atmosphere modelling group · 2010-12-07 · ¾increase the methane by 10 in the atmosphere would...
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Atmosphere Modelling GroupAtmosphere Modelling Group(with a strong focus on new particle formation)(with a strong focus on new particle formation)
University of HelsinkiUniversity of HelsinkiDepartment of PhysicsDepartment of Physics
Division of Atmospheric SciencesDivision of Atmospheric Sciences
MALTE SOSA
SCADIS
seconds days months years
cm
m
eter
ski
lom
eter
s
ECHAM5-HAM
UHMA
PENCIL-COUD
MALTE SOSA
SCADIS
seconds days months years
cm
m
eter
ski
lom
eter
s
ECHAM5-HAM
UHMA
Luxi Zhou
Ditte Mogensen
Risto Makkonen
HenriVuollekoski
Rosa Gierens
Johanna Lauros
K.V. Gopalkrishnan
Sampo Smolander
Anton Rusanen
Sanna-LiisaSihto
He QingyangChatriya Watcharapaskorn
PENCILCLOUD
Natalia Babkovskaia
Michael Boy(group leader)
The UHMA box model
coagulation
cloud dropletactivation
nucleation
condensation
Figure: Miikka Dal Maso
UHMAUHMA –– University of Helsinki MultiUniversity of Helsinki Multi--component Aerosol modelcomponent Aerosol model
MECCO – a method to estimateconcentrations ofcondensing organics
Vuollekoski, H., et al. Journal of Aerosol Science,41, 1080-1089, 2010.
What is growing the particles?
0 probability 1
Basic idea of Markov chain Monte Carlo methods
MECCO – a method toestimate concentrationsof condensing organics
UHMA
Testing MECCO--UHMA: create perfect data
UHMA
MECCO—UHMAis working
Field data needs to be smoothened
Preliminary testing of with field data
MALTE / SOSA / SCADISMALTE / SOSA / SCADIS
0 m
15 m
3000 m
METEOROLOGY
EMISSIONSCHEMISTRY
KPP
MCM
MEGAN
SCADIS
Aerosol
UHMA
MALTEMALTE –– Model to predict new AerosolModel to predict new Aerosolformation in the Lowerformation in the Lower TropospherTropospher
Particle concentration and fluxdynamics in the atmospheric boundarylayer as the indicator of formationmechanism
Lauros et al., Atmos. Chem. Phys. Discuss. 10, 20005-20033, 2010
Measurements: DMPS
J = K * [H2SO4]2 (K = 5*10-13 cm3 s-1)
J = Korg1 * * [H2SO4] * {[Mont.][O3]}
J = Korg2 * * [H2SO4] * {[Mont.] [OH]}
MALTE (HyytiMALTE (Hyytiäällää, March 2006), March 2006)
Vertical profile of particles withVertical profile of particles withDDpp > 10 nm> 10 nm
Observation
Organic inducednucleation
Kinetic nucleation (H2SO4)
SOSASOSA –– Model to calculate theModel to calculate theconcentrations of Organicconcentrations of Organic vapoursvapours andand
SulphuricSulphuric AcidAcid
Long term statistical comparison ofdifferent compounds
dark green: days > 75 % of the yearly mean value between 9 am and 3 pmgreen: days > 60 & < 75 % of the yearly mean value between 9 am and 3 pmlight green: days > 50 & < 60 % of the yearly mean value between 9 am and 3 pm
Long-term data analyses: 2003-2008
CSSOHRp 421
Modelling Atmospheric OHModelling Atmospheric OH--Reactivity in a Boreal ForestReactivity in a Boreal Forest
OH-reactivity = loss rate of OH
ROH = kOH+X [X]
Unit of OH-reactivity, ROH is [s-1]
kOH+X is the rate coefficient [cm3mol-1s-1]
[X] is the concentration of chemical compound X
Measured and Modeled OH-reactivity for August 2008
Modeled (blue) and 30 minute resolution, measured OH-reactivity
(black) from the 13th to the 27th of August, 2008 at 14 meters.
Modeled, Measured, and Missing OH-Reactivity
We seem to be able to predict 30-50% of the OH-reactivity!
13-27Aug 13-18Aug 19-27Aug
Modeled 2.5 s-1 2.3 s-1 2.6 s-1
Measured 6.5 s-1 8.6 s-1 5.1 s-1
Missing 4s-1 / 61% 6.2 s-1 / 73% 2.5 s-1 / 49%
peak near ground during nightnight deposition and suppression of boundary layer
Vertical profile of OH-reactivity [s-1]
Seasonally variation for 2008
Contributions from inorganic compounds, isoprene,methane, monoterpenes, and other VOCs.
Fighting fire with fire:
Could NOx emission be used toremove methane in a catastrophicclathrate release scenario?
