Tuesday 03 February, 2004

This morning I awoke to feel the ship rocking more than it has in the past week. The sky is gray with clouds, and there has been rain. The small boat operation was cancelled for today due to the swell and some complications with the small CTD (see field equipment) that they take out in the boat.

Tides
Chirping continued this morning, and we reached an "anchor station" today at 1300. An anchor station is a location selected by the researchers where samples will are collected throughout a full day. This location has been visited during different seasons and during different tidal ranges. A tidal range is the difference in vertical elevation between high and low tide, and at the mouth of the Fly River, it averages about 3 meters (10 feet). We are currently experiencing a spring tide that occurs approximately every 14-15 days at the time of a full moon or a new moon. The gravitational pull between the sun, moon and earth is greater at this time and the result is a larger tidal range. A week ago, when the moon was half full, we were at this same site collecting data during the neap tide. A neap tide occurs every 14-15 days during half moon phases. They typically have a smaller tidal range. Today´s lecture was given by Chuck Nittrouer from University of Washington. He taught us about tides and explained the reasons and benefits of conducting anchor stations.

Anchor Stations
During an anchor station, water samples and water-column data, such as salinity and temperature, are collected using the BLISP and CTD, and sediment samples are collected using the box core. Every hour, for 24 hours, Andrea Ogston and Cathy Presto take a BLISP profile and water samples. Every two hours, a CTD profile is conducted as well by Miguel Goni and Natalie Monacci to obtain large volume water samples, and Chuck Nittrouer and John Crockett use the box core to look at seafloor changes every two hours as well. One-third of the sediment samples extracted from the box core are given to Miguel and Natalie to compare with water-column observations.

They are looking at the carbon content in the water and seabed to understand how it moves from land into the ocean. By improving knowledge on carbon dynamics, they may be able to help understand past and present climate change and assist in finding oil. For example, they work to determine if carbon is consumed by bacteria and returned to the atmosphere as carbon dioxide, a greenhouse gas, or if it is buried in the seafloor and, thus, removed from the atmosphere permanently. This is important to understanding both the past and future of our earth.

Weather (Today's weather and location at 0900)

Air Temperature: 27.05°C (80.69°F)
Water Temperature: 30.01°C (86.02°F)
Salinity: 33.61
Barometric Pressure: 1007.55 cmbar
Precipitation: 31.5 mm (last 24 hours)

Location
Longitude: 8° 48.537' S
Latitude: 144° 05.609' E

Menu
Breakfast: Bacon, ham, eggs, potatoes, fresh fruit, blueberry pancakes, and coffee cake
Lunch: Chicken pot-pies, spicy Creole shrimp and rice
Dinner: Lamb shanks or steak Darien
Dessert: Carrot Cake