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Geography 🌍 > Climatology , oceanography > Flashcards

Climatology , oceanography Flashcards

1
Q

What is role of atmosphere

A

Oxygen CO2 and Nitrogen
Regulate solar heat
No harmful UV rays
Control temperature

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2
Q

What are aerosols

A

Solid and liquid particles

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3
Q

What is the order of gases present in the atmosphere

A

Nitrogen > oxygen > argon >co2 > neon> helium> hydrogen

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4
Q

Explain the greenhouse effect

A

Uneven distribution of the ozone block UV rays

Co2 absorbs radiation and gives heat back

Water vapour absorbs infrared and night heat, gives out latent heat which is the force for storm

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5
Q

Explain the structure of the atmosphere

A

EXOSPHERE 500 km = helium and hydrogen temperature is very high

THERMOSPHERE 400-500 km = High-temperature

IONOSPHERE 85-400km = Radio transmission as it is electrically charged

MESOSPHERE 60-85 km = temperature reduces to -100 degrees at 80 km, meteorites

Ozone 30-60km = temperature increases by 5° per kilometre
STRATOSPHERE 10-30km = temperature at 50 km is 0°, no clouds … aeroplanes

TROPOSPHERE 8 to 18 km at equator, tropopause causes temperature inversion, temperature falls at 6.5° per kilometre

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6
Q

What is absolute Humidity

A

Actual amount of water vapour present at the atmosphere

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7
Q

What is relative humidity

A

Absolute humidity compared to humidity at a particular temperature

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8
Q

What is dew point

A

The temperature at which air cannot carry any more moisture

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9
Q

What is specific humidity

A

Weight of water vapour divided by weight of air

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10
Q

What is the insolation

A

Percentage of heat received by the earth

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11
Q

How does earth absorb heat during the day and during the night

A

During the day in short we visible light

During the night in long wave infrared

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12
Q

Discuss the ways of heat transfer on the earth

A

Radiation no contact
Conduction molecular action conductor required
Convection actual transfer of matter

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13
Q

What are the factors that affect the transfer of heat

A
  1. Angle of rays
  2. Duration of sunshine
  3. Transparency of atmosphere
  4. If the radius of particle is greater than wavelength then the light is reflected if it is less then the wavelength then scattering takes place
  5. Land sea differential- Albedo of land is greater than sea Prevailing winds
  6. Prevailing winds
  7. Slope
  8. Or is the distance from sun
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14
Q

What is the meaning of albedo

A

The percentage of light reflected by a surface

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15
Q

When is the earth closest to the sun

A

Fourth of July apehelion

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16
Q

When is the earth farthest from the sun

A

3 jan perihelion

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17
Q

What is latitudinal heat balance

A

The planetary winds and ocean currents cause transfer of excess energy from the tropics to the poles
The energy is transferred at 50° and 30° latitude therefore these are known as storm zones

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18
Q

What is heat budget how is it maintained

A

global heat budget is the balance between incoming and outgoing solar radiation.

Short wave is absorbed and long wave is reflected hence the heat budget is maintained

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19
Q

What are isotherms

A

Isoterms are imaginary lines joining places with same temperature

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20
Q

What are the characteristics of isotherms

A

are parallel latitude since they have similar sunlight

bend at Ocean and continent boundaries since
different heating of land and sea

Narrow space have a rapid changes

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21
Q

Discuss the behaviour of isotherms on the surface of the earth

A

Daily and annual temperature ranges are high at interiors
Lowest temperature radiant is at the tropics since the sun is overhead almost all year
Temperature gradient is low at the eastern margins since warm currents
While passing through warm ocean currents they drift phone words

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22
Q

What is lapse rate

A

Rate of change of temperature moving upwards in the atmosphere

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23
Q

Why does temperature reduce with altitude

A

Greenhouse gases reduce hence heat absorption reduces

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24
Q

Discuss the adiabatic lapse rate

A

When there is no loss of heat and no heat exchange between the parcel and the environment

When the parcel of air receives more heat from surrounding the volume increases and density reduces and it rises this is not an adiabatic process

When the air parcel rises , ambient pressure which is pressure of the surrounding reduces with height hence pressure and temperature reduced and volume increases this is an adiabatic process

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25
Q

What is the significance of the adiabatic lapse rate

A

It defines the stability of the atmosphere

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26
Q

What is latent heat

A

Heat released and observe during the change of phase slg

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27
Q

What is temperature anomaly

A

Mean temperature of a place-mean temperature of parallel latitude Largest at north hemisphere

