Frequently asked questions bout ocean observations
http://www.aoml.noaa.gov/phod/tsg/index.php
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- 3.7) What is an ATLAS mooring
- 3.8) What observations are provided by satellite
- 4. Questions related to the management and distribution of ocean observations What is data management
http://www.aoml.noaa.gov/phod/tsg/index.php 3.6) What is an IES (Inverted Echo Sounder)? An IES is a fairly simple instrument consisting mainly of a transducer, which can produce sound waves and hear sound waves, and a precise clock. The IES used at AOML send out a series of 24 10 kHz or 12Khz sound pulses each hour. These pulses reflect when they hit the ocean surface and 1-8 seconds later the IES records the precise amount of time between when each pulse was transmitted and when the pulse was heard returning to the IES. The round trip travel times for the 24 pulses are then processed to determine the travel time for that hour (multiple pulses are needed to average out the changes in travel time due to waves at the ocean surface and other sources of noise). Because the speed of sound in seawater is dependent on temperature (and weakly upon salinity), as the water temperatures above the IES change over time the travel time measurement of the IES changes. These changes in travel time are small, measured in milleseconds, but with a precise clock these time changes can be accurately determined. The travel time of the IES is combined with other ocean measurements of temperature and salinity in order to estimate full-water-column profiles of temperature, salinity and density. The result is a time series of profiles of these quantities at each IES site. Some of these instruments are equipped with additional sensors, most commonly a high precision bottom pressure sensor, with the instrument then called a PIES, and in some cases with a single-depth acoustic current meter tethered 50 m above the bottom, referred to as a CPIES. IES/PIES/CPIES arrays are placed in areas of large ocean variability such as the Gulf Stream and areas where intense eddies (also called rings) are formed such as the western tropical Atlantic. The data they provide are used to characterize the spatial and temporal variability of these features in order to improve understanding of the causes of ocean variability. For more information on the IES activities and other instrument development projects of the Physical Oceanography Division of NOAA’s Atlantic Oceanographic and Meteorological Laboratory go to: http://www.aoml.noaa.gov/phod/instrument_development/index.php Figure legend: An inverted echo sounder place in an Adaptable Bottom Instrument Information Shuttle System (ABIISS). The bottom-mounted instrument includes pods that are released to the surface at pre-selected times. Data collected while on the bottom are transmitted to satellites then to land stations permitting longer deployments and reducing ship-time costs. 3.7) What is an ATLAS mooring? An ATLAS mooring is an instrument string anchored to the seafloor. The mooring also includes a surface float from which observations are also collected. Wire rope is used in the upper 700 meters of the mooring to reduce fish bite damage. Nylon line is used for the remainder of the mooring. ATLAS moorings are typically deployed in the tropical oceans. The surface buoy is a 2.3 m diameter fiberglass-over-foam toroid, with an aluminum tower and a stainless steel bridle. When completely rigged, the system has an air weigh of approximately 660 kg, a net buoyancy of nearly 2300 kg and an overall height of 4.9 m. Standard meteorological instrumentation on the surface float includes wind, long and short wave radiation, rain, relative humidity and barometric pressure sensors. Oceanographic sensors on the float include sea surface temperature and salinity. Hardware on the wire includes pressure, temperature and salinity sensors. Several moorings are also equipped with current meters. The tropical oceans play an important role in global climate. ATLAS moorings provide the atmospheric and oceanographic data needed to characterize, understand and ultimately predict tropical variability and it’s affect on global climate. ATLAS data are also used to initialize seasonal-to-interannual climate forecast models. 
For more information on the Atlas mooring activities of the Physical Oceanography Division of NOAA’s Atlantic Oceanographic and Meteorological Laboratory go to: http://www.aoml.noaa.gov/phod/pne/index.php 3.8) What observations are provided by satellite? Oceanographic sensors placed on satellites include observations of SST, sea surface height anomaly, and surface ocean color. New sensors are being developed to observe sea surface salinity from space. Coverage is global with temporal coverage of individual locations dependent on the satellite orbit.  
Figure Legend: Left panel: Sea surface height anomaly in the Gulf of Mexico. Right Panel: Sea surface temperature in the Gulf of Mexico. Both satellite products are used in forecasting hurricane intensity and trajectories. The satellite coverage of SST, sea surface height anomaly and surface ocean color are used to provide global representations of these variables. SST data can be used in forecasts of hurricane intensity and tracklines. SST and surface ocean color can be used to characterize the distribution of surface biota ranging from harmful algae blooms to commercial fisheries. SST and altimetry are also used to initialize seasonal-to-interannual climate forecasts.
http://www.aoml.noaa.gov/phod/satprod/index.php 4. Questions related to the management and distribution of ocean observations What is data management? Data management is the process of changing measurement units (e.g., often electrical) to physical units and then performing a series of tests to ensure that data are suitable for the purpose collected. A typical first-step in data management is adding meta-data to the measurement record. Meta-data provides the information needed to reduce a sensor record to a physical record and should include (but unfortunately often does not) information on the type of sensor used, manufacturer, calibration factors, etc. Raw data are then transformed to physical units. Quality control of the data is frequently the next step in data management. Quality control can be performed by automatic computer routines (i.e., no operator involvement) or by a scientist. The former quality control is most often performed by operational agencies which require data in real-time for forecast applications. The latter quality control is performed when a higher quality of data is required for research. Data and meta-data are put into formats developed by international data management committees and then forwarded to national and international facilities for archiving and user access. 
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