MIDTERM

Question 1

study of the occurrence, movement,
distribution, and quality of water throughout the earth.

Answer 1

Hydrology

Question 2

Branch of physical geography which is concerned
with the origin, distribution, and properties of the
waters of the earth.

Answer 2

HYDROLOGY

Question 3

study the physical processes in the
atmosphere, specifically weather and climate.

Answer 3

METREOLOGY

Question 4

Meteorological approach to
hydrologic problem

Answer 4

HYDROMETEOROLOGY

Question 5

Importance of Hydrology

Answer 5

(1) Estimating reservoir storage capacity
(2) Planning water resources projects, the peak discharge
and its volume of flood.
(3) Estimating the impact of watershed management on the
quantity and quality of the surface and the groundwater
resources.
(4) Planning an integrated water resources development
master plan for a basin.
(5) Trans-boundary river water allocation problems, and
(6) Delineation of probable flood levels to plan protection
of settlements and projects from flooding or to promote
better zoning.

Question 6

study of the transfer of water and
energy between land and water body surfaces and the
lower atmosphere

Answer 6

HYDROMETREOLOGY

Question 7

study of the hydrologic processes
that operate at or near the Earth’s surface.
 Rivers, dams, lakes
 Issues on eroding soils and streams due to surface
flow

Answer 7

Surface Hydrology

Question 8

“geohydrology”, study of the presence
and movement of water in aquifers and shallow porous
media.

Answer 8

Hydrogeology

Question 9

drain basin management;
covers water storage and flood protection.

Answer 9

Watershed Management –

Question 10

chemistry of water in rivers and lakes,
both of pollutants and natural solutes.

Answer 10

Water Quality

Question 11

– study of chemical characteristics of
water.

Answer 11

Chemical Hydrology

Question 12

Study of ecological processes in the
hydrologic cycle.

Answer 12

Ecohydrology –

Question 13

Adaptation of information technology
to hydrology and water resources applications

Answer 13

Hydroinformatics

Question 14

– study of the isotopic signatures of
water.

Answer 14

Isotope Hydrology

Question 15

Continues chain of movement and
interchange of water between oceans, atmosphere and
land surface and below the land surface.

Answer 15

Hydrologic Cycle –

Question 16

Four Basic Components

Answer 16

 Evaporation and
transpiration
 Precipitation
 Groundwater
 Runoff

Question 17

water vapor is discharged to the
atmosphere as a result of —— from the soil.

Answer 17

. Evaporation –

Question 18

– process by which water is changed from
vapor to liquid.

Answer 18

Condensation

Question 19

discharge of water, in liquid or solid state,
out of the atmosphere, generally upon a land or water
surface.

Answer 19

. Precipitation –

Question 20

release of water from plant leaves. Every
day, an actively growing plant transpires 5 to 10 times as
much water as it can hold at once. 10% of the moisture
found in the atmosphere is released by plants.

Answer 20

Transpiration –

Question 21

Tinier dust, salt, or smoke particles in
which water droplets must condense with for precipitation
to happen.

Answer 21

Condensation Nuclei –

Question 22

is precipitation trapped by vegetation
instead of falling directly onto the soil.

Answer 22

Interception –

Question 23

when the rainfall is heavy and the soil saturated,
water flows over the land called _____

Answer 23

Runoff –

Question 24

– Precipitation runoff which travels
over the soil surface to the nearest stream channel.

Answer 24

Surface Runoff

Question 25

water getting infiltrate into previous soil mass making it ways towards the rivers and lakes

Answer 25

Subsurface Runoff –

Question 26

movement of water in a natural channel, such as river

Answer 26

Streamflow –

Question 27

downward movement of water from the land surface into soil or porous rock

Answer 27

Infiltration –

Question 28

downward movement of groundwater through cracks, joints and pores in soil and rocks until it reaches the water table where it becomes groundwater.

Answer 28

Percolation

Question 29

lateral movement of groundwater.

