1. ATMO 336 Climate, Weather and Society Lecture Atmospheric Composition Temperature, Density, Pressure Vertical Structure Weather vs. Climate

2. Atmospheric Composition Permanent Gases N 2 and O 2 are most abundant gases Percentages hold constant up to 80 km Ar, Ne, He, and Xe are chemically inert N 2 and O 2 are chemically active, removed & returned Ahrens, Table 1.1, 3 rd Ed.

3. N 2 Boiling point: 77 K or -196°C or –320 °F O 2 Boiling point: 90 K or -183 °C or -297 °F N 2 and O 2 Balance between input (production) and output (destruction): Input: plant/animal decaying Sink: soil bacteria; oceanic plankton-->nutrients Input: plant photosynthesis Sink: organic matter decay chemical combination (oxidation) breathing

4. Atmospheric Composition Important Trace Gases Ahrens, Table 1.1, 3 rd ed. Which of these is now wrong even in the 4th edition of Ahrens?

5. Sources vegetative decay volcanic eruptions animal exhalation combustion of fossil fuels (CH 4 + 2 O 2 > 2 H 2 O + CO 2 ) Sinks photosynthesis (oxygen production) dissolves in water phytoplankton absorption (limestone formation) Carbon Dioxide CO 2

6. CO 2 Trend “Keeling Curve” Some gases vary by season and over many years. The CO2 trend is the cause for concern about global warming. CO 2 increases in northern spring, decreases in northern fall http://earthguide.ucsd.edu/globalchange/keeling_curve/01.html

7. H 2 O Vapor Variability Precipitable Water (mm) Some gases can vary spatially and daily

8. Aerosols 1 cm 3 of air can contain as many as 200,000 non-gaseous particles. –dust –dirt (soil) –salt from ocean spray –volcanic ash –water –pollen –pollutants

9. Aerosols - Volcanic Ash Fig. 1-4, p.6

10. Aerosols - Dust Particles Dust Storm on Interstate 10, between Phoenix and Tucson, AZ.

11. Aerosols Provide surfaces upon which water vapor can condense. Provide a surface area or catalyst needed for much atmospheric chemistry. Aerosols can deplete stratospheric ozone. They can also cool the planet by reflecting sunlight back to space.

12. Scientific Notation How do we write very big or very small number? Scientific Notation is the way that scientists compactly write very large or small numbers It can be thought of as a coefficient times ten raised to an exponent

13. Scientific Notation Speed of light is 300,000 meters per second (m s -1 ) Scientific Notation for speed of light is 3.0 x 10 5 m s -1 Wavelength of visible light is close to 0.0000005 meters Scientific Notation for wavelength would be 5.0 x 10 -7 m s -1

14. Scientific Notation Example… Distance between the Earth and the Sun is 150,000,000 kilometers Scientific Notation for distance would be?

15. Scientific Notation Example… Distance between the Earth and the Sun is 150,000,000 kilometers Scientific Notation for distance would be? 1.5 x 10 8 km

16. Fundamental Concepts Let us introduce three fundamental concepts... Temperature Density Pressure

17. Temperature Scales Fahrenheit ( o F) - relative US public standard Celsius ( o C) - relative Freezing point 0 o C Boiling point 100 o C o C= 5/9 ( o F-32) Kelvin (K) - absolute K= o C+273 Ahrens p27

18. What is Temperature? Microscopic View Energy due to random jiggling of molecules Related to average molecular speed (v); 500 m/s for air at room temperature Maxwell Distribution K.E.=(1/2)mv 2 =(3/2)kT m = mass of one molecule k = Boltzmann constant =1.38065×10 −23 joule/K (joule is unit of energy)

19. Impact of Extreme Temperatures on Humans Hypothermia Condition in which the internal temperature drops below that required for normal metabolism and bodily functions. Hyperthermia Condition in which the internal temperature rises above threshold that leads to organ failure.

