ITCZ

The singular geographical landmark in our route from Ensenada to the Marquesas was Isla Guadalupe, and we passed it a day and half after leaving Mexico. Since then, we’ve been using meteorological landmarks, conditions of the wind and ocean, to navigate the seas. First we were in the northerly trades off the coast, and then we road the northeasterly trades like a highway into the Pacific. We’re currently experiencing one of the more prominent meteorological trends of note, the ITCZ.

‘ITCZ’ stands for ‘intertropical convergence zone’ and defines the area where the clockwise weather patterns of the northern hemisphere collide with the counterclockwise patterns of the southern hemisphere. This collision creates a weather band of varying width that can shift between zero and ten degrees latitude in just a few days. Fueled by warm waters—we’re up to 84 degrees—and converging winds, conditions in the ITCZ are notoriously flukey and unpredictable, alternating between doldrums and squalls: discrete yet intense storms with high drama vertical clouds, heavy wind, tropical rain, and occasional lightning.

Thankfully, we haven’t seen lightning yet, and the intermittent showers of the last 24 hours have been a welcome reprieve from the powerful tropical sun. The clouds keep our skin from burning and our selves from sweltering; the showers wash two weeks worth of crusted salt and kamikaze fish detritus from the deck. I’m also happy to report that Helios has been a safe haven for a variety of animals in the storms. A squid sought refuge and jumped out of the ocean and into our cockpit; a very lost laughing gull spent about thirty minutes sliding around the deck, her webbed feet unable to perch securely on any of our rigging.

Because conditions are so variable (we’ve heard of people waiting 20 minutes for the south eastern trades, we’ve heard of people waiting for ten days), we’ve been alternating between sailing and motoring. Sailing when winds permit speed and comfort in a southerly direction, motoring to hit the southeasterlies as soon as possible. It’s tricky to plan for because a sailing vessel crosses the ITCZ about two weeks after departing North America, and two weeks is too far into the future to really get an accurate weather prediction. As we’ve approached the ITCZ we’ve been tracking its location. The band is narrow and northerly, around seven degrees latitude. It appears to be getting smaller and moving farther north, and we seem to have passed the measure pressure depression therein. Sadly, the south eastern trades still seem a day or two away, so we may be motoring more than we’d like until we feel the sails fill once again.

In the meantime, the equator is a mere 350 miles away, and we’ve begun planning our equator crossing celebration. I’m seeing something bacchanal, something with champagne, togas, and a saltwater baptism for the crew.