Answer 29

Seepage

Question 30

movement of water out of the ground.

Answer 30

Groundwater Discharge

Question 31

water existing for long periods below the Earth’s surface.

Answer 31

Groundwater storage –

Question 32

level at which water stands in a shallow well.

Answer 32

Water Table –

Question 33

water fills all the spaces in the rock.

Answer 33

Zone of Saturation –

Question 34

water does not fully saturate the pores.

Answer 34

Zone of Aeration –

Question 35

divides one zone from the other

Answer 35

Water Table –

Question 36

geologic formation which contains water and transmits it at a rate sufficient to be economically developed for pumping;

Answer 36

Aquifer –

Question 37

occurs in two ways:  When precipitation exceeds the infiltration rate  When the soil is saturated

Answer 37

Overland flow

Question 38

water flowing through the soil in natural pipes percolines (lines of concentrated water flow between horizons).

Answer 38

Throughflow –

Question 39

movement of water within the zone of aeration.

Answer 39

BASEFLOW

Question 40

flow of water within the zone of saturation

Answer 40

INTERFLOW

Question 41

structure or volume in space enclosed by a boundary that accepts water and other inputs, operates on them internally and produces them as output.

Answer 41

Hydrologic System –

Question 42

Six (6) Major Components of Hydrologic Cycle

Answer 42

1. Precipitation 2. Infiltration 3. Evaporation 4. Transpiration 5. Surface Runoff 6. Groundwater

Question 43

part of the atmospheric moisture that falls back on the earth surface.

Answer 43

Precipitation –

Question 44

Brought about by one or more of the following reasons:

Answer 44

1. Adiabatic Cooling 2. Mixing of air masses if varying temperatures 3. Radiation Cooling 4. Contact Cooling

Question 45

3 Ways to Form Precipitation

Answer 45

3 Ways to Form Precipitation 1. Convection 2. Cyclonic 3. Orographic

Question 46

particles of ocean salt, products of combustion and oxides of nitrogen with 0.1 to 10 µm in diameter.

Answer 46

Condensation or Sublimation (Freezing) Nuclei –

Question 47

– fusion of water droplets as a result of their coming in contact through air movement and gravitational pull

Answer 47

Coalescence process

Question 48

vapor pressure around water droplets is higher than that over ice crystals, resulting in the condensation of moisture over ice crystals.

Answer 48

Ice Crystals process –

Question 49

tiny liquid water droplets, 0.1 to 0.5 mm Φ.

Answer 49

Drizzle or Mist –

Question 50

.liquid water drops > 0.5 mm Φ.

Answer 50

. Rain –

Question 51

refers to amount of liquid precipitation

Answer 51

RAINFALL

Question 52

Ice coating, generally clear and smooth, formed on exposed surfaces by the freezing of super cooled water deposited by rain or drizzle. Specific gravity...

Answer 52

GLAZE - ≈ 0.8 to 0.9

Question 53

white, opaque deposit of ice granules separated by trapped air and formed by rapid freezing of supercooled water dropsSpecific gravity

Answer 53

RIME - ≈ 0.2 to 0.3

Question 54

composed of ice crystals, chiefly in complex, branched hexagonal form, and often agglomerated into snowflakes (may reach 100 mm Φ). Average specific gravity

Answer 54

≈ 0.1 SNOW

Question 55

balls of ice produced in convective clouds

Answer 55

HAIL

Question 56

– spheroidal, conical or irregular in shape (specific gravity

Answer 56

Hailstones ≈ 0.8)

Question 57

transparent, globular, solid grains of ice formed by the freezing or raindrops or refreezing of melted ice crystals as it falls in a layer of subfreezing air near the surface

Answer 57

SLEET

Question 58

amounts and intensity of rainfall are important since most estimates of runoff rates are based on rainfall data

Answer 58

Measurement of Rainfall –

Question 59

average rainfall depth that falls per time increment.

