If one is not in the business of mapping long distance airplane and ship courses,it really is counter intuitive because we are used to using 2 dimensional maps-

which misrepresent a straight line or at least intuitively the shortest distance on the globe from Ensenada to Ningpo as being on a line from 31*N Ensenada to 29.8* N Ningpo-

without taking into consideration the spherical earth curvature- and I was of course using 2 dimensional maps to plot the coordinates-all nautical and terrestrial maps are 2 dimensional no matter how hard they try to compensate

E.g if a hiker wanted to hike from point A to point B but a very tall mountain (representing the earths spherical nature) exactly bisected the linear route,as long as the mountain wasnt extremely wide-it would be a shorter distance to partially walk around the mountain rather than climbing straight up to the peak on a 2 dimensional linear line

thats what the ships are doing in heading towards Alaska rather than climbing the very very high mountain of the earths curvature-as the circumference is greater as you approach the equator

maps would represent a straight linear ocean crossing between 2 points w similar latitudes as being along the ca 31* N latitude line-and from my quick reading of the def of a great circle as bisecting the center of the earth lat and long lines would qualify