School of something FACULTY OF OTHER 1 Lecture 2: Aerosol sources and sinks Ken Carslaw.

Slides:



Advertisements
Similar presentations
What’s Up There May be a Problem, or then again, Maybe Not Now for a Little Information on Aerosols Rosemary Millham, PhD NASA GSFC/SSAI.
Advertisements

BIOGEOCHEMICAL CYCLES Biology 420 Global Change. Introduction  Remember  Lithosphere  Hydrosphere  Atmosphere  Biosphere  Earth is exposed to cyclic.
MATTER CYCLING IN ECOSYSTEMS
Development of a Secondary Organic Aerosol Formation Mechanism: Comparison with Smog Chamber Experiments and Atmospheric Measurements Luis Olcese, Joyce.
Geophysical Fluid Dynamics Laboratory Review June 30 - July 2, 2009 Geophysical Fluid Dynamics Laboratory Review June 30 - July 2, 2009.
VIII. Aerosols Size distribution Formation and Processing Composition Aerosol phase chemistry.
School of Earth and Environment INSTITUTE FOR CLIMATE & ATMOSPHERIC SCIENCE Is the Arctic the most uncertain aerosol environment in the world? Ken Carslaw,
Proposed Aerosol Treatment for CAM4 Steve Ghan, Richard Easter, Xiaohong Liu, Rahul Zaveri Pacific Northwest National Laboratory precursor emissions coagulation.
(Mt/Ag/EnSc/EnSt 404/504 - Global Change) Radiative Forcing (from IPCC WG-I, Chapter 2) Changes in Radiative Forcing Primary Source: IPCC WG-I Chapter.
Aerosols By Elizabeth Dahl (2005) Edited by Ted Dibble (2008)
Some Impacts of Atmospheric Aerosols Direct and Indirect Effects on Climate directly scattering solar radiation altering number and size distribution of.
METO 621 Lesson 24. The Troposphere In the Stratosphere we had high energy photons so that oxygen atoms and ozone dominated the chemistry. In the troposphere.
Mean annual temperature (°F) Mean annual precipitation (inches)
Ultrafine Particles and Climate Change Peter J. Adams HDGC Seminar November 5, 2003.
What are aerosols ? Aerosol is a collection of particles suspended in the air, they range in size from 0.01 microns to several tens of microns.
Implementation of Sulfate and Sea-Salt Aerosol Microphysics in GEOS-Chem Hi everyone. My name is Win Trivitayanurak… I’m a PhD student working with Peter.
Part 5. Human Activities Chapter 14 Human Effects: Air Pollution and Heat Islands.
Chem. 250 – 10/7 Lecture Updated 10/30 Instructor: Roy Dixon My Website for Course:
Nucleation: Formation of Stable Condensed Phase Homogeneous – Homomolecular H 2 O (g)  H 2 O (l) Homogeneous – Heteromolecular nH 2 O (g) + mH 2 SO 4(g)
METO 637 Lesson 13. Air Pollution The Troposphere In the Stratosphere we had high energy photons so that oxygen atoms and ozone dominated the chemistry.
METO 637 Lesson 16.
Illumination Independent Aerosol Optical Properties n Extinction Scattering Absorption n Volume scattering function (phase) n Transmittance.
The Weekend Effect Does it really exist in surface temperature and if so, what is the cause? David Ridley (Ken Carslaw and Martyn Chipperfield)
This Week—Tropospheric Chemistry READING: Chapter 11 of text Tropospheric Chemistry Data Set Analysis.
Aerosols and climate Rob Wood, Atmospheric Sciences.
Aerosols. Atmospheric Aerosols Bibliography Seinfeld & Pandis, Atmospheric Chemistry and Physics, Chapt Finlayson-Pitts & Pitts, Chemistry of the.
The Role of Aerosols in Climate Change Eleanor J. Highwood Department of Meteorology, With thanks to all the IPCC scientists, Keith Shine (Reading) and.
Typically have a higher organic content than coarse particles Also contain soluble inorganics: NH 4 +, NO 3 -, SO 4 2- A bimodal peak is often observed.
What is Particulate Matter and How does it Vary? What is Particulate Matter? How Does PM Vary? The Influence of Emissions, Dilution and Transformations.
Modeling BC Sources and Sinks - research plan Charles Q. Jia and Sunling Gong University of Toronto and Environment 1 st annual NETCARE workshop.
Chem. 253 – 2/18 Lecture. Announcements I Return HW Group assignment HW 1.2 – some needed to show work (e.g. conversions from molec cm -3 s -1 to.
1 1 Model studies of some atmospheric aerosols and comparisons with measurements K. G e o r g i e v I P P – B A S, S o f i a, B u l g a r i a.
QUESTIONS 1.Is the rate of reaction of S(IV) more likely to be slower than calculated for a cloud droplet or a rain droplet? Why? 2.If you wanted to determine.
