Climatology Part 2 Flashcards
What is inversion of temperature
The increase in temperature with increase in altitude is called inversion of temperature
Increase in temperature with increase in altitude is called
Inversion of temperature
Inversion of temperature is also called
Negative lapse rate
Types of Temperature inversion
Advectional inversion, non advectional inversion.
advectional inversion deals with
Air movements and examples are
- Cyclonic inversion
- Valley inversion
cyclonic inversion comes under
Advectional inversion
Non advectional inversion has air movement or not
Little to NO air movement in advectional inversion
Describe about Non Advectional inversion
It is also known as ground inversion,
Occurs on earth surface due to radiation mechanism,
During winter air on the ground is cold and the air above is warm, due to non advectional inversion we experience FOG.
Fog is seen in advectional or non advectional inversion
Fog is seen in non advectional inversion, because
The cold air on the ground and hot air above the ground helps for the formation of fog
Conditons for non advectional inversion
- Long winter nights
- Cloudless and clear sky
- Slow or no movement of air
What happens in the long winter nights, why Is it required for NON-advectional inversion
As the nights are longer so loss of heat exceeds the gain due to insolation at day time
Cloudless and clear sky, what’s its influence on the NON Advectional inversion
Presence of dry air near the surface makes the heat absorption zero, if the clouds and rain occurs we can see the air moist and it absorbs heat,
So the non advectional radiation needs the dry air
Slow or no moment of air, why is it necessary for non-advectional inversion
So that intermixing of air is avoided
What kind of cyclones are seen in advectional inversion
Temperate cyclones are seen here, because of the fact that the cool polar Winds and warm westerly winds meet.
They form a front i.e cool air goes below the hot air
Temperate regions gets cyclones, what winds causes this
Cold polar winds and warm westerlies Causes fronts, leading to cyclones
What happens in valley inversion I.e valley advectional inversion
Here the upper parts of the valley i.e the peaks of the hills gets heat lost more than the valley regions,
So the cold air above the valley gets down to the warm air( because cold air is heavier than warm air),
Thus temperature inversion is seen
Why do people don’t cultivate in valleys and prefer to cultivate on hill tops
As due to advectional inversion there forms frost on the valley floors, which is harmful for the agriculture so people generally adopt for the top areas
What is photo chemical fog
It is formed due to the combination of photo (Sun) + chemical (small particles) + Fog ( temperature inversion)
We came to know that fog or frost is not beneficial to the crops, but some crops do grow wha are they
Coffee and mocha in Yemen
Differnence between frost and front
Front causes cyclone where as frost causes FOG
What is air pressure
It is also called as barometric pressure
Total weight of mass of column of air per unit area at sea level
Average air pressure is
1013 milli bar
Isobars what are they
Line which join the places of equal pressure is called iso bars
What happens in high pressure
Low temperature forms and
no rai fall and
mostly we see subsidence or downwards force of air
Mostly seen in WINTER season, clear sky,
Aridity and no precipitation,
Promotes stability in the atmosphere
What happens in low pressure
The air raises upwards,
High temperature,
Good for rainfall
What promotes stability in the atmosphere high or low pressure
High pressure promotes stability in the atmosphere
Why do we listen to the person who is very far way in winters
Due to high pressure the air gets subsistence i.e downward, so the air is more denser,as the sound waves travel fast and clear in solids, so we can hear the person from a very long distance in winters
How is the horizontal distribution of air pressure
Horizontal distribution is generally characterised by thermally created ( constant ), created due to rotation of the earth (DYNAMICALLY CREATED).
We see that air goes up ( low pressure ) in equator and air comes down ( high preassure at the poles)
And in between due to dynamic i.e rotation of the earth we can see the air going down at 30-35N/S (High pressure )
And air going up in 60-65N/S (Low pressure)
How is wind movement at poles and 30-35*N/S latitudes
The wind goes down(High Pressure) at poles and 30-35 N/S (sub tropical) , at poles it is due to thermal and at 30-35N/S (sub tropical) it is due to earth rotation.
