Release notes

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Upcoming

Features under development:

• Aerosol chemistry (expected February 2018)

• Biometeorological analysis products (expected January 2018)

• Indoor climate and energy demand model (expected February 2018)

• Multi-agent system for humans in urban environments (expected May 2018)

• RANS mode: TKE-epsilon turbulence closure for urban simulations (expected January 2018)

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Version 5.0 - December 15, 2017

New features:

• Chemistry model (PALM-4U): A gas-phase chemistry has been implemented.

• Cloud microphysics (PALM): Advanced bulk microphysics implemented. This basically involves two additional prognostic equations for the cloud droplet number concentration, and the cloud water content as well as aerosol activation schemes.

• GUI tools (PALM): Graphical helper tools have been added (PALM grid finder, palm_gf; PALM watchdog, palm_wd, PALM job manager, palm_jm).

• INIFOR (PALM-4U): Forcing by COSMO-DE large-scale data is realized via NetCDF interface and preprocessing tool INIFOR.

• Interface for reading NetCDF input data: (PALM-4U): Input data (e.g. building heights, land surface classification, etc.) are not read from NetCDF driver files.

• Lagrangian cloud model: (PALM): Splitting/merging algorithm implemented.

• Land surface scheme (PALM):
  • Support for water and paved surfaces added (details).
  • Revised skin layer concept and soil model configuration (details).

• LES-LES self-nesting (PALM-4U): Multi-stage LES-LES nesting is realized for most quantities (except chemistry) (details). Also, two different 1D vertical nesting schemes are available.

• Model steering (PALM): The old scripts mrun and mbuild have been removed in favor of more user-friendly scripts palmrun and palmbuild.

• Radiation model (PALM): Coupling to RRTMG radiation code realized. RRTMG is now shipped with PALM.

• Radiative transfer (PALM-4U): Radiative transfer in the urban canopy layer, including multiple reflections between buildings and shading of tall vegetation. Can also be used in complex terrain.

• Spin-up (PALM-4U): A spin-up mechanism is available for running land surface model, urban surface model and radiation scheme independently from atmosphere to generate steady-state soil and wall temperatures for initialization.

• Synthetic turbulence generator (PALM): A turbulence gerator can be used instead of turbulence recycling for non-cyclic inflow conditions

• Testsuite (PALM): New svn commits are now automatically tested.

• Urban surface scheme (PALM-4U): An energy balance solver for buildings and a wall material model.

• Wind turbine model (PALM): A wind turbine model was implemented (details).

Major changes:

• Humidity vs scalar: Humidity and scalar are now separated.

• Multigrid solver (PALM): Optimized multi-grid pressure solver is implemented.

• Non-cycle inflow: major changes and improvements for non-cyclic turbulent inflow and turbulence recycling.

• palmrungui: the mrun GUI was re-designed in python and renamed to palmrungui.

• Surface layer: Three different methods are now available to calculate surface-layer scaling variables and fluxes. This basically involves the calculation of the Obukhov length. Three different methods are not available ("old" circular method, Newton interation, and look-up table) (wiki:doc/tec/bc details]).

• Surface treatment:

• Topography implementation: Topography is now considered via flag arrays instead of 2D index arrays. Overhanging structures like bridges are now possible, i.e., the limitation of surface-mounted topography does not exist anymore. A topography filter was implemented that fills holes that consist of only one grid point details).

Bugs fixed:

See changelog 2017 and changelog 2013-2016.

Known bugs:

• Calculation of aerodynamic resistance for building walls needs further adjustment

• LES-LES nesting remains unstable at high grid aspect ratios (so far only tested for a ratio of 10:1)

• Nesting and restarts do not work for chemistry yet

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Version 4.0 - January 28, 2015

New features:

• Progress bar (PALM): Informative messages during execution and progress bar added

• Land surface model (PALM): Beta version has been implemented

• Radiation model (PALM): Simple clear-sky radiation model

Major changes:

• Canopy model: Canopy model is modularized and controlled by seperate NAMELIST

• General changes in code layout:
  • ONLY attribute added to all USE statements
  • KIND parameter added to all INTEGER/REAL declarations
  • comment fields for explaining variables added

• Lagrangian particle model: Completely revised with improved performance and less demand of memory

• Large-scale forcing / nudging: Some extensions

• Parallel NetCDF: Peformance optimization for parallel NetCDF on Cray XC systems

• Performance: Code modifications to allow run on 10.000 cores and more

Bugs fixed:

changelog 2013-2016

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