Coupling the Chemistry in Earth System Models on multiple Scales (ChESS)

Transcription

1 Coupling the Chemistry in Earth System Models on multiple Scales (ChESS) Patrick Jöckel

2 Outline Earth System Science a computational science Atmospheric Chemistry The Earth System Model EMAC DEISA/DECI Project ChESS: The lower boundary: coupling the ocean Towards smaller scales: nesting a regional model

3 Earth System Science a computational science

4 Figure of the heavenly bodies An illustration of the Ptolemaic geocentric system by the cosmographer and cartographer Bartolomeu Velho, 1568 (Bibliothèque Nationale, Paris)

5 Earth System Model = the Earth in a computer an artificial system (laboratory system) with the same characteristics as the terrestrial climate system description of all relevant processes in sufficient detail

6 atmospheric and oceanic (thermohaline) circulation File:Earth_Global _Circulation.jpg Thermohaline_Zirkulation

7 Sun thermal radiation radiation Earth orbit atmosphere hydrosphere cryosphere biosphere Pedopedosphäre sphere air ocean rivers lakes groundwater glaciers sea-ice snow vegetation soil litosphere anthrosphere rock sociovolcanos economy continents technology crust coupling : circulation of energy, momentum, constituents change of state variables by physical, chemical, biological, socio-economic processes

8 Mathematical formulation (e.g., atmospheric dynamics) Conservation of momentum Newton's 2. Law DV 1 2 V = g c p af Dt Conservation of mass Continuity equation: D V =0 Dt Conservation of energy 1. Law of thermodynamics: 1 c V T = Q Equation of state (air ~ ideal gas): p= Rg T Mm

9 Mathematical formulation (e.g., atmospheric dynamics) Conservation of momentum - Newton's 2. Law DV 1 2 V = g c p af Dt Conservation coupled of mass Continuity PDE system equation: non-linear D Vsystem =0 open (δq) Dt rotating frame of reference Conservation numerous of energy - 1. Law of processes onthermodynamics: a wide range of spatio-temporal scales 1 c V T = Q Equation of state (air ~ ideal gas): p= Rg T Mm

10 The characteristic time and space scales of the spectrum of Earth processes 1994) , Patrick Jöckel, DEISA PRACE(Barron, Symposium 2010, Barcelona

11 1950 (Charney, Fjørtoft, von Neumann): first numerical weather forecast on ENIAC (Electronic Numerical Integrator and Computer) forecast time: 24 hours computation: 24 hours

12 1950 (Charney, Fjørtoft, von Neumann): first numerical weather forecast on ENIAC (Electronic Numerical Integrator and Computer) forecast time: 24 hours computation: 24 hours 2008 (Lynch & Lynch): reconstruction on mobile-phone (JAVA-application): forecast time: 24 hours computation: < 1 second (!!!) Lynch & Lynch, Weather 63, ,

13 processing power 1 P Flops/s T Flops/s fastest computer(s) in the world 1 G Flops/s 1 M Flops/s mass product 1. numerical weather forecast

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15 Challenges wide range of spatio-temporal scales combination of various algorithms in operator splitting all with special requirements, e.g. w.r.t. parallelisation load imbalancing issues in most cases historically grown ( legacy ) codes several decades of development very large codes (~ lines of code) porting / adaption to new hard-/software is an issue large output ~ TByte / simulated year (T42L90MA with complex chemistry)

16 Atmospheric Chemistry

17 The role of atmospheric chemistry absorption / emission of radiation differential heating/cooling forcing for dynamics urban photochemical smog greenhouse gases acid rain atmospheric chemistry stratospheric ozone depletion self cleansing of the atmosphere constituent cycles many interactions highly non-linear wide range of spatial and temporal scales

18 Atmospheric Chemistry: many processes gas phase anthropogenic emissions clouds aerosol Transformation Emission Deposition Transport natural emissions dry deposition wet deposition advection convection diffusion scavenging sedimentation OCEAN AND BIOSPHERE

19 Spatial and temporal scales of variability for atmospheric constituents. cf. Figure 1.17, page 41, Atmospheric Chemistry and Physics, J.H. Seinfeld & S.N. Pandis, 1997.

