SMSKN Tides & Currents Homework

January 17, 2024 Workshop

by Tom Bergh, Maine Island Kayak Co.

 

1.     Your review of today’s environmental conditions indicate that the winds will be 5 - 10 knots. The sea temperature is 52°F. The air temperature will be 54°F. The dew point is 53°F. The tide will be High around noon. What on-water conditions might you anticipate needing to deal with today, and how would you deal with them?

2.     You are staying at a friend’s home on the Northwest corner of Vineyard Haven Harbor on Martha’s Vineyard, and plan to paddle straight back to your mainland launch from Woods Hole, MA. You’ve figured out your course will be roughly North, 350 degrees Magnetic (M) directly to Woods Hole, MA. Which of the following swell forecasts would offer you a less challenging, likely safer crossing:

  • 4’ every 5 seconds; or
  • 1’ every 12 seconds?        

3.     You and your small group of 4 friends are on a sandy Maine pocket beach for a rest stop and snack break. You have a short 1+ nautical mile crossing from your island rest stop back to the put-in where your car is parked. This morning’s weather forecast referenced a cold front crossing your waters early afternoon today. It’s now 1330. High tide is at 1530. Your group of intermediate friends are ok paddlers and can paddle at a respectable 2-3 knots. From the approaching clouds on the horizon, you see and hear lightning and thunder, with the time between the flash and the thunder being 5-6 seconds apart. The clouds have a greenish tint to them. What should you consider doing to get back to your put-in this afternoon?

NDKs ready to launch

4.     Your small group of novice/lower intermediate friends have long wanted to circumnavigate Isle au Haut, either this or the following three-day weekend. You all have the time to camp out for a couple of nights, have heard that Wheat Island, just North of Isle au Haut is a beautiful spot, and all would like to try to circumnavigate IAH in a single day during your three day/two night-out weekend trip from Friday AM through Sunday PM.  This coming Saturday (This Weekend) Low Tide in Stonington will be around 0600. The weather conditions look favorable under an extended high pressure system for both of the possible weekends (This Weekend or Next Weekend), with the usual GOM Southwest winds ramping up into Force 3, each afternoon. 

  • Can your group paddle around IAH in one day IF you are reasonably comfortable that all paddlers will remain healthy although you are not all in equal physical condition? You will each have your usual safety equipment with you on the trip. 
  • Which weekend (This or Next) would you prefer for your circumnavigation?
  • Would you paddle clockwise or counter-clockwise?

5.     You and your small paddle group of four paddlers want to experience the surf wave that can develop on the sand bar that runs East/West between Pond and Wood Islands, just South of Fort Popham, located on the Kennebec River. You have heard that this wave develops best when the river’s maximum ebb current is flowing against, and thus stands up whatever swell may be rolling in from the South. 

Using the Currents Data for Hunniwell Point near the mouth of the Kennebec River, determine what day and what time your group should be on the beach at the NE corner of Wood Island an hour before the maximum ebb current, during the daylight hours, in June 2024. 

  • What do you figure the ebb current speed will be at that time?

6.     Please examine the following two images: one a US Geological Survey (USGS) topographical map, the other a NOAA Front Chart, and determine for yourself, the common graphical data feature shared and displayed on both types of maps. 

  • Do you see any similarity between a cone-shaped mountain (Mount Albion on the USGS map), and a high-pressure weather cell (marked H on the Front Chart)?
USGS Ward Quadrangle
NOAA Front Chart

“Wisdom is not a product of schooling but of the lifelong attempt to acquire it.”  Albert Einstein