Back in Minnesota, rainbows are a rare treat. They’re enchanting, surprising, here and gone in a flash. So, imagine how delightful it’s been to witness an extraordinary wealth of rainbows while cruising the South Pacific on Wanderlust.
The Science (with a Tropical Twist)
Out here, the recipe for rainbows seems almost guaranteed. A cumulonimbus cloud blows through and gives us an uninvited sprinkle or unexpected quick dousing. It’s just enough to prompt a ‘hatch dance,’ the scramble to button things up. Then the sun breaks out in its passing, and suddenly – somewhere - the sky is alive with color…at the horizon, up in the clouds or over the island.
Science explains it this way: clear, tropical air holds just the right amount of moisture, while the ocean or lagoon acts like a vast reflector. Especially when the sun is low on the horizon, the angles are perfect for light to bend and scatter through countless water droplets—each one a tiny prism—until a full arc blooms across the sky. ROY G. BIV*, indeed.
Knowing the how’s and why’s isn’t a distraction; it’s the exclamation point on the rainbow’s fleeting beauty.
Omens? Good Luck Charms? or perhaps, just a bit of the unexpected.
Some of my favorite rainbows appeared when I least expected them. Our day of departure from Marsden Cove Marina (New Zealand) dawned overcast and rainy, dampening our spirits as well as the boat. Closing in on our time to depart, the sun broke through and a double(!) rainbow arched across the channel leading out to sea. Coincidence? Maybe. No matter, it bolstered our excitement as we left the marina behind us.
Heading from Tahiti to the Tuamotus with a couple night watches under our belts and the remnants of a shower behind us, we spotted Rangiroa on the horizon. A rainbow burst across the atoll, as if to bid us welcome.
At anchor in the lagoon, Wanderlust rolls in tune with current and the Trade Winds, and we watch the puffy dark clouds as we swing under them. A quick cloud burst or a quiet sprinkle plus a pop of sunshine, and there it sits – a brief, small swatch of intense color up in the clouds.
The Magic
Sometimes, as it did in Mo’orea, the arch falls to the ground against the lush green of the island, its golden shimmer tempting you to believe, if only for a second, that maybe the old legends weren’t entirely wrong.
It’s simple science—sunlight bending through countless droplets—but here it feels like more. Each rainbow is a reminder of why we came: to slow down, to notice, to be wowed.
*For the uninitiated: Red Orange Yellow Green Blue Indigo Violet (ROY G. BIV)