20 1 N2O + O( D) 36% 64% N2 + O2 very fast auto-catalytic cycles + hν O2 hν slow M+O2 O fast hν slow -O NO2+O2 O3 + NO +O - O2 hν OH+NO2 HO2+NO2 + OH 1 H2O + O( D) M HO2+O2 +O3 -O2 HNO3 HO2NO2 hν

21 radical family photolysis long range transport source gases reservoir species radical family washout & deposition photolysis mathematically described by a (stiff) system of coupled ODEs

22 Number* of sub-time steps of the ODE solver for the kinetic system T106L90MA ~ x x 90 (~80 km) ; Δt = 6 min 16-FEB :00 UTC *vertical average

23 Number of sub-time steps of the ODE solver for the kinetic system T106L90MA ~ x x 90 (~80 km) ; Δt = 6 min ~ 80 km 16-FEB :00 UTC ; 90 E surface

24 The Earth System Model EMAC

25 EMAC: ECHAM/MESSy Atmospheric Chemistry European Center HAmburg Model / Modular Earth Submodel System a General Circulation Model (GCM) of the atmosphere version 5 (Roeckner et. al., 2006) needs to be explained a bit further version 1 (Jöckel et al., 2005) MPI for Meteorology MPI for Chemistry DLR Institute for Atmospheric Physics University of Mainz Karlsruhe Institute of Technology Free University of Berlin Cyprus Institute... EMAC evaluated (Jöckel et. al, 2006)

26 different domains - atmosphere - hydrosphere - cryosphere - biosphere - pedosphere - litosphere - anthrosphere M O D U L A R I S A T I O N I N T E G R A T I O N simple and efficient interface structure process oriented approach! Comprehensive Earth System Model one code / flexible complexity transparent (user friendly) highly consistent single components easily exchangeable continuous further development always state of the art and applicable for scientific purposes

27 different domains - atmosphere - hydrosphere - cryosphere - biosphere - pedosphere - litosphere - anthrosphere M O D U L A R I S A T I O N I N T E G R A T I O N simple and efficient interface structure process oriented approach! Comprehensive Earth System Model one code / flexible complexity transparent (user friendly) highly consistent single components easily exchangeable continuous further development always state of the art and applicable for scientific purposes Standardisation

28 Base Model Layer: power supply Base Model Interface Layer: multiple socket outlet Submodel Interface Layer: connector Submodel Core Layer: the machinery...

29 MESSy is (a project providing)... an interface with infrastructure to couple 'processes' (=submodels) to a GCM (= base model) a set of processes coded as switchable submodels a (simple) coding standard... Ocean Atmosphere chemistry advection biology MESSy radiation dynamics clock/run control chemistry (base model)... microphysics standard interface land use vegetation Land surface soil convection... (Jöckel et al., ACP, 2005)

30 plug&play uncertainty w.r.t. process formulation ECHAM5 MESSy BMIL MESSy SMIL T1 / T2 / T3 EC / EC2 B1 / B2 ZH / ZHW 4 different convection schemes

31 average precipitation [mm/day] GPCP (=obs.) Tiedtke Nordeng ECMWF Zhang /McFarlane / Hack Bechtold (H. Tost, 2006)

32 Granularity (Example): Atmospheric Chemistry JVAL gas phase MECCA _AERO anthropogenic emissions Emission clouds aerosol PSC CLOUD SCAV DRYDEP Transformation dry deposition TRACER Deposition Transport natural emissions wet deposition advection convection diffusion ONLEM LNOX CONVECT sediofflem AIRSEA SEDI mentation CVTRANS TNUDGE OCEAN AND BIOSPHERE scavenging SCAV

33 consistent simulation of (dynamical and chemical) state of the atmosphere between surface and 0.01 hpa 4 year average ( , excl. 2002) of ozone (DJF) [μmol/mol] (Jöckel et al., ACP, 2006)

