82
Today, gliders are used primarily for research purposes but many of these field
campaigns are coordinated and jointly supported by ocean observing systems that
archive and display data and assimilate data into regional forecast models. Glider
lines are maintained by the CALCOFI survey discussed above, initially based on
manned oceangoing vessels and now supplemented by glider lines along various
preestablished survey lines normal to the west coast of the USA. The University
Center for Ocean Observation Leadership (RUCOOL), formerly the Rutgers
University Coastal Ocean Observation Laboratory, operates periodic cross-shelf
transects on the wide eastern shelf of the US mid-Atlantic coast and is recognized
for having achieved the first transatlantic glider crossing remotely navigating a
Slocum glider from the US coast to the coast of Spain over a period of 221 days in
2009. The Caribbean Coastal Ocean Observing System (CariCOOS), a component
of the US IOOS program, in collaboration with NOAA’s Atlantic and Meteorological
Laboratory (AOML), seasonally operates a pair of gliders, one in Atlantic Ocean
waters off the north coast of Puerto Rico and one in Caribbean waters off the south
coast of Puerto Rico for hurricane monitoring and research.
3.3 Ocean Observing Satellites in Terrestrial Orbit
Satellite oceanography is a mature field using a number of platform types, sensor
payloads, and technologies (Robinson 2010). Many satellites serve not only as sensor platforms but also as data relay platforms receiving data from land-/ocean-based
autonomous sensor systems and relaying the data to the operator. Additionally, specific satellite constellations are dedicated to navigation and positioning providing
services essential to real-time ocean observing. Sensor systems in turn can be
divided into those bearing passive sensors alone which receive reflected radiation
and active systems that incorporate a radiation source and a backscatter receiver.
Operational satellites travel either in the uppermost range of low earth orbit, at
altitudes of between 700 and 1500 km or in geostationary orbit at an altitude of
35,786 km. Operational environmental satellites in low earth orbit include various
US, EU, and Asian weather and research satellites or satellite constellations that
bear atmospheric terrestrial and ocean sensors as well as data relay systems.
Environmental satellites in low earth orbit are mostly sun synchronous, and in near
polar orbit at altitudes between 700 and 1350 km. Slight inclination of the orbit with
reference to the polar axis of rotation allows orbital precession such that the angle
of solar illumination is invariable except for the apparent seasonal solar displacement. These orbits allow daylight images and near total global coverage with 3–35
orbit repeat periods. For scanning sensors, swath widths of a least 2700 km allow
daily coverage.
Geostationary orbit at an altitude of 35,786 km above the equator allows a satellite to orbit at the same angular rotation as the earth, thus appearing to remain fixed
above a particular point of the equator. The greater distance from the earth results
in telecommunications delays of about 2 s hampering real-time communications
protocols but useful for data relay. Radiometers aboard geostationary weather
3 Platforms for Coastal Ocean Observing
Today, gliders are used primarily for research purposes but many of these field
campaigns are coordinated and jointly supported by ocean observing systems that
archive and display data and assimilate data into regional forecast models. Glider
lines are maintained by the CALCOFI survey discussed above, initially based on
manned oceangoing vessels and now supplemented by glider lines along various
preestablished survey lines normal to the west coast of the USA. The University
Center for Ocean Observation Leadership (RUCOOL), formerly the Rutgers
University Coastal Ocean Observation Laboratory, operates periodic cross-shelf
transects on the wide eastern shelf of the US mid-Atlantic coast and is recognized
for having achieved the first transatlantic glider crossing remotely navigating a
Slocum glider from the US coast to the coast of Spain over a period of 221 days in
2009. The Caribbean Coastal Ocean Observing System (CariCOOS), a component
of the US IOOS program, in collaboration with NOAA’s Atlantic and Meteorological
Laboratory (AOML), seasonally operates a pair of gliders, one in Atlantic Ocean
waters off the north coast of Puerto Rico and one in Caribbean waters off the south
coast of Puerto Rico for hurricane monitoring and research.
3.3 Ocean Observing Satellites in Terrestrial Orbit
Satellite oceanography is a mature field using a number of platform types, sensor
payloads, and technologies (Robinson 2010). Many satellites serve not only as sensor platforms but also as data relay platforms receiving data from land-/ocean-based
autonomous sensor systems and relaying the data to the operator. Additionally, specific satellite constellations are dedicated to navigation and positioning providing
services essential to real-time ocean observing. Sensor systems in turn can be
divided into those bearing passive sensors alone which receive reflected radiation
and active systems that incorporate a radiation source and a backscatter receiver.
Operational satellites travel either in the uppermost range of low earth orbit, at
altitudes of between 700 and 1500 km or in geostationary orbit at an altitude of
35,786 km. Operational environmental satellites in low earth orbit include various
US, EU, and Asian weather and research satellites or satellite constellations that
bear atmospheric terrestrial and ocean sensors as well as data relay systems.
Environmental satellites in low earth orbit are mostly sun synchronous, and in near
polar orbit at altitudes between 700 and 1350 km. Slight inclination of the orbit with
reference to the polar axis of rotation allows orbital precession such that the angle
of solar illumination is invariable except for the apparent seasonal solar displacement. These orbits allow daylight images and near total global coverage with 3–35
orbit repeat periods. For scanning sensors, swath widths of a least 2700 km allow
daily coverage.
Geostationary orbit at an altitude of 35,786 km above the equator allows a satellite to orbit at the same angular rotation as the earth, thus appearing to remain fixed
above a particular point of the equator. The greater distance from the earth results
in telecommunications delays of about 2 s hampering real-time communications
protocols but useful for data relay. Radiometers aboard geostationary weather
3 Platforms for Coastal Ocean Observing