Transcript Overview of talks - Atmospheric chemistry

Atmospheric Chemistry Division
National Center for Atmospheric Research
NCAR/ACD
Biosphere-Atmosphere Trace Gas Exchange
Alex Guenther
Scientist III
Biosphere-Atmosphere Interactions Group
24-26 October 2001, NSF Review
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
1
Biosphere-atmosphere trace gas exchange,
earth system coupling and human forcing
Air
pollutants
Trace gas
Emission
Chemical
Radiative
Environment balance Physical
O3, NOx, CH4
Environment
RONO2 , OH,
N2O, CO, CO2
Trace gas
Temper., Human
deposition
Activities
light
Biosphere
Landcover
change
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
2
Days
Hours
• Regional/global modeling
Satellite derived
estimates of global
distributions
• Model evaluation
• Process
studies
Tower-based
flux meas.
systems
Enclosure
flux meas.
systems
Aircraft and
blimpbased flux
measureme
nt systems
Seconds
TIME SCALE
Years
Trace Gas Flux Studies
Leaf
Canopy
Landscape
Analysis using
ambient
concentrations,
isotopes and
oxidation
products
Regional/global
SPATIAL SCALE
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
3
Research Activities and Products
Instrument
Development
Tools for Universities and Others
Flux Measurement Systems
Flux
Measurements
Database and
Algorithm
Development
and Evaluation
Alex Guenther
Measurement Database
Emission Inventories
(IGAC-GEIA)
Emission Models
(BEIS/GLOBEIS)
Coupled Models
(CCSM, WRF)
Biosphere-Atmosphere Trace Gas Exchange
4
Flux System Development and
Technology Transfer
Enclosure Systems
•
•
Automated multi-enclosure system with online GC and fast
response VOC analysis
Inexpensive leaf cuvette measurement systems
Eddy Flux Systems
•
•
Relaxed eddy accumulation
Disjunct eddy accumulation and eddy covariance
Tethered Balloon Sampling Systems
•
VOC samplers, integrated ozone, CO2, T, RH
University Users & Technology Transfer Recipients:
Georgia Tech., U. Colorado, Wash. State U., South Dakota
Tech., U. C. Irvine, U. C. Berkeley, Philadelphia University,
U. Wisconsin, U. Wyoming, ETH-Zurich, Edinburgh U.,
Lancaster U., U. Witwatersrand, U. Sao Paulo, U. Aviero
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
5
1996-2001 NCAR/ACD Tropical BVOC Studies
SAFARI
La Selva
(Costa Rica)
EXPRESSO
(S. Africa)
(C. Africa)
LBA
(Amazon)
Xishuangbanna
(China)
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
6
Tropical BVOC Investigators
NCAR/ACD staff: Bill Baugh, Guy Brasseur, Jim Greenberg, Alex
Guenther, Peter Harley, Lee Klinger, Sasha Madronich
NCAR/ACD students and post-docs: Brad Baker, Sue
Durlak, Bai Jianhui, Pierre Prevost, Janne Rinne, Dominique Serca,
Perola Vasconcellos, Lee Vierling
University Collaborators: Paulo Artaxo, Clobite Bouka-Biona,
Deborah Clark, Nick Hewitt, Toni James, Jules Loemba, Hank
Loescher, Yadvinder Mahli, Williams Martins, Luanne Otter, Sue
Owen, Emiliano Pegoraro, Elmar Veenendaal, Oscar Vega
Other Collaborators: Chris Geron, Juergen Kesselmeier,
Luciana Vanni Gatti, Qing Jun
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
7
Why Investigate Tropical Biogenic VOC?
1. Large fraction of
global biogenic VOC
emissions
2. Strong vertical
transport
3. Rapid land use
change
Alex Guenther
Isoprene from other
regions (21%)
Isoprene from
tropics (79%)
Biosphere-Atmosphere Trace Gas Exchange
8
NCAR/ACD Enclosure Measurements
Tropical rainforests
Costa Rica: 50% (weighted average)
W. Amazon: 40%
What fraction of woody
plants emit isoprene?
E. Amazon : 25%
Congo: 20% (weighted average)
South China: 15% (weighted average)
Tropical savannas
African savannas (3 types): 5-15%
(weighted)
African savannas (4 types): 25-50%
(weighted)
Australian savannas (2 types): 55-70%
(weighted average)
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
9
Isoprene Emission Response
Do tropical and temperate plants respond similarly?
