GP15 by the numbers

Days at sea: 67

All 37 members of GP15’s leg 1 science party stand together before arriving in Hilo, Hawaii.

The science party of GP15’s second leg.

People on board: 59 (37 science party; 22 crew)

Stops between Seattle, WA (departed 9/18/18) and Papeete, Tahiti (arrived 11/25/18):

1 (Hilo, Hawaii 10/21/18-10/25/18)

Stations sampled: 36

Largest waves: ~15-foot swell near Alaska

Flying fish landed on deck: Countless

Sharks sightings: ~6

Dolphin sightings: 1

Whale sightings: 0 (unless nobody told me)

Holidays at sea: 2

Midterm elections at sea: 1

Toaster repairs: 3

Internet data usage: 450 gigabytes

Liters of seawater filtered by the pumps sampling system: 491,819

Seawater collected by the non-trace metal CTD rosette: 34,200 liters

Seawater collected by the trace metal CTD rosette: 20,736 liters

Volume of air sampled for aerosol trace elements: 315,882 cubic meters

Nutrient measurements performed on board: 21,712

From trace metal CTD rosette Super Techs Laramie Jensen and Brent Summers:

• Sample bottles filled: 15,758
• GoFlo bottles racked inside lab van: 1,700
• Bottle rinses: 47,274
• Longest work day: 39 hours
• GoFlo bottles lost to sea: 1  (RIP #45);
• Pallets filled with seawater samples: 12.5

A selection of mechanical issues encountered at sea:

• The trace metal CTD rosette’s electrical connection to the ship via its cable failed. Learn more.
• During the rough weather encountered in the northern portion of the expedition, the surface sampling system, called the fish, had considerable problems.
  • The fish’s torpedo is designed to keep it submerged and away from the ship, but in big swell it began breaching. This required numerous adjustments of its fin angles and countless hours of nervous observation.
• During station 11, the motor on the A-frame, used to angle the trace metal CTD rosette into the sea, seized up.
  • The ship’s electrician Harry Smith rebuilt the motor, which worked well for the rest of the expedition.

• At Station 16, a winch operator error damaged the cable used to lower the pump sampling system. The cable was so damaged it wasn’t clear it could hold the pumps without breaking.
  • After many hours applying temporary repairs (Scotch coat and electrical tape), pump operations resumed for the next 2 stations.
  • During GP15’s port stop in Hilo, Hawaii, the team cut off the thousands of feet of damaged cable.
  • Co-chief Scientist Phoebe Lam arranged for a replacement cable to be flown in from UC Santa Cruz.
  • A technician from Cortland Cable, the manufacturer, flew in to splice on a ~12,000-foot section of new cable to the remaining ~10,000 feet of undamaged cable.

You can find an archive of blog posts created during this expedition here.

Blog posts created or edited by Alex Fox.

Follow GEOTRACES GP15 on WordPress.com

Funding for this research is provided by NSF Chemical Oceanography.

GEOTRACES GP15 is supported by the National Science Foundation. Any opinions, findings and conclusions or recommendations expressed in this material do not necessarily reflect the views of the National Science Foundation.