CLIMATE

I ATMOSPHERE
The earth's outer layer is fluid

The atmosphere is stratified by density, with the densest layer (the heaviest) being nearest the ground. This layer is the TROPOSPHERE.

There is great vertical movements in the troposphere, where our weather occurs.

Above the troposphere, separated by the

TROPOPAUSE...... there is the STRATOSPHERE.

interaction between the troposphere and the stratosphere.

--- Thus material injected into the stratosphere is not easily removed into the troposphere.

The main components of the atmosphere are Nitrogen

(N2) and Oxygen (02).

Other components include Argon (Ar), Carbon dioxide (CO2), Methane (CH4), Ozone (03), and Water Vapor.

- in the troposphere, it is a pollutant

- in the stratosphere, it shields the earth's

surface from damaging solar UV radiation.

- plays a critical role in heat transport

- evaporation removes energy from water; water vapor carries this energy (Latent Heat) away.

- Condensation of the water vapor releases energy. example: HURRICANES' power derives from condensing water vapor within rising air in the eye.
 
 


HEAT BUDGET

Solar Heating

--the incoming -radiation (UV and visible)

is balanced by re-radiation of heat from the earth (infrared) to space.

-- Green house gases cause this process to occur at higher temperatures.

WINDS

--water vs. land

--high latitude vs. low latitude

UNEQUAL HEATING CAUSES CONVECTION CELLS

WARM, MOIST (LESS DENSE) AIR RISES, THEN COOLS AND SINKS---

THE RETURN, SURFACE FLOW ARE THE SURFACE WINDS

This is complicated by the Earth's rotation, which gives

rise to a force called the

CORIOLIS EFFECT

This causes moving objects to be deflected:


 

TO AN OBSERVER STANDING ON THE ROTATING DISK, AN OBJECT IS APPARENTLY DEFLECTED TO THE RIGHT AS THE DISK ROTATES UNDER THE OBJECT

THE INTENDED TARGET "X" IS ROTATED WITH THE DISK. THEREFORE IT SEEMS THAI' PROJECTED OBJECT 'D "MISSES" TO THE RIGHT!!!!

The next two viewgraphs illustrate how low and high pressure areas lead to winds

1) There are global high and low pressure areas which dictate the general flow of the winds and climate.

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2) There are also regional, or local, low and high pressure systems coresponding to divergence and convergence of air.

Hurricanes are intense low pressure systems, where air rushes in and rises, releasing enormous amounts of energy:

II. Oceans

Temperature

the difference between evaporation and

precipitation (E-P).

- S is large in the central subtropical gyres, where there is less rainfall and strong prevailing winds.

- small in central gyres as well. - significant at high latitudes

Highest salinities occur where there is an excess of evaporation over precipitation. Lowest salinities occur where there is an excess of precipitation, and where there are inputs of river and melt water.

The distribution of water and heat are related through the heat stored in water and in water vapor.

To understand these distributions, it is useful to construct budgets. In budgets,

SUM of INPUTS = SUM of OUTPUTS

1) WATER BUDGET

Precipitation + runoff + current transport + meltwater

= evaporation + current transport

2) HEAT BUDGET

Heat from sun + heat carried in from currents =

latent heat lost from evaporation

+ longwave radiation

+ heat lost to the atmosphere

+ heat carried away by currents

BOX MODELS


 

The system is at steady state, in that the volume of the basin does not change..... there is a balance of inputs and outputs.

STRUCTURE OF THE OCEAN

- temperature and salinity variable with season and location - 0.5 - 1 km thick

- thermocline

- halocline

- acts as a barrier between the surface and deeper water.

- greater than 3 km

- it's T,S not very variable. It's

characteristics fixed in polar regions

Temperature - Salinity Diagrams

T,S changes only at the surface

Therefore, T and S can be used to trace the mixing of different water masses.

CURRENTS

I. Surface Currents

A) Open Ocean

- surface currents resemble general wind pattern. - closed current system.

- bounded by westward flowing

equatorial currents and eastward flowing high latitude currents.

The affect of wind upon the water is complicated by the earth's rotation, which is called the Coriolis Force.

it..... and so on. The current speed decreases with depth in this process. Ekman Transport.......

The relationship between the wind, earth's rotation and the surface ocean leads to a net transport which is 90' to the right of the wind.

Leads to convergence in gyres


GEOSTROPHIC FLOW