ATM 507 Lecture 5. Text reading Chapter 4 Problem Set #2 due Sept. 20 Today s topics Photochemistry and Photostationary State Relation
|
|
- Mildred Powell
- 5 years ago
- Views:
Transcription
1 ATM 507 Lecture 5 Text reading Chapter 4 Problem Set #2 due Sept. 20 Today s topics Photochemistry and Photostationary State Relation
2 Beer-Lambert Law (for the absorption of light) Used to describe the absorption of light passing through a moderately weak absorber. I(λ) = I 0 (λ) exp{-(abs. coeff.)(conc.)(path length)} Formulation from Chemistry textbooks log 10 (I 0 /I) = ε C l I 0 = incident monochromatic (or narrow) intensity I = transmitted intensity ε = molar extinction coefficient (base 10) = ε(λ, T, C) C = concentration (moles li -1 or M) l = absorption pathlength in cm
3 Beer-Lambert Law (cont.) Gas Phase Absorption (pressure units) I = I 0 exp (-k p l ) or ln(i 0 /I) = k p l k = absorption coefficient in atm -1 cm -1 p = absorber partial pressure in atm Gas Phase Absorption (absolute units) I = I 0 exp (-σ N l ) or ln(i 0 /I) = σ N l σ = absorption cross-section in cm 2 molecule -1 N = absorber density in molecules cm -3 For a mixture of gases I = I 0 exp [-(σ 1 N 1 + σ 2 N 2 + σ 3 N 3 + ) l ]
4 Absorption by a Thin Layer of Gas At one wavelength I absorbed = I 0 I = I 0 { 1 exp(- σ N l ) } Absorption = A = (I o I)/I o = 1 exp(- σ N l ) Look at a Taylor series expansion of 1 exp(- σ N l ) 1 exp(- σ N l ) = σ N l - (σ N l ) 2 /2! +(σ N l ) 3 /3! - For small values of (σ N l) keep only the first term I a I 0 (σ N l ) How much error is introduced by this approximation? Optical Depth (σ N l ) % error
5 Thin Layer Absorption (cont.) The approximate expression links the absorbed light to the incident light and absorption cross-section ( and N and l). If we consider a thin layer, the light absorbed per unit length is (# photons absorbed) cm -3 s -1 = I a / l = I 0 σ N l / l = I 0 (λ) σ(λ) N If we identify I 0 (λ) as the Actinic Flux F λ (this is the flux at one wavelength no dependence on wavelength interval) I abs = F λ σ(λ) N Light absorbed per unit volume per unit time = Spherically Integrated Actinic flux x Absorption Crosssection x Concentration Photons cm -3 s -1 = Photons cm -2 s -1 x cm 2 molecule -1 x molecules cm -3 These absorbed photons are the ones capable of producing the chemical change we are interested in.
6 Photodissociation Reactions described as Rate Expressions A + h (A*) B + C -da/dt = k phot [A] k phot = photolysis or photodissociation rate constant depends on F(λ), σ(λ), Φ(λ), etc. Recall that I abs = F λ σ(λ) [A] at wavelength λ This expression considers all absorbed photons if we restrict our consideration to only the photons effective for a particular process, the quantum yield is added to the equation I abs = F λ σ(λ) Φ(λ) [A]
7 Photolysis Rate Constants If the expression for I abs is integrated over wavelength, the result is a photolysis rate expression (Rate expression) = (Integral of all photons that cause reaction) k phot [A] = F(λ) σ(λ) Φ(λ) d λ [A]; or k phot = F(λ) σ(λ) Φ(λ) d λ If the quantities F, σ, and Φ are not available in functional form, but are from a table, one can approximate the integral by a sum λ k p = (F λ σ(λ) Φ(λ)) {or k p = (F(λ) σ(λ) Φ(λ) Δλ} These are important results the second form is used in Problem set #3 K p is a first order rate constant with units (time) -1. λ
8 Chemical Compounds found in the Troposphere which Absorb Sunlight ( = nm) NO 2 (Fig. 4.16), NO 3, O 3 (Fig. 4.13), SO 2 Nitrites HONO, RONO Aldehydes H 2 CO, Ketones & dicarbonyls acetone, glyoxal, Nitrates HONO 2, RONO 2, (PAN) Peroxides H 2 O 2, ROOH, ROOR, (PAN) Polynuclear Aromatics* Aerosols* For most of these species, at least some absorption events cause dissociation the exceptions are marked with an *.
