Path: santra!tut!draken!kth!mcvax!uunet!yale!cmcl2!ccnysci!patth From: patth@ccnysci.UUCP (Patt Haring) Newsgroups: sci.space Subject: NASA Aircraft to Support Int'l. Global Ocean Study Message-ID: <1710@ccnysci.UUCP> Date: 24 Apr 89 17:54:48 GMT Reply-To: patth@ccnysci.UUCP (Patt Haring) Organization: City College Of New York Lines: 148 Ported to UseNET from UNITEX Network 201-795-0733 via Rutgers FidoGATEway *NASA AIRCRAFT TO SUPPORT INTERNATIONAL GLOBAL OCEAN STUDY Paula Cleggett-Haleim Headquarters, Washington, D.C. April 19, 1989 (Phone: 202/453-1548) Joyce B. Milliner Goddard/Wallops Flight Facility, Wallops Island, Va. (Phone: 804/824-1579) NASA's highly instrumented, remote sensing aircraft will participate in an international oceanographic experiment, called the Global Ocean Flux Study (GOFS), to determine the capacity of the world's oceans to assimilate and store excess carbon dioxide (CO2) from Earth's atmosphere. The study results are critical to predicting potential temperature increases in world climate due to the large increase in atmospheric CO2 caused by the burning of fossil fuels. The increased atmospheric carbon dioxide may lead to a warmer Earth through the "greenhouse effect." The ocean is an important reservoir for CO2. Some estimates indicate that the ocean has absorbed nearly half of the increased CO2 produced. Additionally, CO2 constantly is being exchanged between the ocean and atmosphere. A vital input needed for climactic research is predicting the portion of the CO2 entering the ocean that will be effectively trapped or removed. In polar regions, the cold ocean surface layer sinks in some areas and becomes part of deep ocean bottom water where the entrained CO2 is effectively removed from contact with the atmosphere for long periods of time. A second important process is removal of CO2 by biological processes. Carbon dioxide from the surface layer is utilized in the marine photosynthetic process where CO2 is combined with water to form biomass. Some of this biomass is consumed in the marine food chain where a portion is released back into the water column and potentially, to the atmosphere through respiration. An unknown amount of plant and animal biomass sinks through the water column to the sea floor. Knowledge of these processes and rates also will provide scientists with information to make improved estimates of climactic changes. The NASA four-engine, P-3A turboprop aircraft, from Goddard Space Flight Center's Wallops Flight Facility, Wallops Island, Va., is equipped to measure the concentration of phytoplankton biomass in the upper ocean layer. The primary instrument, the airborne oceanographic lidar (AOL), will use a blue-green laser to stimulate fluorescence from chlorophyll contained in phytoplankton, the microscopic plants at the bottom of the marine food web. Previous aircraft chlorophyll fluorescence measurements have been shown to be highly correlated with chlorophyll concentration measurements made on board ships with standard pigment extraction techniques. In addition, other instrumentation associated with -- the AOL will be used to measure solar induced responses associated with phytoplankton in numerous bands spread across the entire visible spectrum. Over the past decade, remote-sensing scientists have been increasingly successful in deriving reliable chlorophyll concentration values from certain combinations of these passive spectral bands. The combination of laser-induced fluorescence measurements and the passive spectra will be used to further improve the potential for measuring chlorophyll from solar induced ocean color alone. The Global Ocean Flux Study efforts include scientists and research vessels from West Germany, Canada, Great Britain, the Netherlands and the United States. The study is expected to continue over the next 10 years, each year concentrating on resolving unknown aspects involving the marine carbon and related biogeochemical cycles. The initial experiment involves studies of the spring phytoplankton bloom in the eastern North Atlantic Ocean. The U.S. research vessel, the Atlantis II from Woods Hole Oceanographic Institute, has placed instrumented moorings at two sites along the 20 west meridian. The Atlantis II, along with research vessels from the other participating nations, will study related phytoplankton productivity as the bloom moves northward in response to increasing solar radiation and the development of thermal stratification in the upper ocean. The NASA aircraft will participate in the spring bloom study for a 6-week period beginning April 20. The aircraft surveys will be staged from Lajes, Azores; Shannon, Ireland; and Keflavik, Iceland. The NASA aircraft will be used to map 62 to 124 mile areas of the ocean surrounding each of the moorings. Maps showing the regional concentration of chlorophyll and sea surface temperature will be sent to the research vessels through a satellite transmission. Knowledge of the distribution of phytoplankton and sea surface temperature will be used by the scientists on board the research vessels to position the ships during the experiment and thus, optimize the time-series sampling conducted from the ships. Following the completion of aircraft deployment, the surface layer chlorophyll maps, developed from the airborne data, will be used to aid in the interpretation of the observations made from the individual research vessels. Launches of satellite ocean color scanners, proposed for the mid-late 1990's, will enable remote sensing scientists to gauge surface layer phytoplankton and production over wide areas of the ocean on a continual basis, considerably augmenting measurements made from ships and aircraft. Similar chlorophyll estimates made from the coastal zone color scanner, an ocean scanner on NASA's Nimbus 7 spacecraft which functioned for an 8-year period beginning in 1978, have allowed scientists from Goddard Space Flight Center's Laboratory for Oceans to provide maps of world-wide chlorophyll distribution which have been very valuable in planning the Global Ocean Flux Study. There currently are no ocean color satellite sensors in orbit. The earliest that such a satellite could be placed in orbit is late in 1992, which is the proposed launch date for the Compact Wide Field Spectrometer ocean color sensor. * Origin: UNITEX --> Crime Stoppers Against the New Age Hustle (1:107/501) -- unitex - via FidoNet node 1:107/520 UUCP: ...!rutgers!rubbs!unitex ARPA: unitex@rubbs.FIDONET.ORG -- Patt Haring rutgers!cmcl2!ccnysci!patth patth@ccnysci.BITNET