1 / 267

Cloud Physics

Cloud Physics. What is a cloud?. Cloud Physics. What is a cloud? Water droplets or ice crystals in the air. Cloud Physics. What is a cloud? Water droplets or ice crystals in the air. Why important?. Cloud Physics. What is a cloud? Water droplets or ice crystals in the air.

alima
Download Presentation

Cloud Physics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cloud Physics • What is a cloud?

  2. Cloud Physics • What is a cloud? • Water droplets or ice crystals in the air.

  3. Cloud Physics • What is a cloud? • Water droplets or ice crystals in the air. • Why important?

  4. Cloud Physics • What is a cloud? • Water droplets or ice crystals in the air. • Why important? • Precipitation • Solar radiation

  5. Cloud Physics • What is a cloud? • Water droplets or ice crystals in the air. • Why important? • Precipitation • Solar radiation • What do we want to learn? • Formation of clouds • Development of precipitation

  6. Cloud Physics • What is a cloud? • Water droplets or ice crystals in the air. • Why important? • Precipitation • Solar radiation • What do we want to learn? • Formation of clouds • Development of precipitation • Methods?

  7. Cloud Physics • What is a cloud? • Water droplets or ice crystals in the air. • Why important? • Precipitation • Solar radiation • What do we want to learn? • Formation of clouds • Development of precipitation • Methods? • Cloud microphysics • Cloud dynamics

  8. Cloud Physics • Understanding the properties of clouds • What clouds are (why are they different) • How they develop in time • How they interact and affect the energy balance of the planet • Development of precipitation, rain, hail, and snow • Role in general circulation of the atmosphere

  9. Cloud Physics • Understanding the properties of clouds • What clouds are (why are they different) • How they develop in time • How they interact and affect the energy balance of the planet • Development of precipitation, rain, hail, and snow • Role in general circulation of the atmosphere • These subjects are important to • Radar meteorology • Weather modification • Severe storms research • Global energy balance (greenhouse effect)

  10. Overview • Thermodynamics of dry air • Water vapor and its thermodynamic effects • Parcel buoyancy and atmospheric stability • Mixing and convection • Observed properties of clouds • Formation of cloud droplets • Droplet growth by condensation • Initiation of rain • Formation and growth of ice crystals • Severe weather

  11. Atmospheric composition

  12. Atmospheric composition • Permanent gases • Variable gases • Aerosols

  13. Atmospheric composition • Permanent gases • Nitrogen, oxygen, argon, neon, helium, etc. • Variable gases • Water vapor, carbon dioxide, and ozone. • Aerosols • Smoke, dust, pollen, and condensed forms of water (hydrometeors).

  14. Review • Zeroth law of thermodynamics

  15. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law

  16. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law •  /T = R/p = f(p) • Define temperature, K = ?

  17. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law •  /T = R/p = f(p) • Define temperature, K = ? • Boyle’s Law

  18. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law •  /T = R/p = f(p) • Define temperature, K = ? • Boyle’s Law • p  = RT = g(T) • Avogadro’s law (ideal gas)

  19. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law •  /T = R/p = f(p) • Define temperature, K = ? • Boyle’s Law • p  = RT = g(T) • Avogadro’s law (ideal gas) • p  /T = R* / m =R (for individual gas or R’ for dry air) • m: molecular weight = ?

  20. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law •  /T = R/p = f(p) • Define temperature, K = ? • Boyle’s Law • p  = RT = g(T) • Avogadro’s law (ideal gas) • p  /T = R* / m • m: molecular weight = ? • 1st law of thermodynamics

  21. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law •  /T = R/p = f(p) • Define temperature, K = ? • Boyle’s Law • p  = RT = g(T) • Avogadro’s law (ideal gas) • p  /T = R* / m =R (for individual gas or R’ for dry air) • m: molecular weight = ? • 1st law of thermodynamics • dq = du + dw = du + p d = dh - dp • Work-heat relation (1 cal = ? J)

  22. Review • Zeroth law of thermodynamics • Concept of thermometer • Charles’ Law •  /T = R/p = f(p) • Define temperature, K = ? • Boyle’s Law • p  = RT = g(T) • Avogadro’s law (ideal gas) • p  /T = R* / m =R (gas constant for individual gas or R’ for dry air ) • m: molecular weight = ? • 1st law of thermodynamics • dq = du + dw = du + p d = dh - dp • Work-heat relation (1 cal = ? J) • Dalton’s law

  23. Review, cont. • Specific heats:

  24. Review, cont. • Specific heats: c = dq/dT • cv =(q/T) • cp= ( q/T)p • cp = cv + R

  25. Review, cont. • Specific heats: c = dq/dT • cv =(q/T) • cp= ( q/T)p • cp = cv + R • Equipartition of energy

  26. Review, cont. • Specific heats: c = dq/dT • cv =(q/T) • cp= ( q/T)p • cp = cv + R • Equipartition of energy • degree of freedom: f • u = fRT/2

  27. Review, cont. • Specific heats: c = dq/dT • cv =(q/T) • cp= ( q/T)p • cp = cv + R • Equipartition of energy • degree of freedom: f • u = fRT/2 • Entropy (3 meanings)

  28. Review, cont. • Specific heats: c = dq/dT • cv =(q/T) • cp= ( q/T)p • cp = cv + R • Equipartition of energy • degree of freedom: f • u = fRT/2 • Entropy • d = dq/T • Irreversible processes: entropy change is defined by that in reversible processes.

