Treacherous, frozen latitudes becoming hot destinations

Once upon a time, the ideal yachting expedition would involve calm seas, warm breezes and smooth sailing. The yachting season would follow the global circuit of chasing the sun and festivals, with promises of balmy nights and sun-soaked days. Now, however, extreme destinations are becoming a popular alternative for those who want their morning coffee served with a side of adrenaline. While the treacherous conditions may require the heartiest of captains and crew, the rewards of exciting adventure and exquisite landscapes are drawing many to the rugged ends of the Earth.

Some of the most obvious and immediate dangers of yachting through such high-latitude regions are the screaming winds and high seas associated with passing low pressure systems, but this does not discount other difficulties such as frigid temperatures, little or no available assistance in the event of emergency, drifting ice and thick, blinding fog.

When it comes to the volatile weather in the North polar regions, storm systems piggy back on the eastern-racing jet stream. When these systems reach the Eastern Seaboard and move offshore into the open Atlantic, they are often energized by the warm tropical waters hitchhiking along the Gulf Stream. These systems can often produce conditions in excess of 40-knot winds and 20-foot seas, with one storm after the next for months on end. The summer months are the best bet for lengthier breaks between storm systems, but no season is immune to nature’s fury. Taking into consideration a yacht’s top speed, maneuvering around the rapidly deteriorating sea state may prove to be challenging, and obtaining weather intelligence prior to departing is well-advised.

The infamous Northwest Passage, which connects the Atlantic Ocean to the Pacific Ocean via the Arctic waters around Greenland and through Canada, offers an alternative route that shaves off a considerable amount of time from the normal route.  With diminishing ice volume in the region, the waters have become more navigable, and were most recently crossed in 2016 by the cruise ship Crystal Serenity, which took 28 days.

Looking toward extreme destinations in the Southern Hemisphere, the subantarctic islands to the south of New Zealand and South America can be the destination or merely a stop along the way to the actual Antarctic continent itself. The conditions in this region of the world tend to remain hostile year-round. Minimal land mass in the Southern Hemisphere allows for storm systems to travel thousands of miles uninterrupted. With little to no frictional effects of land to slow these winds, storms are able to maintain their edge, giving way to the nicknames associated with their line of latitude, such as the “Roaring Forties,” “Furious Fifties,” and “Screaming Sixties.” Long-range swells associated with these winds make the higher latitude Southern Hemisphere seas very tumultuous.

Whether it’s the promise of isolation that draws the visitor, as the more common yachting circuit may yield congested harbors and ports, or the promise of nightly auroras and glowing, moonlit glaciers, extreme destinations are on the rise. Seafarer, beware – it is not for the faint of heart.

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Roll Clouds: The Most Unusual Cloud in the Skies

Turning towards the sky, one can’t help but become mesmerized by beauty and movement of the different clouds that flow across the atmosphere.  One of the most peculiar looking clouds, arcus clouds, are horizontal elongated tube-like clouds that can occur all over the world.  A subgenre of arcus clouds known as roll clouds, are even more atypical as they are detached from any other cloud features.

Roll-cloud
Roll cloud seen on January 25th 2009, on “Las Olas Beach”, located in “Punta del Este”, Uruguay, by Daniela Mirner Eberl.

While roll clouds can occur in many places, such as Germany, Canada, South Africa, Brazil, Uruguay, and even Florida, they are regionally known as “Morning Glory” clouds along the North Australian Coast, more specifically over the Cape York Peninsula and Gulf of Carpentaria.  The clouds are so named as a result of their early morning appearance, and frequently occur during late September and through early October in this region.  These phenomenal clouds may be on the order of 400-600 miles in length, ½ – 1 mile high, and may move as fast as 40 miles per hour.

As with any cloud, moisture must be present in order for water vapor to condense into water droplets.  Morning Glories tend to occur when humidity values are elevated and a clash of different air masses.  Once moisture levels are adequate, these clouds may form as a result of drastic temperature changes in air masses ahead of a thunderstorm, frontal boundary, or sea breeze.

MorningGloryCloudBurketownFromPlane
Morning glory cloud formation taken from a plane near Burketown (plane heading to Normanton) in QLD, Australia, 11 August 2009, by Mick Petroff

To understand the physical nature of a cloud, let’s first take a look at the relationship between air density and temperature.  Cold air is heavier than warm air as a result of more molecules per volume.

density

To better understand this, imagine a 10’ x 10’ unheated room in the middle of a Siberian winter.  For a person to keep warm, they would want to fill this room with as many other people as possible, capitalizing on generated body heat.  Now imagine that same 10’ x 10’ room located in the middle of hot Texas summer day with no available air conditioning.  In this scenario, a person may want to remove a majority of the heat generating bodies.  So if we exchange molecules for people in the above example, cold air has more molecules than warm air in the same amount of space, therefore making cold air denser (heavier) than warm air. This is what makes cold air sink downwards and warmer air upwards by nature.

A sudden influx of cold air can also force warm surface air to rapidly rise, which is often the case of what happens when cold air rushes out ahead of a thunderstorm or when sea breezes occur from differential daytime heating.  A gust front is the downward and outward rush of the colder/heavier air from within a thunderstorm, usually followed by strong winds, heavy rain, and possible hail within minutes.  An extremely strong gust front rush out faster, detaching from the parent storm, and creating a roll cloud.  Sea breeze circulations occur as the sun heats land and sea surfaces differently, creating an onshore flow during the day and offshore flow during the night hours.  When an extremely strong sea breeze occurs in the evening, the elevated chances of a Morning Glory cloud occurs the following morning.

While there’s no shortage of atmospheric phenomena to excite the average observer, it is without doubt that encountering a roll cloud is an incredible sight and definitely on any weather lover’s bucket list.

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This article was published in our monthly column within The Triton  newspaper (Nautical News for Captain and Crews), and can additionally be found here.