Climate Changes and Anthropogenic Influences ATM 100.
AIR POLLUTION. any adverse change in the composition of Earth's atmosphere as a consequence of it different gases, water vapor and particulate matter.
Aim: What are the major outdoor air pollutants?
FROM AIR POLLUTION TO GLOBAL CHANGE AND BACK: Towards an integrated international policy for air pollution and climate change Daniel J. Jacob Harvard University.
Improving Black Carbon (BC) Aging in GEOS-Chem Based on Aerosol Microphysics: Constraints from HIPPO Observations Cenlin He Advisers: Qinbin Li, Kuo-Nan.
Copyright © 2013 Pearson Education, Inc. The Atmosphere: An Introduction to Meteorology, 12 th Lutgens Tarbuck Lectures by: Heather Gallacher, Cleveland.
School of something FACULTY OF OTHER 1 Lecture 1: Introduction Ken Carslaw.
Environmental chemistry Environmental chemistry air pollution Option E in Paper 3 study of the effect of human activity on the chemical processes in the.
Properties of Particulate Matter Physical, Chemical and Optical Properties Size Range of Particulate Matter Mass Distribution of PM vs. Size: PM10, PM2.5.
Biosphere/Atmosphere Interactions in the Tropics.
Atmosphere and Air Pollution Chapter 18. Quick Recap.
Progress on Application of Modal Aerosol Dynamics to CAM Xiaohong Liu, Steve Ghan, Richard Easter, Rahul Zaveri, Yun Qian (Pacific Northwest National.
Modeling of aerosol processes in the atmosphere Peter Tunved Department of Environmental Science and Analytical Chemistry Stockholm University Sweden.
GLOBAL SULFUR BUDGET [Chin et al., 1996] (flux terms in Tg S yr -1 ) Phytoplankton (CH 3 ) 2 S SO 2  1.3d DMS  1.0d OHNO 3 Volcanoes Combustion.
The GEOS-CHEM Simulation of Trace Gases over China Li ZHANG and Hong LIAO Institute of Atmospheric Physics Chinese Academy of Sciences April 24, 2008.
Gas and Aerosol Partitioning Over the Equatorial Pacific Wenxian Zhang April 21, 2009.
Linking Anthropogenic Aerosols, Urban Air Pollution and Tropospheric Chemistry to Climate ( actually, to CAM/CCSM ) Chien Wang Massachusetts Institute.
1.
Carbonaceous aerosols – a global modeling view Betty Croft and Ulrike Lohmann * Department of Physics and Atmospheric Science Dalhousie University, Halifax,
Urban Heat Island and Pollution
 QUIZ…how well are we reading.  “Pollution is nothing but the resources we are not harvesting. We allow them to disperse because we’ve been ignorant.
OVERVIEW OF ATMOSPHERIC PROCESSES: Daniel J. Jacob Ozone and particulate matter (PM) with a global change perspective.
K.S Carslaw, L. A. Lee, C. L. Reddington, K. J. Pringle, A. Rap, P. M. Forster, G.W. Mann, D. V. Spracklen, M. T. Woodhouse, L. A. Regayre and J. R. Pierce.
AT737 Aerosols.
Aerosols and climate - a crash course Marianne T. Lund CICERO Nove Mesto 17/9-15.
An Interactive Aerosol-Climate Model based on CAM/CCSM: Progress and challenging issues Chien Wang and Dongchul Kim (MIT) Annica Ekman (U. Stockholm) Mary.
I. I.Climate Change – Greenhouse Gases A. A.Background Greenhouse Effect Gases absorb heat (not light) Natural Greenhouse Effect Mean planetary temperature.
04/12/011 The contribution of Earth degassing to the atmospheric sulfur budget By Hans-F. Graf, Baerbel Langmann, Johann Feichter From Chemical Geology.
NATS 101 Lecture 1 Atmospheric Composition. 100 km a  6500 km C = 2  a  x 10 4 km Ratio: Height/ Length is 100/(4.084 x 10 4 )  2.45 x
AN ATMOSPHERIC CHEMIST’S VIEW OF THE WORLD FiresLand biosphere Human activity Lightning Ocean physics chemistry biology.
Understanding The Effect Of Anthropogenic Aerosol Weekly Cycles Upon The Climate Using A Global Model Of Aerosol Processes (GLOMAP) Introduction GLOMAP.
METO 621 CHEM Lesson 4. Total Ozone Field March 11, 1990 Nimbus 7 TOMS (Hudson et al., 2003)
AIR POLLUTION. Pollutants VOCs=volatile organic compounds: chemicals used to manufacture and maintain building materials, interior furnishing, cleaning.
Properties of Particulate Matter
Modal Aerosol Treatment in CAM: Evaluation and Indirect Effect X. Liu, S. J. Ghan, R. Easter (PNNL) J.-F. Lamarque, P. Hess, N. Mahowald, F. Vitt, H. Morrison,
Dr. Tanveer Iqbal Associate Professor,
大气圈地球化学及其环境效益.
Presentation transcript:

