Daily Update: Sharks and stormy seas
April 11, 2001
By Amy Nevala

Knorr’s lower lab received the alert just after breakfast.

“There is a shark off the bow, starboard side,” said geologist Susan Humphris, who has a sharp eye for spotting birds and fish. Her call sent us racing to the ship’s forward deck, arriving in time to see the shark’s cement-colored shadow swish near the surface, then fade into the sea foam.

Several people have spied the whitetip oceanic sharks swimming near Knorr, likely drawn to our food waste. The deep water species rarely goes close to shore and can grow up to 12 feet.

The sharks pose no danger to us, since we do not swim in these waters. When someone on Knorr spots a shark, it often draws a camera-carrying crowd eager for a look at these graceful, powerful creatures.

Today’s stormy seas were equally amazing to watch. With 15 to 18 foot waves rolling into Knorr, we careened down hallways and ladders, bumping shoulders into walls and straining to open the heavy doors when the tilting ship and gravity pulled them the opposite way. Today in the galley we ate off plates stuck to the tables with rubber mats and kept one hand on our sliding beverages.

Second Mate Doug Mayer said the winds and white-capped seas stem from a large, high pressure area to our south that is trying to fill the gaps of a small, low pressure area in the north. The meeting of these weather systems interrupts the constant Southeast Trade Winds of the Southern Hemisphere, which are blowing stronger than usual with winter descending on this half of the world.

Within 72 hours, Doug predicts that these squally conditions will diminish based on the weather reports we have received from South Africa, Réunion Island, the US Navy in Japan, and NOAA (National Oceanic and Atmospheric Administration) satellites.

Today’s weather made Jason’s delicate sampling at the vents impossible at our present location, so “rather than just sit around and twiddle our thumbs, we decided to go where we can do other research,” said geologist Dan Fornari.

Tonight we have a bumpy seven-hour, 85-nautical mile journey north to 24°00’S 69°40’E, our first research site. Nine days ago we left a current meter mooring in a spot where hydrothermal plumes were identified by previous expeditions and our initial tow-yo surveys.

Tomorrow we will release the current meter from its mooring. The data we gather will help us measure the speed and direction of ocean currents in this area of the Central Indian Ridge. This will help us to understand which direction the hydrothermal plumes drift, offering another clue to the vent’s location on the seafloor.

[Back to top]