20. Hypothermia Stages Stage 1 http://en.wikipedia.org/wiki/Hypothermia http://en.wikipedia.org/wiki/Hypothermia –Body temperature drops by 1-2  C (Normal body temperature is 37  C) –Mild to strong shivering occurs –Hands become numb, can’t do complex tasks –Blood vessels in outer extremities constrict –Breathing becomes quick and shallow –Goose bumps appear

21. Hypothermia Stages Stage 2 http://en.wikipedia.org/wiki/Hypothermia http://en.wikipedia.org/wiki/Hypothermia –Body temperature drops to 2-4  C below normal –Shivering becomes more violent –Lack of coordination apparent, e.g. stumbling –Mild confusion –Surface blood vessels contract further –Skin pallor becomes pale –Lips, ears, fingers and toes can turn blue

22. Hypothermia Stages Stage 3 http://en.wikipedia.org/wiki/Hypothermia http://en.wikipedia.org/wiki/Hypothermia –Body temp. drops below 32  C (90  F) –Shivering usually stops –Difficulty speaking, slow thinking, amnesia –Inability to use hands and stumbling –Cellular metabolic processes shut down

23. Hypothermia Stages Stage 3 (cont’d) –Body temp. drops below 30  C (86  F) –Walking nearly impossible –Incoherent or irrational behavior, even stupor –Pulse and respiration rates slow significantly –Heart arrhythmia; tachycardia, atrial fibrillation –Major organ failure. Clinical death occurs. –Decreased metabolism delays brain death

24. http://www.weather.gov/os/windchill/index.shtml

25. Hypothermia Prevention www.mayoclinic.com COLD - Cover, Overexertion, Layers, Dry Cover. Wear a hat to prevent body heat from escaping from your head, face and neck. Cover your hands with mittens instead of gloves. Overexertion. Avoid activities that would cause you to sweat a lot. Layers. Wear loose-fitting, layered, lightweight clothing. Outer clothing made of tightly woven, water-repellent material is best for wind protection. Wool, silk or polypropylene inner layers hold more body heat than cotton does. Dry. Stay as dry as possible.

26. Hyperthermia Stages http://en.wikipedia.org/wiki/Hyperthermia http://en.wikipedia.org/wiki/Hyperthermia –Temperatures above 40°C (104°F) are life- threatening –41°C (106 °F) brain death begins –45°C (113°F) death is nearly certain –Core temperatures above 50°C (122°F) cause muscle rigidity and certain, immediate death

27. Hyperthermia Stages http://en.wikipedia.org/wiki/Hyperthermia http://en.wikipedia.org/wiki/Hyperthermia –In its advanced stage, hyperthermia is called heat stroke or sun stroke –Heat stroke is a medical emergency that requires hospitalization –Heat stroke can come on suddenly, but it usually follows the less-threatening condition of heat exhaustion or heat prostration, which in turn is often follows heat cramps

28. Heat Cramps www.mayoclinic.com/health/first-aid-heat-cramps –Mild form of heat exhaustion –Cramps in the calves, arms, abdomen and back, occurrence is common in athletes –Inadequate intake of fluids or electrolytes is very often a contributing factor –Treatment: rest and cool down; drink clear juice or electrolyte drink; stretch muscle group

29. Heat Exhaustion Symptoms www.mayoclinic.com/health/first-aid-heat-exhaustion www.mayoclinic.com/health/first-aid-heat-exhaustion Feeling faint or dizzy Nausea Heavy sweating Rapid, weak heartbeat Low blood pressure Cool, moist, pale skin Low-grade fever Heat cramps Headache Fatigue Dark-colored urine

30. Heat Exhaustion Treatment www.mayoclinic.com –Get the person out of the sun and into a shady or air-conditioned location. –Lay the person down, elevate the legs and feet slightly. –Loosen or remove the person's clothing. –Have the person drink cool water.