How is the wind direction at equator and 60-65*N/S, Up or Down
We have a low pressure at the both points, with wind moving upwards,
At equator due to Thermal action and
At 60-65*N/S due to Earth rotation (Dynamically formed )
Preassure belts are regular in which hemisphere
Southern Hemisphere and irregular in northern hemisphere because of unequal distribution of land and water
What are known as DOLD-DRUMS
The weak winds in the equatorial Low, makes it called as belt of calm or dold-drums
What are called HORSE LATITUDES
There are very calm conditions here, weak wind system, seen in subtropical high,
Here we have anticyclonic condition with arid climates,
We have deserts in these regions on the west side of the continents
Which region have deserts on the west side of the continent
Sub tropical high have arid climate and anti-cyclonic conditions,
Here calm com dictions ans weak wind system making it HORSE LATITUDES
What zone is also called as frontal zone
Sub polar low
Cold polar winds and warm westerlies result in fronts in which region
Sub polar low, so we call these regions as frontal regions
All pressure belt shift northwards or southward due to movement of sun northward or southward, except what
Polar High, except it all other regions move as per sun movemnt
In summer and winter and equinox, all polar belts move in which direction
In summer polar belts move north,
In winter polar belts move south,
In equinox they remain same
Why do wind changes its direction
Due to Coriolis force
What is wind ?>
Air in motion is called wind
The horizontal air motion is affected by 3 forces they are
- Pressure gradient force.
- Frictional force.
- Coriolis force
What is pressure gradient force
The rate of change of pressure is called pressure gradient.
Isobars when they are near to each other indicates high pressure gradient
Higher is the pressure gradient higher is the wind velocity
What is frictional force in winds
It is due to the friction between wind and earth surface, it is low above the earth
Coriolis force what is that
The force caused due to rotation of earth on its own axis is called coriolis force.
Coriolis force is minimum at where and why
It is minimum at equator due to the rotational speed is maximum at the equator
Coriolis force is major at where
It is major at poles, due to low rotational speed
What is the deflection of wind in coriolis force (w.r.t speed)
High speed, high chance of deflection.
Winds are classified into three types name them
- Permanent winds,
- Seasonal winds,
- Local winds
What are permanent winds
Winds that blow in same direction throughout the year are called permanent winds,
Example : westerlies, polar easterlies, trade winds or easterlies
What are trade winds
Winds that blow near equator are called trade winds, they are also known as easterlies
What is inter tropical convergence zone
The winds that converge near the equator i.e two easterlies from north and south is called inter tropical convergence zone
Define trade winds and which side do they bring rainfall on earth, and why are they called so
Winds that blow from subtropical high pressure to tropical low pressure are called trade winds,
They are easterlies, they give rainfall on east side of the continent because they blow on shore.
These are called trade winds because olden days sailors use it
ITCZ shifts with movement of sun or not
Yes it shifts with the movement of sun, when sun movie north wards it moves north wards and when the sun moves south ward it moves southward
What plays a very imp role in Indian monsoons, regarding winds
Inter tropical conversion zone
What are horse latitudes
Dynamically induced high pressure belts due to subsidence of an air is called horse latitudes, we find them at sub tropical zones
From where do trade winds and westerlies emerges
Horse latitudes or subtropical highs
What deserts lie on horse latitudes
Hot deserts lie on horse latitudes
What are westerlies
They blow from horse altitude to frontal zones
What do westerlies gives arid climate or precipitation based
Westerlies blow onshore giving precipitation through out the year
Where do we see westerlies
We see them on the north west of Europe and America
Because of lack of land on southern side, westerlies blow at a high phase naming 40* , 50, 60 with a name
The 40* are called as roaring forties,
50* are called as furious fifties,
60* is known as shrieking sixties
What are polar easterlies
These blow from polar north/south to the frontal zones in east to west direction, so they are called sub polar easterlies
What is shifting of pressure belts concept
All the pressure belts move northward/ southward along the northward/ southward movements of the sun,
Except polar high pressure belt
When do the shifting pressure belts occupy there normal position
On equinox i.e march 21 and sept 22
Summer solstice June 21 and winter solstice dec 22
What are the possible type of climates due to shifting of belts
Mediterranean type of climate and
Monsoon type of climate
What is Mediterranean type of climate
These climates have winter rains and dry summers,
Plants grow in shrubs in spring in Mediterranean climate
Monsoon type of climate
Here we can see complete reversal of winds
ITCZ which is present on the equator moves towards the Tropic of Cancer in summer solstice (June 21)
So it attracts the low pressure thus monsoon i.e north east monsoon and when the winter solstice comes again it attracts the high pressure thus reversal of monsoon
What are dural winds
Lands and sea breeze complete cycle of diurnal winds
What are dry winds land breezes or sea breezes
Land breezes are dry and sea breezes are moist
When do we see mountain breeze
During night time valley get heat preserved and mountain heat is lost at maximum rate forming the mountain breeze
Westerlies have land breezes or sea breezes
Sea breezes
What happens when the mountains are present in the sea breezes area
The mountains makes the air go up and from the clouds, forming rain on the wind ward side and no rain on the lee ward side
Why do Mumbai receive rainfall where as Pune receive less rainfall
Because Mumbai is on the wind ward side of western ghats and Pune is on the leeward side of western ghats
Why do ice or snow melt in North America, what is chinook
The dry winds makes windward side on the Rocky Mountains making it go up and have rainfall, on the windward side.
