| 2 | | Before setting up a future simulation, a pre-industrial run will be required to check the radiation balance at the top of the atmosphere. You can find some extra information on the topic at http://forge.ipsl.jussieu.fr/orchidee/wiki/Documentation/VerifyClimate. The basic idea is that for a pre-industrial run the net radiation at the top of the atmosphere should be close to zero. If this is not the case then the albedo of the oceans can be adjusted to mimic several atmospheric processes which are not accounted for. The setting of the variable pmagic that was required to produce a pre-industrial run with zero net-radiation at the top of the atmosphere is also the value for pmagic that needs to used in the present day simulation. It is also a good idea to run a present day climate simulation to check whether the simulated land surface results in an acceptable present day climate. LibIGCM has several tools for this see https://forge.ipsl.jussieu.fr/orchidee/wiki/Documentation/UserGuide/VerifyClimate |
| 3 | | |
| 4 | | Background of this set-up: The aim is to run a 20 year long equilibrium simulation for the year 2100. Orchidee off-line line was used to simulate the land surface in 2100 and now we want to know how the climate looked liked for such a surface. The coupled run is zoomed over Europe, nudged at the edges of Europe uses the CWRR (a.k.a. 11-layer) hydrology and all the DOFOCO features. A set of coupled pre-industrial runs demonstrated that the net-radiation at the top of the atmosphere was close to zero (0.2 Wm2 over 15 years with a monthly std 5.4 Wm2 for a pmagic = 0.000). |
| | 2 | Before setting up a future simulation, a pre-industrial run will be required to check the radiation balance at the top of the atmosphere. You can find some extra information on the topic at http://forge.ipsl.jussieu.fr/orchidee/wiki/Documentation/VerifyClimate. The basic idea is that for a pre-industrial run the net radiation at the top of the atmosphere should be close to zero. If this is not the case then the albedo of the oceans can be adjusted to mimic several atmospheric processes which are not accounted for. The setting of the variable pmagic that was required to produce a pre-industrial run with zero net-radiation at the top of the atmosphere is also the value for pmagic that needs to used in the present day and future simulation (because it partly depends on your specific settings for the land surface). Even if your study does not require the present day climate, it is still a good idea to run a present day climate simulation and check whether the simulated land surface results in an acceptable present day climate. LibIGCM has several tools for this validation task. See https://forge.ipsl.jussieu.fr/orchidee/wiki/Documentation/UserGuide/VerifyClimate |
| | 3 | |
| | 4 | Background of this set-up: The aim is to run a 20 year long equilibrium simulation for the year 2100. Orchidee off-line line was used to simulate the land surface in 2100 and now we want to know how the climate would look like for such a surface. The coupled run is zoomed over Europe, nudged at the edges of Europe, uses the CWRR (a.k.a. 11-layer) hydrology, and all the DOFOCO features. A set of coupled pre-industrial runs demonstrated that the net-radiation at the top of the atmosphere was close to zero (0.2 Wm2 over 15 years with a monthly std 5.4 Wm2 for a pmagic = 0.000). |
| 7 | | CHECK +++ We want a 30-year equilibrium run but if we really use the boundary conditions from 1980 to 2010 we won't get anything near equilibrium given that this is the period in which climate change became very obvious. So we tried to limit the variation by copying the boundary conditions from 2008 to 2012 and cycling over these files to obtain a pseudo-chronology for 1981 to 2010. This approach enables us to run an experiment from 1981 to 2010 which makes LibIGCM happy and at the same time account for the inter-annual variability around 2010 which makes the coupled simulation more realistic. The pseudo-chronologies were aligned for 2010 (2010->2010, 2009->2009, 2008->2008, 2012->2007, 2011->2006, 2010->2005, etc). The original source files are the same as those used in the pre-industrial experiment and are stored at /ccc/work/cont003/dsm/p86ipsl/IGCM/INIT/ATM/LMDZOR/ATM/AMIP/. The cyclic boundary conditions for ocean surface temperature and sea ice extent are stored at /ccc/work/cont003/dofoco/dofoco/INPUT_FILES/OCEAN_COMP/. The same adjustments were made for the boundary condition files for ozone. The original source files are the same as those used in the pre-industrial experiment and are stored at /ccc/work/cont003/dsm/p86ipsl/IGCM/INIT/ATM/LMDZOR/Ozone/HYBRIDE/v2.clim/*.new.nc. These cyclic files to be used in this set-up can be found at /ccc/work/cont003/dofoco/dofoco/INPUT_FILES/ATM_COMP/OZON/.+++ |
| 8 | | |
| 9 | | LMDZOR was installed once more to avoid any conflicts between the boundary files of the pre-industrial, present day, and future simulations. Hence, one installation will be used for the pre-industrial runs (and will thus use the pre-industrial boundary conditions), the other installation is to be used for present day simulations and the third installation is used for the future simulations. For all simulations an AMIP set-up was chosen. CHECH +++ Note that we use ERAI wind fields for nudging but AMIP for the other boundary conditions. It would be better to use ERAI for all boundary conditions but that is only possible for more recent simulations. This set-up comes with acceptable BC between 1870 and 2100 which allows us to focus on the climate and reduce issues with sea surface temperature, sea ice and aerosol concentrations. So copy the amip config.card to define the job that will create the BC +++ |