3
1.6
TD ( C)
2.5
Isoprene emission activity
Isoprene emission activity
o
25
30
35
2
1.5
1.2
0.8
LAI=0.1
LAI=2
LAI=5
0.4
0
1
30
35
TM (oC)
40
45
500
1000
1500
2000
PPFD (mol m -2 s-1)
Temperature growth envir.
Alex Guenther
0
Light growth environment
Biosphere-Atmosphere Trace Gas Exchange
10
NCAR/ACD Eddy Flux Measurements
Diurnal Variations
Mean Midday Net Flux
Isoprene flux
Sensible Heat Flux
July 8, 2000
Tapajos, Brazil
250
200
Isoprene flux
-2 -1
(mg C m h )
Tropical Isoprene Flux Summary
Costa Rica: 1.5-3 mg C m-2 h-1
E. Amazon: 1-3 mg C m-2 h-1
Congo: 1-2.5 mg C m-2 h-1
Botswana: <0.5 mg C m-2 h-1
S. Africa: <0.5 mg C m-2 h-1
300
Sensible heat flux, W m-2
3
2
150
100
50
1
0
-50
0
-100
4
9
14
19
Hour of Day
Maun, Botswana
a-pinene (mg C m-2 h-1)
3.5
3
2.5
2
1.5
1
0.5
0
9
13
17
Hour of Day
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
11
NCAR/ACD Concentration Measurements
Average midday mixed-layer isoprene
from aircraft and blimp sampling
W. Amazon:
15-34 ppbC (forest)
8 ppbC (pasture/forest)
E. Amazon:
2 ppbC (pasture/forest)
Congo:
5 ppbC (forest)
Central Africa:
2 ppbC (degraded forest)
Oxy-VOC over tropical landscapes
Hexanal, hexenol, hexenal: 0.1- 1.5 ppbC
Acetone, methanol, toluene, formaldehyde,
acetaldehyde: 1 – 10 ppbC
Alex Guenther
Characterizing the combined
influence of regional
emissions, transport and
chemistry
Biosphere-Atmosphere Trace Gas Exchange
12
Modeling BVOC Emission Distributions
at 1 km2 spatial resolution
Foliage density
% broadleaf
tree foliage
% shrub
foliage
Floristic
regions
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
13
Characterizing Tropical Floristic Regions
(regions with genetically related vegetation)
1. NCAR/ACD/BAI studies (14)
3. Studies from similar regions (17)
2. Other tropical studies (4)
4. Default values (8)
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
14
NCAR/ACD Tropical BVOC Publications
EXPRESSO special section of J. Geophysical
Research 104 (1999)
NCAR/ACD authorship on tropical BVOC papers
• 7 published (5 EXPRESSO, 2 LBA)
• 6 submitted (2 EXPRESSO, 1 LBA, 1 China, 1
Costa Rica, 1 SAFARI/KALAHARI)
• 10 in preparation (5 LBA, 4 SAFARI, 1 China)
The authorship of these publications includes
more than 35 university and other collaborators
Alex Guenther
Biosphere-Atmosphere Trace Gas Exchange
15
Future Directions for Biosphere-Atmosphere
Trace Gas Exchange Investigations
ACD
MIRAGE
Initiative
Landcover change:
plantations, crop, urban
Secondary org. aerosols
ACD
Reactive
Carbon Init.
ACD BioChemClimate Init.
NCAR
Biogeosci.
Initiative
NCAR
Wildfire
Initiative
Alex Guenther
Reactive C and N interact.
