Download Mk3.5 simulations

Coupled climate modelling at CSIRO
Presented by
Tony Hirst
CAWCR
Coupled climate models
Four main components: the atmosphere, the land surface and biosphere, the ocean,
and polar ice
Data are computed in short (~15-minute) time-steps over a global grid for a period of
months, years or centuries
Models simulate daily weather and average climate patterns
CSIRO climate model grids
Facilitated by improved computing power and optimised programming
Mk3 grid
Mk2 grid
CSIRO Mk3 climate model
Temperature (oC)
Australian global climate models
BMRC global coupled climate modelling
 BCM – contributed to IPCC TAR (2000)
 also seasonal prediction focus - POAMA
CSIRO global coupled climate modelling
 Mk2 – contributed to IPCC TAR (2000)
 Mk3.0 – contributed to IPCC AR4/CMIP3 (2004)
 Mk3.5 – contributed to CMIP3 (2006)
 Mk3.6 – Control simulation under way
Australian Community Climate and Earth System Simulator
(ACCESS)
– Under development
CSIRO Mk3 global coupled climate model
Atmosphere: Grid T63 (1.9 x 1.9); 18 levels - hybrid ,p
Rotstayn prognostic cloud scheme
Ocean: MOM 2.2 code; Grid 0.95NS x 1.9EW;
31 levels (8 in top 100 m)
Griffies (1998) skew-diffusion form of eddy-induced transport
Sea Ice: Flato-Hibler cavitating-fluid rheology
Semtner Thermodynamics (3 layer)
Land surface: Soil model – 6 levels, 9 soil types
13 vegetation types
Snow cover model – 3 layer
Reference: Gordon et al., 2002
www.dar.csiro.au/publications/gordon_2002a.pdf
CSIRO Mk3.0 and Mk3.5
CSIRO Mk3.0 model limitations
• Cool bias in the climate and ongoing cooling trend
• Poor Southern Ocean Circulation and stratification
• Problems in tropical Pacific climate (mean state, ENSO)
Mk3.5 – Improved physics over Mk3.0
• Improved scheme for oceanic eddy-induced transport
• Improved scheme for wind-forced mixing in the oceanic mixed layer
• Upgraded sea ice numerics
• Ocean surface current speed included in wind stress calculation
• Improved river routing
• Model carefully rebalanced
Control simulations – global mean surface air temperature change
(5yr mean)
Mk3.5 control simulation
Sea ice extent – Southern Hemisphere
(106 km2)
Mk3.0
0
100
200
300
400
500
Mk3.5
0
100
200
300
400
500
SST
Model – obs.
Mk3.0
years 101-200
Mk3.5
years 101-200
SST
Model – obs.
Mk3.0
years 401-500
Mk3.5
years 401-500
Tropical SST (difference Model – Observed)
Annual Mean
Mk3.0
Years 201 – 210
Mk3.5
Years 201 – 210
°
C
Spatial pattern of ENSO SST anomalies (C)
SST anomalies regressed onto
1 stdev NINO 3.4 index
Mk3.0 control
Mk3.5 control (years 301-400)
Power spectrum of NINO 3.4 Index
Mk3.5 control years 201-300
Mk3.0 control
6.4 yr
4.9 yr
5.5 yr
3.5 yr
2.1 yr
Observed
5.1 yr
3.5 yr
3.8 yr
Power spectrum NINO 3.4
6.4 yr
4.9 yr
3.8 yr
Mk3.5 control
years 201-300
5.2 yr
Mk3.5 control
years 301-400
Correlation Between Rainfall and NINO 3.4 – Observed
Correlation Between Rainfall and NINO3.4 – Mk3.0 model
Correlation Between Rainfall and NINO3.4 – Mk3.5 model (years 301-400)
MJO variability
Power spectrum for u200
(eastward propagating)
45 days period
Mixed layer depth – September
(depth in metres)
Observationbased data set
Mk3.0
Years 201 – 210
Mk3.5
Years 201 – 210
Mk3.5 simulations
• Control simulation (Completed at 1300 years length)
• Climate change simulations (following CMIP3/IPCC AR4 protocol)
 CMIP simulation – 1% p.a. CO2 concentration increase for 80 years
 Three 20th century simulations
 SRES A2, A1B, B1, “COMMIT”
• Climate change forcings applied (basic set for CMIP3 protocol)
