Offshore Sailing in the Climate Crisis – Part 1

Editor’s note: The author recently submitted this paper to the BCA Board of Directors for their consideration in anticipation of a strategic planning session in the fall. The BOD thought that sharing the paper would be of value to the membership and our Currents readership at large, hopefully stimulating some thoughtful conversation about the climate crisis and what we, as offshore sailors, need to think about.  

This is Part 1 of a two-part document outlining factors to be considered when preparing to sail offshore during the climate crisis. The time frame under consideration is 5 years. Many of the items listed are already in play in various parts of the world. This is a summary document, so it doesn’t provide references or descriptions of the driving mechanisms behind the changes. Basic information can be found in the reports issued by the Intergovernmental Panel on Climate Change. Given the inherent unpredictability of climate change, and ongoing research, the current status of the factors listed should be reviewed and updated frequently. There is also significant variation of these factors geographically.

Weather

Changes in global temperature and circulation patterns are leading to less stable weather. Extreme weather events will increase in both frequency and intensity in the coming months and years. Despite the increase in the amount of weather data available and the sophistication of forecast models, weather is becoming less predictable, especially over longer time frames.

Ongoing changes in the midlatitudes include:

• Wind
  • Increase in the average wind strength.
  • Increase in extreme storm frequency and intensity.
  • Increase in gust strength – especially associated with frontal systems.
  • Tropical storm (hurricane and cyclone) seasons are less well defined and becoming more active. The number of extra-seasonal tropical storms is increasing.
  • Tropical storms are occurring in locations where they have never occurred before.
  • Increase in the location and number of ‘calm zones’ at unusual times of year.
  • Increase in the frequency, intensity and duration of thunder and lightning storms.
  • Increase in the intensity and duration of rain storms (atmospheric rivers).
  • Increase in the strength of thermal winds – especially in areas close to high land temperatures.
• Waves
  • Overall increase in wave heights.
  • Increase in the variability and unpredictability of wave height.
  • Increase in the number and size of rogue waves.

• Generally, the same factors apply as in midlatitudes (excluding the tropical storm factors) however they will be more extreme.

Global Circulation

Research indicates that global circulation patterns are becoming unstable and may be close to tipping points. For example, the Gulf Stream (Atlantic meridional overturning circulation) appears to be weakening, more erratic in flow and more convoluted in direction. If it, or other major ocean circulation currents continue to weaken, shift dramatically or shut down, it will likely result in severe shifts in the weather that sailors encounter. There will be severe impacts on areas that benefit from either the importation of warm water, or the exportation of cold water. This could significantly change local wind and wave patterns, preferred sailing routes and the areas that are desirable as cruising grounds.

Sea Level Rise

Sea levels could rise significantly in the short-term depending on a number of factors – including ocean temperature increases and the melt rates of ice in Greenland and Antarctica (e.g. Thwaites Ice Shelf).

Ongoing changes include:

• Low lying island nations have, and will continue to, become less habitable and will likely not be open to cruising yachts.
• Increased wind, storm surge and sea level rise will lead to the destruction of coastal communities that are typically visited by cruising yachts.
• Sea level rise and storm surge will also make ports and marinas unusable without significant re-investment in infrastructure; consequently, marina space in some areas may be restricted or unavailable.

Navigation

Navigation and route planning will become more challenging as the climate crisis intensifies.

Ongoing changes are:

• Change in, and increased unpredictability of, the timing of safe passage on traditional sailing routes.
• Changes in storm tracks from the typical paths and the resultant narrowing of safe sailing route corridors.
• Silting of harbour entrances and bar crossings due to coastal erosion and extensive runoff will lead to harbour entrance routes being unpredictable after extreme weather events.
• Increasing sea level rise and storm surge will impact the safety of traditional anchorages.
• Rescue capability in response to EPIRBs may be less available as local coast guard resources are stretched or depleted by ongoing severe weather events.
• Preferred cruising areas will likely be very different in the future than they have been traditionally.
• Rapid and skillful navigational response to changing weather and harbour conditions will become more important.

Economics of Cruising

Ongoing changes are:

• Cost increases and decreased availability of fuel.
• Cost increases and decreased availability of moorage in marinas.
• Cost increases in insurance (both vessel and personal health) and increasing restrictions in the sailing areas where insurance is available.
• Significant cost increases of parts and cost of shipping parts to remote locations as supply chains and local infrastructure are impacted by the climate crisis.
• Cost increases in cruising permits, port and entrance fees, etc.
• Probable reduced availability of technicians skilled in maintenance and repair of boat systems since they will be required to focus on maintaining local infrastructure, or they will be much more expensive if they need to be flown in to conduct boat repairs.

The factors described above form the technical foundation of future cruising. As more climate research and model predictions become available, and the climate continues to change, it is important that new information is incorporated in voyage planning and preparation. Hopefully there will be ongoing discussions of this information in BCA meetings and Fleet Groups.

Part 2 of this article will explore how the climate crisis is influencing social factors in foreign countries and how that will impact cruising, emerging challenges in managing cruisers’ health when offshore, the psychology of sailing offshore in the climate crisis, ethical considerations and responsibilities, and keys to successful preparation.

Cover image: Author: kai Stachowiak, License: CC0 Public Domain

Stay tuned for Part 2 of this article, coming up in August.