9 Chemical Compounds which are not significant absorbers in the UV-visible ( = nm) NO N 2 H 2 O CO and CO 2 H 2 SO 4 Alkanes (parafins) Alkenes (olefins) Alcohols Organic Acids
10 Absorption Spectrum of NO2
11 Quantum Yield for NO 2 +hv NO + O 400 nm
12 Calculated and Measured kp for NO2
13 Absorption Spectrum of NO3
14 Photochemical Reactions in the Atmosphere Consider perhaps the central reaction cycle for tropospheric chemistry: NO 2 + hv NO + O; k min -1 (depends on sun) O + O 2 + M O 3 + M; k = 6x10-34 cm 6 molecule -2 s -1 NO + O 3 NO 2 + O 2 ; k = 1.9x10-14 cm 3 molecule -1 s -1 (Know these reactions and understand this analysis thoroughly!) NO 2 photolysis is the major source of O 3 production in the troposphere (the other major source is transport from the stratosphere this transported O 3 provides the bulk of the tropospheric background ozone ). The species involved are NO, NO 2, O, O 2, O 3, and M where M is an air molecule, [M] is the air concentration, and [O 2 ] 0.21 [M]
15 Reaction Rates R 1 = k 1 *[NO 2 ] R 2 = k 2 *[O]*[O 2 ]*[M] R 3 = k 3 *[NO]*[O 3 ] NO 2 is produced in reaction 3 and lost in reaction 1 NO is produced in reaction 1 and lost on reaction 3 O 3 is produced in reaction 2 and lost in reaction 3 O is produced in reaction 1 and lost in reaction 2
16 For each species we can write an equation of the form: d[species]/dt = Production Loss = P - L where Production is the combined rate of all production reactions, and Loss is the combined rate of all loss reactions. 1. d[no 2 ]/dt = -k 1 [NO 2 ] + k 3 [NO] [O 3 ] 2. d[no]/dt = k 1 [NO 2 ] - k 3 [NO] [O 3 ] = - d[no 2 ]/dt 3. d[o 3 ]/dt = k 2 [O][O 2 ][M] - k 3 [NO] [O 3 ] 4. d[o]/dt = k 1 [NO 2 ] - k 2 [O][O 2 ][M]
17 Steady State Analysis How do we explore the behavior of this (and other) system(s) of reaction-based equations? A common tool is Steady State Analysis, also called Steady State Approximation, or Stationary State Approximation or SSA for short. Since these equations describe time rates of change, it is quite appropriate to look at the chemical lifetimes (reaction lifetimes) of the species involved and make approximations based on the relative time scales that result. For example, in the above set of reactions (system of equations), the chemical lifetime of the oxygen atom is more than 6 orders of magnitude shorter than the chemical lifetimes of NO, NO 2, and O 3. Therefore, as far as NO, NO 2, and O 3 are concerned, O reacts instantaneously that is, as soon as it is produced it reacts away and is lost. We can write this as P = L; or Production = Loss in the general equation above. (Of course, this is an approximation and only strictly true for times much longer than the O atom lifetime, but in this case that gives us a lot to work with!)
18 Steady State Analysis (cont.) Put another way, O atom is the most reactive species (by a lot), so we invoke SS on it: d[o] ss /dt = 0 = k 1 [NO 2 ] - k 2 [O][O 2 ][M] or k 2 [O][O 2 ][M] = k 1 [NO 2 ] at SS [O] ss = (k 1 [NO 2 ])/ (k 2 [O 2 ][M]) Plug this result into the equation for d[o 3 ]/dt: d[o 3 ] ss /dt = k 2 [O 2 ][M]{k 1 [NO 2 ]/ k 2 [O 2 ][M]} - k 3 [NO] [O 3 ] = k 1 [NO 2 ] - k 3 [NO] [O 3 ] = - d[no 2 ] ss /dt Combined with our earlier result, this yields d[o 3 ] ss /dt = d[no] ss /dt = -d[no 2 ] ss /dt The only way all three time rates of change can be equal is if they are equal to zero, which means that NO, NO 2 and O 3 are all in steady state. (If only these reactions are occurring, this result must stand!)
19 Photostationary State Relation or Since d[o 3 ]/dt =0, Leighton Relation [ O 3 ] SS k 1 k [ NO 3 2 ] [ NO] SS SS Very important result! Covered in Chapter 6 Tropospheric Chemistry Implications [NO 2 ] increases, or light increases [O 3 ] increases
20 Examine the SSA Look at the numerical lifetimes τ NO2 = 1/k 1 1/(0.5 min -1 ) = 2 min = 120 s τ O = 1/(k 2 [O 2 ] [M]) = {(6x10-34 )(.21)(2.45x10 19 ) 2 } 10-5 s τ O <<< τ NO2 and SSA is justified. Guidelines for SSA 1. Invoke SS for most reactive specie (or species) in a reaction set and solve for other species. 2. If there is any doubt, compare chemical lifetimes to justify SSA. As makes sense from τ NO2 above, with regard to ozone production in the troposphere, if τ A << 1 min, SSA is likely to be okay.
21 SSA Tips and Guidance When faced with a set of equations that have more unknowns than equations, use SSA on the most reactive species: Start by invoking SS for O, OH, HO 2, Cl, etc. (the radical species) If necessary then invoke SS for O 3 and other reactive species like NO 3, etc.
22 The Stratosphere Extends from km to ~ 50 km At 15 km, T K, p 100 mbar [M] 3.4x10 18 molecules cm -3 At 50 km, T K, p 1 mbar [M] 2.64x10 16 molecules cm -3 Positive temperature gradient vertically stable molecules take years to diffuse from bottom to top of the stratosphere Key constituent and focus for our analysis is Ozone
23 Ozone Upper scale Temperature Lower scale
24 Ozone Chemistry Main source region equatorial midstratosphere (Produced by photolysis where the photons are ) Mean transport is poleward and downward greatest concentrations are in the polar lower stratosphere (exclusive of ozone holes, of course!) In the absence of losses, ozone pools in the cold & dark.
