### fluid | air:

Fresh air
* More fresh air means more oxygen to the brain.
* Most fresh air contains oxygen.
* contains almost no carbon dioxide when it is first inhaled
* helps prevent disease.
* is an important, and regulated, part of a building's indoor climate
  - as important as watering
  - drawn from outdoors for combustion
  - essential to general wellbeing and resistance to disease
  - just as important to boilers, furnaces and gas-fired water heaters as it is to people
* is located in countrysides
  - fields
  - parks
* is the main treatment for very mild cases of carbon monoxide in healthy people
  - quickest antidote to carbon monoxide poisoning
  - very important to hedgehogs

Gulf air
* meets air
  - canadian air
* meets cold air

Heated air
* expands so the hot air had slightly greater pressure than the air outside the bottle.
* has a greater capacity to hold moisture than cooler air.
* is able to hold more moisture
  - used primarily to speed up the evaporation of the moisture in the wood
* rises to ceiling level and is quickly cooled by the cold surfaces it touches.

### fluid | air:

Hot air
* Most hot air has refraction
  - holds moisture
* Some hot air holds vapor
  - water vapor
* can make pollution worse
  - mean blockage in the vent or chimney
* drying also makes the herbs, spices, and vegetables extremely difficult to rehydrate.
* expands and rises and molecules flow away from it to colder areas and collect there
  - spreads out and it becomes lighter than cool air
* expands, and therefore is thinner than cold air.
* has a tendency to rise, because it is less dense than cold air.
* has lower density and rises creating lower surface pressure
  - therefore sound travels slower
  - more water vapor than cold air
* is air
* is less dense than cool air and less density produces less lift for the same speed
  - and thus rises
  - dense, and decreases power
  - lighter and rises to the top by convection
* is lighter than cold air, and tends to rise upwards, lowering the pressure underneath
  - the surrounding colder air and causes the balloon to rise
  - thinner and lighter than cool air
  - what is needed to make the air go faster
* produced by a shower has a tendency to rise.
* radiates upward from land surfaces heated by the sun.
* refers to virtual, or paper emissions trading.
* regenerates the desiccant by evaporating the moisture and exhausting it to the outside.
* rises above cool air, and moist air is lighter than dry air
  - at equator, moves away, cools and sinks
* rises because it IS heat, and heat has levity
  - expands when heated and therefore becomes less dense
* rises because it is less dense than surrounding cooler air at the same pressure
  - only about half as dense as cold air
  - from the equator, creates a low pressure area, and flows towards the north pole
* rises in a process called convection
  - warm areas, travels to cold areas, and falls
  - when heated by the sun, carrying water vapor into the sky
* rises, and once the balloon is filled with hot air, it rises as well
  - creating a low pressure system
  - taking large amounts of pollutants skyward
* rising over the equator pushes northward and southward.

Hotter air
* holds more water vapor, creates feedback loop so the earth gets warmer.
* rises, so the air above the shore rises up, creating a low pressure area.

Humid air
* Most humid air contains airborne particles
* can produce lower base clouds and temperate areas can produce higher base clouds
  - promote houseburn, sweat, and mold
  - more moisture than dry air
* hits the cold glass, and water droplets form on dust particles.
* is actually lighter than dry air.
* rises because it is lighter than dry air, and is the cause of the updrafts.
* weighs less than dry air at the same temperature and pressure.