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Climate and weather Cheat Sheet (DRAFT) by

Climate and weather basics

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Weather

The state of the air and atmosphere at a particular time and place i.e. the temper­ature and other outside conditions (such as rain, cloudi­ness, etc.)

Climate

the weather conditions prevailing in an area in general or over a long period

Seasons

Seasons happen because Earth's axis is tilted at an angle of about 23.4 degrees and different parts of Earth receive more solar energy than others.

The direction of Earth's tilt doesn't change ...

The Southern Hemisphere points away from the Sun, creating winter during the months of June, July and August. Summer in the Southern Hemisphere is in December, January, and February, when the South Pole is tilted toward the Sun and the Northern Hemisphere is tilted away.
  

Earth's Energy Balance

The Earth’s atmosphere is heated up unequally
1. Sphericity - The nearly spherical shape of the Earth produces uneven insola­tion.
2. Tilt - The Earth’s axis is tilted 231/2° from the perpen­dicular
3. Rotation - Earth turns on its axis once every 24 hours (day/n­ight)
4. Revolution - Earth orbits around the sun once every 3651/4 days (a year)

Surface areas receiving solar insolation

Incoming radiation from the Sun is mainly higher energy, short-wave radiation that heats the Earth’s surface.

The incoming solar energy that reaches the Earth’s surface is called insolation and is unevenly distri­buted over the Earth.

Earth's Heat Engine - Finding balance

There is a positive heat balance within the tropics, and a negative heat balance in the polar regions.
But the Earth does not steadily get hotter at the tropics or colder at the poles. There is a balance between incoming solar radiation and outgoing radiation from the Earth.

This happens through two major transfers of heat: 80% by wind and 20% by water.
  

80% - Air circul­ation

20% - Ocean currents

Coriolis Force

Coriolis Force deflects wind
The Coriolis force applies to movement on rotating objects. It is determined by the mass of the object and the object's rate of rotation. The Coriolis force is perpen­dicular to the object's axis. The Earth spins on its axis from west to east.

The Coriolis force, therefore, acts in a north-­south direction. The Coriolis force is strongest near
the poles, and zero at the Equator.

In the Southern Hemisp­here, currents are deflected to the left.

Wind

Wind is the movement of air caused by the uneven heating of the Earth by the sun. Differ­ences in atmosp­heric pressure generate winds.
At the Equator, the sun warms the water and land more than it does the rest of the globe. Warm equatorial air rises higher into the atmosphere and migrates toward the poles. This is a low-pr­essure system.
At the same time, cooler, denser air moves over Earth’s surface toward the Equator to replace the heated air. This is a high-p­ressure system. Winds generally blow from high-p­ressure areas to low-pr­essure areas.
The boundary between these two areas is called a front. The complex relati­onships between fronts cause different types of wind and weather patterns.

Air movement

Factors Affecting Climate & Weather

Latitude
Affects relative position of sun in the sky. (Think equator vs the poles)
Altitude
Temper­­atures decrease as as height above sea level increases (1 degree per 100m).
Prevailing winds
Winds carry different amounts of moisture and heat depending on where they originate
Ocean currents
The sea moderates temper­atures.

Clouds

Stratus: Layered clouds that are low, usually look like a blanket.
Cumulus: White and fluffy; fast moving, may bring rain showers – especially when the base is grey.
Cumulo­­nimbus: These are much deeper clouds that climb high into the atmosp­­here. They often contain a lot of heavy rain and are associated with thunder and lightning storms.
Cirrus: High, wispy clouds, Made up from ice crystals.