 Greenhouse Gas concentrations (as equivalent CO2)
 Ozone concentrations (as a 3-D time dependent field)
 Sulphate aerosol (direct effect only)
IPCC SRES scenarios for AR4 simulations
Atmospheric CO2 concentration
Historical
“COMMIT”
Mk3.5 simulations
Global average surface air temperature
Mk3.5 simulations – Output data
•
Output data summary
 Atmospheric fields: monthly, 6 hourly
 Oceanic fields: monthly
 Most data now in standard IPCC AR4 format
 Key contact – Mark Collier ([email protected])
• Availability
1. PCMDI (Mk3.0, Mk3.5 available now) http://www-pcmdi.llnl.gov/
2. OPeNDAP from CSIRO server
Recap on Mk3.5
• Mk3.5 developed and displays significant improvement in several key
attributes
• Drift largely eliminated
• Southern Ocean circulation and stratification improved
• Character of ENSO variability modestly improved
• Set of climate change simulations (IPCC AR4 protocol) is nearly
complete with extensive saving of monthly and 6 hourly data
• Project aims to support usage of model output in other stakeholder
projects
CSIRO Mk3.6
Mk3.6 – Improvements over Mk3.5
 Physics
• Comprehensive prognostic aerosol scheme
• Upgraded radiation code
• Upgraded boundary layer formulation
 Solution
• Significant improvements in simulation of Australian climate
including variability
Simulations: 1. Present-day control performed – 70 years
2. Pre-industrial control under way
– currently at 400 years
Mk3.6 – first mode of rainfall variability
Observed
Modelled – Mk3.6 vs CMIP3 models
CSIRO Mk3.6
ENSO Impact on Australian aerosols – Mk3.6
Correlation aerosol concentration and NINO3.4 SST anomaly
Mineral dust
Sulfate
Carbonaceous
Mk3.6
Future simulations with CSIRO Mk3.6
Mk3.6 – Future simulations
 Simulations to be performed as part of partnership with QCCCE
•
•
•
•
•
•
Pre-industrial control following CMIP5 specification
Historical (~20th century) simulation following CMIP5 specification
All four RCP experiments to 2100
20th century simulations with individual agents
Ensemble simulations
To be performed on new QCCCE machine – computational resources should
be adequate.
 Set of simulations may readily be extended to include the remaining
core CMIP5 (IPCC AR5) experiments
Australian Community Climate and Earth System Simulator
(ACCESS)
Joint initiative of the Bureau of Meteorology and CSIRO,
with university sector involvement to:
 Develop a national approach to model development for
climate and weather prediction
 Focus on the needs of a wide range of stakeholders
ACCESS - Aims
Produce a modelling system capable of supporting:




NWP – Bureau operations
Seasonal prediction – Bureau operations
Provision of model-derived climate information
Climate and climate change simulation
 Contributes to IPCC Assessment Reports
 Includes full carbon cycle
 Includes scales appropriate to support decision making
 Spatial scales (regional)
 Temporal scales (decades – centuries)
Morton and Love (2005) (paraphrased)
ACCESS
Modelling System
M
e
t
OPS
VAR
Dynamic
Vegetation
Atmosphere
Assimilation
O
f
f
i
c
e
What we are aiming
to develop as the
ACCESS Earth
System Model
Atmospheric
Chemistry
Land Surface
Coupler
Sea Ice
Ocean
Carbon cycle
Ocean
BODAS
Dynamic Ocean
Primary Prod.
OBS
ACCESS – First version of global coupled model
Atmosphere
UM 7.3
Land Surface
CABLE
Coupler
OASIS 3.2.5
Sea Ice
CICE 4.0
Ocean
GFDL MOM4p1
ACCESS
Current Computing Infrastructure
 The main computing facility for Mk3 and ACCESS development
has been the HPCCC (located at the Bureau), using two NEC
SX-6 machines.
