WRF-ARW User's Guide - University Corporation for Atmospheric

424 Pages·2014·37.31 MB·English

A RW
Version 3 Modeling System User’s Guide
July 2014
Mesoscale & Microscale Meteorology Division • National Center for Atmospheric Research
!
Foreword

This User’s Guide describes the Advanced Research WRF (ARW) Version 3.6 modeling
system, released in April 2014. As the ARW is developed further, this document will be
continuously enhanced and updated. Please send feedback to [e-mail].

This document is complementary to the ARW Tech Note
(http://www.mmm.ucar.edu/wrf/users/docs/arw_v3.pdf), which describes the equations,
numerics, boundary conditions, and nesting etc. in greater detail.

Highlights of updates to WRFV3.6 include:

• WRF model:
New physics:
o Sub-tiling capability for Noah LSM (contributed by Dan Li of Princeton)
o Lake model (contributed by Hongping Gu of IAP China and Jiming Jin of
Utah State University)
o Full and ‘fast’ versions of HUJI spectral bin microphysics (contributed by
Alex Khain and Barry Lynn of Hebrew University of Jerusalem, Israel)
o Improved aerosol input capability for use in RRTMG and new Goddard
radiation options (contributed by Jose Ruiz-Arias of University of Jaen,
Spain)
o Sub-grid cloud fraction from Kain-Fritsch scheme (contributed by Alapaty
and Herwehe of EPA)
o Vertical structure function in SKEBS (contributed by J. Berner of NCAR)
Others:
o Improved wind farm parameterization (contributed by Pedro Jimenez of
Spain, and Henning Heiberg-Andersen of Uni Rerearch, Norway)
o Improvement to NoahMP
o WRF-Hydro 2.0 (contributed by NCAR/RAL)
o Diagnostic option (contributed by AFWA)
o Faster netCDF write (contributed by Jim Abeles of IBM and J. Michalakes of
NCEP)
o 12-montly, 30-sec Leaf-Area Index dataset derived from MODIS (contributed
by M. Barlage of NCAR/RAL)
o 15-seconds MODIS landuse dataset (contributed by Patrick Broxton and
Xubin Zeng of Univ of Arizona)
• WRF-DA updates:
o New instruments which can be assimilated: Meteosat SEVIRI (IR radiance),
AIREP humidity and Metop-B instruments (IASI, AMSU-A and MHS)
o Observation thinning for conventional obs in ASCII format
o Dual-resolution hybrid assimilation
o Radiative transfer code updated: CRTM is up to 2.1.3, and RTTOV 11.1
• WRF-Chemistry
o Improvement on existing code and packages.
For the latest version of this document, please visit the ARW Users’ Web site at
http://www.mmm.ucar.edu/wrf/users/.

Contributors to this guide:
Wei Wang, Cindy Bruyère, Michael Duda, Jimy Dudhia, Dave Gill, Michael Kavulich,
Kelly Keene, Hui-Chuan Lin, John Michalakes, Syed Rizvi, Xin Zhang, Judith Berner
and Kate Smith
Contributors to WRF-Fire chapter:
Jonathan D. Beezley, Janice L. Coen, and Jan Mandel
Contributors to UPP section:
Hui-Ya Chuang, Nicole McKee, Tricia Slovacek, Jamie Wolff, and Kate Smith

Special Acknowledgment:
We gratefully acknowledge the late Dr. Thomas T. Warner for his years of research,
development, instruction, leadership, and motivation in the field of NWP modeling.
CONTENTS

1. Overview
− Introduction ................................................................................. 1-1
− The WRF Modeling System Program Components ..................... 1-2

2. Software Installation
− Introduction .................................................................................. 2-1
− Required Compilers and Scripting Languages ............................. 2-2
− Required/Optional Libraries to Download .................................... 2-3
− Post-Processing Utilities ............................................................... 2-4
− UNIX Environment Settings ......................................................... 2-4
− Building the WRF Code ................................................................ 2-5
− Building the WPS Code ................................................................ 2-6
− Building the WRFDA Code (for 3DVAR) ...................................... 2-7
− Building the WRFDA Code (for 4DVAR) ………………………….. 2-9