31. Heat Exhaustion Treatment www.mayoclinic.com –Cool the person by spraying or sponging them with cool water and fanning. –Monitor the person carefully. Heat exhaustion can quickly become heatstroke. –If fever greater than 102 F (38.9 C), fainting, confusion or seizures occur, dial 911 or call for emergency medical assistance.

32. Heat Stroke Symptoms www.mayoclinic.com High body temperature of 104  F (40  C) or higher is the main sign of heat stroke. Cessation of sweating. In heatstroke brought on by hot weather, your skin is hot and dry to the touch. In heatstroke brought on by strenuous exercise, your skin usually feels moist. Hyperventilation, rapid and shallow breathing.

33. Heat Stroke Symptoms www.mayoclinic.com Rapid heart rate and pulse (tachycardia). Your blood pressure usually remains normal, but your pulse may increase to around 130 beats a minute, well above the normal level for adults (60 to 100). Neurological symptoms. You may have seizures, lose consciousness, slip into a coma, hallucinate, or have difficulty speaking or understanding what others are saying. Muscle cramps or weakness. Your muscles may feel tender or cramped in the early stages of heatstroke, but may later go rigid or limp.

34. Heat Stroke Treatment www.mayoclinic.com MEDICAL EMERGENCY! Doctor/hospital may administer… Cold water immersion. (Currently out of favor.) Evaporative cooling techniques. Ice packs and cooling blankets. Internal “flushing” techniques. Medications to stop treatment-caused shivering.

35. Heat Index http://www.weather.gov/os/heat/index.shtml

36. Heat Injury Prevention www.mayoclinic.com Wear loose-fitting, lightweight clothing. Seek a cooler environment. A good way to start cooling off is to get to a cooler environment, like an air-conditioned building or a shady spot. Drink plenty of fluids. Staying hydrated helps your body sweat and maintain a normal body temperature. Avoid diuretics (alcohol, caffeine). Take extra precautions with certain medications.

37. Apparent Temperature Current U.S. Apparent Temperature Map Current U.S. Apparent Temperature Map

38. What is Density? Density (d) = Mass (M) per unit Volume (V) d = M/V Typical Units: kg/m 3, gm/cm 3 Mass = # molecules  molecular weight (gm/mole) Avogadro number (6.023x10 23 molecules/mole)

39. Density Change Density (d) changes by altering either a) # molecules in a constant volume b) volume occupied by the same # molecules a b

40. Temperature-Density: Charles Law Consider volume of air If air is warmed: The molecules will move faster, have “stronger” collisions, and tend to become spaced farther apart Volume increases, so density decreases Warmer  less dense Charles Law Applet T(K) = constant x Volume at uniform pressure

41. What is Pressure? Pressure (p) = Force (F) per unit Area (A) Typical Units: pounds per square inch (psi), millibars (mb), inches Hg Average pressure at sea-level: 14.7 psi 1013 mb 29.92 in. Hg

42. Pressure Can be thought of as weight of air above you. (Note that pressure acts in all directions!) So as elevation increases, pressure decreases. Higher elevation Less air above Lower pressure Lower elevation More air above Higher pressure Bottom Top

43. Density and Pressure Variation Key Points 1.Both decrease rapidly with height 2.Air is compressible, i.e. its density varies Ahrens, Fig. 1.5

44. Why rapid change with height? Consider a spring with 10 kg bricks on top of it compressible The spring compresses a little more with each addition of a brick. The spring is compressible. 10 kg

45. Why rapid change with height? Now consider several 10 kg springs piled on top of each other. Topmost spring compresses the least! Bottom spring compresses the most! The total mass above you decreases rapidly w/height.  mass

46. Why rapid change with height? Finally, consider piled-up parcels of air, each with the same # molecules. The bottom parcel is squished the most. Its density is the highest. Density decreases most rapidly at bottom.

