Session 1: Introduction to hydrology

Question 1

What is hydrology?

Answer 1

is the science that encompasses the occurrence,
distribution, movement and properties of the waters of the
Earth and their relationship with the environment.

Question 2

What do hydrologists do?

Answer 2

Hydrologists study fundamental transport processes to
describe the quantity and quality of water as it moves
through the hydrological cycle:
– evaporation, precipitation, streamflow, infiltration, groundwater flow,
and other related processes.

Question 3

different sub-branches of hydrology and how they are interlinked

Answer 3

-Hydrometeorology: weather patterns, rainfall & climate.
• Surface hydrology: surficial water flow processes, floods, low flows.
• Groundwater hydrology (hydrogeology): subsurface water flow
patterns and storage.
• Ecohydrology: hydrological cycle  ecosystem interactions.
• Urban hydrology: water flow and quality in urban environments.
• Water quality: water chemistry in rivers/lakes, pollutants and
natural solutes.
• Hydrological models: simplified, conceptual realisations of
hydrological cycle  data based or process description based.
• Stochastic hydrology: applying probabilistic methods to model
hydrological processes with random components (e.g. rainfall).

Question 4

Land management

Answer 4

Agriculture and irrigation

Question 5

Water management

Answer 5

– Provision of drinking water supply

– Reservoir storage, groundwater

Question 6

Flood prevention

Answer 6

-Design of flood prevention schemes

– Sustainable urban drainage systems

Question 7

Drought prevention

Answer 7

Managing water resources

Question 8

what a watershed or catchment is and how it is defined

Answer 8

A catchment or watershed is the total area which drains into a common outlet

Question 9

spatial and temporal scales of interest in hydrology processes

Answer 9

Spatial scales vary from a few meters to hundreds of
kilometers:
– Surface water and groundwater are related at large scales
– Local processes are affected by regional changes.

Question 10

key hydrologic processes for water movement through cycle

Answer 10

Movement of water through hydrological cycle:
– Evaporation
– Condensation
– Precipitation
– Transpiration
– Infiltration
– Abstraction
– Runoff

Question 11

key factors affecting water cycle

Answer 11

-Climate
– Land use
– Catchment
geometry

Question 12

the need for gauging stations around Scotland and UK

Answer 12

• Runoff prediction

– Stream flow prediction

Question 13

absolute humidity?

Answer 13

Amount of water vapour held in

air is absolute humidity (g/kg air)

Question 14

Transpiration?

Answer 14

water absorption by plants (usually through roots)

Question 15

What is runoff?

Answer 15

Portion of precipitation (rain or snow) that
does not percolate into ground and
discharges into streams instead.