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28
Q

What is temperature inversion

A

Cooler temperature at lower levels and higher temperature at higher layers

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29
Q

What are the ideal conditions for temperature inversion

A

Long night therefore outgoing heat is greater than incoming heat

Clear skies therefore with radiation heat can escape

Calm and stable air therefore there is no mixing of air

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30
Q

Discuss the various types of temperature inversion

A

Air drainage = in valleys the temperature of lower areas increases with altitude at the slopes hence surface heats and rapidly cools then upper layers … inverted

Ground inversion
Air comes in contact with cooler surface and cools , slowly become cooler than upper areas

Subsidence inversion
Air layer descends , the pressure increases… compressed and heated moved down and heat lower layers hence upper layer is more hotter than the lower layer

Frontal inversion
Cold air mass goes under warm air mass

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31
Q

What are the effects of temperature inversion

A
  1. Determines cloud types
  2. Limits convection
  3. Stop smoke at lower layers
  4. Daily temperature range is small
  5. 0°C and valleys but above air is warm
  6. If the temperature at the surface is less then dew point then there is fog
  7. Stable condition hence less rain
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32
Q

Draw a diagram of the pressure zones of the earth

A 
Polar high -60 - converge
 Sup polar low
——Ferrell cell
——Hadley cell
 Subtropical high =horse 30-5
Equatorial low
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33
Q

Discuss the formation of equatorial low , subtropical high , polar high and subpolar low

A

Direct heat from the sun at equator hence temperature increases and pressure reduces =equatorial low
Air rises due to temperature increases has become light , rises till tropopause , sinks at 30° north and 30° south and hence form subtropical high
@polar sun rays slant hence cold air moves s@n , n@s ….polar high
Air converges and rises up hence low pressure hence subpolar low

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34
Q

What is the ITCZ

A

Low-pressure zone where north east and south west winds converge at the equator

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35
Q

What are the forces of the ITCZ

A

Easterly trade winds Circle at the equator

Air mass

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36
Q

What is the Coriolis force

A

It is the force due to the rotation of the earth which causes the wind to get deflected If object goes from south and west here to the north and west where it is deflected to the eastIt is zero at the equator and it is maximum at the polls

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37
Q

Draw the position of wind on the earth

A

Easterly westerly , north-east trade and South East trade

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38
Q

Which ones are known as the roaring 40s and shreaking 60s why

A

The westerlies are knownThere is ocean in the southern hemisphere hence there is no obstruction in the 45° to 60° south

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39
Q

Discuss the effects of the seasonal winds

A

In the summer the sun moves north word hence low-pressure zone is created
Therefore the south hemisphere winds go to the north hem - tradeCrossing the equator they deflect to the right due to Coriolis force
Have travelled a long way on the ocean hence have collected moisture which is released at the western edge of the Asian landmass
In winter high-pressure zone is created in the northern hemisphere hence north trade winds go to the south from the Tibetan plateau and hence Northeast monsoon is at the east coast of India

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40
Q

Name some local winds and their regions

A 
Chinook at North America
Pampers @ s am 
Foehn  @alps
 Karaburan @ Russia
 Loo 
Sirocco @n af 
Berg @ s af
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41
Q

Discuss the significance of the foehn wind

A

Benefits the Alps
15 to 20°C
Helps in animal grazing

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42
Q

Discuss the significance of loo

A

45 to 50°C
Cause dust storms
During may and June

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43
Q

What is the meaning of geostrophi wind

A

Wind if pressure gradient and Coriolis force are equally balanced

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44
Q

What is jet stream

A

Fast flowing narrow meandering air currents in the atmosphere

Circumpolar narrow concentrated bands of air streams
meandering at high velocity
in the upper troposphere
bounded by the low speed wind
and are a part of the upper level westerlies

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45
Q

What causes jet streams

A

Temperature difference between polar and tropical air masses

46
Q

Between which cells is the polar jetstream , subtropical jet stream located

A

Polar jet stream @ polar and Ferrell cellSubtropical jet stream add Ferrell and Hadley cell

47
Q

Discuss the behaviour of jet streams according to the temperature

A

Straight line if there is maximum temperature contrastIf difference is less then the meandering starts

48
Q

What are Rosby waves

A

Meandering jet streams

49
Q

Why are the polar jet streams slower than the subtropical jet streams

A

Polar jet streams move at 6-9 km/h and
subtropical jet streams move at 10 to 16 km/h

