LMDZ Single Column Model

+ what is it ?+ why is it interesting ?+ List of 1D cases+ how to install and run it ?

M-P Lefebvre and LMDZ team

Explicit simulations, Grid cell, 20-100 m« Large scale »

conditions imposed

Evaluation

Evaluation

Use of 1D casesUse of 1D cases

Observation

Climate model, parameterizations, « single-column » mode

Test case, field campaign experiment

Courtesy F.Hourdin

3D is a collection of many “single column models”, covering earth and interaction with each other through a set of rules known as “large scale dynamics”.

In a 1D model, there is no dynamics. We use observations or model output or idealized forcing to impose forcing at the boundary of the column.

LMDZ model in 1D mode

Surface conditions:Surface fluxes orSurface temperature

Large scale forcings(constant or not):Temperature, humidity,Wind advection

Δx = 50-300 km

Δz = 30m - 1km

z~20km

- We impose large scale conditions.- Duration of the case varies from few hours to few months- We study parameterizations in a given environment.

T (K) Q (g/kg)

Why use SCMs ?

+ simplicity: technical and understanding, usable on any labtop

+ it's a useful tool for parameterization development: shallow convection, deep convection, transition from stratocumulus to cumulus, stable boundary layer, radiation...

+ we can compare results to observations or to explicit simulations (CRM, LES)

+ then we go back to GCM and test new parameterizations ...

+ hierarchy of models: SCM, CRM, AGCM, GCM ...

shallow convection

Arm_cu (diurnal cycle of shallow cumulus over land) Rico (shallow precipitating cumulus over sea) Ayotte (convective boundary layer )

Arm_cu case - Cloud fraction

Stratocumulus and transition to cumulus

Sandu (transition case with 3 options according to variation of SST)• Fire (diurnal cycle of stratocumulus)

Fire case:Cloud fraction (%)

Top: standard versionBad representation because notEnough entrainment at the cloud top

Bottom: version developped by A.Jam

Vertical speed (m/s)

Precipitation (mm/j)

TWPICE Case

Deep convection:

Over ocean:• Toga• case_e (part of Toga)• TWPICE

Deep convection:

Over land:• Hapex• AMMA• Idealized case: eq_rad_conv (RCE)

LES LMDZ_AR4_L39

LMDZ_NP_L70

AMMA case:Thetal tendencies due to all schemes (K/j)

How to proceed ?

+ install LMDZ 3D with install.sh

+ install LMDZ 1D with instal1d.sh. * this script adds some routines specific to 1D* creates phy1D directory* compiles* runs 3 cases (toga, twpice, arm_cu) and show cloud

cover plot

drwxr-xr-x 13 mpllmd lmdjus 4096 Nov 29 17:18 .drwxr-xr-x 10 mpllmd lmdjus 4096 Nov 29 19:32 ..drwxr-xr-x 3 mpllmd lmdjus 4096 Nov 21 16:30 bibiodrwxr-xr-x 3 mpllmd lmdjus 4096 Nov 21 16:30 cosp-rw-r--r-- 1 mpllmd lmdjus 888775 Nov 29 19:29 create_make_gcm.log-rw-r--r-- 1 mpllmd lmdjus 67587 Nov 29 19:27 create_makeg_gcm.logdrwxr-xr-x 3 mpllmd lmdjus 8192 Nov 21 16:30 dyn3ddrwxr-xr-x 3 mpllmd lmdjus 8192 Nov 21 16:30 dyn3dmemdrwxr-xr-x 3 mpllmd lmdjus 8192 Nov 21 16:30 dyn3dpardrwxr-xr-x 3 mpllmd lmdjus 4096 Nov 21 16:30 filtrezdrwxr-xr-x 4 mpllmd lmdjus 97 Nov 29 19:32 griddrwxr-xr-x 4 mpllmd lmdjus 12288 Nov 29 19:23 phy1ddrwxr-xr-x 3 mpllmd lmdjus 4096 Nov 21 16:30 phydevdrwxr-xr-x 4 mpllmd lmdjus 8192 Nov 21 16:30 phylmddrwxr-xr-x 6 mpllmd lmdjus 92 Nov 21 16:30 .svn

Some changes ...in ~/LMDZ20131121.trunk/modipsl/modeles/LMDZ5/libf

= phylmd + 1D specific routines

In phy1d, you can modify the code

Some changes also ...in ~/LMDZ20131121.trunk/1dcases

drwxr-xr-- 8 mpllmd lmdjus 4096 Dec 3 10:28 ammadrwxr-xr-x 4 mpllmd lmdjus 4096 Dec 3 10:50 arm_cudrwxr-xr-x 5 mpllmd lmdjus 4096 Dec 3 11:55 ayottedrwxr-xr-x 3 mpllmd lmdjus 4096 Dec 3 12:12 case_edrwxr-xr-x 3 mpllmd lmdjus 4096 Dec 3 12:14 eq_rd_cvdrwxr-xr-x 5 mpllmd lmdjus 4096 Nov 29 19:29 firedrwxr-xr-x 3 mpllmd lmdjus 4096 Nov 29 19:29 hapex92_initdrwxr-xr-x 4 mpllmd lmdjus 4096 Nov 29 19:29 ricodrwxr-xr-- 5 mpllmd lmdjus 4096 Nov 29 19:29 sandufastdrwxr-xr-- 5 mpllmd lmdjus 4096 Nov 29 19:29 sandurefdrwxr-xr-- 5 mpllmd lmdjus 4096 Nov 29 19:29 sanduslowdrwxr-xr-x 5 mpllmd lmdjus 4096 Nov 29 19:30 togadrwxr-xr-x 4 mpllmd lmdjus 4096 Nov 29 19:31 twpice

Here, you can compile the model and run your favorite case

What can you do in each case directory ?

+ compile with compile.x: choose level number+ profils and forcings (ascii files or netcdf files)+ def files+ readme+ execute with xqt.x or mr file+ get results in netcdf files (histhf.nc)+ compare to LES results in resul_LES

In LMD, we used these cases to develop New Physics version.

For 2 cases, Arm_cu and Rico, we compare results of « standard physics » (CMIP3), « new physics » (CMIP5) and LES model.

Shade= cloud coverContour= specific humidity (g/kg)

Rico case :

Sensitivity Tests to vertical discretization and time step

Thank you !