School of something FACULTY OF OTHER 1 Lecture 2: Aerosol sources and sinks Ken Carslaw

2 Key issues What are the relative source strengths and distributions? How quickly is aerosol produced and removed? How do these factors change with particle size? Following lecture: how are aerosol properties altered between emission and removal?

3 Primary and secondary particles Primary particles are emitted directly into the atmosphere Secondary particles are formed in the atmosphere (by condensation or nucleation of gaseous precursors). One person’s primary is another’s secondary E.g., global model: urban particles may be treated as primary because they are formed below the grid scale. I.e., they can be primary if formed within a source (e.g., an engine, city, etc.)

4 Primary, Secondary and Aged Primary Primary particles Secondary particles Emitted gases gases coagulation condensation Aged primary particles Can contain primary and secondary matter chemistry Source ACPD Discussion by U. Poeschl: Amusing article on definitions: Schwartz, Henry’s law and sheep’s tails, Atmospheric environment, 22, , Reply: Clegg and Brimblecombe, p

5 Primary and secondary emissions Primary Dust (including re-suspended), combustion products of elemental and organic carbon (biomass burning, wildfires, vehicles), sea spray, primary biological particles (spores, etc) Secondary Ammonia  ammonium (dissolution) SO 2, Dimethyl sulfide  oxidation  sulfate (H 2 SO 4 ) Nitrogen oxides  oxidation  nitrate (HNO 3 ) Volatile organic compounds (VOCs) -> oxidation -> low vapor pressure organic products (secondary organic aerosol, SOA) From natural and anthropogenic sources

6 Quantifying emissions Active emissions (Depend on the environment) Sea spray, dust – wind speed DMS – wind speed and biological activity etc. Biogenic VOCs – temperature, biological activity Passive emissions (Depend on emission factors, energy use, etc) Anthropogenic NO x, SO 2, black carbon