25 Ozone source and sink regions; main transport.
26 Dynamical Aspects of Strat-Trop Exchange 2 PVU contour Holton, Reviews of Geophysics, 1995
27 Another Look From Scientific Assessment of Ozone Depletion:1998 (WMO)
28
29 Water Vapor Water vapor is a specie that has a very large change from the troposphere to the stratosphere (i.e., larger than ozone) Troposphere wet (sometimes a percent or more 10,000 + ppmv) Stratosphere dry (a few ppmv) Part of the dryness of the stratosphere has to do with very cold temperatures at the tropopause freeze drying any ascending air.
30 Stratospheric Water Vapor (U2 aircraft- 9/11/1980) Water Vapor Blue Temperature - Red
31 Back to Ozone What do measurements show? Sometimes we want absolute ozone concentrations And sometimes we want to know how much ozone is in the column above a given point
32 Measurement Techniques for Stratospheric O3
33 Zonally Averaged [O 3 ] vs. Altitude
34 hole).
35 Total Ozone Column in Dobson Units
36 Absorption by ozone stops the penetration of potentially harmful UV radiation. Red line corresponds to model calculation of surface radiation if stratospheric ozone was 10% lower.
ATM 507 Lecture 4. Text reading Chapters 3 and 4 Today s topics Chemistry, Radiation and Photochemistry review. Problem Set 1: due Sept.
ATM 507 Lecture 4 Text reading Chapters 3 and 4 Today s topics Chemistry, Radiation and Photochemistry review Problem Set 1: due Sept. 11 Temperature Dependence of Rate Constants Reaction rates change
More information2. Sketch a plot of R vs. z. Comment on the shape. Explain physically why R(z) has a maximum in the atmospheric column.
190 PROBLEMS 10. 1 Shape of the ozone layer Consider a beam of solar radiation of wavelength λ propagating downward in the vertical direction with an actinic flux I at the top of the atmosphere. Assume
More information10. Stratospheric chemistry. Daniel J. Jacob, Atmospheric Chemistry, Harvard University, Spring 2017
10. Stratospheric chemistry Daniel J. Jacob, Atmospheric Chemistry, Harvard University, Spring 2017 The ozone layer Dobson unit: physical thickness (0.01 mm) of ozone layer if compressed to 1 atm, 0 o
More informationChapman. 4. O + O 3 2 O 2 ; k 4 5. NO + O 3 NO 2 + O 2 ; k 5 6. NO 2 + O NO + O 2 ; k 6 7. NO 2 + hν NO + O; k 7. NO X Catalytic.
ATM 507 Lecture 8 Text reading Section 5.7 Problem Set # 2 due Sept. 30 Note: next week class as usual Tuesday, no class on Thursday Today s topics Mid-latitude Stratosphere Lower Stratosphere 1 Let s
More informationCHM 5423 Atmospheric Chemistry Notes on reactions of organics in the troposphere (Chapter 5)
CHM 5423 Atmospheric Chemistry Notes on reactions of organics in the troposphere (Chapter 5) 5.1 Introduction In general, the lifetime of a molecule in the troposphere is governed by a variet of processes.
More informationTopic # 15 OZONE DEPLETION IN THE STRATOSPHERE. see pp in Class Notes
Topic # 15 OZONE DEPLETION IN THE STRATOSPHERE see pp 81-85 in Class Notes [ The Ozone Treaty is ] the first truly global treaty that offers protection to every single human being. ~ Mostofa K. Tolba,
More informationATOC 3500/CHEM 3151 Air Pollution Chemistry Lecture 1
ATOC 3500/CHEM 3151 Air Pollution Chemistry Lecture 1 Note Page numbers refer to Daniel Jacob s online textbook: http://acmg.seas.harvard.edu/publications/ jacobbook/index.html Atmos = vapor + sphaira
More informationTananyag fejlesztés idegen nyelven
Tananyag fejlesztés idegen nyelven Prevention of the atmosphere KÖRNYEZETGAZDÁLKODÁSI AGRÁRMÉRNÖKI MSC (MSc IN AGRO-ENVIRONMENTAL STUDIES) Fundamentals to atmospheric chemical reactions. The stratospheric
More informationf N 2 O* + M N 2 O + M
CHM 5423 Atmospheric Chemistry Problem Set 2 Due date: Thursday, February 7 th. Do the following problems. Show your work. 1) Before the development of lasers, atomic mercury lamps were a common source
More informationMeasurements of Ozone. Why is Ozone Important?