  29. Review, cont. • Specific heats: c = dq/dT • cv =(q/T) • cp= ( q/T)p • cp = cv + R • Equipartition of energy • degree of freedom: f • u = fRT/2 • Entropy • d = dq/T • Irreversible processes: entropy change is defined by that in reversible processes. • 2nd law of thermodynamics

  30. Review, cont. • Specific heats: c = dq/dT • cv =(q/T) • cp= ( q/T)p • cp = cv + R • Equipartition of energy • degree of freedom: f • u = fRT/2 • Entropy • d = dq/T • Irreversible processes: entropy change is defined by that in reversible processes. • 2nd law of thermodynamics • d system + d environment 0.

  31. Review: Processes Isochoric:

  32. Review: Processes Isochoric: dq = du, dq = cv dT Isobaric:

  33. Review: Processes Isochoric: dq = du, dq = cv dT Isobaric: pV0 = const, dq = cp dT Isothermal:

  34. Review: Processes Isochoric: dq = du, dq = cv dT Isobaric: pV0 = const, dq = cp dT Isothermal: pV1 = const, du = 0, dq = -  dp = pd = dw Adiabatic:

  35. Review: Processes Isochoric: dq = du, dq = cv dT Isobaric: pV0 = const, dq = cp dT Isothermal: pV1 = const, du = 0, dq = -  dp = pd = dw Adiabatic: pV = const, dq = 0 cp dT =  dp, cv dT =- pd where  = cp / cv = 1+2/f Polytropic:

  36. Review: Processes Isochoric: dq = du, dq = cv dT Isobaric: pV0 = const, dq = cp dT Isothermal: pV1 = const, du = 0, dq = -  dp = pd = dw Adiabatic: pV = const, dq = 0 cp dT =  dp, cv dT =- pd where  = cp / cv = 1+2/f Polytropic: pVn = const. (adiabatic) Free expansion:

  37. Review: Processes Isochoric: dq = du, dq = cv dT Isobaric: pV0 = const, dq = cp dT Isothermal: pV1 = const, du = 0, dq = -  dp = pd = dw Adiabatic: pV = const, dq = 0 cp dT =  dp, cv dT =- pd where  = cp / cv = 1+2/f Polytropic: pVn = const. (adiabatic) Free expansion: q= u= T = 0, 0

  38. Review: Processes Isochoric: dq = du, dq = cv dT Isobaric: pV0 = const, dq = cp dT Isothermal: pV1 = const, du = 0, dq = -  dp = pd = dw Adiabatic: pV = const, dq = 0 cp dT =  dp, cv dT =- pd where  = cp / cv = 1+2/f Polytropic: pVn = const. (adiabatic) Free expansion: q= u= T = 0, 0 Homework: 1.1, 1.2, and 1.3, 1.5* due on ?

  39. Diagrams P-V diagram:

  40. Diagrams • P-V diagram: work pd,

  41. Diagrams • P-V diagram: work pd, • u: state function, remains same in a cycle. • ∮dw=∮𝑑𝑞.

  42. Diagrams • P-V diagram: work pd, • u: state function, remains same in a cycle. • ∮dw=∮𝑑𝑞. • P-T diagram:

  43. Diagrams P-V diagram: work pd, u: state function, remains same in a cycle. ∮dw=∮𝑑𝑞. P-T diagram: Where is each state, triple point phase transitions.

  44. Diagrams P-V diagram: work pd, u: state function, remains same in a cycle. ∮dw=∮𝑑𝑞. P-T diagram: Where is each state, triple point phase transitions. e- diagram:

  45. Diagrams • P-V diagram: work pd, • u: state function, remains same in a cycle. • ∮dw=∮𝑑𝑞. • P-T diagram: • Where is each state, triple point • phase transitions. • e- diagram: • e: vapor pressure • phase transitions, isotherm.

  46. Diagrams • P-V diagram: work pd, • u: state function, remains same in a cycle. • ∮dw=∮𝑑𝑞. • P-T diagram: • Where is each state, triple point • phase transitions. • e- diagram: • e: vapor pressure • phase transitions, isotherm. • Stüve (p –T) diagram: adiabatic • T/ = (p/1000mb) , potential temp, =R/cp

  47. Diagrams • P-V diagram: work pd, • u: state function, remains same in a cycle. • ∮dw=∮𝑑𝑞. • P-T diagram: • Where is each state, triple point • phase transitions. • e- diagram: • e: vapor pressure • phase transitions, isotherm. • Stüve (p –T) diagram: adiabatic • T/ = (p/1000mb) , potential temp, =R/cp • Diagrams: area of a closed path

  48. Diagrams, cont. • Emagram: • Work: V is difficult to measure for a p-V diagram.

  49. Diagrams, cont. • Emagram: • Work: V is difficult to measure for a p-V diagram. • dw = pd = R’dT-  dp = R’dT – R’T dp/p • ∮ dw = -R’ ∮T d(lnp) • energy-per-unit-mass diagram (R’=R*/m)

More Related