NOAA Teacher at Sea
Debra Brice
Onboard R/V Roger Revelle
November 11-25, 2003
Mission: Ocean Observation
Geographical Area: Chilean Coast
Date: November 12, 2003
Data from the Bridge
1. 111700Z Nov 03
2. Position: LAT: 01-55.6S, LONG: 083-46.1W
3. Course: 251-T
4. Speed: 13.9 Kts
5. Distance: 193.6 NM
6. Steaming Time: 13H 54M
7. Station Time: 00H 00M
8. Fuel: 2951 GAL
9. Sky: OvrCst
10. Wind: 200-T, 11 Kts
11. Sea: 200-T, 2-3 Ft
12. Swell: 200-T, 3-5 Ft
13. Barometer: 1011.2 mb
14. Temperature: Air: 24.2 C, Sea 23.3 C
15. Equipment Status: NORMAL
16. Comments: Enroute to Stratus buoy site.
Science and Technology Log
Today is a travel day and we are on route to the site of the Stratus Buoy maintained by Woods Hole Oceanographic Institution. The Chief Scientist for this cruise is Dr. Robert Weller, a Physical Oceanographer from Woods Hole and this is the 4th year of the Stratus Project. The science objectives of the Stratus Project are to observe the surface meteorology and air-sea exchanges of heat, fresh water, and momentum ( friction between the air and sea surface: currents), to observe the temporal evolution of the vertical structure of the upper 500 meters of the ocean, and to document and quantify the local coupling of the atmosphere in this region. Air-sea coupling under the stratus clouds is not well understood and numerical models show broad scale sensitivity over the Pacific to how the clouds and the air-sea interaction in this region are parameterized. The first three deployments of the Stratus moorings are part of EPIC.
EPIC is the Climate Variability study (CLIVAR) with the goal of investigating links between sea surface variability in the eastern tropical Pacific and the climate over the American continents. Important to that goal is an understanding of the role of clouds in the eastern Pacific in modulating the atmosphere-ocean coupling. Previous to this study we really didn’t understand how the stratus clouds were formed off this coast and off the coast of California which has a similar climate and currents. The effect of the ocean temperature and suspended particles (aerosols) on the climate are very important and in these regions are not well understood. Prior to this numerical computer models were used to predict climate changes in these regions but no real studies or observations had been made. These studies will help in the predicition of long term effects of global warming. The Stratus moorings carry two redundant sets of meteorological sensors and the mooring also carries a set of oceanographic instruments. Including Acoustic rain gauges. Acoustic rain gauges are located 50 meters below the buoy on the mooring line. The accoustical rain gauge uses the frequency of the sound of the rain drops hitting the sea surface , the sound varies with amount of rainfall rate. This is more accurate than traditional rain gauges as it averages rainfall over a given area and is not effected by wind. The WHOI Stratus buoys are the most highly instrumented bouys in use today with 31 instruments. Today we deployed two ARGO floats, for more information on ARGO floats please go to the website at: www.argo.ucsd.edu. ARGO floats are a global array of three thousand free drifting profiling floats measuring temp and salinity of the upper 2000m of the ocean. Our watch went well and we deployed our float without breaking it and falling overboard (always a plus:)
Personal Log
Went to sleep last night after my watch at 4am and awoke at 10am. Met with Dr. Kermond and Viviana, the chilean teacher, to go over the science activities for the day. We took some still pictures and worked on the computers. Tomorrow we will begin some interviews with the scientists and crew. Weather was warm and humid, calm sea, some clouds and overall very pleasant. The REVELLE is a beautiful ship that has a very smooth ride, very little rolling motion. It was built in 1996 by the Navy for Scripps Institution of Oceanography. It was named after the former director of Scripps, Dr. Roger Randall Revelle. Revelle believed that the only way to truly study oceanography was to go to sea and he made it a goal while director to increase the number of ships owned by Scripps as well as make sure most if not all oceanographers at Scripps went to sea for some of their research. The REVELLE is 273′ long and 52′ 5″ wide at it’s widest point. Cruising speed of 12 knots, range is 13,000 nautical miles at 10 knots, crew of 22, with a scientific party of 37. It operates approximately 340 days a year worldwide, but mainly in the Pacific. For more information look at the Scripps home page at: www.scripps.ucsd.edu Being on the ship is like being a part of oceanographic history.
Hasta Luego