Anthropogenic Climate Changes CO 2 CFC CH 4 Human production of freons (CFCs) Ozone Hole Depletion Human production of CO2 and CH4 Global Warming Human change of land use Deforestation (from Earth s Climate:
More informationOn Stationary state, also called steady state. Lifetimes and spatial scales of variability
On sources and sinks ATOC 3500/CHEM 3151 Week 5-6 Additional Notes February 16/18, 2016 On lifetimes, variability, and models On Stationary state, also called steady state Lifetimes and spatial scales
More informationIntroduction to Atmospheric Photochemistry AOSC 433/633 & CHEM 433 Ross Salawitch
Introduction to Atmospheric Photochemistry AOSC 433/633 & CHEM 433 Ross Salawitch Class Web Site: http://www.atmos.umd.edu/~rjs/class/spr2015 Lecture 9 9 March 2015 1 Chapman Chemistry Production of stratospheric
More informationThe Atmosphere. All of it. In one hour. Mikael Witte 10/27/2010
The Atmosphere All of it. In one hour. Mikael Witte 10/27/2010 Outline Structure Dynamics - heat transport Composition Trace constituent compounds Some Atmospheric Processes Ozone destruction in stratosphere
More informationPROBLEMS Sources of CO Sources of tropospheric ozone
220 PROBLEMS 11. 1 Sources of CO The two principal sources of CO to the atmosphere are oxidation of CH 4 and combustion. Mean rate constants for oxidation of CH 4 and CO by OH in the troposphere are k
More informationPlanetary Atmospheres
Planetary Atmospheres Structure Composition Meteorology Clouds Photochemistry Atmospheric Escape EAS 4803/8803 - CP 20:1 Cloud formation Saturated Vapor Pressure: Maximum amount of water vapor partial
More informationChemistry 471/671. Atmospheric Chemistry III: Stratospheric Ozone Depletion
Chemistry 471/671 Atmospheric Chemistry III: Stratospheric Ozone Depletion 2 The Chapman Mechanism O 2 + hn 2 O( 1 D) O( 1 D) + O 2 + M O 3 + M Exothermic O( 1 D) + O 3 2 O 2 O 3 + hn O( 1 D) + O 2 ( 1
More informationTropospheric OH chemistry
Tropospheric OH chemistry CO Oxidation mechanism: CO + OH CO 2 + H, H + O 2 + M HO 2 + M, HO 2 + NO OH + NO 2 NO 2 + hν (+O 2 ) NO + O 3 Initiation step Propagation Net: CO + 2 O 2 CO 2 + O 3 HO 2 + HO
More informationSpectroscopy & Photochemistry I
Spectroscopy & Photochemistry I Required Reading: FP Chapter 3B, 3C, 4 Required Reading: Jacob Chapter 7 Atmospheric Chemistry CHEM-5151 / ATOC-5151 Spring 2013 Jose-Luis Jimenez Importance of Spectroscopy
More informationOutline. Chemical lifetime. Photochemistry. Ozone chemistry Chapman model Catalytic cycles Ozone hole. Institute of Applied Physics University of Bern
Institute of Applied Physics University of Bern Outline Introduction Chemical reactions between stable molecules are quite slow in planetary s Absorption of solar UV-radiation leads to the production of
More informationUnique nature of Earth s atmosphere: O 2 present photosynthesis
Atmospheric composition Major components N 2 78% O 2 21% Ar ~1% Medium components CO 2 370 ppmv (rising about 1.5 ppmv/year) CH 4 1700 ppbv H 2 O variable Trace components H 2 600 ppbv N 2 O 310 ppbv CO
More informationCONTENTS 1 MEASURES OF ATMOSPHERIC COMPOSITION
i CONTENTS 1 MEASURES OF ATMOSPHERIC COMPOSITION 1 1.1 MIXING RATIO 1 1.2 NUMBER DENSITY 2 1.3 PARTIAL PRESSURE 6 PROBLEMS 10 1.1 Fog formation 10 1.2 Phase partitioning of water in cloud 10 1.3 The ozone
More informationClO + O -> Cl + O 2 Net: O 3 + O -> O 2 + O 2
Lecture 36. Stratospheric ozone chemistry. Part2: Threats against ozone. Objectives: 1. Chlorine chemistry. 2. Volcanic stratospheric aerosols. 3. Polar stratospheric clouds (PSCs). Readings: Turco: p.
More informationTopic # 14 OZONE DEPLETION IN THE STRATOSPHERE
Topic # 14 OZONE DEPLETION IN THE STRATOSPHERE A Story of Anthropogenic Disruption of a Natural Steady State p 77 in Class Notes AN OZONE-RELATED CARTOON: MISCONCEPTION! Q1 Is the depletion of STRATOSPHERIC
More informationCHAPTER 1. MEASURES OF ATMOSPHERIC COMPOSITION
1 CHAPTER 1. MEASURES OF ATMOSPHERIC COMPOSITION The objective of atmospheric chemistry is to understand the factors that control the concentrations of chemical species in the atmosphere. In this book
More informationTEST 1 APCH 211 (2012) Review, Solutions & Feedback
TEST 1 APCH 11 (01) Review, Solutions & Feedback Question 1 What is the concentration of nitrogen in the atmosphere (0 C and 1 atm) in g/l? N in the atmosphere ~ 78% Gas concentration unit s means that
More informationBeer-Lambert (cont.)
The Beer-Lambert Law: Optical Depth Consider the following process: F(x) Absorbed flux df abs F(x + dx) Scattered flux df scat x x + dx The absorption or scattering of radiation by an optically active
More informationPlanetary Atmospheres
Planetary Atmospheres Structure Composition Clouds Meteorology Photochemistry Atmospheric Escape EAS 4803/8803 - CP 17:1 Structure Generalized Hydrostatic Equilibrium P( z) = P( 0)e z # ( ) " dr / H r
More informationRadiation in the atmosphere
Radiation in the atmosphere Flux and intensity Blackbody radiation in a nutshell Solar constant Interaction of radiation with matter Absorption of solar radiation Scattering Radiative transfer Irradiance
More information[16] Planetary Meteorology (10/24/17)
1 [16] Planetary Meteorology (10/24/17) Upcoming Items 1. Homework #7 due now. 2. Homework #8 due in one week. 3. Midterm #2 on Nov 7 4. Read pages 239-240 (magnetic fields) and Ch. 10.6 by next class
More information0. Introduction 0.1 Concept The air / environment (geosphere): Is it a reactor? It s a matter of reactions and transports and mixing!
