Comcot

COMCOT User Manual
Version 1.6
(Drafted on Sep 19 2006) (Updated on Feb 26 2007)

School of Civil and Environmental Engineering, Cornell University Ithaca, NY 14853, USA

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Journey of COMCOT
COMCOT, COrnell Multigrid COupled Tsunami model, originated from the work of S.N. Seo based on Shuto’s model (Aug.10, 1993) and Yongsik Cho arranged version 1.0 (Aug.10, 1993). A significantimprovement was achieved by Seung-Buhm Woo (1999, 3). Many features, including nonlinear model, Automatic Initial surface interpolation, general grid matching and user interface, were introduced and finally formed version 1.4. However, at this stage, the code was still not well organized and there were limitations in many aspects (e.g., grid setup, initial condition ...), especially efficiency,capability and flexibility. The code, at that time, was written in Fortran 77 and inconveniently, needed to be recompiled for each new simulation. Many achievements were made on COMCOT during this period, such as the successful simulations of 1960 Chile Tsunami and 1986 Taiwan Hua-lien tsunami, involving the calculations of runup and inundation. The coming of Fortran 90 gave a new power to the programmingof this code. With the helps of many others, especially Tom Logan (ARSC), Steven Lantz (Cornell) and Philip L.-F. Liu (Cornell), further improvements and modifications were introduced by Xiaoming Wang (2003), which yielded version 1.5. The most significant progress is the migration from Fortran 77 to Fortran 90, allowing dynamic allocation of memory. Parameter module was introduced, making thecode much neat and readable. And subroutines dealing with nonlinear equations were also optimized to get a better efficiency by Tom Logan (ARSC, 2003). Furthermore, many redundant or unnecessary subroutines were either removed or combined together, including subroutines pqstill, pqtotal, mass, mass_s, mass_c, moment, momt_s, momt_c, ini_mvd, jnzoa, jnqoa, et_o_prt, et_a_prt, et_b_prt, etc. Somesubroutines were renovated or completely rewritten, including subroutines involving parameter input and data output. Old parameter setup files, comcot_common.inc and comcot_v_1_4.inc, were removed and their data entries were incorporated into comcot_v_1_4.ctl. In addition, new features were added in version 1.5, like Cartesian coordinate support for the 1st level grid (layer 1), submarine landslidemodel, Okada’s fault model, given static initial surface profile, given time history data input in incident wave maker (used for benchmark problem 2 in Catalina Workshop 2003). Unlike its previous versions which only allow one-to-one grid hierarchy (each grid can contain only one sub-level grid), in version 1.5, 1st level grid (layer 1) can employ up to 4 2nd level grids (layer 2s) althoughsub-level grids still use one-to-one grid hierarchy. This gives more flexibility for a simulation if multiple sub-regions are of interest. The code was compacted from about 5,000 lines to roughly 3,700 lines with enhanced capability, efficiency and flexibility. However, the development of version 1.5 was an on-going process. With new bugs identified and new features added in, the code was modifiedfrequently on different requirements, yielding several variations of version 1.5. Numerical simulations performed on this version include 2002 Hua-lien tsunami, 2003 Algerian tsunami, 2004 and 2005 Indian
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Ocean tsunamis and 2006 Java tsunami. For the 2004 Giant Tsunami, both runup and inundation were extensively studied in several regions. Gradually, more and more pressure was brought in therollout of a new version, which should be more stable, efficient, user-friendly and most of all, comprise all the features developed before. Finally, version 1.6 comes. In this version, a brand-new user interface is designed which requires only one parameter file, comcot.ctl, containing all the parameter setups for incident waves, fault models, landslide model and grid information. The grid hierarchy...