3. The WRF Preprocessing System (WPS)
− Introduction ................................................................................. 3-1
− Function of Each WPS Program ................................................. 3-2
− Installing the WPS ....................................................................... 3-4
− Running the WPS ........................................................................ 3-7
− Creating Nested Domains with the WPS .................................. 3-20
− Selecting Between USGS and MODIS-based
Land Use Data .......................................................................... 3-22
− Selecting Static Data for the Gravity Wave Drag Scheme ........ 3-23
− Using Multiple Meteorological Data Sources ............................ 3-23
− Alternative Initialization of Lake SSTs…………………………… 3-26
− Parallelism in the WPS .............................................................. 3-28
− Checking WPS Output .............................................................. 3-29
− WPS Utility Programs ................................................................ 3-30
− Writing Meteorological Data to the Intermediate Format ........... 3-33
− Creating and Editing Vtables ..................................................... 3-35
− Writing Static Data to the Geogrid Binary Format ..................... 3-37
− Creating an Urban Fraction Field from NLCD Data .................. 3-40
− Description of Namelist Variables ............................................. 3-42
− Description of GEOGRID.TBL Options ..................................... 3-47
− Description of index Options ..................................................... 3-50
− Description of METGRID.TBL Options ...................................... 3-53
− Available Interpolation Options in Geogrid and Metgrid ............ 3-56
− Land Use and Soil Categories in the Static Data ...................... 3-59
− WPS Output Fields .................................................................... 3-61

4. WRF Initialization
− Introduction ................................................................................. 4-1
− Initialization for Ideal Cases ........................................................ 4-3

WRF-ARW V3: User’s Guide i
CONTENTS

− Initialization for Real Data Cases ................................................ 4-6

5. WRF Model
− Introduction ................................................................................ 5-1
− Installing WRF ............................................................................ 5-2
− Running WRF ............................................................................. 5-8
− Examples of namelists for various applications ........................ 5-30
− Check Output ........................................................................... 5-33
− Trouble Shooting ....................................................................... 5-34
− Physics and Dynamics Options ................................................. 5-34
− Summary of PBL Physics Options………………………………. 5-47
− Summary of Microphysics Options………………………………. 5-48
− Summary of Cumulus Parameterization Options………………. 5-50
− Summary of Radiation Physics Options.................................... 5-51
− Description of Namelist Variables ............................................. 5-54
− WRF Output Fields .................................................................. 5-102

6. WRF Data Assimilation
− Introduction ................................................................................. 6-1
− Installing WRFDA for 3D-Var Run…. .......................................... 6-4
− Installing WRFPLUS and WRFDA for 4D-Var Run ..................... 6-8
− Running Observation Preprocessor (OBSPROC) ...................... 6-9
− Running WRFDA ....................................................................... 6-13
− Radiance Data Assimilations in WRFDA .................................. 6-21
− Precipitation Data Assimilation in WRFDA 4D-Var…………….. 6-31
− Updating WRF boundary conditions ......................................... 6-34
− Running gen_be ........................................................................ 6-36
− Additional WRFDA Exercises .................................................... 6-39
− WRFDA with Multivariate Background Error (MBE) Statistics…6-42
− WRFDA Diagnostics ................................................................. 6-43
− Hybrid Data Assimilation ........................................................... 6-47
− ETKF Data Assimilation............................................................. 6-51
− Description of Namelist Variables ............................................. 6-56

7. Objective Analysis (OBSGRID)
− Introduction ................................................................................. 7-1
− Program Flow .............................................................................. 7-2
− Source of Observations ............................................................... 7-3
− Objective Analysis techniques in OBSGRID ............................... 7-4
− Quality Control for Observations ................................................. 7-6
− Additional Observations .............................................................. 7-7
− Surface FDDA option .................................................................. 7-7
− Objective Analysis on Model Nests ............................................. 7-8