Terpenoid, oxyVOC, org. N,
O3, NH3, NOy exchange
Aircraft flux measurements
Trace gases (C, N, O3) and
the carbon cycle
Climate variability, stress
(flood, fire, frost)
Biosphere-Atmosphere Trace Gas Exchange
Community
Climate
System
Model
(CCSM)
Weather
Research
and
Forecast
Model
(WRF)
16
Atmospheric Chemistry Division
National Center for Atmospheric Research
ACD Participation in NCAR Initiatives
1) Biogeosciences Initiative
2) Wildfire Initiative
Elisabeth A. Holland
Scientist 3, Global Modeling Group, affiliated with Biosphere,
Atmosphere Interactions Group, ACD, and Land Section in CGD
23-24 October 2001, NSF Review
Beth Holland
NCAR Initiatives
17
Human forcing and chemistry
coupling
Air
pollutants
Chemical
Radiative
Environment balance Physical
O3, NOx, CH4
Environment
RONO2 , OH,
CO2 ,N2O,NOy
Trace gas
temp,
Biogenic VOC
deposition
light
Emission
Human
Activities
Biosphere
Landcover
change
Beth Holland
NCAR Initiatives
18
Chemistry
CO2, CH4, N2O
O3, VOCs, NOx, aerosols
Biogeochemistry
Aerodynamics
Carbon Assimilation
Decomposition
Mineralization
Water
Biogeophysics
Energy
Minutes-To-Hours
Heat
Moisture
Momentum
Microclimate
Canopy Physiology
Days-To-Weeks
Years-To-Centuries
Beth Holland
Climate
Temperature, Precipitation,
Radiation, Humidity, Wind
Evaporation
Transpiration
Snow Melt
Infiltration
Runoff
Hydrologic
Cycle
Phenology
Intercepted
Water
Snow
Soil Water
Hydrology
Bud Break
Leaf Senescence
Species Composition
Ecosystem Structure
Nutrient Availability
Water
Gross Primary Production
Plant Respiration
Microbial Respiration
Nutrient Availability
Watersheds
Ecosystems
Surface Water
Subsurface Water
Geomorphology
Species Composition
Ecosystem Structure
Vegetation
Dynamics
NCAR Initiatives
Disturbance
Fires
Hurricanes
Ice Storms
Windthrows
19
Fit with NSF Geosciences Plan
NSF Geosciences Beyond 2000: Understanding and Predicting Earth’s Environment
and Habitability, section on Planetary Metabolism:
“Understanding how the fluxes of mass and energy among various components of the solid and
fluid Earth link to biological activity on and beneath its surface represents a fundamental
goal of current research. This understanding of planetary metabolism bears directly on key
scientific questions concerning the co-evolution of different components of the Earth system
including life, as well as on the most pressing environmental questions of our time. Present
understanding of these issues is very incomplete; the attack on the problem will require
extensive interdisciplinary collaboration and will rely upon the achievements of all. This
attack will employ a hierarchy of models; it will include interdisciplinary problem analysis and
the synthesis, interpretation, and application of global-scale data sets, including those
obtained by continuous monitoring from space and from new land and ocean-based
observing systems. “
This plan fits with two of the ” five primary challenges facing researchers in the study of planetary
metabolism:
1.determining how the biogeochemical cycles of carbon, nitrogen, oxygen, phosphorus, and
sulfur are coupled;
5.developing sufficiently sophisticated models to explain historic events and predict future
changes in planetary metabolism.”
http://www.geo.nsf.gov/adgeo/geo2000
Beth Holland
NCAR Initiatives
20
WHY NOW?
•
Decade of land model development led by Gordon Bonan has
produced the state of the art model for surface energy, water and
carbon dioxide exchange and a framework which facilitated the
implementation of surface chemical exchanges.
•
Component models of reactive C and N exchanges have been
developed by Alex Guenther and me and are ready for implementation
in the land model. This effort was conducted in parallel with Gordon’s
effort.
•
The growing number of measurements of surface fluxes and
concentrations of reactive carbon and nitrogen are now available for
model evaluation.
•
Fast track development of this model coupling will give us a tool to
articulate and refine key global science questions for the next 5-10
years.
Beth Holland
NCAR Initiatives
21
Wet and Dry Deposition Fluxes for the U.S.
dry deposition flux of particulate NH4+
wet deposition flux of NH4+
dry deposition flux of gaseous HNO3
wet deposition flux of NO3-
dry deposition flux of particulate NO3-
Beth Holland
NCAR Initiatives
22
Wet and Dry Deposition Fluxes for Europe
wet deposition of NH4+
wet deposition flux of NO317.1
8.1
1.9
8.6
4.1
0.9
0.0
0.0
0.0
dry deposition of particulate NO3-
dry deposition of gaseous HNO3
dry deposition of gaseous NO2
Beth Holland
dry deposition of particulate NH4+
11.2
11.1
3.1
5.6
5.5
1.6
0.0
0.0
0.0
NCAR Initiatives
23
Model Comparisons
Beth Holland
NCAR Initiatives
24
Societal Relevance
• The coupling of biosphere feedbacks to the chemical and
climate system was identified as a key gap in our understanding
of current and future changes in atmospheric composition in the
IPCC 2001 report.