0. Introduction 0.1 Concept The air / environment (geosphere): Is it a reactor? It s a matter of reactions and transports and mixing! mixing times: vertically lower few kilometers (boundary layer) 1h-1d,
More informationTopic # 13 (cont.) OZONE DEPLETION IN THE STRATOSPHERE Part II
Topic # 13 (cont.) OZONE DEPLETION IN THE STRATOSPHERE Part II A Story of Anthropogenic Disruption of a Natural Steady State p 77-79 in Class Notes REVIEW... Q Is the depletion of STRATOSPHERIC OZONE (in
More informationStratospheric Chemistry Part 1 (Chapter 4, p , , , )
Stratospheric Chemistry Part 1 (Chapter 4, p 155-169, 174-176, 198-222, 231-238) zone Discovery and History The Stratosphere and circulation Chapman Chemistry Catalysts The Controversy The zone Hole International
More informationAT 350 EXAM #1 February 21, 2008
This exam covers Ahrens Chapters 1 and 2, plus related lecture notes Write the letter of the choice that best completes the statement or answers the question. b_ 1. The Earth s atmosphere is currently
More information1. The most important aspects of the quantum theory.
Lecture 5. Radiation and energy. Objectives: 1. The most important aspects of the quantum theory: atom, subatomic particles, atomic number, mass number, atomic mass, isotopes, simplified atomic diagrams,
More informationCHEM/ENVS 380 S14, Midterm Exam ANSWERS 1 Apr 2014
PART- A. Multiple Choice Questions (5 points each): Each question may have more than one correct answer. You must select ALL correct answers, and correct answers only, to receive full credit. 1. Which
More informationAbsorption and scattering
Absorption and scattering When a beam of radiation goes through the atmosphere, it encounters gas molecules, aerosols, cloud droplets, and ice crystals. These objects perturb the radiation field. Part
More informationNAME Student ID No. UNIVERSITY OF VICTORIA. CHEMISTRY 102 Term Test I February 4, 2011
NAME Student ID No. Section (circle one): A01 (Dr. Lipson) A02 (Dr. Briggs) A03 (Dr. Brolo) UNIVERSITY OF VICTORIA Version A CHEMISTRY 102 Term Test I February 4, 2011 Version A This test has two parts:
More informationCHAPTER 2 SPECTROSCOPY AND PHOTOCHEMISTRY
CHAPTER 2 SPECTROSCOPY AND PHOTOCHEMISTRY Photochemical processes play a key role in the chemistry of the Earth s atmosphere. Most important atmospheric reactions begin with molecular photodissiciation,
More informationFundamentals of Atmospheric Radiation and its Parameterization
Source Materials Fundamentals of Atmospheric Radiation and its Parameterization The following notes draw extensively from Fundamentals of Atmospheric Physics by Murry Salby and Chapter 8 of Parameterization
More informationExperimental Methods for the Detection of Atmospheric Trace Gases
Experimental Methods for the Detection of Atmospheric Trace Gases Andreas Hofzumahaus Forschungszentrum Jülich, IEK-8 Literature: D.E. Heard, Analytical Techniques for Atmospheric Measurement, Blackwell
More informationThe Planck Blackbody Equation and Atmospheric Radiative Transfer
The Planck Blackbody Equation and Atmospheric Radiative Transfer Roy Clark Ventura Photonics There appears to be a lot of confusion over the use of the terms blackbody absorption and equilibrium in the
More informationLecture 6 - spectroscopy
Lecture 6 - spectroscopy 1 Light Electromagnetic radiation can be thought of as either a wave or as a particle (particle/wave duality). For scattering of light by particles, air, and surfaces, wave theory
More informationReview of Lectures 9 to 16 AOSC 433/633 & CHEM 433. Ross Salawitch
Review of Lectures 9 to 16 AOSC 433/633 & CHEM 433 Ross Salawitch Class Web Site: http://www.atmos.umd.edu/~rjs/class/spr2015 Review of Problem Set #4 will be held Mon, 13 April 6:30 pm Unfortunately the
More information1. Composition and Structure
Atmospheric sciences focuses on understanding the atmosphere of the earth and other planets. The motivations for studying atmospheric sciences are largely: weather forecasting, climate studies, atmospheric
More informationPlanetary Atmospheres
Planetary Atmospheres Structure Composition Clouds Meteorology Photochemistry Atmospheric Escape EAS 4803/8803 - CP 11:1 Structure Generalized Hydrostatic Equilibrium P( z) = P( 0)e z # ( ) " dr / H r
More informationATOC 3500/CHEM 3151 Week 9, 2016 The Game Changer. Some perspective The British Antarctic Survey The Ozone Hole International Regulations
ATOC 3500/CHEM 3151 Week 9, 2016 The Game Changer Some perspective The British Antarctic Survey The Ozone Hole International Regulations Rowland (1974): The work is going very well, but it may mean the
More informationScience 1206 Unit 2: Weather Dynamics Worksheet 8: Layers of the Atmosphere
Science 1206 Unit 2: Weather Dynamics Worksheet 8: Layers of the Atmosphere The atmosphere has a definite impact upon weather patterns and changes. At one time the atmosphere was once considered to be
More informationLecture 3. Composition and structure of the atmosphere. Absorption and emission by atmospheric gases.