WRF-ARW V3: User’s Guide ii
CONTENTS

− How to run OBSGRID ................................................................. 7-8
− Output Files ............................................................................... 7-10
− Plot Utilities ............................................................................... 7-13
− Observations Format ................................................................. 7-15
− OBSGRID Namelist ................................................................... 7-18

8. WRF Software
− WRF Build Mechanism ................................................................ 8-1
− Registry ....................................................................................... 8-5
− I/O Applications Program Interface (I/O API) ............................ 8-14
− Timekeeping .............................................................................. 8-14
− Software Documentation ........................................................... 8-15
− Performance .............................................................................. 8-15

9. Post-Processing Programs
− Introduction ................................................................................. 9-1
− NCL . ........................................................................................... 9-2
− RIP4 ......................................................................................... 9-20
− ARWpost ................................................................................... 9-29
− UPP ......................................................................................... 9-36
− VAPOR ...................................................................................... 9-59

10. Utilities and Tools
− Introduction ............................................................................... 10-1
− read_wrf_nc .............................................................................. 10-1
− iowrf . ......................................................................................... 10-5
− p_interp ..................................................................................... 10-6
− TC Bogus Scheme .................................................................... 10-9
− v_interp ................................................................................... 10-11
− proc_oml.f ............................................................................... 10-13
− Tools ....................................................................................... 10-14

Appendix A: WRF-Fire
− Introduction ................................................................................. A-1
− WRF_Fire in idealized cases ...................................................... A-3
− Fire variables in namelist.input ................................................... A-4
− namelist.fire ................................................................................. A-5
− Running WRF_Fire on real data ................................................. A-6
− Fire state variables .................................................................... A-12
− WRF-Fire software ................................................................... A-12

WRF-ARW V3: User’s Guide iii
CONTENTS

WRF-ARW V3: User’s Guide iv
OVERVIEW

Chapter 1: Overview

Table of Contents
• Introduction
• The WRF ARW Modeling System Program Components

Introduction
The Advanced Research WRF (ARW) modeling system has been in development for the
past few years. The current release is Version 3, available since April 2008. The ARW is
designed to be a flexible, state-of-the-art atmospheric simulation system that is portable
and efficient on available parallel computing platforms. The ARW is suitable for use in a
broad range of applications across scales ranging from meters to thousands of kilometers,
including:
• Idealized simulations (e.g. LES, convection, baroclinic waves)
• Parameterization research
• Data assimilation research
• Forecast research
• Real-time NWP
• Hurricane research
• Regional climate research
• Coupled-model applications
• Teaching
The Mesoscale and Microscale Meteorology Division of NCAR is currently maintaining
and supporting a subset of the overall WRF code (Version 3) that includes:
• WRF Software Framework (WSF)
• Advanced Research WRF (ARW) dynamic solver, including one-way, two-way
nesting and moving nest.
• The WRF Preprocessing System (WPS)
• WRF Data Assimilation (WRF-DA) system which currently supports 3DVAR
4DVAR, and hybrid data assimilation capabilities
• Numerous physics packages contributed by WRF partners and the research
community
• Several graphics programs and conversion programs for other graphics tools
And these are the subjects of this document.

WRF-ARW V3: User’s Guide 1-1
OVERVIEW

The WRF modeling system software is in the public domain and is freely available for
community use.
The WRF Modeling System Program Components
The following figure shows the flowchart for the WRF Modeling System Version 3.

As shown in the diagram, the WRF Modeling System consists of these major programs:
• The WRF Preprocessing System (WPS)
• WRF-DA
• ARW solver
• Post-processing & Visualization tools
WPS
This program is used primarily for real-data simulations. Its functions include 1) defining
simulation domains; 2) interpolating terrestrial data (such as terrain, landuse, and soil

WRF-ARW V3: User’s Guide 1-2