3.0 Run-off Analysis

Question 1

(also called drainage basin, or river basin) is the land area where rainfall runs off into streams, rivers, lakes, and reservoirs

Answer 1

watershed

Question 2

is a plot of the average intensity of rainfall against the time interval

Answer 2

hyetograph

Question 3

is a plot of the accumulated precipitation against time

Answer 3

mass curve of rainfall

Question 4

is traditionally measured using various types of rain gages such as the non-recording cylindrical container type or the recording weighing type, float type and tipping-bucket type.

Answer 4

Liquid precipitation

Question 5

used to determine the mean amount of rainfall, and the spatial or areal distribution of rainfall

Answer 5

point rainfall analysis (PRA)

Question 6

PRA techniques

Answer 6

arithmetic mean
isohyetal analysis
thiessen polygon

Question 7

a graphical technique which involves drawing estimated lines of equal rainfall over an area based on point measurements.

Answer 7

isohyetal analysis method

Question 8

is a line joining places where the rainfall amounts are equal on a rainfall map of a basin. Isohyetal lines are mainly based on interpolation between rain gauge stations. It has properties same with contour lines

Answer 8

isohyet

Question 9

lines on a weather map showing places of equal pressure

Answer 9

isobars

Question 10

lines on a weather map showing places of equal temperature

Answer 10

isotherms

Question 11

lines on a weather map indicating equal snowfall depth.

Answer 11

isonifs

Question 12

lines on a weather map connecting points having the same amount (average percentage) of cloudiness.

Answer 12

isonephs

Question 13

graphical technique which calculates station weights based on the relative areas of each measurement station

Answer 13

Thiessen polygon method

Question 14

estimation of the value at a location is a weighted mean of nearby observations

Answer 14

distance weighing/gridded

Question 15

radar based mean areal precipitation

Answer 15

mapX

Question 16

NWS

Answer 16

national weather services

Question 17

provides weather, hydrologic, and climate forecasts and warnings for the united states, its territories, adjacent waters and ocean areas, for the protection of life and property and the enchancement of the national economy

Answer 17

NWS (national weather services)

Question 18

WSR

Answer 18

Weather surveillance radar

Question 19

can detect most pericipitation within approximately 80 nautical miles (nm) of the radar and intense rain or snow within approximately 140 nm.

Answer 19

WSR (Weather surveillance radar)