the hydrological cycle

Question 1

why is the hydrological cycle important

Answer 1

the movement of water as a liquid, gas and solid throughout the land, oceans and atmosphere is an important part of the earth’s climate system.

this continuous movement of water is known as the hydrological cycle.

Question 2

explain what happens in the water cycle

Answer 2

as water moves through the cycle, it changes state from gas (water vapour) to liquid (rainwater, freshwater, seawater), to solids (ice, hail) and back to gas.

Question 3

why is the water cycle important

Answer 3

this natural cycle removes some of the water impurities and constantly recycles the earths fresh water supplies

Question 4

what is the driving force behind the hydrological cycle

Answer 4

solar energy

Question 5

some of the parts of the water cycle

Answer 5

evaporation
condensation
precipitation
photosynthesis
runoff

Question 6

what is evaporation

Answer 6

evaporation is the process of water changing its physical state from liquid t gas and requires an input of energy to occur.

Question 7

where does most evaporation occur

Answer 7

most evaporation comes from the oceans as they cover 70% of the earth’s surface, with smaller amounts coming from other water bodies such as rivers and lakes

Question 8

what happens when ocean water is evaporated

Answer 8

as ocean water evaporates it leaves behind salt, minerals and metals so only freshwater makes its way to the atmosphere.

Question 9

how long does a water molecule spend in the air

Answer 9

about 10 days n average

Question 10

what is condensation

Answer 10

condensation is the process of water changing its physical state from gas to liquid.

Question 11

what happens in this process (condensation)

Answer 11

as water vapour rises, it becomes cooler and its physical state changes back into tiny liquid water droplets

depending on weather conditions, water molecules will combine with tiny particles of dust, salt and smoke in the air to form water droplets, which coalesce, grow, and develop into clouds

as water droplets coalesce, or combine with each other, clouds develop, and precipitation may also occur

Question 12

what is the size of water droplets

Answer 12

water droplets vary in size with some being ten micros (millionths of a metre) to 1 millimetre to as large as 5 millimetres

Question 13

what is coalesce

Answer 13

come together to form one mass or whole

Question 14

what is precipitation

Answer 14

precipitation occurs when rain, snow or hail falls from the sky.

when enough liquid water has condensed and the atmosphere cannot support its weight, gravity ensures that the water falls from the clouds back to earth.

Question 15

what form is precipitation in

Answer 15

water can take a liquid form (rain) or a solid form (snow/sleet/hail) depending on the air temperature.

Question 16

what is virga

Answer 16

precipitation may also evaporate before it reaches the earth’s surface, this is known as virga

Question 17

what is infiltration

Answer 17

as precipitation in the form of rain occurs, waterfalls to the earth where some of it soaks or infiltrates into the ground.

Question 18

what is the process of infiltraction

Answer 18

it is then collected underground in aquifers- layers of permeable rock, sand or gravel- and this is known as ground water

Question 19

where does groundwater go

Answer 19

groundwater will eventually seep into the rivers, creeks, lakes or other water storage bodies, thereby providing a steady flow of water even after the rain has stopped

Question 20

when does runoff occur

Answer 20

runoff occurs when water does not soak into the ground, but rather flows across the land island.

Question 21

what is that water in runoff called

Answer 21

is referred to as surface water and collects in creeks, streams, rivers and lakes that may flow into seas and oceans, allowing the cycle to continue

Question 22

describe how runoff can occur with snow

Answer 22

if the temperature is cold enough the precipitation will take the form of snow on top of mountains or on the ground. this snow will eventually melt and either runoff into rivers and other water bodies, which is known as snowmelt runoff

Question 23

where else can runoff go to

Answer 23

it can also infiltrate into the ground and collect in aquifers, as with rainwater

Question 24

what is sublimination

Answer 24

snow and ice also evaporate directly from their frozen form to vapour this process is known as sublimation

Question 25

what is photosynthesis

Answer 25

plant roots also absorb water in the ground. this water is then available for the plant to use in the process of photosynthesis

Question 26

what are plant circulation systems powered by

Answer 26

by the evaporation of water from pores in the plant’s leaves- a process known as transpiration.

Question 27

describe the plant circulation systems

Answer 27

this process equals 10% of water vapour in the atmosphere and plays a vital role in maintaining atmospheric moisture levels as clouds move away from oceans

Question 28

what is evapotranspiration

Answer 28

the combined evaporation from water sources, the soil, and the transpiration from plants is known as evapotranspiration

Question 29

what process does the hydrological cycle regulate

Answer 29

rainfall
humidity
cloud cover temperature

Question 30

what does an undisturbed hydrological cycle create

Answer 30

long-term climatic patterns, to which
soil
vegetation
plants
human settlements have adapted

Question 31

what would an alteration in the hydrological cycle create

Answer 31

any alteration in the hydrological cycle such as an increase in temperature which would amplify processes such as evapotranspiration can have significant impacts on Earth’s climate