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Automated Weather Observations from Ships and Buoys: A Future Resource for Climatologists Shawn R. Smith Center for Ocean-Atmospheric Prediction Studies Florida State University Tallahassee, FL USA Overview The need for in-situ climate data is not limited to land stations Knowledge of air-sea fluxes (e.g., heat, water, carbon) is essential for understanding global climate processes NOAA is spearheading the U. S. effort to expand and improve the network of in-situ observations from the global oceans Image from NOAA OGP Example: ENSO Monitoring Prior to the 1982/83 El Niño, in-situ observations of the tropical Pacific were limited to merchant ships and island stations. Along came TAO/TRITON – PMEL began installing and maintaining a continuous network of moored buoys – Data from these buoys improved analyses (e.g., FSU winds) used to force models – Provided a data resource to better understand ENSO as part of the climate Photo credit: NOAA/PMEL/TAO Project Office Recently this array is transitioning from a research mode to become part of an operational observing system Needed Observations Ideally in-situ measurements near the ocean surface should provide all parameters needed to resolve air-sea fluxes – Meteorology: Winds, air temperature, humidity, pressure, precipitation, radiation (multiple components) – Sea surface: Temperature, salinity, sea state, ice cover – Precise platform navigation (location, orientation, earth-relative motion) High data accuracy and sampling rates are desired Detailed metadata are also essential (instrument heights, exposures, etc.) Must go beyond the tropics, into harsh operational environments (e.g., Southern Ocean, North Pacific) Photo credit: USCG Ships: The early days For the last century, the primary source of weather data over the ocean was observations made by merchant vessel operators Data primarily collected manually and submitted upon arrival in suitable port GTS provided for realtime data transmission Limitations: – Low sampling rates (36 hr) – Minimal navigation information – Incomplete metadata Ships: Automation More recently advancements in computer technology has led to the deployment of automated weather systems (AWS) First deployed on research vessels and buoys In the past 5 years, new initiatives have deployed sensors on volunteer observing ships (merchant ships, yachts, cruise ships) Initial development underway for moored platforms in extreme environments Photo credit: NOAA Photo credit: WHOI Photo credit: WHOI Typical AWS High-resolution marine AWS – Sampling rates 1-60 minutes – Continuous recording – Typically bow or mast mounted on R/V Photo credit: WHOI – Data rarely available in real-time (good for independent validation) Automation: future Standard meteorological package – Fluxes are determined using a bulk modeling approach Experimental system – Directly measure fluxes – Example: Southampton Oceanography Center AutoFlux – Hourly fluxes sent in real time Photo Credit: WHOI Photo credit: Southampton Oceanography Centre AWS Application Quality processed AWS data are ideal for evaluation of global reanalysis fluxes (e.g., Smith et al., 2001, J. Climate) Sampling rates allow accurate estimation of 6 hourly integrated fluxes AWS Application R/V-AWS observations have also been used for validating satellite wind sensors (e.g., Bourassa et al., 2003, J. Geophys. Res.) SeaWinds on Midori Wind Direction Wind Speed Final Thoughts A new initiative is underway to ensure routine delivery of calibrated, quality assured, surface meteorological data collected using AWS on research vessels, volunteer observing ships, and new moored platforms. User input is essential – Marine AWS data are a new resource for climatologists – Climatologists are asked to provide input to network design Sampling rates, platform locations, parameters desired Second workshop on role of marine AWS in a sustained ocean observing system is planned for 17-18 April 2004 (Silver Spring, MD) – Plan to open discussions with user community (modelers, satellite programs, etc.) – Discussion will focus on implementation plans, data user needs, and coordination between R/V, VOS, and buoy programs – Interested participants should contact ([email protected])