Sailing Across the Pacific

3,600 nautical miles. For some reason I love saying ‘nautical miles’. Anyway, 3,600 of the bastards lie between us and our destination, the Marquesas island chain on the eastern edge of French Polynesia. Soon, when the weather looks right, three of us are heading out to cover this not-immaterial distance in a 46′ sailboat. If we’re lucky and get good wind and favourable currents, we can probably make it in ~30 days of straight sailing, 24 hours per day, no land in sight.

Play time is over.

I’ve never made or planned a crossing like this before. Alan, the owner and skipper of Kia Ora, has thousands of nautical miles (‘nm’) under his belt, and has done numerous crossings, but never of the Pacific. The trip from the Americas across the Pacific is notable because it has nowhere to stop once you get into the trip towards the Marquesas. I’m not sure why I chose this as my first real sailing adventure – it’s probably due to a combination of stupidity and adventuretime – but I’m 90% excited and 10% scared.

Don’t get me wrong – I’m more than 10% ‘worried’, but the majority of concerns regarding the crossing can be addressed with adequate planning. Alan and Greg both have yachtmaster designations and are familiar with the extensive planning process involved in this type of expedition. I’m doing my best to catch up and have really enjoyed diving headfirst into it, especially the mapping part of course.

As I sit at the chart table and pour over nautical maps, guide books, websites and weather reports, I thought it might amuse a portion of you to get into the gritty details with me. The following is an extremely amateur guide to crossing the Pacific in a sailboat.

Maps

Have I mentioned I love maps? I’m pretty sure half the reason I love sailing so much is because it gives me an authentic excuse to surround myself with maps covered in little numbers. My favourite are the old-timey ones with topless mermaids of course, but those are less reliable than the ones prepared by the US Hydrographic Office, so we’ll stick primarily with the latter.

When it comes to nautical trip planning, there’s two main types of map (I’m sure there’s a billion more, but we’re at the 101 level here, so let’s just move along people) – Mercator projections and gnomonic charts. The difference comes down to how the Earth’s lines of latitude and longitude are represented, so let’s cover those briefly first.

Latitude measures how far above or below the equator a particular coordinate is. The lines of latitude run parallel to each other, horizontally across the planet. For example, at any given point on the planet, regardless of whether you’re near the equator or the poles, one degree of latitude equals almost exactly 60 nautical miles (69 ‘land’ miles or 111 kilometers). There is a small amount of variation given the elliptoid shape of the earth, but for sailing purposes the difference is negligible.

Longitude measures east-west distance around the world. Since there is no natural starting or ending point to this type of measurement, the British decided that they’d make Greenwich, UK, the centre of the nautical world and call that 0 degrees of longitude. The rest of the world didn’t really comply until the end of the 19th century. This is also why your clocks have a ‘GMT Offset’ when you set up a new computer or Playstation – Greenwich Mean Time is the temporal anchor for the world, give or take.

Unlike lines of latitude, lines of longitude (also called meridians) are not parallel, since they all run vertically up the curve of the earth and meet at the poles. As such, distances between the meridians aren’t equal – at the equator, one degree of longitude is the same as a degree of latitude (~60 nm) but as these lines approach the poles, the distance between them converges on zero.

Back to charts and trip-planning. Most people have heard the term ‘mercator projection’, usually for the first and last time in their grade 10 geography class. A mercator map uses strictly parallel lines of both latitude and longitude, dividing the globe into a massive grid. But since meridians are not parallel, this results in a stretching of distances the further away one measures from the equator.  Fuck you Greenland, you think you’re hot shit!?

Gnomonic charts, on the other hand, represent both the meridians and lines of latitude as curved, more accurately matching the surface shape of the earth. This is important when planning a long distance nautical voyage, because assuming you want to travel the shortest possible route to your destination, you need to take into account the curvature of the earth – a stright line on a mercator map will get you to your destination, but take you on a slightly roundabout route that can significantly increase the actual distance traveled (which sucks when you’re running out of water and have been reduced to eating canned tuna). This concept is generally referred to as ‘great circle distance.’

Now that I’ve somewhat boringly (it’s a word, shut up) explained all that, I can tell you that we don’t actually need to worry about any of these things because electronic GPS and automatic chart plotting take into account the great circle distance. But, as a sailor, it’s good to know these basics. Plus it gave me an excuse to look at a lot of maps.

The Trades

The trade winds, so named because they used to propel European traders around the globe, circulate in set patterns around six primary regions – each of the northern and southern zones of the Indian, Pacific and Atlantic oceans. Our launch-off point in southern Costa Rica puts us in a messy zone that lies somewhat outside the Pacific trade wind region. The wind here is not consistent, and is typically light and variable, which makes for bad sailing. To get into the trades, we’ve gotta head about 400 miles into the Pacific, which will get us away from the localized weather patterns in Central America, caused in part by how thin the land distance is here from the Caribbean (winds can run clear over the land mass and interact with prevailing Pacific systems).  The following image was generated here, a site which may actually be better than porn.

A lot depends on us finding the trades, because as mentioned, we have a long way to go and need to make regular progress. There is nowhere near enough diesel on board to get us to our destination, and there aren’t any convenient mid-way points to resupply. The 30 day estimate is based on making 5 knots per hour, every hour, 24 hours per day. The timeframe jumps to more than 50 days if we only average 3 knots.

Intertropical Convergence Zone

In between where the north and south Pacific trade winds meet is the Intertropical Convergence Zone (‘ITCZ’), a band of weather running around the world typically just north of the equator. It’s easy to picture this zone if you imagine the NE and SE trades as red and blue circles on the map that overlap a bit, near the equator – the purple swath running across the centre is the ITCZ. For science-y reasons, the ITCZ is wider in the eastern Pacific than it is through the central and western ocean. It’s typified by low pressure systems, inconsistent wind, thunderstorms and doldrums. Basically a shitty area to sail in.

The ITCZ moves around throughout the year, depending on the position of the sun and other, uh, stuff. It’ll be important that we check an updated weather map before we leave to see where the zone is currently resting. In late May – early June, Golfito lies a little bit within the northern edge of the eastern ITCZ, which sucks. Right now it looks like the ITCZ is a relatively thin band running from about 2°N to 8°N, right across the Pacific – directly in our path.

Severe Weather

There’s three kinds of storms that we theoretically might encounter on this route.

Depressions – these low pressure zones are associated with strong winds and rain, and can last up to four or five days. They’re predicted by a dropping barometer and a changing sky. They can be seen on radar and are usually avoidable if we keep up to date on weather news via Alan’s satellite phone or the single side-band radio.

Squalls – anyone who’s been to the Caribbean has seen one of these. They’re a pile of clouds with a flat bottom dumping a huge volume of rain, typically along with ample thunder and lightning, in a very localized area. You can see them from the beach with a slanty grey haze of rain underneath, while you sit there sipping margaritas in the sun. Since they’re so small and don’t cause any barometric response, they’re near impossible to predict. But if you don’t need the fresh water, they can be avoided or at worst endured for their two to four hour duration.

Tropical Revolving Storms – these are the end-boss badasses of the nautical storm world. Depending on where they’re found, you’ll have heard of them as hurricanes, cyclones or typhoons. They used to have fairly well established regions and seasons, but with global climate change, these have become less predictable. They can generate winds of up to 200 knots and the kind of waves that would knock over a low rise apartment. There’s strategies to surviving one if your boat is caught, but basically, the goal is to get the fuck out of the way.

Central America lies outside the hurricane danger zone. In addition, the hurricane season typically starts in June, so in theory, we’re safe. I’ve got huge brass balls, of course, but I’d rather not have to withstand one of these. I’ll just make sure I keep an ear on the weather reports…

Currents

Surface currents (the only ones we’re concerned with) in the oceans move in a similar pattern to the prevailing winds. They look like a big drain circling around the northern and southern halves of each ocean. Currents can be a significant aid or hindrance to our progress, since they can move from 1 – 3 knots per hour. With an over-surface boat speed of only say 5 knots, adding or subtracting 1 to 3 knots will make a big difference, so it’s important that we avoid opposing currents and find the good shit yo.

Near the equator, we’ll have to contend with three primary currents – the north equatorial counter current (which runs west to east at around 5°N), the south equatorial current (running east to west near 4°S) and the south equatorial counter current (running west to east at ~9°S). These regions are fluid (wah wah) so we can’t just plot a course and take a nap, but keeping the general directions in mind while we plan is key.

Our Sail Plan

The direct course from Golfito to the Marquesas is a heading of 252°, generally west south west (due west is 270°). While this would plot the shortest great circle distance between the points, it takes us through a lot of undesirable weather. First, it would keep us in this dead zone, formed by the huge gulf with Costa Rica on the north, Panama in the east and Colombia in the south, for an extended period of time. Second, we’d spend too much time fighting the north equatorial counter current as we diddled along north of the equator. Third, we’d be cutting a long, shallow path through the ITCZ, risking both doldrums and more severe, unpredictable weather, for longer than necessary.

As such, we’ve decided on an initial more southerly course, aiming generally to pass the Galapagos on the north – the primary goal is to get out of the dead zone in this gulf. We may be fighting against some localized currents pushing into the gulf, but that’ll be the lesser of various evils. Once we break free of the gulf, somewhere around 3°N, 90°W, we expect to pick up strong southerly winds which blow up and around the continental landmass at Ecuador. Here, we’ll adjust our heading westward.

Depending on the winds, we may stay north of the equator for a few hundred miles as far west as maybe 105°W. At this point, we’ll adjust our course due south to cut across the equator (and another dead zone that is either another ITCZ or simply a wind eddy trailing westward from the Galapagos), before picking up the steady SE trades. We can make a lot of westward distance sailing around 4°S, benefiting from both the winds and the southern equatorial current. We need to stay a bit north of the Marquesas’ latitude (~9°S) because of the counter current in that area.

Once we near the Marquesas, we’ll adjust our course southwards and cut down the last few degrees of latitude quickly. Our approach waypoint is 9°S 45′ 000, 138°W 45′ 000.

Then we get drunk as pirates.

Appendix I – The Galapagos

So, you ask, why aren’t we just going to the Galapagos as an early midway point, resupplying there, checking out some sea life, and then launching off again? Two reasons.

One, it’s fucking expensive and a bureaucratic nightmare – a cruiser recently reported total costs of stopping over in the Galapagos of US$5,000. Ecuador (who governs the Galapagos), have made it increasingly inhibitive to visit the islands. This is partially because Ecuador isn’t a rich country and they need the funds to maintain the environment of the region, but also partially related to our second reason.

Two, the Galapagos are over-visited. Tourism is literally destroying the environment that the tourists have gone to see. I’m no eco-warrior (I like peeing in the ocean off the side of the boat -weeee!) but it seems pretty fucking hypocritical to go somewhere to see some critters who will be incrementally killed by you looking at them. Like you’ve got laser eyeballs. Fuck you Cyclops, stay out of the Galapagos!

Anyway, reason one is a solid enough reason to avoid the islands if at all possible, so two is just icing. If something goes horribly wrong, we can always divert to the Galapagos and use them as an emergency waypoint. But nothing is going to go horribly wrong, so those little finches and cute baby turtles can live a few seconds longer because we’ve haven’t shown up with our laser eyeballs.