Answer 59

Rainfall Intensity (usually in mm/hr) –

Question 60

high intensity storms generally last for short period of time.

Answer 60

Duration –

Question 61

very intense storms are not necessarily more frequent the infrequent combination of high intensity and long duration gives larger total amount of rainfall.

Answer 61

Frequency –

Question 62

probabilistic analysis of hydrologic processes deals with the estimation of the chance or likelihood of occurrence of a given event by determining the frequency curve of best fit to samples of hydrologic data

Answer 62

Hydrologic Frequency Analysis –

Question 63

– it realtes the magnitude of a variable to its frequency of occurrence.

Answer 63

Frequency Curves

Question 64

a tool that characterizes an area’s rainfall pattern.

Answer 64

Intensity-Duration-Frequency (IDF) Curve –

Question 65

most hydrologic and agronomic problems require the estimation of the average rainfall depth over an area such as a watershed and cropped area

Answer 65

Areal Precipitation –

Question 66

the simplest of the area averaging methods.

Answer 66

Arithmetic Averages –

Question 67

assumes that the rainfall in an area may be taken as similar to that recorded in the nearest gaging station

Answer 67

THISSEN METHOD

Question 68

the rainfall depths recorded in all the stations in and around an area of interest are plotted on a map of desirable scale.

Answer 68

Isohyetal Method –

Question 69

consist of the root zone (soil water), intermediate zone and transition layer to the zone of saturation.

Answer 69

Zone of Aeration (Vadose zone) –

Question 70

– all voids are filled with water.

Answer 70

Zone of Saturation (Phreatic zone)

Question 71

divides the two major subsurface zones

Answer 71

Water Table –

Question 72

local saturated zones above impervious layer; of limited extent.

Answer 72

Perched Groundwater –

Question 73

contains water and transmits it at rate sufficient to be economically develop for pumping.

Answer 73

Aquifer –

Question 74

does not readily yield water, but may serve as a storage unit for groundwater (e.g. sandy clay)

Answer 74

Aquitard –

Question 75

geologic formation which contains water but is not capable of transmitting (e.g. clay)

Answer 75

Aquiclude –

Question 76

has no interconnected openings and cannot hold nor transmit water.

Answer 76

Aquifuge –

Question 77

has water table serving as upper surface of the zone of saturation.

Answer 77

Unconfined Aquifer –

Question 78

the water level in these wells indicates the position of the water table in the surrounding aquifer

Answer 78

Water table wells –

Question 79

ground water is confined by relatively impermeable layer

Answer 79

Confined or Artesian Aquifer –

Question 80

the upper confining layer is leaky or semi-permeable.

Answer 80

Semi-Confined Aquifer –

Question 81

wells drilled into confined aquifers, water rises to the piezometric level.

Answer 81

Artesian Wells –

Question 82

wells drilled into confined aquifers wherein the piezometric level is above ground.

Answer 82

Flowing Wells –

Question 83

measure of the water retained by the soil formation against the force of gravity

Answer 83

Specific Retention, Sr –

Question 84

the water that can be extracted by gravity flow

Answer 84

Specific Yield, Sy –

Question 85

the fraction of the porosity of an aquifer

Answer 85

Specific Yield, Sy –

Question 86

those with uniform hydraulic conductivity

Answer 86

isotropic Aquifers –

Question 87

those with varying k values.

Answer 87

Anisotropic Aquifers –

Question 88

rate of flow of water at the prevailing water temperature through a vertical strip of the aquifer one foot wide extending the full saturated thickness of the aquifer under a hydraulic gradient of 100%.

Answer 88

Coefficient of Transmissibility –

Question 89

the rate at which water of the prevailing kinematic viscosity is transmitted through unit width of the aquifer under a unit hydraulic gradient.

Answer 89

Transmissibility, T –

Question 90

the volume of water released or added per unit area of aquifer per unit drop or rise in head or pressure.

Answer 90

Storage Coefficient or Storativity, Sc –