Lecture 3. Composition and structure of the atmosphere. Absorption and emission by atmospheric gases. 1. Structure and composition of the Earth s atmosphere. 2. Properties of atmospheric gases. 3. Basic
More informationTHE EXOSPHERIC HEAT BUDGET
E&ES 359, 2008, p.1 THE EXOSPHERIC HEAT BUDGET What determines the temperature on earth? In this course we are interested in quantitative aspects of the fundamental processes that drive the earth machine.
More informationChemical kinetics in the gas phase
Chemical kinetics in the gas phase Chemical kinetics is the study of the rates of transformation of chemical compounds from reactant species into products. The rate of a reaction is defined to be the rate
More informationSpectrum of Radiation. Importance of Radiation Transfer. Radiation Intensity and Wavelength. Lecture 3: Atmospheric Radiative Transfer and Climate
Lecture 3: Atmospheric Radiative Transfer and Climate Radiation Intensity and Wavelength frequency Planck s constant Solar and infrared radiation selective absorption and emission Selective absorption
More information1. Radiative Transfer. 2. Spectrum of Radiation. 3. Definitions
1. Radiative Transfer Virtually all the exchanges of energy between the earth-atmosphere system and the rest of the universe take place by radiative transfer. The earth and its atmosphere are constantly
More informationLecture 3: Atmospheric Radiative Transfer and Climate
Lecture 3: Atmospheric Radiative Transfer and Climate Solar and infrared radiation selective absorption and emission Selective absorption and emission Cloud and radiation Radiative-convective equilibrium
More informationIntroduction to Electromagnetic Radiation and Radiative Transfer
Introduction to Electromagnetic Radiation and Radiative Transfer Temperature Dice Results Visible light, infrared (IR), ultraviolet (UV), X-rays, γ-rays, microwaves, and radio are all forms of electromagnetic
More informationPHYSICS OF THE SPACE ENVIRONMENT
PHYSICS OF THE SPACE ENVIRONMENT PHYS/EATS 380 Winter 006 Notes Set 6 Ionospheric Electron Densities The D, E, F1 and F Layers With the advent of radio communication in the early part of the last century
More informationEVALUATION OF ATMOSPHERIC PROCESSES FOR OZONE FORMATION FROM VEHICLE EMISSIONS
EVALUATION OF ATMOSPHERIC PROCESSES FOR OZONE FORMATION FROM VEHICLE EMISSIONS by WILLIAM P. L. CARTER STATEWIDE AIR POLLUTION RESEARCH CENTER, and COLLEGE OF ENGINEERING CENTER FOR ENVIRONMENTAL RESEARCH
More informationATOC 3500/CHEM 3152 Week 9, March 8, 2016
ATOC 3500/CHEM 3152 Week 9, March 8, 2016 Hand back Midterm Exams (average = 84) Interaction of atmospheric constituents with light Haze and Visibility Aerosol formation processes (more detail) Haze and
More information1. The vertical structure of the atmosphere. Temperature profile.
Lecture 4. The structure of the atmosphere. Air in motion. Objectives: 1. The vertical structure of the atmosphere. Temperature profile. 2. Temperature in the lower atmosphere: dry adiabatic lapse rate.
More informationStratospheric Ozone Depletion, Regional Ozone, Aerosols: Connections to Climate Change
Stratospheric Ozone Depletion, Regional Ozone, Aerosols: Connections to Climate Change Jeff Gaffney Chemistry Department University of Arkansas at Little Rock DOE Biological and Environmental Science Climate
More informationLecture Outlines PowerPoint. Chapter 16 Earth Science 11e Tarbuck/Lutgens
Lecture Outlines PowerPoint Chapter 16 Earth Science 11e Tarbuck/Lutgens 2006 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the use of instructors
More informationPlanetary Temperatures
Planetary Temperatures How does Sunlight heat a planet with no atmosphere? This is similar to our dust grain heating problem First pass: Consider a planet of radius a at a distance R from a star of luminosity
More informationCHAPTER 8. AEROSOLS 8.1 SOURCES AND SINKS OF AEROSOLS
1 CHAPTER 8 AEROSOLS Aerosols in the atmosphere have several important environmental effects They are a respiratory health hazard at the high concentrations found in urban environments They scatter and
More informationNAME Student No. UNIVERSITY OF VICTORIA. CHEMISTRY 102 Mid-Term Test I February 3, Part II Score Exam results Score
NAME Student No. Section (circle one): A01 (Lipson) A02 (Briggs) A03 (Cartwright) UNIVERSITY OF VICTORIA Version B CHEMISTRY 102 Mid-Term Test I February 3, 2012 Version B This test has two parts: (A Data
More informationNAME Student No. UNIVERSITY OF VICTORIA. CHEMISTRY 102 Mid-Term Test I February 3, Part II Score Exam results Score
NAME Student No. Section (circle one): A01 (Lipson) A02 (Briggs) A03 (Cartwright) UNIVERSITY OF VICTORIA Version A CHEMISTRY 102 Mid-Term Test I February 3, 2012 Version A This test has two parts: (A Data
More informationDISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW UNIVERSITY OF VICTORIA. CHEMISTRY 102 Midterm Test 1 February 1, pm (60 minutes)
SECTION: (circle one): A01 MR (Dr. Lipson) A02 (Dr. Briggs) A03 MWR (Dr. Brolo) NAME Student No. V0 (Please print clearly.) DISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW Version A UNIVERSITY
More informationAn Interpretation of Natural Healing of Ozone Holes
ISSN 2278 0211 (Online) An Interpretation of Natural Healing of Ozone Holes Vasudevan Tachoth Nirvan Industries, Private Industrial Estate, Post Sidco Near Railway Gate, Kuruchi Coimbatore, India Abstract:
More informationLecture 26. Regional radiative effects due to anthropogenic aerosols. Part 2. Haze and visibility.