 The main computing facility for ACCESS development is now the
NCI NF (located at the ANU, Canberra), using two SGI machines
(total cores 3200).
 NCI machine upgrade (to 12,000 core Sun Constellation) is due
in December 2009.
ACCESS
Key Timeline required for AR5
Climate Change simulation
2008/2009
Complete technical coupling
2009/2010
Test and tune coupled system
2010 2nd half Perform and submit CMIP5/AR5 simulations
 Initial aim is to perform minimum set of simulations
for CMIP5/IPCC AR5
CMIP5 and IPCC AR5
Coupled Model Intercomparison Project 5 (CMIP5)
•
International project featuring clearly defined model experimental design including
prescribed emissions and concentrations scenarios and model output data
protocols.
•
IPCC AR5 will use the model results submitted to “CMIP5”
•
Will continue past the AR5
•
Experimental design now set (Taylor et al. ,2009) following extensive reviews.
•
Three experimental suites (a particular model may enter any or all)
 “long-term” simulations
 “near-term” (decadal) hindcast/prediction simulations
 “atmosphere-only” (prescribed SST) simulations – for especially
computationally demanding models
•
Experiments are designated as “Core”, “Tier 1”, “Tier 2”
Long-term
experiments
Long-term experiments
The principal long-term experiments are:
• 500+ year control coupled model - preindustrial
• Historical (1850 – 2005) (ensemble optional)
• Representative concentration pathways (RCPs) 2005 – 2100
 RCP8.5 (Core)
 RCP6 (Tier 1)
 RCP4.5 (Core)
 RCP2.X (Tier 1)
• Extension of RCP8.5, RCP4.5 and RCP2.X to 2300 (Tier 1, 2)
• Several idealised experiments
CMIP5 – RCP CO2 emissions and concentrations
Key to projections are four “representative concentration pathways”
 RCP8.5, RCP6.0, RCP4.5, and RCP2.X
 The number (8.5, etc) indicates approximate W m-2 radiative forcing by 2100.
 However, these four pathways will have concentrations of GHGs specified (though
corresponding emissions series will be available for use in certain coupled climate-carbon
experiments for those groups that have that capability).
 The RCP8.5 and RCP4.5 are to be “core”, with RCP2.X the next highest priority
Near-term experiments (decadal prediction)
Near-term experiments
The principal near-term experiments are:
• Simulations initialised at 1960, 1965, …., 2005, each of 10 years duration.
Ensemble size of 3 (optional 10) members.
• Extend simulations initialised at 1960, 1980, 2005 to 30 years duration.
RCP4.5 is to be used for the period 2005 – 2035.
The method of initialisation is to be left entirely to the modelling groups.
(Initialisation is one of the major scientific questions.)
Climate models and IPCC AR5 timelines
 Current “rule of thumb” is that models will need to complete submission of
their simulations by late 2010 to have maximum impact in the IPCC AR5
 Impact fades steadily thereafter until no impact perhaps by late 2011
 ACCESS has plans as to what may be delivered to CMIP5 by certain times.
These are quite rubbery as model development time scales are uncertain.
 ACCESS aims to deliver the core long-term experiments in to the CMIP5 in
time for use in AR5.
 Australia will not be delivering to the near-term (decadal prediction) part of
the AR5. No initialisation scheme readily at hand.
 In collaboration with CAWCR SP Research Group, potential to develop
capacity for decadal predictability work in time for delivery to CMIP5 later
Contact
Tony Hirst
Title: Stream leader, ACCESS Stream
Phone: (+61 3 9239 4531)
Email: [email protected]
Web: www.cmar.csiro.au
Contact CSIRO
Phone: 1300 363 400
+61 3 9545 2176
Email: [email protected]
Web: www.csiro.au
www.csiro.au
CSIRO Mk3.5
Mk3.5 – Improvements over Mk3.0
 Physics
•
•
•
•
Improved river routing
Upgraded sea ice numerics
Ocean surface current speed included in wind stress calculation
Improved scheme for oceanic eddy-induced transport
 Solution
• Much reduced drift over that in Mk3.0
(< 0.05C/century)
• Much improved Southern Ocean circulation
Full set of CMIP3 simulations performed
(including 1300 year control)
Surface air temperature change for CMIP3 models
Idealised CMIP forcing (1% p.a. CO2 concentration change)
+3
+2
+1
0
-1
Mk3.5 simulations – Output data
• Availability
1. PCMDI (Mk3.0, Mk3.5 available now)
http://www-pcmdi.llnl.gov/
2. Direct copy on CSIRO server cherax
cherax:~IPCC/data/M/E/T/R/file_name.nc
Where directory is constructed with:
M model version (mk3.0/mk3.5)
E experiment (PICntrl, 20C3M, SRESA2 etc.)
