Unit 2 Asma The Atmosphere

Front 1

Describe the composition of the earth’s atmosphere

Back 1

extend from the earth’s surface to space and are composed primarily of nitrogen, oxygen, argon and trace gases.

Front 2

What is the specific composition of nitrogen in the dry atmosphere

Back 2

78.08

Front 3

What is the specific composition of oxygen in the dry atmosphere

Back 3

20.95

Front 4

What is the specific composition of argon in the dry atmosphere

Back 4

0.93

Front 5

What is the specific composition of carbon dioxide in the dry atmosphere

Back 5

0.03

Front 6

What is the specific composition of neon in the dry atmosphere

Back 6

0.0018

Front 7

What is the specific composition of helium in the dry atmosphere

Back 7

0.0005

Front 8

What is the specific composition of krypton in the dry atmosphere

Back 8

0.001

Front 9

What is the specific composition of xenon in the dry atmosphere

Back 9

0.000009

Front 10

What is the specific composition of hydrogen in the dry atmosphere

Back 10

0.00005

Front 11

What is the specific composition of methane in the dry atmosphere

Back 11

0.0002

Front 12

Does humidity change the proporitons of gases in the atmosphere?

Back 12

Atmospheric water vapor (humidity) changes the proportions of the gases in the atmosphere. A global average of 1% is used for standards but it can be as high as 4% in the tropics. The amount of water vapor that can be retained in the air is directly related to temperature; higher the temperature the greater the amount of water possible.

Front 13

What is the effect of heat on the atmosphere?

Back 13

Heat is a form of physical energy, when transferred to the atmosphere it increases its temperature. This takes place by radiation, conduction and convection. As air is heated it expands becoming less dense and therefore rises. As the air cools is becomes denser and begins to sink. This resulting vertical movement of air results in wind and weather.

Front 14

Describe atmospheric pressure and how it is caused

Back 14

Just as a column of water exerts a force or weight per unit area, the column of air above a specific point exerts a pressure (force), which is usually expressed in inches of mercury (in Hg).

Front 15

With increasing altitude what happens to the density of the air?

Back 15

It is inversely proportional, it decreases therefore the pressure exerted by the remaining air above you will be less.

Front 16

An increase in altitude will result in a ______ of atomospheric (barometric) pressure.

Back 16

Reduction

Front 17

Convert 18K ft to meters

Back 17

multiply by 0.3048, like this:
18000 feet (ft) × 0.3048 = 5486.4 meters (m).

Front 18

Convert 5500 meters to feet

Back 18

multiply by 3.28, like this:
5500 meters (m) × 3.28 = 18040 feet (ft).

Front 19

Define the U.S. Standard Day (pressure and temperature)

Back 19

Observing the daily weather report it becomes apparent that atmospheric pressure varies continuously over a relatively narrow range. The average of these fluctuations, adapted to specific standard conditions of temperature and latitude, is defined as the standard atmosphere.

Front 20

At latitude of 45o, what is the standard atmosphere at sea level

Back 20

Altitude Sea Level
Temp 15oC
Pressure 1013.2 mb
29.92 in Hg
760 mm Hg (torr) 14.7 psi

Front 21

What are the standard units used to measure atmospheric pressure and convert a given pressure from one unit to another?

Back 21

Milibar, inches of mercury, millimeters of mercury, pounds per square inch

Front 22

Describe milibar

Back 22

A common metric unit of atmospheric pressure, equal to 0.001 bar, about 0.0295 inches (0.7501 millimeters) of mercury, or about 0.014 504 lb/in2. A millibar is the same thing as a hectopascal (hPa), and some weather agencies have replaced the millibar with the hectopascal in an effort to conform to the SI (International System of Units). However, many meteorologists resist this change and continue to use millibar.

Front 23

Describe inches of mercury

Back 23

A traditional unit of atmospheric pressure. In the United States, atmospheric pressure is customarily expressed as the height of a column of mercury exerting the same pressure as the atmosphere. When a traditional mercury barometer is used, this height is read directly as the height of the mercury column. These readings must be corrected for temperature since mercury, like most liquids, tends to expand as it warms

Front 24

Describe millimeters of mercury

Back 24

A unit of pressure equal to the pressure exerted at the Earth's surface by a column of mercury 1 millimeter high. When a traditional mercury barometer is used, the pressure is read directly as the height of the mercury column in millimeters

Front 25

Describe pounds per square inch

Back 25

A traditional unit of pressure. Psia means pound per square inch absolute, which is the total pressure including the pressure of the atmosphere.

Front 26

How do you convert inches of mercury to milibars?

Back 26

multiply by 33.86

Front 27

How do you convert milimeters of mercury to milibars?

Back 27

multiple by 13.33

Front 28

How do you compute a temperature using the standard temperature laspe rate?

Back 28

As one ascends in altitude, there is a steady decrease in atmospheric temperature known as the lapse rate. Although the rate may vary due to location or local atmospheric conditions, the standard temperature lapse rate is 6.5oC per km or 3.5oF per 1000 ft.

Front 29

How do you convert Celsius temperatures to Fahrenheit with mental math?

Back 29

Double the Celsius temperature (multiply by 2).

Take 1/10 of this number (2 * 1/10 = 0.2) and subtract it from the number above.

Add 32o to adjust for the offset in the Fahrenheit scale.

