C **** fieldz.h.1 C **** /FIELD/ CONTAINS MAGNETIC QUANTITIES READ FROM MASS STORE fieldz.h.2 C **** fieldz.h.3 COMMON/FIELD/ALATM(IMAXGP,0:JMAXGP),ALONM(IMAXGP,0:JMAXGP), fieldz.h.4 1 XB(IMAXGP,0:JMAXGP),YB(IMAXGP,0:JMAXGP),ZZB(IMAXGP,0:JMAXGP), fieldz.h.5 2 BMOD(IMAXGP,0:JMAXGP), fieldz.h.6 3 RJAC(IMAXGP,0:JMAXGP,2,2),AV(IMAXGP,0:JMAXGP,3,2) fieldz.h.7 C **** fieldz.h.11 C **** WHERE: fieldz.h.12 C **** ZIMX=72, ZJMX=36, ZIMXP1=ZIMX+1, ZJMXP1=ZJMX+1 fieldz.h.13 C **** ALATM = GEOMAGNETIC LATITUDE AT EACH GEOGRAPHIC GRID fieldz.h.14 C **** POINT (RADIANS) fieldz.h.15 C **** ALONM = GEOMAGNETIC LONGITUDE AT EACH GEOGRAPHIC fieldz.h.16 C **** GRID POINT (RADIANS) fieldz.h.17 C **** XB = NORTHWARD COMPONENT OF MAGNETIC FIELD fieldz.h.18 C **** YB = EASTWARD COMPONENT OF MAGNETIC FIELD fieldz.h.19 C **** ZB = DOWNWARD COMPONENT OF MAGNETIC FIELD fieldz.h.20 C **** BMOD = MAGNITUDE OF MAGNETIC FIELD (IN GAUSS?) fieldz.h.21 C **** DMLAT = DIPOLE LATITUDE CORRESPONDING TO APEX OF fieldz.h.22 C **** FIELD LINE fieldz.h.23 C **** RJAC(2,2) = SCALED DERIVATIVES OF GEOMAGNETIC fieldz.h.24 C **** COORDINATES W.R.T. GEOGRAPHIC COORDINATES fieldz.h.25 C **** RJAC(1,1) = COS(THETAS)/COS(THETA)*D(LAMDAS)/D(LAMDA) fieldz.h.26 C **** RJAC(1,2) = COS(THETAS)*D(LAMDAS)/D(THETA) fieldz.h.27 C **** RJAC(2,1) = 1./COS(THETA)*D(THETAS)/D(LAMDA) fieldz.h.28 C **** RJAC(2,2) = D(THETAS)/D(THETA) fieldz.h.29 C **** fieldz.h.30 C **** WHERE (LAMDA,THETA) ARE GEOGRAPHIC COORDINATES fieldz.h.31 C **** (LAMDAS,THETAS) ARE GEOMAGNETIC COORDINATES fieldz.h.32 C **** RJACD = DETERMINANT OF RJAC fieldz.h.33 C **** AV = THE TWO MAGNETIC VECTORS A1 AND A2 fieldz.h.34 C **** AV1 = A1 fieldz.h.35 C **** AV2 = A2/COS(THETAS) fieldz.h.36 C **** P = SCALE FACTOR BETWEEN GEOGRAPHIC AND GEOMAGNETIC fieldz.h.37 C **** SYSTEMS DIVIDED BY SIN(DIP)*COS(THETAS) fieldz.h.38 C **** = RS**2*COS(THETA)/(BMOD*COS(THETAS))* fieldz.h.39 C **** D(LAMDA,THETA)/D(LAMDAS,THETAS)) fieldz.h.40