Lecture 26. Regional radiative effects due to anthropogenic aerosols. Part 2. Haze and visibility. Objectives: 1. Attenuation of atmospheric radiation by particulates. 2. Haze and Visibility. Readings:
More informationEmission Temperature of Planets. Emission Temperature of Earth
Emission Temperature of Planets The emission temperature of a planet, T e, is the temperature with which it needs to emit in order to achieve energy balance (assuming the average temperature is not decreasing
More informationExcited State Processes
Excited State Processes Photophysics Fluorescence (singlet state emission) Phosphorescence (triplet state emission) Internal conversion (transition to singlet gr. state) Intersystem crossing (transition
More informationComposition and structure of the atmosphere. Absorption and emission by atmospheric gases.
Lecture 3. Composition and structure of the atmosphere. Absorption and emission by atmospheric gases. 1. Structure and composition of the Earth s atmosphere. 2. Properties of atmospheric gases. 3. Basic
More informationToday s AZ Daily Star has 2 interesting articles: one on our solar future & the other on an issue re: our state-mandated energy-efficiency plan
REMINDER Water topic film Today s AZ Daily Star has 2 interesting articles: one on our solar future & the other on an issue re: our state-mandated energy-efficiency plan Find out all about solar in Arizona
More informationENVIRONMENTAL STRUCTURE AND FUNCTION: EARTH SYSTEM - Chemistry Of The Atmosphere - I.L. Karol and A.A. Kiselev
CHEMISTRY OF THE ATMOSPHERE I.L. Karol and A.A. Main Geophysical Observatory, St. Petersburg, Russia Keywords: Atmospheric composition, gas phase reactions, heterogeneous reactions, catalytic cycles, lifetime
More informationSection 2: The Atmosphere
Section 2: The Atmosphere Preview Classroom Catalyst Objectives The Atmosphere Composition of the Atmosphere Air Pressure Layers of the Atmosphere The Troposphere Section 2: The Atmosphere Preview, continued
More informationThe Atmosphere. Atmospheric structure
The Atmosphere Atmospheric structure Atmospheric layers defined by changes in temperature Troposphere contains 75% of atmospheric gases; temperature decreases with height Tropopause boundary between troposphere
More informationEarth s Atmosphere. Energy Transfer in the Atmosphere. 3. All the energy from the Sun reaches Earth s surface.
CHAPTER 11 LESSON 2 Earth s Atmosphere Energy Transfer in the Atmosphere Key Concepts How does energy transfer from the Sun to Earth and to the atmosphere? How are air circulation patterns within the atmosphere
More informationThermosphere Part-3. EUV absorption Thermal Conductivity Mesopause Thermospheric Structure Temperature Structure on other planets
Thermosphere Part-3 EUV absorption Thermal Conductivity Mesopause Thermospheric Structure Temperature Structure on other planets Thermosphere Absorbs EUV Absorption: Solar Spectrum 0.2 0.6 1.0 1.4 1.8
More informationSpring 2011: ATM S 558. Course Goals. Course Related Activities. Atmospheric Chemistry MW 9 10:20 in 611 ATG
Spring 2011: ATM S 558 Atmospheric Chemistry MW 9 10:20 in 611 ATG Course Goals This class will provide an overview of atmospheric chemistry and the fundamental underpinnings so that you will be able to:
More informationThe Atmosphere. Chapter Test A. Multiple Choice. Write the letter of the correct answer on the line at the left.
The Atmosphere Chapter Test A Multiple Choice Write the letter of the correct answer on the line at the left. 1. Which of the following describes an example of the atmosphere acting as a system? a. its
More information2. Illustration of Atmospheric Greenhouse Effect with Simple Models
2. Illustration of Atmospheric Greenhouse Effect with Simple Models In the first lecture, I introduced the concept of global energy balance and talked about the greenhouse effect. Today we will address
More informationAtmospheric Sciences 321. Science of Climate. Lecture 6: Radiation Transfer
Atmospheric Sciences 321 Science of Climate Lecture 6: Radiation Transfer Community Business Check the assignments Moving on to Chapter 3 of book HW #2 due next Wednesday Brief quiz at the end of class
More informationP T = P A + P B + P C..P i Boyle's Law The volume of a given quantity of gas varies inversely with the pressure of the gas, at a constant temperature.