Front 30

Convert 37degreees Celsius to Fahrenheit

Back 30

37 * 2 = 74
74 * 1/10 = 7.4 74 - 7.4 = 66.6 66.6 + 32 = 98.6o F

Front 31

Convert 50 degrees Farenheit to Celsius

Back 31

50 - 32 = 18 18 / 2 = 9
9 * 1/10 = .9 9 + .9 = 9.9

Front 32

What are the physiological divisions/zones of the atmosphere?

Back 32

Physiologic zone, physiologically deficient zone, space eqivilent zone, space

Front 33

Describe the physiological zone

Back 33

Sea level to 10,000 ft. (3000m)

* Humans are well adapted

* Possibility of middle ear or sinus problems during ascent of descent.

Front 34

Describe the physiologically deficient zone

Back 34

10,000 to 50,000 ft. (3000m to 15,200m)

* Decreased barometric pressure reduces the partial pressure of inspired oxygen and causes altitude hypoxia (hypoxic hypoxia)

* Protective oxygen is mandatory in this zone

* Additional problems may arise from trapped and evolved gases

Front 35

Describe the space equivilent zone

Back 35

"50,000 ft to 120 miles (15,200m to 200 km)

* Total pressure decreases from 87 to less than 1 mm Hg

* Supplemental 100% oxygen no longer provides protection from hypoxia

* Protection from this environment is required in the form of a sealed cabin or full-pressure suit.

* Additional physiological problems are possible radiation effects and boiling of body fluids (ebullism). Ebullism will occur when total barometric pressure is less than vapor pressure of water at 37oC which is reached at 63,000 ft (Armstrong’s Line).

Front 36

Describe the space zone

Back 36

Altitudes beyond 120 miles (200 km)

* Protection is provided by a sealed cabin or full pressure suit.

* Physiological effects are the same as the Space equivalent zone.

Front 37

List the temperature divisions/zones of the atmosphere

Back 37

Troposphere, stratosphere, mesosphere, thermosphere

Front 38

Define troposphere

Back 38

* Region nearest the surface, uniform degree of temperature with altitude (standard temperature lapse rate). Temperature inversions are common.

* The domain of weather this region is in convective equilibrium with the sun-warmed surface of the earth

* The tropopause (between 8 and 16 km / 26,000 – 52,500 ft) (higher and colder over the equator) is the domain of high winds and highest cirrus clouds.

Front 39

Define stratosphere

Back 39

* Nominally constant temperature

* Thicker over the poles and thinner, or even non-existent over the equator

* Max atmospheric ozone found at the stratopause

* Rare nacreous clouds found near stratopause

* Stratopause reaches 45 km (147,500 ft)

* Temperatures are in the order of arctic winter temperatures

Front 40

Define mesosphere

Back 40

* Region of first temperature maximum

* This region is above the stratosphere and below the major temp minimum at 80 km, which is the mesopause

* Relatively warm region between two cold ones, region where most meteors disappear

* Mesopause is found at altitudes from 70 to 85 km (229,600 – 278,800 ft)

* Mesopause is in radiative equilibrium between ultraviolet ozone heating by the upper fringe of the ozone region and the infrared ozone and carbon dioxide cooling by radiation to space.

Front 41

Define thermosphere

Back 41

* Region of rising temperature above the major temp minimum around 80 km

* Domain of auroras with no upper altitude limit

* Temperature rises at the base of the thermosphere are attributed to too infrequent collisions among molecules to maintain thermodynamic equilibrium

* The potentially enormous infrared radiative cooling by carbon dioxide is not actually realized owing to inadequate collisions

Front 42

Define Boyle's law

Back 42

The volume of a gas in inversely proportional to its pressure, temp remaining constant.

* At 18,000 ft, pressure is half what it is at sea level; a given volume will be twice its initial volume at that altitude.

Boyle’s Law is expressed as follows V1/V2 = P2/P1
V1 = Initial Volume V2 = Final Volume P1 = Initial Pressure P2 = Final Volume

Front 43

Define Charles' law

Back 43

The pressure of a gas is directly proportional to its absolute temperature, volume remaining constant.

* The contraction of gas due to temperature decreases at altitude, however, in no manner compensates for the expansion due to the corresponding decrease in pressure. Charles law is expressed as follows:

V1/V2=T1/T2
V1 = Initial volume V2 = Final volume T1 = Initial Temp T2 = Final Temp

Front 44

Define Henry's law

Back 44

Henry’s law deals with the solubility of gases in liquids.The amount of gas in a solution varies directly with the partial pressure of gas over the solution. The absolute amount of any gas dissolved in a liquid under conditions of equilibrium (# of molecules entering and leaving the liquid per unit time is equal) is dependent on the solubility of the gas in the liquid and the temperature, as well as the partial pressure of the gas.

Front 45

Define Dalton's law of partial pressure

Back 45

The total pressure of a mixture of gases is the sum of the individual or partial pressures of all the gases in the mixture. One can calculate the partial pressure of a gas in a mixture simply by knowing the percentage of concentration in that mixture. P = P1 + P2 + P3 and so forth P = total pressure P1, P2 and so forth are the partial pressures Partial pressure of each gas in a mixture is derived by the following equation
P1 = F1 x P
P1 = partial pressure F1 = fractional concentration P = total pressure P (O2 at sea level) = 21% x 760 mm Hg 159.6 mm Hg = .21 x 760 mm Hg