function [pf,pu,t0,phase_mkB]=egbert_correc(mjd,hr,minute,second) %--------------------------------------------------------------------- % Correct phases and amplitudes for real time runs % Use parts of pos-processing code from Egbert's & Erofeeva's (OSU) % TPXO model. Their routines have been adapted from code by Richard Ray % (@?) and David Cartwright. %--------------------------------------------------------------------- % rad=pi/180.0; deg=180.0/pi; tstart=mjd+hr/24+minute/(60*24)+second/(60*60*24); disp(['Start date for nodal correction : ',mjd2greg(mjd)]); % % Determine nodal corrections pu & pf : % these expressions are valid for period 1990-2010 (Cartwright 1990). % reset time origin for astronomical arguments to 4th of May 1860: % timetemp=tstart-51544.4993; % % mean longitude of lunar perigee % ------------------------------- P = 83.3535 + 0.11140353 * timetemp; P = mod(P,360.0); P(P<0.0) = P(P<0.0) + 360.0; P=P*rad; % % mean longitude of ascending lunar node % -------------------------------------- N = 125.0445 - 0.05295377 * timetemp; N = mod(N,360.0) ; N(N<0.0) = N(N<0.0) + 360.0; N=N*rad; % % nodal corrections: pf = amplitude scaling factor [], % pu = phase correction [deg] sinn = sin(N); cosn = cos(N); sin2n = sin(2*N); cos2n = cos(2*N); sin3n = sin(3*N); tmp1 = 1.36*cos(P)+.267*cos((P-N)); tmp2 = 0.64*sin(P)+.135*sin((P-N)); temp1 = 1.-0.25*cos(2*P)-0.11*cos((2*P-N))-0.04*cosn ; temp2 = 0.25*sin(2*P)+0.11*sin((2*P-N))+0.04*sinn ; pftmp = sqrt((1.-.03731*cosn+.00052*cos2n)^2+ ... (.03731*sinn-.00052*sin2n)^2);% 2N2 pf( 1) = pftmp;% M2 pf( 2) = 1.0;% S2 pf( 3) = pftmp;% N2 pf( 4) = sqrt((1.+.2852*cosn+.0324*cos2n)^2+(.3108*sinn+.0324*sin2n)^2) ;% K2 pf( 5) = sqrt((1.+.1158*cosn-.0029*cos2n)^2+(.1554*sinn-.0029*sin2n)^2) ;% K1 pf( 6) = sqrt((1.+.189*cosn-0.0058*cos2n)^2+(.189*sinn -.0058*sin2n)^2) ;% O1 pf( 7) = 1.0;% P1 pf( 8) = sqrt((1.+.188*cosn)^2+(.188*sinn)^2);% Q1 pf( 9) = 1.043 + 0.414*cosn;% Mf pf(10) = 1.0 - 0.130*cosn ;% Mm putmp = atan((-.03731*sinn+.00052*sin2n)/ ... (1.-.03731*cosn+.00052*cos2n))*deg;% 2N2 pu( 1) = putmp;% M2 pu( 2) = 0.0;% S2 pu( 3) = putmp;% N2 pu( 4) = atan(-(.3108*sinn+.0324*sin2n)/(1.+.2852*cosn+.0324*cos2n))*deg;% K2 pu( 5) = atan((-.1554*sinn+.0029*sin2n)/(1.+.1158*cosn-.0029*cos2n))*deg;% K1 pu( 6) = 10.8*sinn - 1.3*sin2n + 0.2*sin3n;% O1 pu( 7) = 0.0;% P1 pu( 8) = atan(.189*sinn/(1.+.189*cosn))*deg;% Q1 pu( 9) = -23.7*sinn + 2.7*sin2n - 0.4*sin3n;% Mf pu(10) = 0.0;% Mm % to determine phase shifts below time should be in hours % relatively Jan 1 1992 (=48622mjd) t0=48622.0*24.0; % Astronomical arguments, obtained with Richard Ray's % "arguments" and "astrol", for Jan 1, 1992, 00:00 Greenwich time phase_mkB=[1.731557546,... % M2 0.000000000,... % S2 6.050721243,... % N2 3.487600001,... % K2 0.173003674,... % K1 1.558553872,... % O1 6.110181633,... % P1 5.877717569,... % Q1 1.756042456,... % Mf 1.964021610]*deg; % Mm