T table (A1a, A2b, O1e etc.)
R ensemble (run1, run2, run3)
2. OPENDAP
(i) Browser:
http://hpsc.csiro.au/cgi-bin/OpenDAP/CMAR_mk3/nph-dods/
Access via a username and password.
(ii) Ferret:
Use http://CMAR_mk3:[email protected]/cgi-bin/OpenDAP/CMAR_mk3/nphdods/ipccdata/M/E/T/R/file_name.nc
(iii) DODS enabled ncks;
Use ncks http://CMAR_mk3:[email protected]/cgi-bin/OpenDAP/CMAR_mk3/nphdods/M/E/T/R/file_name.nc
Mk3.6 – second mode of
rainfall
variability
Modelled – Mk3.6 vs CMIP3 models
Observed
CSIRO Mk3.6
Power spectrum NINO 3.4
Spatial pattern of ENSO SST anomalies
SST anomalies regressed onto 1 stdev NINO 3.4 index
Observed
Mk3.5
Mk3.5A
CMIP5 Model output data
Model output data and storage will be coordinated by PCMDI (LLNL,
California)
 A strict format protocol will be required
 A distributed system will be used
 Main focus will be on providing support for IPCC WG1-type work
 The model outputs will be available for a broader range of research on
request, as for the CMIP3 (IPCC AR4) model outputs
 The model output will be in NetCDF format
 The total model output fields may run into several (many) PB. This may
cause significant download issues for some Australian IPCC projects.
CMIP5 timelines
2009
2010
2011
?
Full emission and
concentration
scenarios to be
made available to
modelling groups
Deadline for
modelling results
to be required to
be used in AR5
analysis studies
2012
2013
?
Modelling results
to about this time
may still be used
in Lead Author
analyses
CMIP5 continues to
accept model results
well after IPCC AR5,
through at least
2013.
Decadal prediction capability in Australia?
Decadal (10-30 year) prediction is a new and major focus of effort
overseas.
 Time scale of greatest interest to planning in a wide range of applications
 Time scale is short enough that differences in the emissions scenarios of
GHGs do not matter much
 Expect a well initialised model to provide improved projections over this
time scale than a non-initialised model (inform initial state versus
underlying trend)
 But not clear how much additional skill is gained by initialisation.
Decadal prediction capability in Australia?
Decadal (10-30 year) prediction is a new and major focus of effort
overseas.
 Time scale of greatest interest to planning in a wide range of applications
 Time scale is short enough that differences in the emissions scenarios of
GHGs do not matter much
 Expect a well initialised model to provide improved projections over this
time scale than a non-initialised model (inform initial state versus
underlying trend)
 But not clear how much additional skill is gained by initialisation.
Decadal prediction is flagged as a new activity in the NFCCS
 Will take significant resources
 In a funding-constrained environment, level of priority will need to be
considered.
CMIP5 and the IPCC AR5
Coupled Model Intercomparison Project 5 (CMIP5)
 Will form the modelling basis on which AR5 will draw
 Will continue past the AR5
 Discussed in detail in Taylor et al. (2009).
 Experiments are designated as “core”, “very high priority”, “high priority”
 Concentrations and emissions of all forcings (GHGs, aerosols, …) to be provided.
 All emissions and GHG concentration scenarios are expected to be available by mid
2009.
 Data storage and access will be coordinated by PCMDI, using a distributed model.
Main focus will be on providing support for IPCC WG1 work.