• The coupling directly and indirectly impacts concentrations of
key greenhouse gases specified in the Kyoto protocol: CO2 ,
CH4, N2O, and O3,
• This will provide us with the tools for evaluating future climate,
atmospheric composition, and air quality needed for integrated
assessments.
Beth Holland
NCAR Initiatives
25
Partners
ACD:
Alex Guenther, Bill Baugh, Doug Kinnison, J.F. Lamarque, Danny
McKenna, Robbie Staufer, Xuexi Ti, Stacy Walters, Christine
Wiedinmyer
CGD:
Gordon Bonan, Sam Levis, Phil Rasch, Peter Thornton
University Collaborations:
Inez Fung, UC-Berkeley
Bill Parton, Colorado State University
Beth Holland
NCAR Initiatives
26
Science Questions
• How do the bio-atmospheric cycles of carbon and nitrogen
interact to influence the oxidizing capacity of the atmosphere
and climate?
– now?
– over the course of recent decades?
– pre-industrially
– and in the future?
• How is this coupling influenced by key processes?
– urbanization?
– wildfires?
– land cover change?
– human activity?
Beth Holland
NCAR Initiatives
27
Biogeosciences Initiative: Measurements
•
•
Goals of Measurement Component:
– Sensor development
– Deployment on airborne, surface network, balloon platforms
Instrument Development Goals:
– Continue improvements to airborne CO and CO2 trace gas
measurements, initially funded by the NCAR Directors’ Opportunity
Fund, and internal ACD and ATD funds.
– Conversion of an existing O2/N2 shipboard instrument for airborne
operations.
– Development of an improved chemical/meteorological tethersonde,
applying the same technology to improved chemical sensors for
ATD’s surface flux system. These advances may lead eventually to
new capabilities for dropsondes and surface towers.
Collaborative effort involving ACD, ATD, MMM, and RAP
Beth Holland
NCAR Initiatives
28
ACD Wildfire Research
Research Questions
•Are there relationships between the processes
controlling oxygenated VOC emissions from ambient
temperatures and wildfire heat stressed vegetation ?
• Do VOC emissions have a significant role in wildfire
combustion physics ?
• Are the landcover databases developed for biogenic
emission modeling useful for wildfire modeling?
Beth Holland
NCAR Initiatives
29
Atmospheric Chemistry Division
National Center for Atmospheric Research
MOZART and future global
tropospheric modeling in ACD
Danny McKenna
Division Director
24-26 October 2001, NSF Review
Danny McKenna
MOZART and global tropospheric modeling
30
MOZART:
Model for OZone And Related chemical Tracers
MOZART was developed by ACD as a contribution to NSF’s
Global Tropospheric Chemistry Program (GTCP).
MOZART was to develop a community tool capable of:
• Understanding the influence of photochemical and transport
processes on the global distribution of chemical compounds in
the atmosphere.
• Quantifying the
compounds
global
and
regional
budgets
of
these
• Assisting in the interpretation of field measurements and in the
assimilation of space observations
• Predicting the evolution of the atmospheric composition in
response to natural and human-induced perturbations
Danny McKenna
MOZART and global tropospheric modeling
31
MOZART Development and User
Community
ACD
Other Institutions
– Danny McKenna
– Guy Brasseur
(MPI, Hamburg)
– Louisa Emmons
– Denise Mauzerall
(Princeton)
– Doug Kinnison
– Mike Newchurch
(University of Alabama)
– J.F. Lamarque
– Don Wuebbles
(Univ. of Illinois)
– Xuexi Tie
– Derek Cunnold
(Georgia Tech)
– Stacy Walters
– Larry Horowitz
(NOAA GFDL)
– Claire Granier
(NOAA, SACNRS)
– Didier Hauglustaine
(SACNRS, Paris)
– J.-F. Muller
(Belgian Inst. Space Aeronomy)
– Martin Schultz
(MPI Hamburg)
CGD
– Phil Rasch
Web Page… http://acd.ucar.edu/models/MOZART/
Danny McKenna
MOZART and global tropospheric modeling
32
MOZART is a Community Model
- Three Versions • MOZART-1: is a Global Tropospheric Chemical-Transport Model
• Brasseur et al., 103, No. D21, J. Geophys. Res., 28265-28289, 1998.
