The Winkel Tripel projection, presented by Oswald Winkel in 1921, is a modified azimuthal projection that is neither conformal nor equal-area. Central meridian and equator are straight lines; other parallels and meridians are curved. The projection is obtained by averaging the coordinates of the Equidistant Cylindrical and Aitoff (not Hammer-Aitoff) projections. The poles map into straight lines 0.4 times the length of equator. To use it you must enter
Centered on Greenwich, the example in Figure 6.23 was created by this command:
pscoast -Rd -JR0/4.5i -Bg30/g15 -Dc -A10000 -Ggray -P > GMT_winkel.ps