Difference is because of the troposphere thickening at the equator

50
Q

Discuss the features of polar jet stream

A

It is a permanent jet stream
At summer it moves towards the pole
in winter it moves to the equator
Influences the climate of 60° north and 60° south
Determine the path and speed of temperate cyclones

51
Q

Discuss the features and effects of the subtropical jet stream

A

It is a permanent jet stream
It moves by the earths rotation
The whole year it is in the southern hemisphere in summer it moves to the north hemisphere
It is connected to the Indian monsoons

52
Q

Discuss the features of the tropical eastern jet stream

A

Also known as African easterly jet stream
It is between the 5° to 20° north
It is a temporary jet stream
in the summer monsoon it increases convection in India
it is caused by the heating of the Tibetan Plateau

53
Q

Discuss the features of the Somali jet stream

A

It is also known as the south westerly jet stream
In summer it is at North Madagascar and moves towards the south Indian Ocean during winter
it is the most intense in June and August

54
Q

What are the effects of jet stream

A

Maintain the latitudinal heat balance by exchange of air
When jet streams interfere with the surface wind they cause storms
Trace the path of temperate cyclones
They influence the air mass therefore there are prolonged drought or flood periods

AT TEMPERATE REGIONS
Separate cold and warm weather Determine the frontal precipitation and frontal cyclones

55
Q

What is the air mass, where are they located

A

Air with distinctive characteristics in terms of temperature and humidity is called in air massThe flow between the surface and the lower stratosphere

56
Q

What is the condition for formation of an air mass

A

Gentle air
High-pressure
Less fluctuation in pressure
Extensive divergent air

57
Q

Discuss the characteristics of a cold air mass

A

Unstable and turbulent
Cold and moist and Arctic Ocean and southern ocean
Cold and dry at Siberia and North Canada

58
Q

Discuss the characteristics of a warm air mass

A

Stable
Warm and dry and the Sahara desert

Warm and moist at tropical oceans

59
Q

Discuss the characteristics of the continental polar air mass

A

Located at Arctic and northern North America, Eurasia Antarctica
It is cold dry and stable
In the summer it is anti-cyclonic
In the winter it is clear and stable

60
Q

Discuss the characteristics of the maritime polar air mass

A

Located between 40° and 60°
Cold moist and unstable
In the summer it is stable and clear
In the winter it causes fog

61
Q

Discuss the characteristics of continental tropical air mass

A

It is located at Sahara and western Asia and Australia
It is dry hot and stable
It does not go beyond source area

62
Q

Discuss the characteristics of the maritime tropical air mass

A

Located between the Mexican gulf, the Pacific and The Atlantic Ocean
Warm humid and unstable
In summer cause convectional rainfall
In winter cause fog

63
Q

What are the effects of air mass

A

Carry moisture from one place to another

Transport latent heat hence remove heat balance

Cyclones originate by the contact zone of two air masses

64
Q

What is the front

A

Three-dimensional boundaries zone formed between the two converging here message of different physical properties

65
Q

What is frontogenesis

A

War between two air masses the , formation of a front

66
Q

Discuss the characteristics of a front

A

Clockwise in the southern hemisphere
anti clockwise in the northern in this year
Mid latitudinal cyclones are cause by frontogenesis

67
Q

How is a front dissipated

A

It is known as Frontolysis One year must wins over the other

68
Q

State the four types of fronts

A

Stationary front… The surface position does not change hence the height does not changeThe two masses are not able to push each other hence they enter into a draw Wind is parallel to the frontIt causes frontal precipitation and cyclones and floods

Cold front….Cool air mass replaces the warm air massIt causes thunderstorms and tornadoes

Warm front ….Warm air wins over cool airThe warm air mass is too weak to take over hence it was above the cold air massIt causes gradual temperature moderate precipitation

Occluded front ….Cold air mass ad cool air mass catches up to the warm air mass hence pushes the warm air mass between themThe cold air mass was underneath the warm air massExtra tropical cyclones at western Europe

69
Q

What is London smog

A

It is sulfurous smog
Caused by fossil fuels and coal
Increases by dampness and increase in particles

70
Q

What is Los Angeles smog

A

Also known as photochemical smog
It is found in urban areas due to automobiles
When nitrogen reacts with the sun hence ozone is formed
It is light brown in colour and reduces visibility

