This project has been approved for unlimited distribution as LLNL-CODE-813369. This is a version of the WRF model with the immersed boundary method for representing complex terrain. This version of WRF allows simulation over complex terrain without using a terrain-following coordinate. NOTICE This work was produced at the Lawrence Livermore National Laboratory (LLNL) and University of California, Berkeley, under contract no. DE-AC52-07NA27344 (Contract 44) between the U.S. Department of Energy (DOE) and Lawrence Livermore National Security, LLC (LLNS) for the operation of LLNL. Copyright is reserved to Lawrence Livermore National Security, LLC for purposes of controlled dissemination, commercialization through formal licensing, or other disposition under terms of Contract 44; DOE policies, regulations and orders; and U.S. statutes. The rights of the Federal Government are reserved under Contract 44. DISCLAIMER This work was prepared as an account of work sponsored by an agency of the United States Government. NEITHER THE UNITED STATES GOVERNMENT NOR LAWRENCE LIVERMORE NATIONAL SECURITY, LLC, NOR REGENTS OF UNIVERSITY OF CALIFORNIA, NOR ANY OF THEIR EMPLOYEES, MAKES ANY WARRANTY, EXPRESS OR IMPLIED, OR ASSUMES ANY LIABILITY OR RESPONSIBILITY FOR THE ACCURACY, COMPLETENESS, OR USEFULNESS OF ANY INFORMATION, APPARATUS, PRODUCT, OR PROCESS DISCLOSED, OR REPRESENTS THAT ITS USE WOULD NOT INFRINGE PRIVATELY-OWNED RIGHTS. THIS SOFTWARE IS PROVIDED BY LAWRENCE LIVERMORE NATIONAL SECURITY, LLC "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or Lawrence Livermore National Security, LLC or Regents of the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or Lawrence Livermore National Security, LLC, and shall not be used for advertising or product endorsement purposes. NOTIFICATION OF COMMERCIAL USE Commercialization of this product is prohibited without notifying the Department of Energy (DOE) or Lawrence Livermore National Security or the Regents of the University of California.

{"references": ["Lundquist, K.A., Chow, F.K., and J.K. Lundquist, 2010. An immersed boundary method for the Weather Research and Forecasting model. Monthly Weather Review 138(3), 796-817. DOI:10.1175/2009MWR2990.1", "Lundquist, K.A., Chow, F.K., and J.K. Lundquist. 2012. An immersed boundary method enabling large-eddy simulations of flow over complex terrain in the WRF model. Monthly Weather Review, 140(12), 3936-3955. DOI: 10.1175/MWR-D-11-00311.1", "Bao, J., F.K. Chow, and K.A. Lundquist, 2018. Large-eddy simulation over complex terrain using an improved immersed boundary method in the Weather Research and Forecasting model. Monthly Weather Review, 146, 2781-2797. DOI: 10.1175/MWR-D-18-0067.1", "Arthur, R.S., K.A. Lundquist, J.D. Mirocha, and F.K. Chow, 2018. Topographic effects on radiation in the WRF Model with the immersed boundary method: implementation, validation, and application to complex terrain. Monthly Weather Review, 146, 3277-3292. DOI: 10.1175/MWR-D-18-0108.1", "Wiersema, D.J., K.A. Lundquist, and F.K. Chow, 2020. Mesoscale to microscale simulations over complex terrain with the immersed boundary method in the Weather Research and Forecasting model. Monthly Weather Review, 148, 577-595. DOI: 10.1175/MWR-D-19-0071.1", "Arthur, R.S., K.A. Lundquist, D.J. Wiersema, J. Bao, and F.K. Chow, 2020. Evaluating implementations of the immersed boundary method in the Weather Research and Forecasting model. Monthly Weather Review, 148, 2087-2109. DOI: 10.1175/MWR-D-19-0219.1"]}

An updated version of this code may be available at https://github.com/LLNL/WRF-IBM. This work was partially supported by the LLNL Laboratory Directed Research and Development Program as project 18-ERD-049, the LLNL Lawrence Graduate Scholars Program, and the LLNL postdoctoral program.