Climatology part 1 Flashcards
What is atmosphere
A thick gaseous envelope which surrounds the earth from all sides and which is attached to the surface of earth by gravitational force
What is the importance of atmosphere
- Provides all necessary gases for sustainance of life
- No life if no atmosphere
- Doesn’t allow harmful uv radiations to reach earth surface
Height of atmosphere
It’s between 16000km to 29,000 km from earth surface,
But 97% of atmosphere is in 30kms and 50% of atmosphere is in 5km
Composition of atmosphere
Water vapour , gases , particulate matter
Gases in the atmosphere and there composition
99% of atmosphere is made up of two gases
1. Oxygen 78%
2. Nitrogen 21%
Other 1% have co2 (0.03%), Argon (0.93%), Neon (0.02%)
0.005 % of helium, xenon,krypton, hydrogen.
C02 have special property in receiving and sending out the radiation what is it
It is transparent to incoming radiation while opaque to out going radiation. Due to this property it heats up the lower atmosphere
What is water vapour
It’s the amount of humidity in the atmosphere
Amount of water vapour changes in atmosphere in what basis
Height : 90% water vapour in just 5km
Season :more moisture during summer
Latitudes : it decreases as we go up to the poles
Importance of water vapour
Acts like a greenhouse gas, so it helps in heating of the atmosphere at lower surface
Responsible for condensation (fog and clouds),precipitation (rainfall )
Particulate matter includes what ? And there importance in atmosphere
Particulate matter implies smoke,ash, pollen grains, dust, salts, etc
Importance
1. They act as an hydroscopic nuclei in which watervapour condenses to form cloud.
2. The artificial rainfall which are due to sprinkling of iodide/salt in to the atmosphere for the formation of the hydroscopic nuclei
Hydroscopic nuclei is responsible for
Maintaining watervapour as clouds in the atmosphere
Different layers of atmosphere
Exosphere, ionosphere, Mesosphere, stratosphere, troposphere
Mixing of different gases occur in which layer of atmosphere
Troposphere-zone of mixing of air
All weather phenomenon occurs in which layer
Troposphere
Clouds are present in which layer
Troposphere
In which layer temp decreases with increase in height
Troposphere here the temp decrease at a rate of 6.5 degree celcius per kilometer
Height of troposphere
8-9km in poles, 16 kilometers on equator.
So poles x2 we get the distance of the equator
Tropopause mane Kya hai
Troposphere ends and stratosphere starts this is called tropopause,
As the height is more in equator so temp Is a bit low in tropopause than at the poles, as in troposphere 6.5 degree celcius decrease is seen with increase in km height
The place where zone of mixing of air stops
Tropopause
Layer from 20 km to 50km
Stratosphere, it is next to troposphere
The high clouds present in stratosphere are called
CIRRUS CLOUDS
OZONE is present in ?>
Lower layer of stratosphere
What’s the job of ozone
It protects the earth from harmful UV Radiation.
So the temp increases or decreases when we go above the stratosphere
The temp increases due to the presence of ozone.
The end of stratosphere is called
Stratopause
Layer between 50km to 80km is called and is present where
Mesosphere is present above stratosphere
Temp quality or characteristics in meso sphere
In mesosphere the temp goes on decreasing with increase in height and it goes to around -80 degrees centigrade at 80 kilometer height
What is thermosphere
It is above mesosphere
And classified into two types ionosphere and exosphere
and temp increases with increase in height
Ionosphere qualities
It is between 80km-640km But it got divided into 4 sub layer known as D layer - 80 - 99 km; E layer - 99 - 130 km; F layer - 130 - 380 km; G layer - 380 - 640 km;
Range of Dlayer
80-99 km
Range of E layer
99-130 km
range of F layer
130-380 km
Range of G layer
380-640 km
Operations of D layer
It reflects low frequency radio waves
Operation of other layers excluding D layer
They reflect medium and high frequency radio waves.
Montreal protocol is on
Substances that deplete O3 layer
F layer is also called
Apleton layer
E layer is also called
Kenny heviside layer
What is insolation
INcident SOlar radiaTION is called insolation
Mechanism in solar energy
When hydrogen is converted to helium, through the process of nuclear fusion, we get the interior of the sun releasing large amount of energy
What is solar constant
It’s the amount of insolation reaching the earth surface from the sun, it is around 2cal/cm2/min
What is Wien’s displacement law ?
It states that the wavelength increases when the temperature of the insolating body decreases
Very high temperature implies what as per wien’s displacement law
High temperature implies short waves
Terrestrial radiation or earth radiation have what waves
Earth radiation have long waves, i.e low energy waves
What is greenhouse gas effect
Trapping of long waves Is called greenhouse gas effect
The earth is divided into 3 zones as per latitudes and amount of insolation it receives
3 layers are
- Tropics
- Temperate
- Polar
What is perihelion and aphelion
Perihelion is on jan 3 and aphelion is on July 4
Why is sky-> blue in colour
Because the atmosphere scatters the sun rays , i.e 23% of the Sunrays gets scattered,and the blue light is the most scattered of all during day time and red is the most scattered of all during early mornings and evening
Other two operations rather than Scattering of sun rays by atmosphere are ?
