Everyday Weather Flashcards
Define: tropopause
The boundary between the troposphere and the stratosphere.
Define: troposphere
The bottom most layer of the atmosphere. Where all weather occurs.
Define: stratopause
The boundary between the stratosphere and the mesosphere.
Define: stratosphere
The zone of the atmosphere above the troposphere. It is characterised initially by isothermal conditions and then followed by a gradual rise the temperature. Most of the atmospheric ozone is located here.
Define: insolation
Insolation is a measure of ‘solar radiation energy’ received on a given surface, at a given time.
Explain the importance of the various elements in the atmosphere.
Elements are very important. Water vapour, more vapour generally means warmer temperatures, and it also means more chance of weather (clouds +rain). Carbon Dioxide (CO2), absorbs terrestrial radiation and is absorbed by oceans and plants. Greenhouse effect involves a warming of the Earth. Ozone (O3), found in the upper levels of the stratosphere and the lower part of the mesosphere. Absorbs 60% of ultra-violent light from the sun. Ozone particles essentially fill up, and sink to lower levels of the stratosphere. Holes in Ozone like over NZ believed to be caused by man.
With respect to the tropopause: explain why the altitude of the tropopause varies with latitude;
The tropopause is highest over the equator where its temperature is coldest. The tropopause is lowest over the poles where the temperature is warmest. The tropopause height varies in mid latitudes, its temperature is warmer then over the equator but colder than the poles.
What is an isothermal layer?
An isothermal layer is when temperature remains constant with gain in height.
What is an inversion?
An inversion is when temperature increases with height gained.
What is the percentages of Gases in the atmosphere?
Nitrogen = 78% Oxygen = 21% Argon, Carbon Dioxide, Neon, Helium, Hydrogen, Ozone, Other = 1%
How much of the Atmosphere molecular mass is located within the Troposphere?
75%
Which layer of the atmosphere absorbs the incoming radiation from the sun …..
the ozone layer
The isothermal layer has a ….. temperature
constant
The layer of atmosphere in which most convection takes place is the …..
troposphere
Mid-latitude cell = high/low pressure
high
beyond the ozone layer the temperature …..
reduces
The tropopause varies in height from ….. at the equator to ….. at the poles
18km at the equator and 8km at the poles
Polar cell = high/low pressure
low
The ozone layer is almost as ….. as the surface
warm
Temperature drops by ….. degrees per ….. feet
20 every 1000ft
When compared with the size of the earth, the troposphere is very thick/thin
thin
What clouds can penetrate beyond the tropopause …..
cumulus congestus and cumulonimbus
The ITCZ is …..
the region where the surface air flow from each hemisphere converges and rises
There is very little convection in the stratosphere becuase …..
the air at the top of the layer is warmer than the air at the bottom
The sub polar low occurs between …..
the polar cell and the mid-latitude cell
Draw the vertical movement of air with your minds eye
Tropical Cell
Mid-Latitude Cell
Polar Cell
In rising air surface pressure …..
falls
Temperatures at the ozone layer …..
increase
Equatorial trough = high/low pressure
low
What degree latitude do Polar Easterlies blow
from the poles to 60˚ latitude.
The degree latitude do Prevailing Westerlies blow
from 60˚ to 30˚ latitude.
The degree latitude Trade Winds blow
from 30˚ latitude to the equator.
Global scale winds are winds that are created in what Global circulation Cells.
Polar Easterlies
Prevailing Westerlies
Trade Winds
Describe mountain/valley winds.
During the day, mountains warm, causing the air over them to be warmer than the air over the valley at the same elevation. Warming the air causes it to rise up, creating a valley wind. During the evening, the air cools due to a loss of surface energy to space. The cool dense air moves down slope as a mountain wind.
Describe Chinook winds.
A Chinook wind is a warm dry wind on the leeward side of a mountain. As air descends the leeward side of a mountain, it is compressed and adiabatically heated. Warming the air causes the saturation point to increase, causing a decrease in its relative humidity. The new warm and dry wind moves down slope rapidly, and during the spring causes substantial melting of mountain snow.
Describe Santa Anna winds.
Santa Ana winds are warm and dry winds. Over plateau regions in the desert region of the United States, high pressure pushes the air off the plateaus, forcing the air into narrow mountain valleys. As the air is forced through the valley it compresses and warms. As the air warms the saturation point rises and its relative humidity drops.
What are the main sources of Earth’s energy budget and how much do they energy do they produce?
(99.98%) is from solar radiation.
.013% comes from geothermal energy that is created by the radioactive decay of Earth’s core.
.002% of Earth’s incoming energy comes from the action of tides caused by the interaction of Earth with the Sun and Moon.
Waste heat energy from fossil fuel consumption accounts for about .007% of Earth’s Energy Budget.
What is ‘albedo’?
the proportion of the incident light or radiation that is reflected by a surface typically that of a planet or moon
What is the average albedo on Earth?
The Earth has an average albedo of about 30% which means that ~30% of incoming solar radiation is radiated back into space before it reaches Earth’s surface.
What are the major albedo sources and how many percent of energy do they reflect back?
30% absorbed befor reaching surface
the atmosphere absorbs 19% and the
earth’s surface absorbs 51%.
How much solar energy is reradiated as infrared energy?
Around 70% of solar energy that is absorbed by the Earth is reradiated as infrared energy.
How is the Earth’s Energy Budget in equilibrium?
The Earth’s Energy Budget is in equilibrium as the amount of incoming energy is balanced by the same amount of outgoing energy.
What is convection?
Convection is the transfer of heat from the Earth’s surface into the atmosphere.
How does convection work in Earth’s atmosphere?
When a layer of air receives enough heat, it expands and is pushed upward by buoyancy. Then air becomes denser and moves laterally until it begins to sink and then begins to rise again as it warms. Atmospheric convection currents may cause breezes, winds, cyclones and thunderstorms.
What is radiation budget?
Radiation budget refers to the balance between incoming radiation from the Sun and the outgoing thermal, or longwave and reflected shortwave energy from Earth.
How is the radiation budget balanced globally?
Globally the budget is balanced as the amount of incoming solar radiation is transformed into latent heat, or even kinetic energy. Energy transfers in the oceans along with the atmosphere keep the radiation budget in balance.
How is the radiation balanced locally?
But locally the Radiation Budget is unbalanced because tropical regions retain more insolation, while less is retained in higher latitudes.This accounts for differences in the temperature and pressure of air masses that originate in both regions affecting weather throughout the planet
What is an air mass?
Large bodies of air that pass slowly over large areas of Earth’s surface and they take on the characteristics of that region such as temperature and humidity.
What is a source region?
the area from which the air mass derives its characteristics