71
Q

What is haze

A

Dust or other particles that obstruct the clear sky

72
Q

What are the effects of smog

A

Pollution trap by inversion
Precipitation reduces
Sickness

73
Q

Discuss the smog formed by various pollutants their causes and effects

A

Nitrogen and nitrogen oxides
By combustion of oil gas forest fires and lightning
Lower visibility yellow smog and reduced plant growth

Volatile organic compounds
Evaporation of fuels and incomplete combustion eye irritation respiratory diseases and reduced visibility

Ozone
By photolysis of nitrogen
Reduce crop and plant growth, damage plastic and rubber

Peroxyacetal nitrate
By reaction of nitrogen oxide with voc Eye irritation and damage to proteins

74
Q

What is the solution to smog

A

Renewable energy
Manage vehicles Attention to air-quality index
Alkaline scrubber is reduced SO2 and SO3 levels
Green belts in the city to filter air
Reduce coal-fired plants

75
Q

What are the factors affecting the rate of evaporation

A

Amount of water
Temperature
Relative humidity
Surface area
Increase in wind therefore blow out saturated air therefore dry air replaces it hence evaporation
Increase in temperature and reduce in relative humidity and strong winds hence evaporation increases
Evaporation is inversely proportionate to pressure
Inversely proportionate to salinity

76
Q

When does condensation takes place

A

When the dew point is less or greater than the freezing point

77
Q

What happens when the dew point is less than the freezing point

A

Dew = moisture deposit at a cooler surface
Clear sky and calm air and high relative humidity
Temperature is greater than freezing point

Fog= when highly water vapour air mass cools suddenly
Temperature is above freezing point visibility is less than 1 km
Advectional fog - warm air moves over cold air

White frost= condense at cold surface
Temperature is below freezing point and excess moisture is converted into minute ice crystals

Mist = same as fog but greater in moistureVisibility is 1 to 2 km

78
Q

What happens when the dew point is greater than the freezing point

A

Four types of clouds are formed

Cirrus = detached , feathery 
Cumulus = scattered w flat base 
Stratus = large surface , layers 
Nimbus = grey with low ground, shape less
79
Q

What are ocean currents

A

Regular volumes of water in a definite path and direction

80
Q

What are the causes of ocean currents

A

Primary- initiate
Heat by the sun, the water expands and hence it is elevated at the equator which causes a gradient slow from east to west

Winds, the monsoon- for seasonal reversal

Gravity causes gradient variation

Coriolis force the water to the right in northern hemisphere and
to the left in the Southern Hemisphere

secondary - move

Temperature difference cold and dense therefore sinks
Salinity difference higher the salinity dense therefore sinks

81
Q

Discuss the types of ocean currents

A

Surface
at 400 m
Deep water after 400 m
Move all around due to change in gravity and density

Cold ocean currents
Move from cold areas to warm areas
In the equatorial zone they hit the western coast
Above the equatorial zone they hit the eastern coast
Clockwise in the northern hemisphere and anticlockwise in the Southern Hemisphere

Warm ocean currents- opposite of cold ocean currents

82
Q

What are the effects of ocean currents

A
  1. Cold ocean currents form deserts and the tropical region
  2. Cause fog and arid conditions
  3. Warm currents bring rain to the interiors example summer rain at the british type climate
  4. Bring warmness to England and the moderating effect
  5. Mixing of ocean current oxygen therefore fishing ground
  6. Cold and warm mix therefore fog and drizzle
  7. Foggy climate at mixing zones
  8. Warm and moist @ subtropical regions
    dry @ western margin.
  9. Piles of warm water at the tropics therefore cyclones
  10. Ship usually follow the direction of the current
83
Q

Why are hot deserts located between 20 to 30° latitude

A

Rain bearing trade winds blow off shore hence take away the moisture from this region

Westerlies blew away from this region

Winds are desert or cold region belonging

Less cloud formation therefore less moisture

84
Q

What are tides

A

Periodic rise and fall of Sealevel once or twice a day due to the direction of the sun and the moon

85
Q

What is a surge

A

Movement of water by meteorological effects like winds or atmospheric pressure

86
Q

What is the tidal bulge

A

Like an eye Left due to centrifugal force right due to gravity

87
Q

Factors affecting tides

A

Movement of the moon and movement of the sun with respect to the earth
Uneven distribution of water

88
Q

What is semi diurnal tide , diurnal, mixed

A

Semi = 2h+2l per day
12 hours 25 minutes difference between high and low

Diurnal = One high and one low tide per day

Mixed tide @ north am. west coast , variation in height

89
Q

What is spring and neap tide

A

Spring tide is when the sun moon and the earth are in a straight line and
it is a high tide
it takes place on full moon and new moon

