!********************************************************************** ! Copyright 1998,1999,2000,2001,2002,2005,2007,2008,2009,2010 * ! Andreas Stohl, Petra Seibert, A. Frank, Gerhard Wotawa, * ! Caroline Forster, Sabine Eckhardt, John Burkhart, Harald Sodemann * ! * ! This file is part of FLEXPART. * ! * ! FLEXPART is free software: you can redistribute it and/or modify * ! it under the terms of the GNU General Public License as published by* ! the Free Software Foundation, either version 3 of the License, or * ! (at your option) any later version. * ! * ! FLEXPART is distributed in the hope that it will be useful, * ! but WITHOUT ANY WARRANTY; without even the implied warranty of * ! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * ! GNU General Public License for more details. * ! * ! You should have received a copy of the GNU General Public License * ! along with FLEXPART. If not, see . * !********************************************************************** real function scalev(ps,t,td,stress) !******************************************************************** ! * ! Author: G. WOTAWA * ! Date: 1994-06-27 * ! Update: 1996-05-21 A. Stohl * ! * !******************************************************************** ! * ! This Programm calculates scale velocity ustar from surface * ! stress and air density. * ! * !******************************************************************** ! * ! INPUT: * ! * ! ps surface pressure [Pa] * ! t surface temperature [K] * ! td surface dew point [K] * ! stress surface stress [N/m2] * ! * !******************************************************************** use par_mod implicit none real :: ps,t,td,e,ew,tv,rhoa,stress e=ew(td) ! vapor pressure tv=t*(1.+0.378*e/ps) ! virtual temperature rhoa=ps/(r_air*tv) ! air density scalev=sqrt(abs(stress)/rhoa) end function scalev