• MOZART-2: is a revised version of MOZART-1
• Improvements in the surface emissions, chemical mechanism, and
advection.
• Description paper (Horowitz et al., JGR, in preparation, 2001).
• Release by January 1, 2002.
• MOZART-3: extension of MOZART-2. Stratospheric and Mesospheric
chemical and physical processes.
• EOS/Aura pre-launch algorithm development.
• EOS/Aura HIRDLS data assimilation.
• The MOZART-3 framework “test bed” for WACCM chemistry development
• Estimated release Spring/Summer 2002.
Danny McKenna
MOZART and global tropospheric modeling
33
MOZART Structure
Data Assimilation
Analyzed
Met. Fields
e.g.,
MOPITT CO, CH4
HIRDLS Species
e.g., DAO, ECMWF,
NCEP
MOZART
MATCH
Transport + Physics
Versions 1,2,3
Preprocessor Incorporates:
Climate Model
Met. Fields
e.g., MACCM3
Danny McKenna
1) Machine Architecture
2) Chem. Mech./Solution Approach
3) Emissions
4) Wet/Dry Deposition
5) Advection, Diff., Convection
6) Input/output
MOZART and global tropospheric modeling
34
MOZART-2 Description
• Resolution (typical) – 278,528 Grid Cells:
• Surface to approximately 40 km altitude – 1-2 km resolution
• Horizontal Resolution: 2.8° X 2.8 °
• Dynamical Processes:
• Met. Fields: Driven by MACCM3 or Analyzed Fields (e.g., NCEP)- winds and temperatures
• Advection: Flux-form semi-Lagrangian advection scheme of Lin and Rood [1996]
• Convection: Rediagnosed from MATCH using Hack [1994] for mid-level convections and
Zhang and MacFarlane [1995] scheme for deep convection
• Boundary layer exchange: Parameterization of Holstag and Boville [1993]
• Wet and Dry Deposition:
• Wet deposition:
- Represented as a first-order loss process within the chemistry operator, using large
scale and convective precipitation rates diagnosted by MATCH.
- Highly soluble species are removed by in-cloud scavenging and below cloud washout
(Brasseur et al., 1998)
- Mildly soluble species removed by in-cloud scavenging (Giorgi and Chamedes, 1985)
• Dry surface deposition: uses the approach of Wesely [1989]
Danny McKenna
MOZART and global tropospheric modeling
35
MOZART-2 Description Continued
• Chemical Constituents and Mechanism:
• Approximate 65 Chemical Species:
• Contained in Ox, NOx, HOx; plus CH4, C2H6, C3H8, C2H4, C3H6, C4H10, isoprene, terpenes
• 133 gas-phase, 2 heterogeneous, and 33 photolytic reactions
• Source Gas Emissions:
• Surface Emission: CO, NOx, CH4, CH3OH, C2H6, C3H8, C2H4, C3H6, C4H10, C5H8, C10H16, CH3COCH3
• NOx Lightning Emission:  5 Tg N yr-1 [Pickering et al, 1998]
• Aircraft Emissions: CO, CH4, NOx (0.44 Tg N yr-1) [NASA, 1995]
• Stratospheric Constituents Constrained for:
• NOx, HNO3, N2O5, CH4, CO, and N2O (middle atmosphere model STARS, Brasseur et al., 1997),
• O3 below 100 hPa (Logan, 1999) to the thermal tropopause; above 100 hPa (HALOE data,
Randel et al., 1999),
• 10-day relaxation time constant is used for all species.
• Computational Costs (using the current Blackforest configuration)
• 1 model year  1.0 wall clock day (5 models years per wall clock day soon!)
Danny McKenna
MOZART and global tropospheric modeling
36
Examples of Problems Addressed
with MOZART
• Comparison of simulations of key
tropospheric constituents with
observations:
- Ozonesonde data, ground-based CO,
Aircraft NOx etc…
• Analysis of field observations and other
measurement programs:
-TOPSE O3,
• Analysis and assimilation of space
observations:
- MOPITT (CO) and GOME (NO2)
• Impact of aerosols on concentration of
gas-phase compounds
- IPCC Intercomparison
- Sensitivity study with TOPSE NOx data
Danny McKenna
• Long-range transport of emissions from
Asia and other industrial regions.