Neap tide is when the sun and the earth are in straight line and the moon is perpendicular to the earth
it is a low tide
it takes place seven days after the spring tide

90
Q

What is a perigee and apogee, perihelion , aphelion

what effects do they have on tides

A

Perihelion - When the sun is closest to the earth high tidal range

Aphelion - when the sun is farthest to the earth the tidal range is low

Perigee - when the moon is closest to the earth the tidal range is high

Apogee - when the moon is farthest from the earth the tidal range is low

91
Q

What is ebb

A

Time between high and low tide when the level is low

92
Q

What is flood

A

Time between low and high tide when the level is high

93
Q

What are coral reefs

A

They are an ecosystem of calcerous organisms which secrete CAC03Hard corals make coral reefs

94
Q

How are coral reefs formed

A

They get the carbon from ZOXANTHELAE - Photosynthesis in a protected environment with carbon dioxide from the calcareous organisms

95
Q

What are the conditions required for coral reefs to form

A

Warm water 23 to 27°C therefore in tropics and east margins
Water depth up to 180 feet need sunlight
No cold currents
Salted water free from sediments hence not a delta

96
Q

Where are coral reefs located

A

Great barrier coral reef at the Australian coast

Goa Kerala and Sri Lanka

97
Q

Discuss the types of coral reefs

A

Fringing reefs separates the sea from land forming a border on the land mass
Barrier reef like islands in the sea

Atoll Circular formation where there is no landmass

98
Q

What Is the significance of coral reefs

A

Barrier against erosion
CAC03 production
Subsistence for mangroves
Food chains are developed

99
Q

What are the statistics regarding coral reef bleaching

A

The United Nations has reported that:

70% of the Earth’s coral reefs are threatened,
20% have been destroyed with no hope for recovery,
24% are under imminent risk of collapse
, and an additional 26% are at risk due to longer-term threats.

100
Q

What is coral bleaching what are its causes and effects

A

When corals face stress by changes in conditions such as temperature, light, or nutrients, they expel the symbiotic algae zooxanthellae living in their tissues, causing them to turn completely white.
This phenomenon is called coral bleaching.

The pale white colour is of the translucent tissues of calcium carbonate which are visible due to the loss of pigment producing zooxanthellae.
Corals can recover if the stress-caused bleaching is not severe.
Coral bleaching has occurred in the Caribbean, Indian, and Pacific oceans on a regular basis.

CAUSES
Increase in temperature
Ocean acidification- oceans absorb more carbon dioxide
Solar radiation and ultraviolet radiation - changes weather patterns
Infectious diseases caused by bacteria. Affect the photosynthesis
Increased sedimentation
Overfishing and pollution from agricultural run-off Coral mining

EFFECTS
Fish rely on coral for food and shelter
Decline in genetic species decline in diversity
Healthy corals attract touristsCauses large shift in fish communities
Protect coastlines by absorbing wave energy

101
Q

What is the way forward to tackle coral bleaching

A

Halting unplanned coastal development
Sustainable fishing
Minimising chemical enhanced fertilisers and pesticides
Treating harmful industrial waste
Tackling climate change and global warming

102
Q

What initiatives have been taken to protect the corals

A

Initiatives to Protect Corals :
A number of global initiatives are being taken to address the issues, like:

  1. International Coral Reef Initiative
  2. Global Coral Reef Monitoring Network (GCRMN)
  3. Global Coral Reef Alliance (GCRA)
  4. The Global Coral Reef R&D Accelerator PlatformSimilarly, the Ministry of Environment and Forests and Climate Change (MoEF&CC), India has included the studies on coral reefs under the Coastal Zone Studies (CZS).

In India, the Zoological Survey of India (ZSI), with help from Gujarat’s forest department, is attempting a process to restore coral reefs using “biorock” or mineral accretion technology.

National Coastal Mission Programme, to protect and sustain coral reefs in the country.

103
Q

Why are coral reefs found in clear tropical waters only

A

Coral reef is independent ecosystem.

Coral reef consists of polyps and algae.

Both unicellular algae and filamentous algae are present in polyps.
In dead skeleton of coral there is filamentous algae.
While unicellular algae is in the body of polyps.
The polyp releases carbon dioxide . The carbon dioxide is used by algae .
The complete recycling of matter takes place in corals.
For photosynthesis of algae it needs light and clear water.

