EnKF_lorenz

EnKF, EnKS, and ES implementation with lorenz'63 equations as used in Evensen (1997, 2000, 2009ab). The code allows for testing various EnKF schemes with highly nonlinear dynamics.

Evensen, G. Advanced data assimilation for strongly nonlinear dynamics. Mon. Weather Rev., 125: 1342-1354, 1997. doi:10.1175/1520-0493(1997)125%3C1342:ADAFSN%3E2.0.CO;2

Evensen, G. and P. J. van Leeuwen. An ensemble Kalman smoother for nonlinear dynamics. Mon. Weather Rev., 128:1852-1867, 2000. doi:10.1175/1520-0493(2000)128<1852:AEKSFN>2.0.CO;2

Evensen, G. The ensemble Kalman filter for combined state and parameter estimation. IEEE Control Systems Magazine, 29(3):83–104, 2009a. doi: doi:10.1109/MCS.2009.932223

Evensen, G. Data Assimilation: The Ensemble Kalman Filter. Springer, 2nd edition, 2009b. doi:10.1007/978-3-642-03711-5

Installation:

1. Building the Project

If you plan to collaborate or contribute anything to the project, use the Advanced Installation option.

1a. Basic installation

Create a directory to clone the three following repositories:

git clone [email protected]:geirev/EnKF_lorenz.git
git clone [email protected]:geirev/EnKF_sampling.git
git clone [email protected]:geirev/EnKF_analysis.git

After cloning, the directory structure should look like:

.
├── EnKF_analysis
└── EnKF_sampling
└── EnKF_lorenz

1b. Advanced installation

Make a personal github account unless you already have one. Fork the three repositorys listed above. Next clone the repositories and set upstream to the original repositories where you need to replace with your github userid

git clone [email protected]:<userid>/EnKF_lorenz.git
pushd EnKF_lorenz
git remote add upstream https://github.com/geirev/EnKF_lorenz
#or, if you have set up git-ssh
#git remote add upstream git://github.com:geirev/EnKF_lorenz
popd

git clone [email protected]:<userid>/EnKF_analysis.git
pushd EnKF_analysis
git remote add upstream https://github.com/geirev/EnKF_analysis
#or, if you have set up git-ssh
#git remote add upstream git://github.com:geirev/EnKF_analysis
popd

git clone [email protected]:<userid>/EnKF_sampling.git
pushd EnKF_sampling
git remote add upstream https://github.com/geirev/EnKF_sampling
#or, if you have set up git-ssh
#git remote add upstream git://github.com:geirev/EnKF_sampling
popd

If you are new to Git, read the section Git instructions

2. Required Packages

Linux

sudo apt-get update
sudo apt-get install libblas-dev liblapack-dev gfortran

Mac

brew install gcc openblas lapack

Note: You must have Homebrew installed to install packages using brew

3. Compile the EnKF_sampling library

Navigate to the lib folder of the EnKF_sampling repository:

cd EnKF_sampling/lib

then compile and place all the .o files as well as libanalysis.a into the build directory of the EnKF_lorenz repository using:

make BUILD=../../EnKF_lorenz/build

4. Compile the EnKF_analysis library

Navigate to the lib folder of the EnKF_analysis repository:

cd EnKF_analysis/lib

then compile and place all the .o files as well as libanalysis.a into the build directory of the EnKR_lorenz repository using:

make BUILD=../../EnKF_lorenz/build

5. Compile the EnKF_lorenz library

Linux

Navigate to the src folder of the EnKF_lorenz repository:

cd EnKF_lorenz/src

then compile and install the executable in the target directory, defaulting to $HOME/bin:

make BINDIR=$HOME/bin

Mac

Navigate to the src folder of the EnKF_lorenz repository:

cd EnKF_lorenz/src

then edit the following line in EnKF_lorenz/src/makefile from:

LIBS = ./libenkfanalysis.a -llapack -lblas -llapack 

to:

LIBS = ./libenkfanalysis.a -llapack -lblas -llapack 

then compile and install the executable in the target directory, defaulting to $HOME/bin:

make BINDIR=$HOME/bin

6. Run the Project

Linux

Navigate to the run directory of the EnKF_lorenz repository:

cd EnKF_lorenz/run

and run:

lorenz

Mac

Create the /usr/local/bin directory which allows the lorenz command to be ran from anywhere on the local file system:

mkdir -p /usr/local/bin

then create a symlink for $HOME/bin/lorenz to /usr/local/bin

ln -s $HOME/bin/lorenz /usr/local/bin/

then run the project:

cd EnKF_lorenz/run
lorenz

7. Plotting

If you have tecplot (tec360) there are .lay and .mcr files in the run directory. Otherwise the output files can be plotted by any software like gnuplot etc.