- Tagged CO source regions.
- Mauzerall et al., , J. Geophys. Res., 105, 17,89517,910, 2000.
• Role of lightning and biomass burning
on ozone.
- Hauglustaine et al., Geophys. Res. Lett., 26,
3305-3308, 1999.
- Hauglustaine et al., J. Atmos. Chem., 38, 277294, 2001.
- Tie et al., J. Geophys. Res., 106 (D3), 3167,
2001.
• Impact of tropospheric O3 on
agricultural yields in China
- Mauzerall et al., 2002.
MOZART and global tropospheric modeling
37
MOZART-2 Accomplishments
Comparison of O3 with Ozonesondes (Logan, 1999)
Altitude, hPa
Horowitz et al.,
JGR, in prep., 2001.
Ozone (PPBV)
Danny McKenna
MOZART and global tropospheric modeling
38
MOZART-2 Accomplishments
Comparison to surface CO CMDL Data
Horowitz et al., JGR,
in prep., 2001.
Month
Danny McKenna
MOZART and global tropospheric modeling
39
MOZART-2 Accomplishments
Comparison to Aircraft NOx Observations
Horowitz et al., JGR,
in prep., 2001.
NOx (pptv)
Danny McKenna
MOZART and global tropospheric modeling
40
MOZART-2 Accomplishments
TOPSE Campaign, Ozone Change
Emmons et al., JGR,
in prep., 2001.
Danny McKenna
MOZART and global tropospheric modeling
41
MOZART-1 Accomplishments
Black Carbon Intercomparison, IPCC 2001
• Sulfate aerosols
Sulfur surface emissions
Gas-phase sulfuric acid
Aqueous phase chemistry
Wet and dry depositions
Transport
• Blackcarbon aerosols
Surface emission
Hydrophobic and hydrophilic
conversion
Wet and dry depositions
Transport
Model (ng C m-3)
Several types of aerosols are
currently calculated in
MOZART, including
• Ammonium Nitrate
Chemical transformation
Transport
IPCC Climate Change 2001, Chapter 5, Figure 5.10.
Danny McKenna
Observations (ng C m-3)
MOZART and global tropospheric modeling
42
MOZART-2 Accomplishments
CO tagging
Danny McKenna
MOZART and global tropospheric modeling
43
Earth System Transport Model
• Continued support for MOZART
• Progressive migration to a new Earth System Transport Model
(ESTM),
- MOZART Chemistry / Solver
- MATCH transport & physics
- CSM Land/ocean models coupled to emission modules
• CCM-Chemistry as above, but…
- CSM dynamics & transport
Common Framework for Offline CTM and on-line GCM
Danny McKenna
MOZART and global tropospheric modeling
44
On-Line Chemistry Mode
CCSM
Land Use
Model
Emission
Model
MOZART
Chemistry
Atmospheric
Model (CCM3)
Ocean
Model
Danny McKenna
Deposition
Model
MOZART and global tropospheric modeling
45
Chemistry Transport Mode with
Interactive Land
CCSM-Framework
Land Use
Model
Emission
Model
MOZART
Chemistry
MATCH
Transport
Deposition
Model
Analyzed
Met. Fields, Ocean Data
e.g., DAO, ECMWF, NCEP
Danny McKenna
MOZART and global tropospheric modeling
46
Potential Chemistry / Climate Studies
• O3 Budget of the Troposphere
- Trends in relative contributions from stratosphere and human induced change.
- Temporal changes in the stratosphere flux of O3
- What influences ozone more: climate change or emission change?
• Influence of oxidants on aerosol formation
- Changes in the availability of SO2, O3, H2O2, HNO3, & NH3
- Feedback to cloud scale and large scale dynamics
• Influence of Climate on Greenhouse and other gas emissions.
- Land use and climate change influence CH4 and N2O production.
- Feedback onto primary production and emission.
• Influence of O3 loss on composition, climate, and transport
- Can O3 loss stabilize the Arctic Vortex?
- Can trends in CH4 and N2O be simulated?
- Can O3 loss influence tropospheric temperature trends?
Danny McKenna
MOZART and global tropospheric modeling
47