34 SH vortex split 2002 reproduced Total Ozone [DU] 26 Sep 2002 EMAC (S2) TOMS (Jöckel et al., ACP, 2006)

35 Example: tropospheric CO NOAA/ESRL EMAC (Jöckel et al., ACP, 2006)

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37 DEISA/DECI Project ChESS: Part I: The lower boundary coupling the ocean

38 Atmospheric Chemistry: Input from the ocean gas phase anthropogenic emissions Emission clouds aerosol Transformation dry deposition TRACER Deposition Transport natural emissions wet deposition advection convection diffusion scavenging sedimentation OCEAN AND BIOSPHERE

39 alternative process descriptions: increasing consistency ECHAM5 MESSy OFFLEM emission flux consistent with prescribed oceanic emissions wind speed salinity ocean circulation

40 alternative process descriptions: increasing consistency emission flux consistent with ECHAM5 ECHAM5 MESSy MESSy OFFLEM OFFLEM AIRSEA prescribed oceanic emissions prescribed oceanic concentrations explicit calculation of air sea exchange wind speed salinity ocean circulation - + -/+

41 Vertical profiles of methanol (CH3OH) (Pozzer et al., ACP, 2007)

42 ECHAM5 ECHAM5 MESSy MPIOM MESSy OFFLEM OFFLEM AIRSEA HAMOCC prescribed oceanic emissions prescribed oceanic concentrations explicit calculation of air sea exchange explicit calculation of oceanic concentrations emission flux consistent with wind speed salinity ocean circulation - + -/

43 Chemistry in the Atmosphere Ocean System (Andrea Pozzer, Bastian Kern, Patrick Jöckel) MECCA/SCAV/ONLEM/ OFFLEM/DRYDEP/... ECHAM5 ATMOSPHERIC PHYSICS ATMOSPHERIC CHEMISTRY MESSy OCEAN PHYSICS MPIOM OCEAN CHEMISTRY HAMMOC

44 Processor ID # for 4 x 4 decomposition Atmosphere Ocean rotated grid (poles over land) Challenges: different grid-structures and parallel decompositions - requires mass-conserving transformations - communication overhead (MPI)

45 sea level [m] Water balance... year (const. pre-industrial climate forcing) (A. Pozzer)

46 Δ-Temperature [K] compared to Temperature Trend EMMAC (A. Pozzer)

47 simulated (5-year average) ocean surface (6 m) chlorophyll content mg/m3 (B. Kern)

48 simulated (5-year average) ocean surface (6 m) chlorophyll content dependency on nutrient influx by rivers (with without) mg/m3 (B. Kern)

49 pr el im in ar y!!! coupling to the atmosphere...

50 DEISA/DECI Project ChESS: Part II: Towards smaller scales nesting a regional model

51 Modeling of AtmospheriC CHemIstry And Transport from the global to the local scales (Astrid Kerkweg, Patrick Jöckel) 1. COSMO COSMO/MESSy 2. on-line (one-way) nesting of COSMO/MESSy into ECHAM5/MESSy field camapigns global regional local scale consistent dynamical AND chemical BC (with high frequency)

52 consistent boundary conditions ECHAM5/MESSy COSMO(7 km)/messy COSMO(2 km)/messy Tasks: implementation of MESSy infrastructure (+ submodels) into COSMO implementation of INT2COSMO as MESSy-submodel for on-line grid transformation implementation of the MESSy multi-model driver (MMD), based on MPI standard

53 ECHAM5 Multiple instances possible due to client server architecture of MMD... COSMO 1 COSMO 2 COSMO 2-1 COSMO 3 COSMO 3-1 COSMO COSMO 2-1-2

54 temperature at 500 hpa

55 Summary Earth System Science is a computational science... facing specific challenges as compared to other communities Consideration of chemical processes (in atmosphere, ocean,...) is essential for understanding constituent cycles (but introduces new challenges) DEISA provided/provides an ideal extreme computing environment required for further progress dynamical and chemical coupling of the atmosphere-ocean system nesting of small -scale model for bridging the scales first results are very promising and provide a proof-of-concept for the (modular) approach of the Modular Earth Submodel System (MESSy) Thanks to staff of RZG, SARA, LRZ (DEISA!), DKRZ for their support!