... 1988^1.1

Version 1.0 was then informally released at the Lamont-Doherty Earth Observatory.

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...clock^1.2

Use standard UNIX tools such as awk or perl to reformat files should your date and clock components reside in separate columns.

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... colors^1.3

Used to color the background, foreground, and Not-a-Number areas.

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... free^2.1

See GNU General Public Licence (www.gnu.org/copyleft/gpl.html) for terms on redistribution and modifications.

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... tools^2.2

The tools can also be installed on other platforms (see Appendix L).

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... writers^2.3

One public-domain RIP is ghostscript, available from www.gnu.org.

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... column^2.4

Programs now also allow for fast, binary multicolumn file i/o.

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... another^2.5

While the netCDF format is the default, other formats are also possible, including user-defined formats.

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... inch)^4.1

PostScript definition. In the typesetting industry a slighly different definition of point (1/72.27 inch) is used.

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... defaults^4.2

Choose between SI and US default units by modifying gmt.conf in the GMT share directory.

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... directory^4.3

To remain backwards compatible with GMT 3.4.x we will also look for .gmtdefaults but only if .gmtdefaults4 cannot be found.

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... reforms^4.4

The Gregorian Calendar is a revision of the Julian Calendar which was instituted in a papal bull by Pope Gregory XIII in 1582. The reason for the calendar change was to correct for drift in the dates of signifigant religious observations (primarily Easter) and to prevent further drift in the dates. The important effects of the change were (a) Drop 10 days from October 1582 to realign the Vernal Equinox with 21 March, (b) change leap year selection so that not all years ending in "00" are leap years, and (c) change the beginning of the year to 1 January from 25 March. Adoption of the new calendar was essentially immediate within Catholic countries. In the Protestant countries, where papal authority was neither recognized not appreciated, adoption came more slowly. England finally adopted the new calendar in 1752, with eleven days removed from September. The additional day came because the old and new calendars disagreed on whether 1700 was a leap year, so the Julian calendar had to be adjusted by one more day.

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... coordinates.^4.5

While UTM coordinates clearly refer to points on the Earth, in this context they are considered ``other''. Thus, when we refer to ``geographical'' coordinates herein we imply longitude, latitude.

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... plot^4.6

However, it is suppressed when a 3-D view is selected.

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... numbers^4.7

Please consult the man page for printf or any book on C.

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... mode^4.8

For historical reasons, the GMT Default is Landscape, see gmtdefaults to change this.

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... plots^4.9

Ensures that boundary annotations do not fall off the page.

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... 0-1^4.10

For an overview of color systems such as HSV, see Appendix I.

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... table^4.11

On most UNIX-type systems you can find the file rgb.txt in /usr/X11R6/lib/X11 or thereabouts, or use the command showrgb.

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... rasterfiles^4.12

Convert other graphics formats to Sun ras format using ImageMagick's convert program.

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... system^4.13

For CMYK the format obviously involves two extra columns.

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... [1987]^6.1

Snyder, J. P., 1987, Map Projections A Working Manual, U.S. Geological Survey Prof. Paper 1395.

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... voyage^6.2

This is, however, not the shortest distance. It is given by the great circle connecting the two points.

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... right^6.3

Robinson provided a table of $y$-coordinates for latitudes every 5$^{o}$. To project values for intermediate latitudes one must interpolate the table. Different interpolants may result in slightly different maps. GMT uses the interpolant selected by the parameter INTERPOLANT in the .gmtdefaults4 file.

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... bathymetry^7.1

These data are available on CD-ROM from NGDC (www.ngdc.noaa.gov).

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... maps^7.2

These data are available on CD-ROM from NGDC (www.ngdc.noaa.gov).

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... field^7.3

See http://topex.ucsd.edu/marine_grav/mar_grav.html.

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... URL^7.4

You can also use the utility curl

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... arrival^7.5

Pedants who wish to argue about the ``other'' arc going the long way should consider using it.

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... Cox^A.1

Simon.Cox@csiro.au

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... altimetry^A.2

For data bases, see http://topex.ucsd.edu/marine_grav/mar_grav.html.

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... Smith^A.3

walter@raptor.grdl.noaa.gov

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... Feigl^A.4

Kurt.Feigl@cnes.fr

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... Patau^A.5

patau@ipgp.jussieu.fr

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... formats^A.6

The ASCII MGD77 data are available on CD-ROM from NGDC (www.ngdc.noaa.gov).

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... format^A.7

These data are available on CD-ROM from NGDC (www.ngdc.noaa.gov).

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... Henstock^A.8

Timothy.J.Henstock@soc.soton.ac.uk

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... Parkes^A.9

lloyd@must-have-coffee.gen.nz

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... plot^C.1

In contrast, regular GMT PostScript files simply have a %%BoundingBox that equal the size of the chosen paper.

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... GNU^D.1

www.gnu.org

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... RedHat^D.2

http://sources.redhat.com/bzip2/index.html

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... available^D.3

Required with GMT_exe.zip

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... file^F.1

If you chose SI units during the installation then the default encoding is ISOLatin1+, otherwise it is Standard+.

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... printers^H.1

Note, however, that the -Q option in grdimage will exercise a PostScript Level 3 feature called colormasking.

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... Bracewell^J.1

R. Bracewell, The Fourier Transform and its Applications, McGraw-Hill, London, 444p., 1965.

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... Colorado^K.1

www.ngdc.noaa.gov

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... algorithm^K.2

Dougles, D.H., and T. K. Peucker, 1973, Algorithms for the reduction of the number of points required to represent a digitized line or its caricature, Canadian Cartographer, 10, 112-122.

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... option^K.3

The full and high resolution files are in separate archives because of their size. Not all users may need these files as the intermediate data set is better than the data provided with version 2.1.4.

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... platforms^K.4

If you need complete polygons in a simpler format, see the article on GSHHS (Wessel, P., and W. H. F. Smith, 1996, A Global, self-consistent, hierarchical, high-resolution shoreline database, J. Geophys. Res. 101, 8741-8743).

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... Microsoft^L.1

Microsoft Services for UNIX is formerly known as Interix, in the distant past known as OpenNT.

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... MachTen^L.2

www.tenon.com

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... page^L.3

sources.redhat.com/cygwin

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...SFU^L.4

See www.microsoft.com/Windows/sfu for details.

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...DJGPP^L.5

See www.gnu.org for details.

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... Earth^O.1

or whatever planet we are dealing with.

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... Islands^O.2

Travel times were calculated using Geoware's travel time calculator, ttt.

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