Tropics
Defined by 23.5 North or South of equator, and a dailey temperature range greater than the annual
High Pressure
Less clouds and more solar radiation
Low Pressure
More clouds, area of convergence
Equation of State
Pressure (P) = density (roe)
gas constant (R)
temperature (T)
Climate
Defined by temperature, moisture, pressure, wind speed (and direction), and air density
1st law of thermodynamics
A change in energy input must be matched by increase in energy content or work done within a system
Continuity Equation
Applying to air, the mass of it does not change; compression in one place leads to expansion at another
Isobaric Surface
The surface along which atmospheric air pressure is not changing. Cooler temp will lead to higher pressure
Coriolis Force
An imaginary force that occurs because of the earth's rotation. In north deflects to right and in south to left
Hydrostatic Equilibrium
A balance between pressure gradient and gravity
Vorticity
The tendency of spin in the atmosphere
Wind Speed
Wind is faster higher due to less friction and can lead to over-turning called wind shear
Insolation
Solar radiation received at the surface
Irradiance
The energy from radiation received at the surface
Solar Constant
1367 watts per square meter
Short Wave Radiation
Visible and what we receive (wavelength = 2.2 micro meters)
Long Wave Radiation
What radiation bounces back and what we cannot see
Angle of Incidence
Angle at which the sun hits the earth
Zenith
When the sun is perpendicular to the surface, or right above you (90�)
Water temperature
The hotter it is, the more fuel a storm has
Latent Heat
Heat energy related to the changing of phase
Seasons
Occur due to change in angle of incidence due to the 23.5% tilt of the earth
Deserts
Generally located just north or south of equator and are the areas of highest highest insolation
Albedo
Reflectivity, the higher it the more reflective it is
Hurricanes are from...
Pacific East and Atlantic
Typhoons are from...
Pacific West
Cyclones are from...
Indian Ocean
Specific Heat Capacity
Higher with density especially water (4200JkgK) and low in air (100JkgK)
Hadly Air Cell
Just north or south of equator and pushes air east from 30�
Inter Tropical Convergence Zone (ITCZ)
The point of convergence for wind around equator. It will shift depending on season (north in summer)
Diurnal Temperature Range
The difference between max and min temperatures on a particular day (most dramatic at deserts)
Oceans
Will stabilize climates near them and have currents than can bring unexpected cold or warm water to regions
ENSO
El Ni�o (or La Ni�a) southern oscillation, which is the reducing or increasing of easterly trade winds
El Nino
When the trade winds slow. This causes a decrease of upwelling on the west coast of the Americas and therefore warmer water which can be cause for storms
La Ni�a
An exaggeration of normal conditions, with the easterly wind flow increased. Causes excess of upwelling and storms to be trapped near Asia (increased rainfall in monsoonal season)
ENSO Reoccurrence
Variable, can be between 3-7 years
Walker Circulation
In the tropical pacific and is associated with trade wind strength
SOI
Used for measuring El Ni�o by calculating difference in sea surface pressure, high pressure over the western pacific is a sign of an El Ni�o event
Slosh
The term loosely used for describing the increase in sea surface height regarding the decrease in trade winds
El Ni�o thermocline
Is flat from east to west as opposed to the normal conditions where it is lower in the west and higher in the east
Thermocline
A layer of water within a large body that sharply separates regions of different water temp
Upwelling
When colder nutrient water is brought to the surface
El Ni�o Global Consequences
(1) Australian drought and fire (2) Indonesian agriculture struggles, leading to starvation (3) water shortages and drought in India (4) increased typhoon activity in Tahiti (5) South American fishing industries devastated (6) pacific island reef destruct
El Ni�o rain
El Ni�o will cause increased rain in the south west through Florida but less in the north (Rockies)
Climate Change and El Ni�o
More experiments need to be done to determine correlation, they seem to be a little stronger, however
Monsoons
The Season of Winds" which is in reference to the seasonal shifting of winds in the Indian Ocean and surrounding regions. It is a seasonal change
Summer Monsoon
Wind comes from the southwest and flows over the warmer land (low pressure now) and brings with it rain
Winter Monsoon
Wind comes from the northeast and flows over the warmer ocean (low pressure now) and brings a dry season
Monsoons' Physical Mechanisms
(1) the differential heating of water (which takes longer) and land (2) Coriolis Force (3) the role of water which stores and release energy (latent heat) as phase changes occur
Monsoonal Rain
Occurs during the summer monsoon and happens because as air rises (due to low pressure) it cools, condenses, and becomes rain (which causes latent heat to be released which increases the cycle; more dramatic over water bodies)
Trough (wind)
A stretched and long area of low pressure, key agent in precipitation
Components of Indian Monsoons
(1) Monsoon Trough (2) Mescarene high (air/jet stream that leads to monsoon and is effected by Coriolis (3) low level jet (4) Tibetan High, elevated land means thin atmosphere and strong solar radiation (5) Easterly Tropical Jet (6) monsoon cloudiness (7)
Components of East Asia Monsoon
(1) Australian High (2) Cross Equatorial Jet (3) SW Monsoon (4) Monsoon Trough (5) Easterly Tropical Jet (6) Western Pacific High (7) Mei-Yu front/mid-latitude disturbances
Cyclone
An area of low pressure
Anti-Cyclone
An area of high pressure
Percent of Population Dependent on Monsoonal Rainfall
60%
Summer Monsoon Onset
June 1st
ENSO and Monsoons
El Ni�o will generally reduce the summer rainfall associated with monsoons in India
African Monsoon
Occurs in two regions, east and west Africa. West influences North Africa and the Atlantic, while the East African monsoon influences the rest of the continent (more than west).
African Monsoon in Winter
For the west, climate is warm and dry as winds blow from the Sahara. For the east, wind blows southwest with no real change in moisture
African Monsoon in Summer
For the west, climate is cool and wet as wind blows in from the Atlantic. For the east, wind blows northwest with no real change in moisture
North American Monsoon
This is the most predictable weather pattern that we have. During summer it delivers 35-45% of Arizona's annual rain and 60% of Northern Mexico's. Wind pattern is defined as blowing wind coming from the W/NW in winter (from CA/Nevada) and with wind coming
El Ni�o and American Temperature
During El Ni�o it is expected that the south will be cooler and the north will be warmer (northwest especially will be warmer)
To get out of drought we need...
11 trillion gallons of water (200-300% more than normal)
Lower Pressure
This can act as an area of convergence for storms and as such the lower the pressure the greater the storm
Thunderstorm
Also known as an electric or lightening storm is a strong weather event that occurs in association with cumulonimbus clouds (puffy and tall). The process is as such: (1) starts as a fair weather cumulus, which are flat on the bottom due to waters due poin
Meso-scale Convective Complexes
A large group of thunderstorms
Cumulus Stages
(1) fair weather (2) congested (3) cumulonimbus
Cumulonimbus
A towering puffy cloud associated with thunderstorms which pull warm air and pushes down cold air creating fronts (before a storm starts you can feel cold winds known as the "gust front")
Storm Downdraft
Sometimes downdrafts can force updrafts and therefore more clouds, these fronts can create tornados
Tornados
Extremely small circulating winds that happen due to very different pressures over a very small scale and due to Coriolis. They are must common during spring and summer months in the evening