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6.4.1 Hammer Projection (-Jh -JH)

The equal-area Hammer projection, first presented by Ernst von Hammer in 1892, is also known as Hammer-Aitoff (the Aitoff projection looks similar, but is not equal-area). The border is an ellipse, equator and central meridian are straight lines, while other parallels and meridians are complex curves. The projection is defined by selecting:

$\bullet$
The central meridian

$\bullet$
Scale along equator in inch/degree or 1:xxxxx (-Jh), or map width (-JH)

A view of the Pacific ocean using the Dateline as central meridian is accomplished thus





pscoast -Rg -JH180/4.5i -Bg30/g15 -Dc -A10000 -Gblack -P > GMT_hammer.ps





Figure 6.21: World map using the Hammer projection.
\includegraphics{eps/GMT_hammer}


next up previous contents index
Next: 6.4.2 Mollweide Projection (-Jw Up: 6.4 Miscellaneous Projections Previous: 6.4 Miscellaneous Projections   Contents   Index
Paul Wessel 2006-05-31