Mr. Tom's Blog

Green flash converts

It was in a cover photo from Scientific American that I first became aware of the Green Flash. If I remember right the picture was of a sunset somewhere in the Mediterranean. At the time I was living in Stockholm so the opportunities for seeing a green flash in person were poor at best. But the hope that I might someday see it never left me. But it would be another 20 years or so before I saw it for the first time, sitting at a hotel bar in Bermuda. I was so excited I put out a loud ‘wow, did you see that’! The others at the bar looked at me with a jaded ‘so what look’, I couldn’t interest them in what had just happened. Already then I was well aware that the green flash was considered ‘an old wife’s tale’. That was certainly the case some years later when a colleague joined me on an oceanographic cruise out of San Juan on the research vessel Gillis.

Our task was to deploy a current meter mooring to get a measure of eddy activity NE of Puerto Rico. At these latitudes the weather is mostly fair so the odds for seeing the green flash looked good. But being in the trade wind belt meant lumpy seas such that the Gillis rolled and pitched a lot. With the result that several members of our team were pretty much out of commission preferring to remain horizontal in their bunks. I think it might have been already that first evening when my student Scott McDowell and I were standing on the afterdeck of the Gillis hoping to see the green flash, and we did. Not only that, we saw it a second time as the stern area was lifted by a passing swell and the sun briefly reappeared. A bright emerald-green flash, no doubt the best one I’d ever seen, I was ecstatic. My colleague, who was not feeling well at all in these rolling seas, said I was mistaken, there is no such thing. He had a relative, an officer in the navy, who was well-aware of this question and had never the green flash in his many years of service at sea.

But my colleague was intrigued, no doubt by the fact that both Scott and I had claimed to have seen it. Being naturally curious, he ventured out of his bunk and came on deck the following evening to join the green flash watch. We were fortunate, again a beautiful flash. He wouldn’t admit that he saw it, but the way he said it hinted at something else. So, he joined us the next evening and again the green flash obliged. And this time he agreed, he saw it. In fact, he was so taken by what he had seen that he got the following morning before breakfast to see if he could catch it at sunrise, and he did. He became a green flash convert!

Many years later I was visiting my favorite city, Visby on the island of Gotland in the Baltic. Visby is medieval city with a mostly intact stone wall from the 1200s surrounding it, an impressive sight. My grandmother grew up in a merchant’s packhouse from the 1300s close to the old harbor. I had just arrived and true to habit went down to the old harbor just to hang out. It was a beautiful evening, and I became so convinced there would be a green flash that I got itchy, I couldn’t keep that knowledge to myself. Standing nearby was a group of elderly Germans, they seemed like they might receptive, so I approached them and told their leader in English what was going to happen. He told the group, and in their murmurs I could hear considerable skepticism – ‘ach, das ist nur ein Märchen’ or words to that effect. So I told them what to expect, that at the very last moment before the upper rim of the sun finally disappears below the horizon, it will for a brief instant turn green and with luck flash a bright green. I also instructed them not to stare at the sun but wait until the last moment, I would tell them when to look. To pass the time while waiting we talked about this and that. They were an elder hostel group, roughly 10 men and women traveling around Sweden, now visiting Visby. I told them I had just arrived from Stockholm where earlier in the day I had witnessed Sweden’s brand new jet fighter plane, Gripen, flame out in an air show over the city and crash only meters away from a bridge full of spectators; it was a miracle that no one was killed.

The moment finally arrived for the green flash and I told them they could look at the sun reminding them what was going to happen just before it disappears. It was a calm evening with not a breeze, so the sea was glassy flat and the horizon was sharp. Just before the last of the sun disappeared, she sent out the most glorious beam of green light, it was a ‘wow’! I was impressed, and so was everyone in the group, they all saw it and became instant converts. They started to look at me as if I were some kind of a seer. Moments like that make your day!