Friday, June 15, 2018

A Northern Sunrise

Back on May 26, when I flew from Washington, DC, to Geneva, Switzerland, the last rays of sunset lit the western horizon as we passed over Nova Scotia; by the time we reached Newfoundland, it was totally dark.  Within another hour, however, as we flew eastward above the North Atlantic, the glow of "sunrise" spread across the northern horizon and persisted until we angled southeastward toward the coast of Ireland; by then, the eastern sunrise had begun to illuminate the landscape.

That "northern sunrise" was, of course, the southern extent of the perpetual daylight that occurs above the Arctic Circle during the month preceding and the month following the summer solstice.  The tilt of the Earth's axis produces this annual phenomenon as well as the perpetual darkness surrounding the winter solstice.

As with most natural spectacles, it was a matter of being in the right place (i.e. latitude) at the right time.  Had we crossed the Atlantic farther south, I would not have seen the "northern sunrise."