Clathrate gun hypothesis
Clathratedestablize
Methanerelease
Temperature rise
[Kennet et al. 2000]
Methane clathrate is crystallinesolid which looks like ice, and inwhich a large amount of methaneis trapped within a crystalstructure of water
Clathrates naturally occur inpermafrost and seabed.
Total reservoirs on earth rangesfrom 103 to 104 GtC.
• Greater than 80% of East Siberian Arctic Shelf(ESAS) bottom waters and greater than 50% of surfacewaters are supersaturated with methane regarding to theatmosphere.
• The amount of methane currently coming out ofESAS is comparable to the amount coming out of theentire world's oceans.
•[Shakhova et al., Science 5 March 2010]
Large methane emission at ESAS
7.12.2010 29Osasto / Henkilön nimi / Esityksen nimi
RCP database: By 2100, total methane emission mayincrease 300%.
How is methane oxidized in atmosphere?
15.09.2010 30
CH4 CH3O2OHO2
CH3OOH
HO2
HCHO
NOCH3O
CO CO2hv
Deposition
O2
OH OH
OHOH
hv
CH4 + OH + O2 CH3O2 + H2OCH3 O2 + NO NO2 + CH3OCH3O + O2 HCHO + HO2
HO2 + NO NO2 + OH
CH4+2O2+2NO HCHO+H2O+2NO2
2(NO2 + hv NO + O)2(O + O2 +M O3 +M)
Net: CH4+4O2+2hv HCHO+2O3+H2O
Adding NOx decrease methane.....
R. P. Wayne, Chemistry of Atmosphere, 3rd edition,Oxford University Press, New York, 2000
Adding NOx has both cooling andwarming effects
RF inCH4
A set of models were used to assess the effects of adding NOx
Radiative forcing (RF) is thechange in net irradiance at thetropopause/top of atmosphere.
Baseline scenario:• Unperturbed methane and NOx concentration level.
10M/100M, 1N scenario:• 10/100 times present day methane concentration level ;• Unperturbed NOx concentration level.
10M, 2N scenario:• 10 times present day methane concentration level;• 2 times present day NOx concentration level.
CH4 and NOx concentration were fixedat different values
Increase the methane by 10 in the atmosphere would result in a radiativeforcing change of 2.514 W/m2.
Scenario O3 radiativeforcing (W/m2)
CDNC-albedo relatedradiative forcing (W/m2) CH4 lifetime (years)
1M,1N 0.0 0.0 12
10M, 1N 0.76 2.06 22.2
10M, 2N 1.10 1.70 19.8-0.36+0.34
After double NOx emission …
methane life time change is small
RF change due to ozone and aerosol indirect effect are comparable
EFFECT Magnitude (J/m2)
CH4 removal - 5.95×106
O3 increase + 10.72×106
CDNCincrease
- 11.35×106
Net - 6.58×106
Scenario with CH4 concentrationincreased 10-fold
Doubling of the NOX concentrationfor a year
We do get a net cooling effect!!! But....
How big are the heating and cooling effects?
Cooling effect insignificant
Net cooling effect: -6.58 J/m2 -0.21 W/m2*year
It is too small compared to the initial warming due to methane increase( 2.51 W/m2) as well as associated ozone warming (0.76 W/m2) and aerosolindirect effects (2.06W/m2).
0.21 W/m2 << (2.51 + 0.76 + 2.06) W/m2
Not an effctive way to save us!
Elevated methane level leads to strong CDNC reduction
CDNC reduction leads to positive aerosol indirect effects
CDNC reduction leads to positive aerosol indirect effects
PENCILPENCIL--CloudCloud
Pencil code as a powerful tool forcalculation of the turbulence coupledwith an aerosol dynamic module tostudy cloud processes
Scientific objectivesScientific objectives
• studying the influence of turbulence on theaerosol dynamics and vice versa inside acloud
• investigating the activation of particles atthe cloud boundary
• quantifying the effect of particle productionat the outflow of a cloud
2D aerosol + fluid dynamics model2D aerosol + fluid dynamics model
SCADISSCADIS((SCASCALARLAR DISDISTRIBUTION)TRIBUTION)
SCADIS is a high-resolution 3D model capable ofcomputing the physical processes with bothplant canopy and atmospheric boundary layersimultaneously
Horizontal and Vertical Resolution – As perspecific requirement
TKE OVER HYYTIÄLÄ FOR ONE DAY
ECHAM5ECHAM5--HamHaman aerosolan aerosol--climate modelling systemclimate modelling system
Past, present and futurenew particle formation
Past Present Future
Condensation nuclei(diam
eter > 3 nm)
Cloud condensation nuclei
(diameter > 70 nm
)
#/cm3
Aerosol indirect effect (W/m2
(anthropogenic effect: present-day/future compared topre-industrial)
Aerosol indirect effect (W/m2)(anthropogenic effect: present-day/future compared to
pre-industrial)