104
Q

What is a Watermass

A

body of ocean water with a distinctive narrow range of temperature and salinity and a particular density resulting from these two parameters.

105
Q

What are dead zones

A

Also called hypoxic zones
Hypoxic zones are oxygen-starved areas in the ocean or lakes are areas where very few or no organism survive.
The regions facing such a situation essentially become biological desert.

106
Q

What are the causes of dead zones

A

Natural Cause:
In the summer, northerly summer winds work together with the Earth’s rotation to push oxygenated surface water offshore and this coastal water is replaced by low-oxygen but nutrient-rich waters from the depths of the continental shelf by a process known as upwelling.
Once this nutrient-rich water reaches the ocean’s sunlit layers, it fertilizes blooms of phytoplankton.

Eutrophication i.e the process by which extra nutrients are added to the water bodies, stimulating an overgrowth of algae, which then sinks and decomposes in the water.
The decomposition process consumes oxygen and depletes the supply available to healthy marine life

Extra nutrients are added due to fertiliser , domestic and sewage , industries and burning of fossil fuels
Global warming increases temperature and affects flowing manner and lowers the solubility of oxygen

107
Q

What is the effect of dead zones

A

Nutrient over-enrichment -behavioral and physiological impacts including reduction in fitness or reproductive capacity, increased mortality and migration.

Increases the metabolism of marine animals.Low oxygen level kills coral reefs.
Elevated nutrient levels and algal blooms can also cause problems in drinking water in communities nearby and upstream from dead zones.

Harmful algal blooms release toxins that contaminate drinking water, causing illness in animals and humans.

Threatened global food supply and fisheries.

Economic Loss due to reduction in potential for commercial fishing.

108
Q

What are the factors responsible for oceanic salinity variation

A

Evaporation rate:
Oceans between 20 to 30 degree North and south have high salinity because of
(1) high temperature
(2) low humidity .
Temperate oceans have lower salinity due to lower temperature.

Amount of Fresh water added in ocean:
Equatorial waters have lower salinity due to heavy rainfall and high humidity.
Oceans fed by large rivers like Amazon, Congo, Ganges, Mekong etc have lower salinity.
Melting of icebergs and resultant fresh water intake into Baltic, Arctic and Antarctic ocean waters makes them less saline. Thus, global warming and greenhouse gas effect has indirectly affects the salinity levels of the oceans.

Currents Mixing:In open oceans, currents mix and flow freely, hence salinity is average 35ppt or lower.
Whereas in the Caspian sea, Mediterranean sea, Red sea and other wholly / partially enclosed seas – the fresh water doesn’t mix freely with ocean water hence salinity is higher.

Salinity, temperature and density of water are interrelated. Hence, any change in the temperature or density influences the salinity of an area.

109
Q

What are the effects of salinity variation

A

cold water at the poles sinks and slowly moves towards the equator and warm-water moves the cold water at the poles sinks and slowly moves towards the equator and warm-water moves from equator to poles to replace the sinking cold water.

Thus salinity has a great role to play in the formation and circulation of oceanic currents via the thermohaline process.

temperature and rainfall is affected by currents, the level of salinity has indirect role in Earth’s overall climate.

without salt more of the oceans would freeze during winter- affecting the movements of both fish-schools and cargo ships.

objects that might sink in freshwater are able to float in seawater. This has a big effect on life in the sea

Despite having no fins, the plankton are kept perpetually afloat due to the density of seawater.

Without plankton, entire marine ecosystem will collapse

110
Q

What are the uses of lakes

A
  1. Transports - Great lake waterways
  2. Farms + industry
  3. Storage
  4. Hydro electric- hirakund lakes
  5. Agriculture of dams on artificial lakes- Bhakra Nangal @ gobindsagar
  6. Moderation of climate land and sea breeze
  7. Minerals rock salts borax
  8. Tourist attraction
111
Q

What are the criteria to declare that the onset of monsoon has started

A
  1. Rain-bearing westerlies being at a minimum depth and speed.
  2. At least 60% of the available 14 stations in Kerala and coastal Karnataka reporting rainfall of 2.5 mm or
    more for two consecutive days after May 10.
  3. A certain degree of clouding, indicated by a parameter called ‘outgoing longwave radiation’ (OLR),
    being below 200 W/square metre.
112
Q

What is onset of monsoon

A

The burst of the monsoon is known as the beginning of the onset of the monsoon and is a phenomenon that involves the sudden changes in the weather conditions and is a characterized by the dry an the wet.

Geography 🌍 (6 decks)

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