47. Why rapid change with height? Each parcel has the same mass (i.e. same number of molecules), so the height of a parcel represents the same change in pressure  p. Thus, pressure must decrease most rapidly near the bottom. pppp pppp pppp pppp

48. Water versus Air Pressure variation in water acts more like bricks, close to incompressible, instead of like springs. Air: Lower density, Gradual drop Higher density Rapid decrease Bottom Top Bottom Top Water: Constant drop

49. A Thinning Atmosphere Bottom Top Lower density, Gradual drop w/elevation Higher density, Rapid decrease w/elevation NASA photo gallery

50. Pressure Decreases Exponentially with Height Logarithmic Decrease For each 16 km increase in altitude, pressure drops by factor of 10. 48 km - 1 mb 32 km - 10 mb 16 km - 100 mb 0 km - 1000 mb 100 mb 10 mb 1 mb 16 km 32 km 48 km Ahrens, Fig. 1.5

51. Exponential Variation Logarithmic Decrease For each 5.5 km height increase, pressure drops by factor of 2. 16.5 km - 125 mb 11 km - 250 mb 5.5 km - 500 mb 0 km - 1000 mb

52. Equation for Pressure Variation We can Quantify Pressure Change with Height

53. What is Pressure at 2.8 km? (Summit of Mt. Lemmon) Use Equation for Pressure Change

54. What is Pressure at Tucson? Use Equation for Pressure Change Let’s get cocky… How about Denver? Z=1,600 m How about Mt. Everest? Z=8,700 m You try these examples at home for practice

55. Impact of Density and Pressure Changes on Humans Altitude sickness or hypoxia. Hypoxia means "deficient in oxygen." Hypoxemia means "deficient oxygen in blood.” Altitude sickness is caused by the decrease of oxygen with increasing elevation.

56. Altitude Sickness Symptoms Headache is a primary symptom used to diagnose altitude sickness, although headache is also a symptom of dehydration. A headache occurring at an altitude above 2,400 meters (8000 feet = 760 mb), combined with any one or more of the following symptoms, could be an indication of altitude sickness.

57. Altitude Sickness Symptoms en.wikipedia.org/wiki/Altitude_sickness en.wikipedia.org/wiki/Altitude_sickness No appetite, nausea or vomiting Fatigue or weakness Dizziness or light-headedness Insomnia Pins and needles Shortness of breath upon exertion Persistent rapid pulse Drowsiness General malaise Peripheral edema (swelling hands, feet, and face) Sign on Mt. Evans CO

58. Life-threatening Conditions en.wikipedia.org/wiki/Altitude_sickness en.wikipedia.org/wiki/Altitude_sickness Symptoms of extreme altitude sickness include: High altitude pulmonary edema (fluid in lungs) –dry cough; may progress to pink, frothy sputum –fever –shortness of breath even when resting High altitude cerebral edema (swelling of brain) –headache that does not respond to analgesics –unsteady walking –increasing vomiting –gradual loss of consciousness

59. Critical Altitude Conditions en.wikipedia.org/wiki/Altitude_sickness en.wikipedia.org/wiki/Altitude_sickness HAPE occurs in ~2% of those who are adjusting to altitudes of ~3000 m (10,000 feet = 700 mb) or higher. It can progress rapidly and is often fatal. Descent to lower altitudes alleviates the symptoms of HAPE.

60. Critical Altitude Conditions en.wikipedia.org/wiki/Altitude_sickness en.wikipedia.org/wiki/Altitude_sickness HACE occurs in 1% of people who are adjusting to altitudes of ~2700 m (9,000 feet = 730 mb) or higher. It can lead to coma or death. Descent to lower altitudes may save those afflicted with HACE.

61. Prevention of Altitude Sickness en.wikipedia.org/wiki/Altitude_sickness en.wikipedia.org/wiki/Altitude_sickness Oxygen enrichment or BYOB of O 2 ! Altitude acclimatization –Gradual adjustment to decreasing oxygen level with increasing altitude, which allows for the production of additional red blood cells –Some drugs can accelerate the adjustment Humans can adjust to elevations up to 6000 meters (~20,000 feet = 470 mb).