CHEM/TOX 336 Winter 2004 Lecture 2 Review Atmospheric Chemistry Gas Chemistry Review The Gaseous State: our atmosphere consists of gases Confined only by gravity force of gas on a unit area is due to the
More informationThe Atmosphere. Topic 3: Global Cycles and Physical Systems. Topic 3: Global Cycles and Physical Systems. Topic 3: Global Cycles and Physical Systems
The Atmosphere 1 How big is the atmosphere? Why is it cold in Geneva? Why do mountaineers need oxygen on Everest? 2 A relatively thin layer of gas over the Earths surface Earth s radius ~ 6400km Atmospheric
More informationUNIVERSITY OF VICTORIA CHEMISTRY 102 Midterm Test 1 January 31, pm (60 minutes) DISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW
Version A UNIVERSITY OF VICTORIA CHEMISTRY 102 Midterm Test 1 January 31, 2014 5-6 pm (60 minutes) Version A DISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW Answer all multiple choice questions
More informationCHE 230S ENVIRONMENTAL CHEMISTRY PROBLEM SET 8 Full Solutions
CHE 230S ENVIRONMENTAL CHEMISTRY PROBLEM SET 8 Full Solutions Easier problems 1) Calculate the maximum wavelength of radiation required to promote dissociation of a) a dinitrogen molecule (127nm) b) a
More informationThe Atmosphere. Composition of the Atmosphere. Section 2
The Atmosphere Earth is surrounded by a mixture of gases known as the Nitrogen, oxygen, carbon dioxide, and other gases are all parts of this mixture. Earth s atmosphere changes constantly as these gases
More informationIt is often given in units of cm -1 : watch out for those unit conversions! (1 cm -1 = 100 m -1, not 0.01 m -1 ).
1 Energy of one quantum of radiation (photon) E = hv h = Planckʼs constant, 6.626 10-34 Js v = frequency of radiation Wave equation: vλ = c c = speed of light, 299 792 485 m/s in vacuum, less in other
More informationStratosphere and Ozone
Stratosphere and Ozone Ozone (Greek, ozein, to smell) O 3 Chapman Mechanism O 2 + hv O + O O + O 3 2O 2 O 3 + hv O 2 + O O + O 2 + M O 3 + M third-body. anything What units are used to report the amount
More informationWednesday, September 8, 2010 Infrared Trapping the Greenhouse Effect
Wednesday, September 8, 2010 Infrared Trapping the Greenhouse Effect Goals to look at the properties of materials that make them interact with thermal (i.e., infrared, or IR) radiation (absorbing and reemitting
More informationCommon Elements: Nitrogen, 78%
Chapter 23 Notes Name: Period: 23.1 CHARACTERISTICS OF THE ATMOSPHERE The atmosphere is a layer of that surrounds the earth and influences all living things. Meteorology is the study of the. WHAT S IN
More informationApplication of IR Raman Spectroscopy
Application of IR Raman Spectroscopy 3 IR regions Structure and Functional Group Absorption IR Reflection IR Photoacoustic IR IR Emission Micro 10-1 Mid-IR Mid-IR absorption Samples Placed in cell (salt)
More informationAnalysis Methods in Atmospheric and Oceanic Science
Analysis Methods in Atmospheric and Oceanic Science AOSC 652 Ordinary Differential Equations Week 12, Day 1 1 Differential Equations are central to Atmospheric and Ocean Sciences They provide quantitative
More informationMonday 9 September, :30-11:30 Class#03
Monday 9 September, 2013 10:30-11:30 Class#03 Topics for the hour Solar zenith angle & relationship to albedo Blackbody spectra Stefan-Boltzman Relationship Layer model of atmosphere OLR, Outgoing longwave
More informationtwo slits and 5 slits
Electronic Spectroscopy 2015January19 1 1. UV-vis spectrometer 1.1. Grating spectrometer 1.2. Single slit: 1.2.1. I diffracted intensity at relative to un-diffracted beam 1.2.2. I - intensity of light
More informationOrganic Compounds - Formation Fate and Impact on Troposphere
Organic Compounds - Formation Fate and Impact on Troposphere i.gensch@fz-juelich.de 2 / 20 Organic Compounds - Formation Fate and Impact on Troposphere i.gensch@fz-juelich.de 2 / 20 Definitions VOC: organic
More informationMath 19a - Reading 8.1 outline for discussion section
Math 9a - Reading 8. outline for discussion section due Monday, February 25, 28. How do you, guys, feel about vectors and matrices? Have you seen such things before? What did you think of the lecture on
More informationLecture 25: Atmosphere & environment
Lecture 25: Atmosphere & environment Read: BLB 18.1 4 HW: BLB 18:9,11,15,29,69 Sup 18:1 3 Know: ozone chemistry chemistry of the lower atmosphere sulfer compounds & acid rain nitrogen oxides & smog check
More informationMaria Kanakidou. Environmental Chemistry and Processes Laboratory, Chemistry Department, University of Crete, Heraklion, Greece
Maria Kanakidou Environmental Chemistry and Processes Laboratory, Chemistry Department, University of Crete, Heraklion, Greece mariak@chemistry.uoc.gr Why ocean should care for atmospheric chemistry? Impact
More informationCH-442. Photochemistry I. Prof. Jacques-E. Moser.
CH-442 Photochemistry I Prof. Jacques-E. Moser http://photochemistry.epfl.ch/pc.html Content PHOTOCHEMISTRY I 1. Basic principles 1.1 Introduction 1.2 Laws of light absorption 1.3 Radiation and molecular
More information2/22/ Atmospheric Characteristics
17.1 Atmospheric Characteristics Atmosphere: the gaseous layer that surrounds the Earth I. In the past, gases came from volcanic eruptions A. Water vapor was a major component of outgassing B. Other gases
More informationChapter 11 Lecture Outline. Heating the Atmosphere
Chapter 11 Lecture Outline Heating the Atmosphere They are still here! Focus on the Atmosphere Weather Occurs over a short period of time Constantly changing Climate Averaged over a long period of time
More information