The University of Washington
Planetary Boundary Layer Model

UWPBL 4.1

UWPBL 4.1 is an integrated package of subroutines for the study of the Planetary Boundary Layer (PBL). These subroutines include a modified-Ekman model in the midlatitudes available in its direct and inverse form, as well as a mixed layer model in the Tropics. They can be run easily on the SeaWinds-on-QuikSCAT and SeaWinds-on-Midori II L2B wind vector products to produce surface pressure fields and other fields of relevant PBL quantities.

You might already be familiar with version 4.0 of UWPBL which included a gradient wind correction that was shown to significantly improve the representation of highs and lows (curved contours) in surface pressure fields (Patoux, J. and R.A. Brown, 2002: A Gradient Wind Correction for Surface Pressure Fields Retrieved from Scatterometer Winds, J. Appl. Meteor., 41, 133-143) (Download PDF)

UWPBL 4.0 also included a PBL model for the Tropics taking into account the entrainment at the top of the boundary layer (Patoux, J. and R.A. Brown, 2002: Global Pressure Fields from Scatterometer Winds, J. Appl. Meteor., 42, 813-826) (Download PDF)

These 2004 improvements enabled us to produce pole-to-pole, swath-long pressure fields from SeaWinds surface wind fields.

The new version of the model (UWPBL 4.1, released August 2005) has identical physics. However, because many users have complained about the fact that UWPBL 4.0 and previous versions contained calls to BLAS, LAPACK, and NAG subroutines, I have rewritten the whole package to be self-sufficient and make only calls to internal subroutines (variations on "Numerical Recipes"). Hopefully this new version will be more portable and easier to compile. It also has a better interpolation scheme, and a better matrix inversion scheme for retrieving pressures. Users who have some experience with version 4.0 will find this new version significantly faster.

We are currently working on a Linux Makefile for UWPBL (stay tuned).

Finally, we are hoping to be working on version 5.0 of the model some time in 2006 (pending funding). The future version will contain an improved PBL parameterization taking into account advective terms in the midlatitudes, and a better characterization of entrainment and boundary layer height in the Tropics.

Three main products are offered in the UWPBL package:

A point direct model which calculates the surface stress and surface wind from a value of the geostrophic wind at the top of the boundary layer.

A point inverse model which calculates the geostrophic wind from a value of the surface wind.

A pressure retrieval model which calculates the surface pressure pattern corresponding to a swath of SeaWinds L2B surface wind vectors.

Download

UWPBL 4.1 subroutines (4.9 Mb, tar.gz) This tar contains Fortran source code, a Makefile and sample inputs in one directory, Uwpbl41.

User's manual (PDF, 1.4 Mb)

Important!

Please register to receive updates about new and improved PBL software as it becomes available. This form may also be used to submit bug reports.

Problems or questions, please contact:

Jérôme Patoux
Department of Atmospheric Sciences
University of Washington
Seattle, WA 98195
jerome@atmos.washington.edu