NAME

       pssolar - Plot day-light terminators and other sunlight parameters

SYNOPSIS

       pssolar  [   -B[p|s]parameters  ]  [   -C ] [  -Gfill|c ] [  -I[lon/lat][+ddate][+zTZ] ] [
       -Jparameters ] [  -K ] [  -M ] [  -N ]  [   -O  ]  [  -P  ]  [   -Q  ]  [   -Rregion  ]  [
       -Tdcna[+ddate][+zTZ]]  [   -U[stamp]  ]  [   -V[level]  ]  [   -Wpen  ]  [  -Xx_offset ] [
       -Yy_offset ] [ -bobinary ] [ -hheaders ] [ -oflags ] [ -pflags ] [ -ttransp ]

       Note: No space is allowed between the option flag and the associated arguments.

DESCRIPTION

       pssolar  Calculate  and  plot  the  day-night  terminator  and  the  civil,  nautical  and
       astronomical twilights.

REQUIRED ARGUMENTS

       There are no required arguments but either -I or -T must be selected.

OPTIONAL ARGUMENTS

       -B[p|s]parameters (more ...)
              Set map boundary frame and axes attributes.

       -C     Formats  the report selected by -I using tab-separated fields on a single line. The
              output is Sun Lon Lat Azimuth Elevation in degrees, Sunrise Sunset Noon in  decimal
              days,  day  length  in minutes, SolarElevationCorrected corrected for the effect of
              refraction index and Equation of time in minutes.  Note  that  if  no  position  is
              provided in -Ilon/lat the data after Elevation refers to the point (0,0).

       -Gfill|c
              Select  color  or  pattern  for  filling  of  terminators;  or use -Gc for clipping
              [Default is no fill].  Deactivate clipping by appending the output  of  gmt  psclip
              -C.

       -I[lon/lat][+ddate][+zTZ]
              Print  current  sun  position  as  well as Azimuth and Elevation. Append lon/lat to
              print also the times of Sunrise, Sunset, Noon and length of the day.  Add +ddate in
              ISO  format,  e.g,  +d2000-04-25,  to  compute  sun  parameters  for  this date. If
              necessary, append time zone via +zTZ.

       -Jparameters (more ...)
              Select map projection.

       -K (more ...)
              Do not finalize the PostScript plot.

       -M     Write terminator(s) as a multisegment ASCII (or binary, see -bo) file  to  standard
              output. No plotting occurs.

       -N     Invert  the  sense  of  what  is inside and outside the terminator.  Only used with
              clipping (-Gc) and cannot be used together with -B.

       -O (more ...)
              Append to existing PostScript plot.

       -P (more ...)
              Select "Portrait" plot orientation.

       -Rxmin/xmax/ymin/ymax[+r][+uunit] (more ...)
              Specify the region of interest.

       -Tdcna[+ddate][+zTZ]
              Plot (or dump; see -M) one or more terminators defined via the dcna flags. Where: d
              means  day/night  terminator;  c means civil twilight; n means nautical twilight; a
              means astronomical twilight.  Add +ddate in ISO format, e.g,  +d2000-04-25T12:15:00
              to  know  where  the day-night was at that date. If necessary, append time zone via
              +zTZ.

       -U[[just]/dx/dy/][c|label] (more ...)
              Draw GMT time stamp logo on plot.

       -V[level] (more ...)
              Select verbosity level [c].

       -W[-|+][pen] (more ...)
              Set pen attributes for lines or the outline of symbols [Defaults: width =  default,
              color = black, style = solid].

       -X[a|c|f|r][x-shift[u]]

       -Y[a|c|f|r][y-shift[u]] (more ...)
              Shift plot origin.

       -bo[ncols][type] (more ...)
              Select native binary output.

       -h[i|o][n][+c][+d][+rremark][+rtitle] (more ...)
              Skip or produce header record(s).

       -ocols[,...] (more ...)
              Select output columns (0 is first column).

       -p[x|y|z]azim[/elev[/zlevel]][+wlon0/lat0[/z0]][+vx0/y0] (more ...)
              Select perspective view.

       -t[transp] (more ...)
              Set PDF transparency level in percent.

EXAMPLES

       Print current Sun position and Sunrise, Sunset times at:

              gmt pssolar -I-7.93/37.079+d2016-02-04T10:01:00

       Plot the day-night and civil twilight

              gmt pscoast -Rd -W0.1p -JQ0/14c -Ba -BWSen -Dl -A1000 -P -K > terminator.ps

              gmt pssolar -R -J -W1p -Tdc -O >> terminator.ps

       Set up a clip path overlay based on the day/night terminator:

              gmt pssolar -R -J -Gc -Tc -O -K >> someplot.ps

SEE ALSO

       gmt, psclip, pscoast, psxy

COPYRIGHT

       2019, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe