Which Way is the Wind Blowing

April-May 2001

This is an article from WaveLength Magazine, available in print in North America and globally on the web.
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by Graham Shuley

Long before the age of the magnetic compass, the Ancient Greeks considered direction and wind as synonymous. Those puffy-cheeked blowhards which symbolized the winds and adorned early maps and charts were much more than mere decoration-indeed, they were the main direction-markers used by serious navigators. Christopher Columbus' crew of able sailors thought of direction not as degrees of compass bearings but as los vientos, "the wind.". In those days practically all European sailors identified "direction" with the wind.

For millennia that mysterious energy which carried sailors across the sea was of course the subject of great interest. For any modern-day sea kayaker, whether novice or expert, wind still holds a power that can be awesome-in the true meaning of that worn-out word-and is considered by many experienced paddlers to be the single most potential hazard (besides outright foolhardiness). Other weather-related factors-rain, sun, cloud, fog-may pose challenges, but they don't hold a candle to the potential grief that can result from a strong bout of what Nero's teacher Lucius Annaeus Seneca (4 BC - AD 56) called "air flowing one way."

Not that wind always produces negative effects for paddlers. While paddling against the wind can be very difficult, travelling with the wind can result in a nice boost. The trick here is that your paddling direction will affect the apparent speed of the wind. For example, a 12-knot wind (a moderate breeze that can produce numerous white caps but is normally within the safety zone of almost any well-equipped, fit paddler) becomes 15 knots if you are paddling at three knots head into it. That same wind has an apparent speed of only nine knots if you are paddling three knots downwind. The difference of six knots in apparent wind can produce a noticeable difference in effort and even stability. This is especially true because the wind force is proportional to the square of the apparent wind speed. Thus, the favourable downwind push is only about 30 percent of the adverse upwind resistance. The long and short of it is that paddling into the wind can cause fatigue and make you wish you'd taken that extra few minutes to listen in on the marine weather forecast before launching.

There are several ways to become familiar with essential wind information, thereby reducing risk:

1. Obtain a marine weather forecast.

A Handheld Anemometer Photo by Laurie MacBride

You don't necessarily need a weatherman to know which way the wind blows, but it can sure help. Access to professional forecasts can be had via radio or television, over the Internet, with a special marine weather radio, or with a marine VHF radio. Listening to, and interpreting, marine weather forecasts takes practice. When using a radio, listen once while taking notes, then listen again to confirm what you heard the first time. Listen often, and note whether the forecast comes true or not (or to what extent the forecast is accurate). A professional marine weather forecast is essential to a paddler's safety, but keep in mind that the technology used to predict weather is by no means faultless.

2. Learn how to read the clouds and other signs for upcoming wind.

There are several good resources for this, but one of the very best ways to learn about clouds and their relationship to wind and weather is to keep a simple diary. Each evening before it gets dark, take note of cloud formations and wind direction. The next day, notice how the wind and weather conditions have changed. Do the same each morning, and observe subsequent conditions throughout the day. After keeping your diary for a few months, you will be very good at predicting how certain cloud formations lead to particular changes in the weather. And this knowledge may just save your bacon someday.

Very briefly, the four basic cloud types are: Cirrus appear very high in the sky and may foretell an approaching storm if they begin changing from whispy to more layered (but still high) cirrostratus or cirrocumulus. Stratus are low and gray, blanketing the sky, sometimes so low it is considered fog. Stratus can produce light rain or drizzle except when formed at higher levels, when precipitation is less likely. Nimbus produces bona fide rain, and sometimes heavy rain or thundershowers and hail. It is high-layered cloud that tends to increase in height ahead of a front (a line of separation between cold and warm air masses). Cumulus clouds often have that piled-up cotton candy look, with a flat base. Very high cumulus clouds may produce showers, otherwise they are often associated with fair, dry weather.

3. Get to know what wind velocities mean in terms of real-life conditions for you and your kayak on the water.

Before launching, listen in to your marine weather radio or VHF continuous forecast, dial the local weather station up, or log on to the Internet, and determine what the wind speed is for your area. Look carefully at the water conditions, especially wave action. Know that one knot of wind means one nautical mile per hour and is equal to about 1.8 kilometres per hour or about 1.2 statute miles per hour. While on the water, notice how certain wind speeds make you feel. Are you comfortable? Are you feeling pleasantly challenged? Do you wish you'd stayed home for that second cup of java? Do this a few times and you will know what it's like out there when you hear "small craft warning" or particular wind velocity predictions on the forecast.

Learn the basic terminology used by mariners: Light Air: 1-3 knots, very safe. Gentle Breeze: 7-10 knots, small whitecaps begin to appear, becoming challenging for kayakers. Moderate Breeze: 11-16 knots, upper limit for inexperienced paddlers. Fresh Breeze: 17-21 knots, quite challenging in a kayak, solid experience required. Strong Breeze: 22-27 knots, paddling is very difficult, be experienced, gear up for immersion, paddle with other experienced kayakers also dressed for immersion.

4. Learn about what sort of seasonal conditions tend to occur in your paddling location.

Are sudden squalls common during the winter months? Do high pressure systems tend to hang around in the summer? What is likely to occur in your area if the wind changes from north-easterly to southerly? Knowing the answers to these and other general questions about your area will help you assess the risk factor for heading out onto the water.

5. Know how wind interacts with other conditions on the water.

This is especially true for currents. Wind opposing currents will tend to steepen the waves, creating more hazardous conditions for paddlers and other small craft. Are you paddling in shallow water? Wind waves often steepen and break in shallow waters in such places as river mouths and tidal flats. Basic geographic knowledge is important because, for instance, it's important to know that wind will funnel and intensify through narrow channels, creating "gap winds" and thus increased potential hazards.
These are basic suggestions on how to become more acquainted with wind and weather-related conditions. As with any aspect of sea kayaking, accessing and interpreting wind and weather information takes practice. But it's the kind of information you need before launching.

Be thankful that you have relatively accurate marine weather forecasts at your disposal, and that you don't have to rely solely on ancient puffy-cheeked gods for your information on "air flowing one way".

Graham Shuley is a senior guide and instructor with Ocean River Sports in Victoria and holds BCU and SKGABC certificates. ©