62. Nepal en.wikipedia.org/wiki/Nepal en.wikipedia.org/wiki/Nepal

63. Temperature (T) Profile More complex than pressure or density Layers based on the Environmental Lapse Rate (ELR), the rate at which temperature decreases with height. inversion isothermal 6.5 o C/km Ahrens, Fig. 1.7

64. Higher Atmosphere Molecular Composition Homosphere- gases are well mixed. Below 80 km. Emphasis of Course. Heterosphere- gases separate by molecular weight, with heaviest near bottom. Lighter gases (H, He) escape. Ahrens, Fig. 1.8

65. Atmospheric Layers Essentials Thermosphere-above 85 km Temps warm w/height Gases settle by molecular weight (Heterosphere) Mesosphere-50 to 85 km Temps cool w/height Stratosphere-10 to 50 km Temps warm w/height, very dry Troposphere-0 to 10 km (to the nearest 5 km) Temps cool with height Contains “all” H 2 O vapor, weather of public interest

66. Take Home Points Many gases make up air N 2 and O 2 account for ~99% Trace gases: CO 2, H 2 O, O 3, etc. Can be very important…more later Pressure and Density Profiles Decrease rapidly with height Temperature Profile Complex vertical structure

67. Climate and Weather “Climate is what you expect. Weather is what you get.” -Robert A. Heinlein

68. Weather Weather – The state of the atmosphere: for a specific place at a particular time Weather Elements 1) Temperature 2) Pressure 3) Humidity 4) Wind 5) Visibility 6) Clouds 7) Significant Weather

69. Surface Station Model Temperatures Plotted  F in U.S. Sea Level Pressure Leading 10 or 9 is not plotted Examples: 1013.8 plotted as 138 998.7 plotted as 987 1036.0 plotted as 360 Ahrens, p 431 Responsible for boxed parameters

70. Sky Cover and Weather Symbols Ahrens, p 431

71. Pressure Tendency Change in pressure over the past 3 hours is also plotted. Also called barometric tendency Ahrens, p 432

72. Wind Barbs Direction Wind is going towards Westerly Westerly  from the West Speed (accumulated) Each flag is 50 knots Each full barb is 10 knots Each half barb is 5 knots Ahrens, p 432 65 kts from west

73. temperature dew point SLP pressure wind cloud cover Ohio State website

74. Practice Surface Station Temperate ( o F) Pressure (mb) Last Three Digits (tens, ones, tenths) Dew Point (later) Moisture Wind Barb Direction and Speed Cloud Cover Tenths total coverage Ahrens, p 431 72 58 111 Decimal point What are Temp, Dew Point, SLP, Cloud Cover, Wind Speed and Direction?

75. Practice Surface Station Sea Level Pressure Leading 10 or 9 is not plotted Examples: 1013.8 plotted as 138 998.7 plotted as 987 1036.0 plotted as 360 Ahrens, p 431 42 18 998 Decimal point What are Temp, Dew Point, SLP, Cloud Cover, Wind Speed and Direction?

76. Surface Map Symbols Fronts Mark the boundary between different air masses…later Significant weather occurs near fronts Current US Map Ahrens, p 432

78. Radiosonde Weather balloons, or radiosondes, sample atmospheric to 10 mb. They measure temperature moisture pressure They are tracked to get winds Ahrens, Fig. 1

79. Radiosonde Distribution Radiosondes released at 0000 and at 1200 GMT for a global network of stations. Large gaps in network over oceans and in less affluent nations. Stations ~400 km apart over North America

80. Radiosonde for Tucson Example of data taken by weather balloon released over Tucson Temperature (red) Moisture (green) Winds (white) Note variations of all fields with height UA Tucson 1200 RAOB troposphere stratosphere tropopause temperature profile moisture profile wind profile

81. Upper-Air Model Conditions at specific pressure level Wind Temperature (  C) Moisture (Later) Height above MSL UA 500mb Analysis Ahrens, p 427 Ahrens, p 431 Responsible for boxed parameters