Precipitation

Question 1

The process by which water vapor in the air is changed into liquid water.

Answer 1

Condensation

Question 2

The process by which water vaor in the air is changed into solid without becoming liquid.

Answer 2

Sublimation/Deposition

Question 3

All forms of water that forms in the atmosphere and falls back to the earth’s surface.

Answer 3

Precipitation

Question 4

The condensation into water droplest and sublimation into ice crytals of atmosphere water vapor generally occur around?

Answer 4

Condensation/Sublimation Nuclei

Question 5

Principal types of nuclei?

Answer 5

Dusts, Ocean Salt, Products of combustion and oxides of nitrogen, Other particulate of matter (less than a micron in diameter)

Question 6

The primary cause of condensation and hence, is responsible for most precipitation.

Answer 6

Adiabatic Cooling

Question 7

Adiabatic Cooling results mainly from (blank) which results from a (blank)?

Answer 7

Expansion of air mass, Decrease in atmospheric pressure

Question 8

Adiabatic cooling is triggered primary by the?

Answer 8

upward or vertical motion of air mass

Question 9

The other cause of condensation or sublimation aside from adabatic cooling?

Answer 9

Mixing of air mass of varying temperatures, radiation cooling and contact cooling.

Question 10

The (blank) process is when the cloud droplets collide and coalesce or stick together.

Answer 10

Collision - Coalescence

Question 11

Forms of precipitation?

Answer 11

Rain, Snow, Drizzle, Glaze, Sleet, Hail, Graupel

Question 12

Form of water drops of sizes larger than 0.5 mm

Answer 12

Rain

Question 13

Light rain

Answer 13

2.4 mm/hr

Question 14

Moderate Rain

Answer 14

2.5 - 7.5 mm/hr

Question 15

Heavy Rain

Answer 15

> 7.5 mm/hr

Question 16

Consists of ice crystal which usually combine to form flakes.

Answer 16

Snow

Question 17

A fine sprinkle of numerous water droplets of size less than 0.5 mm and intensity less than 1 mm/hr.

Answer 17

Drizzle

Question 18

When rain drizzle comes in contact with cold ground at around 0degC, the water drops freeze to form an ice coating.

Answer 18

Glaze

Question 19

It is frozen raindrops of transparent grains which form when rain falls through air at subfreezing temperature.

Answer 19

Sleet

Question 20

it is a showery precipitation in the form of irregular pellets or lumps of ice of size more than 8 mm.

Answer 20

Hail

Question 21

Also called snow pellets or soft hail, as the (blank) particles are particularly fragile and generally disintegrate when handled.

Answer 21

Graupel

Question 22

Types of Precipitation

Answer 22

Convection Precipitation, Orographic Precipitation, Cyclonic Precipitation

Question 23

Results from the differential heating of air masses near the ground surface resulting in the upward movement of warmer air masses.

Answer 23

Convection Precipitation

Question 24

Precipitation influenced by topography.

Answer 24

Orographic Precipitation

Question 25

Associated with the movement of air masses due to differences in barometric pressure.

Answer 25

Cyclonic Precipitation

Question 26

The mean annual rainfall of the Philippines varies from?

Answer 26

965 - 4,064 mm

Question 27

Receives the greatest amount of rainfall in the Ph?

Answer 27

Baguio City, Eastern Samar, Easrtern Surigao

Question 28

Receives the least amount of rainfall in the Ph?

Answer 28

Southern part of Cotabato

Question 29

What is the average annual rainfall in General Santos City in Cotabato?

Answer 29

978 mm

Question 30

The precipitation is collected and measured in a?

Answer 30

Rain Gauge

Question 31

(Blank) are sometimes referred to as rain gauge.

Answer 31

Pluviometer, Ombrometer, Hyetometer

Question 32

Classifications of rain gauges?

Answer 32

Non - recording gauges, and Recording Gauges

Question 33

Non - Recording Gauges

Answer 33

Symon's Gauge, Standard 8-inch Rain Gauge

Question 34

Recording Gauges

Answer 34

Tipping-Bucket Type, Weighing-Busket Type, Natural-Siphon Type, Telemetering Rain Gauges, Radar Measurement of Rainfall

Question 35

The catch from the funnel falls onto one of a pair of small buckets.

Answer 35

Tipping-Bucket Type

Question 36

The catch from the funnel empties into a bucket mounted on a weighing scale. The weight of the bucket and its contents are recorded on a clockwork - driven chart.

Answer 36

Weighing-Busket Type

Question 37

Also known as float-type gauge. The rainfall is collected by a funnel-shaped collector led into a float chamber using a float to rise.

Answer 37

Natural-Siphon Type

Question 38

Recording type and contain an electronic units to transmit the data on rainfall to a base station both at regular intervals and on interrogation.

Answer 38

Telemetering Rain Gauges

Question 39

Ground-based radars send out pulses of microwave energy in narrow beams that scan in a circular pattern.

Answer 39

Radar Measurement of Rainfall

Question 40

In flat region of temeperate, Mediterranean and tropical zones

Answer 40

Ideal - 1 station for 600 - 900 sq.km, Acceptable - 1 station for 900 - 3000 sq.km

Question 41

In mountainous regions of temeperate, Mediterranean and tropical zones

Answer 41

Ideal - 1 station for 100 - 250 sq.km, Acceptable - 1 station for 25 - 1000 sq.km

Question 42

In arid and polar zones

Answer 42

1 station for 1500 - 10,000 sq.km depending on feasibility

Question 43

(Blank) of rain gauge stations should be equipped with self - recording gauges to know the rainfall intensities.

Answer 43

0.1

Question 44

Based on the principle that when recorded data comes from the same parent population, they are consistent.

Answer 44

Double - Mass Curve

Question 45

Test for consistency of record.

Answer 45

Double - Mass Curve

Question 46

Presentation of Rainfall Data

Answer 46

Mass Curve of Rainfall, Hyetograph, Point Rainfall, Moving Average,

Question 47

Plot of the accumulated precipitation against time, plotted in chronologica; order.

Answer 47

Mass Curve of Rainfall

Question 48

Plot of the intensity of rainfall against the time interval. It is derived from the mass curve and is usually represented in bar chart/graph.

Answer 48

Hyetograph

Question 49

Also known as station rainfall, refers to the rainfall data of a station. Graphically, these data are represented as plots of magnitude vs. chronological time in the form of bar diagram.

Answer 49

Point Rainfall

Question 50

A technique for smoothening out the high frequency fluctuations of a time series and to enable the trend, if any, to be noticed.

Answer 50

Moving Average

Question 51

Mean Precipitation Over an Area

Answer 51

Arithmetic Mean Method, Thiessen Polygon, Isohyetal Method

Question 52

This method is use when rainfall over a catchment show little to no variation.

Answer 52

Arithmetic Mean Method

Question 53

This method is use when the rainfall recorded at each station is given a weightage on the basis of an area closest to the station.

Answer 53

Thiessen Polygon

Question 54

This method is use when the area of two adjacent isohyets are determined and the average value of rainfall indicated by the two isohyets is assumed to be acting over the inter - isohyet area.

Answer 54

Isohyetal Method