| 10 | | {{{ |
| 11 | | cd config/LMDZOR_v5.2/ |
| 12 | | cp EXPERIMENTS/LMDZ/CREATE_amip/config.card ./ |
| 13 | | }}} |
| 14 | | The following changes were made to the config.card: |
| 15 | | (1) Add a suffix, i.e., -2100 (but keep the grid dimensions 128x118x39) to the job name so that the pre-industrial, present day and future boundary files will not interfere with each other on the store directory |
| 16 | | {{{ |
| 17 | | JobName= ELI-128x118x39-2100 |
| 18 | | }}} |
| 19 | | (2) Set the begin date to the earliest year available. We are planning 20 year long equilibrium simulations but we are not sure whether it will take 20 or 30 years so we simulate the BC for 30 years to be on the safe side. |
| 20 | | {{{ |
| 21 | | DateBegin=2101-01-01 |
| 22 | | DateEnd=2130-12-31 |
| 23 | | }}} |
| 24 | | (3) There is no need to manually create a directory for this experiment. When you use ./../../util/ins_job the script will create a directory with a copy of the config.card as well as the COMP, DRIVER and PARAM folder. |
| 25 | | |
| 26 | | The following, further, changes were made to the COMP/lmdz.card: |
| 27 | | |
| 28 | | |
| 29 | | +++WORKING ON THIS SECTION+++ |
| 30 | | |
| 31 | | No observations available for this period so we need to use simulations. We will use AR5 simulations from the IPSL ESM IPSL-CM. Archives of these simulations can be found at the IPSL contact the CMIP team to learn the difference between the different simulations. |
| | 7 | Obviously, observations are not yet available for 2100 so we will use simulations. We will use AR5 simulations from the Earth System model of the IPSL called IPSL-CM. Archives of these simulations can be found at the IPSL https://forge.ipsl.jussieu.fr/igcmg/wiki/IPSLCMIP5/Centennal/IPSLCM5A-LR. Simulations with a higher version number typically denote simulations for which previous problems were fixed. We used |
| | 8 | |
| | 21 | |
| | 22 | CHECK +++ We want a 30-year equilibrium run but if we really use the boundary conditions from 1980 to 2010 we won't get anything near equilibrium given that this is the period in which climate change became very obvious. So we tried to limit the variation by copying the boundary conditions from 2008 to 2012 and cycling over these files to obtain a pseudo-chronology for 1981 to 2010. This approach enables us to run an experiment from 1981 to 2010 which makes LibIGCM happy and at the same time account for the inter-annual variability around 2010 which makes the coupled simulation more realistic. The pseudo-chronologies were aligned for 2010 (2010->2010, 2009->2009, 2008->2008, 2012->2007, 2011->2006, 2010->2005, etc). The original source files are the same as those used in the pre-industrial experiment and are stored at /ccc/work/cont003/dsm/p86ipsl/IGCM/INIT/ATM/LMDZOR/ATM/AMIP/. The cyclic boundary conditions for ocean surface temperature and sea ice extent are stored at /ccc/work/cont003/dofoco/dofoco/INPUT_FILES/OCEAN_COMP/. The same adjustments were made for the boundary condition files for ozone. The original source files are the same as those used in the pre-industrial experiment and are stored at /ccc/work/cont003/dsm/p86ipsl/IGCM/INIT/ATM/LMDZOR/Ozone/HYBRIDE/v2.clim/*.new.nc. These cyclic files to be used in this set-up can be found at /ccc/work/cont003/dofoco/dofoco/INPUT_FILES/ATM_COMP/OZON/.+++ |
| | 23 | |
| | 24 | LMDZOR was installed once more to avoid any conflicts between the boundary files of the pre-industrial, present day, and future simulations. Hence, one installation will be used for the pre-industrial runs (and will thus use the pre-industrial boundary conditions), the other installation is to be used for present day simulations and the third installation is used for the future simulations. For all simulations an AMIP set-up was chosen. CHECH +++ Note that we use ERAI wind fields for nudging but AMIP for the other boundary conditions. It would be better to use ERAI for all boundary conditions but that is only possible for more recent simulations. This set-up comes with acceptable BC between 1870 and 2100 which allows us to focus on the climate and reduce issues with sea surface temperature, sea ice and aerosol concentrations. So copy the amip config.card to define the job that will create the BC +++ |
| | 25 | {{{ |
| | 26 | cd config/LMDZOR_v5.2/ |
| | 27 | cp EXPERIMENTS/LMDZ/CREATE_amip/config.card ./ |
| | 28 | }}} |
| | 29 | The following changes were made to the config.card: |
| | 30 | (1) Add a suffix, i.e., -2100 (but keep the grid dimensions 128x118x39) to the job name so that the pre-industrial, present day and future boundary files will not interfere with each other on the store directory |
| | 31 | {{{ |
| | 32 | JobName= ELI-128x118x39-2100 |
| | 33 | }}} |
| | 34 | (2) Set the begin date to the earliest year available. We are planning 20 year long equilibrium simulations but we are not sure whether it will take 20 or 30 years so we simulate the BC for 30 years to be on the safe side. |
| | 35 | {{{ |
| | 36 | DateBegin=2101-01-01 |
| | 37 | DateEnd=2130-12-31 |
| | 38 | }}} |
| | 39 | (3) There is no need to manually create a directory for this experiment. When you use ./../../util/ins_job the script will create a directory with a copy of the config.card as well as the COMP, DRIVER and PARAM folder. |
| | 40 | |
| | 41 | The following, further, changes were made to the COMP/lmdz.card: |
| | 42 | |
| | 43 | |
| | 44 | +++WORKING ON THIS SECTION+++ |
| | 45 | |
| | 46 | |