This makes zero rainfall on the leeward side thus. The snow melts due to chinook.
Chinook is a condition in North America to make the snow melt
What is foehn ?
Foehn is seen in the alps Region of Europe, this have the Same property of the chinook, it makes the Switzerland warm during winter too, so the northern winds help the Switzerland to have a good climate in the winter, making the possibility of the tourism.
What are harmattan/doctor winds
These are warm,dry, dusty winds. Which originate in Sahara desert.
These winds blow towards the western coast of Africa,
the western coast of Africa hot and humid through out the year;
with the arrival of extremely dry harmattan the humidity in the Region gets reduced and makes the settlement comfortable.
Thus harmattan are also known as doctor winds.
What is sirocco/ blood rain
Warm,dry and dusty winds which originate in Sahara desert and flow towards Southern Europe.
These winds act as onshore winds to the southern parts of Europe, so rains in Europe.
As the wind is from Sahara, so rain also gets the soil particles making it red colour, so we call it blood rain.
Sirocco is harmful to agriculture and horticultural crops.
What is called blood rain
Sirocco
What is mistral
Cold and dry winds blowing from north to south in Europe i.e from the alps to Mediterranean Sea. Thus making the wind cold, so people in Europe avoids north facing of houses
what is bora
Bora is associated with precipitation of Italy, unlike mistral bora picks up moisture from Adriatic Sea.
This makes the cold and dry mistral to convert to cold and humid bora.
Thus Italy gets rainfall
What is blizzard
The violent,stormy,dusty and powdery wind blowing with very high velocity
It originate from permafrost of Siberia
Visibility and temperature is decreased with the arrival of these winds
What is 3 cell model of winds
The 3 cells are
- Topical cell.
- Mid latitude cell,
- Polar cell.
What is a Tropical cell
Trade winds on the surface bow from STHPB to EQLPB
These winds after reaching EQLPB rises up due to heat and diverge upwards, forming
ANTI TRADE WINDS.
The tropical now settles down at STHPB forming one cycle of tropical or hardley cell
What is hardley cell
The completion of trade winds i.e trade and anti trade winds combined called as hardley cell
What is mid latitude cell
Surface we have westerlies and above surface we have anti westerlies, forming a circle known as mid latitude cell or Ferrell cell
What is Ferrell cell
It’s the mid latitude cell
What is a polar cell
Polar easterlies on surface and anti direction on the top making the cell, i.e polar cell
What are jet streams
The strong circumpolar upper air circulation,
Which generally flows from west to east in upper portion of troposphere between two air masses of different temperature is known as jet streams.
What are characteristics of jet stream
They are present at the tropopause,
These are rivers of wind having speed of around 160km/hr or some times 400km/hr
They measure hundreds of kms in width and have a depth or 2-3 kms
What are rossby waves
These are the jet streams, which moves in a wavy fashion, named as rossby waves
Jet streams are stronger in which season winter or summer
They are stronger in winter than in summer
What are four types of jet streams
- Polar front jet streams
- Subtropical westerly jet stream.
- Polar night jet stream.
- Subtropical easterly jet stream.
What are polar front jet streams
These are developed in frontal zone, i.e SPLPB,
Because of the convergence of cold polar air mass and warm subtropical air mass
What is the direction of polar front jet stream
West to east
What are sub tropical westerly jet streams
They are developed in upper troposphere, between hardley cell and mid latitude cell
What are the directions of subtropical westerly jet streams
They are from west to east
What is subtropical easterly jet stream
It is happened in upper troposphere and between India and Africa, because of intense heating of Tibetan plateau during summers
What is the reason fro sub tropical eastern jet streams
They are formed due to heating of Tibetan plateau
What is the direction on sub tropical easterly jet streams
East to west
What are polar night jet streams
These are also known as stratospheric jet streams, develops during winter
What are the uses of subtropical western jet streams in Indian context
They help in melting of Himalayas and also helps in causing rain fall —> imp for Rabi crops
What are the uses of subtropical easterly jet streams
They are useful to send the north east monsoons into the country, so the rain fall gets all over the country
What are the disadvantages of polar night jet streams
They raise the pollutants from the troposphere to stratosphere, causing a hole in ozone
How do jet streams affect aviation industry
They help in saving fuel if the direction is same, else the planes try to travel another area, If the direction. Is opposite
What is called sublimation
The direct conversion of solid to gaseous form is called sublimation
What is humidity
Amount of water vapour in parcel of a air
What is latent heat of vapourization
The temperature at which water starts evaporating is called latent heat of vapourization.
