Upload
rosanna-gray
View
215
Download
0
Tags:
Embed Size (px)
Citation preview
Automated Weather Observations from Automated Weather Observations from Ships and Buoys:Ships and Buoys:
A Future Resource for ClimatologistsA Future Resource for Climatologists
Shawn R. Smith
Center for Ocean-Atmospheric Prediction StudiesFlorida State University
Tallahassee, FL USA
OverviewOverview 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 MonitoringExample: 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
Recently this array is transitioning from a research mode to become part of an operational observing system
Photo credit: NOAA/PMEL/TAO Project Office
Needed ObservationsNeeded 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
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 real-time data transmission
Limitations:– Low sampling rates (3-
6 hr)
– Minimal navigation information
– Incomplete metadata
Ships: The early daysShips: The early days
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
Ships: AutomationShips: Automation
Photo credit: WHOIPhoto credit: WHOI
Photo credit: NOAA
Typical AWSTypical 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: futureAutomation: 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: Southampton Oceanography CentrePhoto Credit: WHOI
AWS ApplicationAWS 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 ApplicationAWS Application R/V-AWS observations have also been used for validating satellite
wind sensors (e.g., Bourassa et al., 2003, J. Geophys. Res.)
Wind Direction Wind SpeedSeaWinds on Midori
Final ThoughtsFinal 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])