q: States and countries have constructed networks of pipelines and aqueducts to transfer water from one geographic area to another.

Q: The environmental effects of damming rivers for hydropower are minimal.

Q: Human made lakes are generally called reservoirs.

Q: There is little evidence to support that changes in the thermal structure of lakes may block the mixing between surface and deep waters.

Q: Warming temperatures can lead to both increases and decreases in lake levels.

Q: Meltwater from glaciers and snowpacks provide water for humans in many parts of the world.

Q: Socio-economic factors are not considered when evaluating the effects of drought.

Q: There is a single, universally accepted definition of drought scientists use to classify such events.

Q: The same amount of rain can result in different field capacities depending upon the soil type.

Q: Gravitational water is water bound to soil by gravity.

Q: Soil permeability depends on soil particle size, shape, and packing of soil grains.

Q: Capillary water is held in the soil against the pull of gravity by surface tension and hydrogen bonding.

Q: Potential evapotranspiration (POTET), when reduced by the deficit (DEFIC), yields the actual evapotranspiration value for a given time period.

Q: Potential evapostranspiration is a direct measurement of the amount of evapotranspiration that occurs in a given area during a given period of time.

Q: Soil and rock that are less than saturated through which gravitational water moves is known as the zone of aeration.

Q: Field capacity and wilting point are both influenced by soil texture.

Q: At wilting point, no water remains in the soil.

Q: Soil moisture deficits are frequently overcome by irrigation in the arid and semi-arid agricultural regions of the world.

Q: Hygroscopic water and gravitational water are available for plant use.