7 Sulfur dioxide Domestic 9 Tg/a Power plants 48 Tg/a Industry 39 Tg/a Volcanic SO 2 = Tg/a Biogenic equiv SO 2 = 36Tg/a SO 2 (m=64)  H 2 SO 4 (m=98) Dimethyl sulfide

8 Organic matter Biomass burning = 34Tg/aFossil fuel 3Tg/a Biofuel = 9Tg/a Biogenic SOA = 10 – 100’s Tg/a (see Donahue)

9 Sea spray Global sea spray mass production rate Total = 8000 Tg/a

10 Sea spray size distribution Marine aerosol production: a review of the current knowledge, O'Dowd and De Leeuw, Phil Trans Roy Soc A, 365, 2007 Wind speed = 8 m/s Number, area, volume ~1.3% of sea spray is in the accumulation mode ~ 100 Tg/a

11 Biomass burning size distribution dN/dlogD from lognormal fitting

12 Traffic emissions size distribution nm nm ~80 nm Putaud et al, Aerosol Phenomenology, 2003 Rural UrbanKerbside

13 Aerosol production / emission rates

14 Sea spray flux versus wind speed Flux is proportional to 10 m wind speed cubed

15 Sea spray production rates Integrated flux in a size range At nm: Mean concentration after one day N nm ~ 350 cm -3 N 1  m ~ 3.5 cm -3 F 1 km 1 m 2 Assume steady flux into 1 km deep well mixed boundary layer with u = 8 ms -1

16 Secondary aerosol production rates SO 2 + OH + M  H 2 SO 4 k OH ~ cm 3 molec -1 s -1 OH ~ 10 6 molec cm -3 SO 2 gas phase chemical lifetime ~ 10 6 s ~ 10 days Pham et al., JGR, 1995 * see Donahue! NO 2 + OH  HNO 3 NO 2 lifetime ~ 1 day OH+  -pinene  organic aerosol * k OH = 1.2×10 −11 exp(444/T) Monoterpene lifetime ~ 0.4 days

17 Sulfate aerosol production in clouds SO 2 evaporation cloud Involatile H 2 SO 4 remains in particles SO 2 H 2 SO 4 (gas) H 2 SO 4 (particles) deposition 42 ~4 times as much SO 4 from clouds as from gas phase oxidation: SO 2 lifetime ~ 2.5 days + OH

18 Aerosol removal (scavenging) processes Dry deposition – diffusion to and deposition on surface Wet deposition In-cloud or “nucleation” scavenging Impaction

19 Dry deposition Deposition velocity over forest 10 cm s -1  lifetime of 1 km deep well mixed boundary layer aerosol ~ 3h 0.1 cm s -1  lifetime of ~12 days Brownian diffusion Gravitational settling 1 m/s 20 m/s Accumulation mode!

20 Wet scavenging In-cloud scavenging Below-cloud scavenging

21 Wet scavenging Characteristic time scale for the conversion of cloud droplets into raindrops in precipitating clouds ~ 3 hours PROBLEMS: Cloud-scale processes Particle size dependence In-cloud scavenging

22 Wet scavenging Below-cloud scavenging 3nm: h 10  m: h 100nm: 10days-weeks

23 Global aerosol production and loss timescales

24 Production of global aerosol mass ~1 month to reach steady state Based on Leeds GLOMAP global aerosol model

25 Decay of global aerosol mass and number Mass lifetime ~ 3 days 10% remains after 1 month Arctic Number lifetime ~ 10 days Switch off all emission processes in a global model Global models predict a ~factor 2 difference in aerosol lifetime between US, Asia & Europe Based on Leeds GLOMAP global aerosol model

26 Importance of aerosol lifetime It is short compared to most greenhouse gases CO 2 – 100 y CH 4 – 11y Aerosols do not accumulate in the atmosphere In the long term can expect GHGs to dominate forcing

27 Pb 210 tracer to quantify deposition lifetimes Huge model diversity in remote regions due to differences in deposition Rasch et al., Tellus, 2000