Absorption and reflection
How much amount of sunrays are absorbed by the atmosphere
14%
Sunrays getting reflected is called
Albedo
Out of 100% of the heat received by earths from sun how much is scattered
35% is scattered and 27% is by clouds and 6% is by dust particles and 2% is by snow
How much % of sun radiation is reflected or scattered by clouds and snow
27% by cloud and 2 % by snow
65% gets un scattered, how much is absorbed by the atmosphere
14% is absorbed by the atmosphere, and 51 % is absorbed by the earth surface
Direct radiation received by the earth
Earth gets 51 % of radiation in. That direct holds 34% and 17% by the diffused light
Refer albedo once
Yup, else you wont get first rank
There are three types of heating of earth
Conduction, convection, radiation.
what is conduction by the atmosphere
- Transfer of heat by molecules
- Touching of bodies of different temperatures.
- > metals are the good conductor of heat so heat transfer is possible to only ground layers of the atmosphere
Explain about radiation
Transfer or heat by no medium.
Solar radiation heats up to the ground, terrestrial radiation heats up the atmosphere
What is convection
Transfer of heat through the movement of mass of a substance.
Effective in fluids
Seen in cyclones
What sort of heat transfer is seen in cyclone
Convection
Which air has high humidity holding capacity hot or cold
Hot air has high humidity holding capacity and cold air have comparatively less humidity holding capacity
How are clouds formed
If you have said just by evaporation slap your self you fool!!
Due to convection the warm air becomes lighter and rises upwards and forms clouds at the hygroscopic nuclei
Low preassure is associated with rainfall or dryness
Low pressure implies high rainfall
High pressure implies what rainfall or dryness
High pressure implies dryness
Factors affecting distribution of temperature
- Latitudes
- Altitudes
- Distance from the coast
- Difference between nature of land and water
- Nature of ground water
- Nature of ground slope
- Winds
- Ocean currents
How do latitudes affect the temperature
Temp decreases as we go away from the equator or gets nearer to the poles
Large amount of temperature is not on the equator but on 5N or 5S why
As the equatorial regions gets cloud cover and max rainfall everyday,so the temperatures are comparatively Low in equatorial than at 5N or 5S
How does altitude affect the distribution of temperature
Normal lapse rate -> 6.5*C as we increase the altitude by 1 km till 16-20kms, as maximum amount of water vapour is present in the lower atmosphere so the heat Is more at the ground as we move up it gets gradually decreased.
What is normal lapse rate
The increase in temperature 6.5*C with increase in 1 kilometer above the ground is called normal lapse rate
How does the coast affect the distribution of temperature
As the air moves from low pressure to high pressure and pressure is inversely proportional to temperature, we have low pressure at the land,
so the wind blow from sea to land at day (on shore winds)
And the wind blows from land to sea at night ( off shore winds)
What are offshore winds
The winds that blow from land to sea are known as offshore winds
Why do coastal cities have moderate temperatures
Due to the daily rhythms of winds flow from land to sea and from sea to land, due to this effect absent in continental interiors so they have extreme climates
I.e hot summers and cold winters
What is meant by continentality
The continental interiors expose to extreme temperatures
I.e high temperatures at summer and lower temperatures at winter
How does difference of nature of land and water affect distribution of temperature
Land heats up quickly and water heats up slowly
Because
1. Land gets the heats to go up to 3mts depth where as water gets 200mts depth of heat,
2. During night time land gets cooled faster than water.
3. Specific heat of water is more than land.
4. Water gets heat redistributed due to waves and ocean currents, but land doesn’t do any distribution
5. Albedo -> water gets more sun insolation to get reflected than Land
How do the nature of ground surface affect distribution of temperature
As
- Black cotton soil absorbs More heat than other soils
- Sand takes more than half amount of heat it receives ie around 66% and the rest is reflected
- Open forest takes only 33% of heat And reflectes the rest.
- Snow doesn’t care about heat
More and low amount of insolation takes place in which kind of soils
Black cotton soil and snow
How do nature of ground slope affect distribution of temperature
Slope which faces the sun receives more insolation,
Eg: in Himalayas the southern slope gets more insolation, so do the vegetation and human settlement compared to northern slope.
What are isotherms
The line on the map connecting the points having the equal or same temperature at a given time or average time period is called isotherms
Isotherms are distributed horizontally or vertically, use brain
Horizontal distribution of temperatures have isotherms because the horizontal have latitudes so do the equal temperatures
Isotherms are irregular and closely spaced in which hemisphere and why ?
Closely spaced in northern hemisphere and it is due to dominance of land
Isotherms takes actual temperature of the place or some other temp, if some other explain what it is
Isotherms take the temp when it is reduced to sea level.
Isotherms are regular and parallelly placed to latitudes in which hemisphere
Southern Hemisphere due to the domination by water
isotherms while going from land to sea, deviate towards poles in which season
Winter
isotherms while going from land to sea, deviate towards equator in which season
Summer
isotherms while going from sea to land, deviate towards poles in which season
Summer
isotherms while going from sea to land, deviate towards equator in which season
Winter
Mt. Kilimanjaro though present on equator have ice cap why
Because of the normal lapse rate and its height
What is tropical zone, list out it’s characteristics
Tropical zone extends between 22.5N to 22.5S
The equatorial region experience the vertical sunrays during equinox i.e twice a year.
So the area between the Tropic of Cancer And Tropic of Capricorn receives twice the direct sunlight in a year,
Due to tilting of earth
What are temperate zones describe them
Temperate zones expands from 23.5N/S to 66.5N/S,
Temperate zone never gets direct sunlight.
what is a frigid zone
The zones above 66.5N/S to 90N/S is called frigid zone.
How does frigid zone have days and nights
6 months days and 6 months night in frigid zones