About 600 calories are required for converting 1 gram of water to vapour
Why do we feel hot in cloudy day
As the latent heat of evaporation now gets cooled by realising the heat out side in the form of latent heat of condensation. So we feel hot
Which have high potential energy ice or water or watervapour
Potential energy is High for water vapour than the ice.
Types of humidity
- Humidity capacity
- Absolute humidity
- Relative humidity
What is humidity capacity
It is the moisture holding capacity.
I.e the capacity of the air of certain volume and certain temperature to retain maximum amount of moisture
What’s the effect of humidity capacity with temperature
As temperature increases —> Humidity capacity increases
When is the humidity capacity higher summer or winter
In summer humidity capacity is higher
What is absolute humidity
It refers to the actual amount of water vapour in parcel of air
What is relative humidity
It is the ratio of amount of water vapour actually present to its maximum capacity
I.e ratio of absolute humidity to humidity capacity
What is called saturated air
Air having 100% relative humidity is called saturated air
I.e when air possesses the maximum amount of water vapour it can retain
When do condensation starts as per actual and humidity capacity concept
Condensation starts when the relative humidity is more than 100%
When is the air called super saturated
When the air have relative humidity more than 100%, i.e when it starts to condense
When do the air get supersaturated
As we have seen air get saturated in 2 cases
- When moisture is further added (practically not possible),
- When temperature is reduced, so that the air moisture holding capacity drops i.e humidity capacity drops and water in the absolute humidity gets more
The temperature at which we get relative humidity 100% is called
Dew point
Temp at which relative humidity is 100 % is called
Dew point
What is the importance of relative humidity , where do we apply it
Used by meteorologist to determine the possibility of rainfall,
High relative humidity and low relative humidity which isn favourable for settlement
Both are not favourable for settlement
What is adiabatic change of temperature
It involves change of temperature due to expansion and compression
What happens when the air descending from top
It gets heated
When happens when the air ascends
Then the air starts cooling
What is dry adiabatic lapse rate
The decrease in temperature as air goes up i.e 10*C per 1 Km
What is wet adiabatic lapse rate
It is the decrease in temp when we further ascend the air, after condensation, it is around 5*C per Km
What’s the difference between environmental and adiabatic lapse rate
The environmental lapse rate refers to the temperature drop with increasing altitude in the troposphere;
that is the temperature of the environment at different altitudes.
It implies no air movement.
Adiabatic cooling is associated only with ascending air, which cools by expansion.
Instability of air with respect to adiabatic is when
Instability of air is seen when normal lapse rate Is greater than dry adiabatic lapse rate
What happens when instability of air increases
It causes rain fall
What is fog
A special type of cloud very near to the ground,
Which contains microscopic droplets of water, which are kept in suspension in air is known as fog.
How is fog formed
Fog is formed when the cool air is below warm air, i.e by temperature inversion
Types of fogs
- Radiation fog
2. Advectional fog
What is radiational fog
During winter —>surface is cool and the air coming in contact with the surface gets condensed and forms fog
What are the conditions required for radiation fog
- Winter nights should be long and cold,
- Cloudless and clear sky ,
- No movement of air
- Less moisture
What is advectional fog
Advectional fog is of three types
- Sea fog
- Valley fog
- Frontal fog
What is sea fog
Found in regions of mixing up of hot and cold ocean currents,
Very dense fog
Examples of sea fog
- New found land and Grand Banks —> mixing of cold Labrador and warm Gulf Stream.
What is valley fog
This is due to temperature inversion
What is frontal fog
Due to the convergence of warm and cold air masses, seen in SPLPB
What are some of the effects of fog
It hinders navigation, and disturb transport system.
Smoke + Fog formation of smog
Photo chemical smog.
What are the effects of photo chemical fog
Due to the burning of fossil fuels —> we get NO2 + VOC (volatile organic compounds), these when reacted to sunlight forms ozone, so we get
Proxy-acetyl-nitrate (PAN) and ozone which. Are dangerous for our body
