TOGA (WCRP’s Tropical Ocean Global Atmosphere Study) were the early beneficiaries but
POMS also led to the Ocean Observing System
Development Programme (OOSDP), organized for
CCCO by Francis Bretherton, which addressed
the wide range of oceanographic and atmospheric
measurement systems that needed either reinforcement or design and development. The OOSDP
(Intergovernmental Oceanographic Commission,
1984) was later turned into the JSC/CCCO OOSD
Panel led by Worth Nowlin. The Panel produced a
valuable series of scientific reports that led to a
design for an ocean observing system for climate,
more specifically the climate component of the
Global Ocean Observing System (GOOS). Most
recently, the Climate Variability and Predictability Study (CLIVAR) Implementation Plan (World
Climate Research Programme, 1998) to some
extent builds on the observing systems that
became prominent during WOCE and TOGA and
the proposals emanating from the OOSD Panel’s
report.
The expectation that new information over all
(or large parts) of the ocean from satellites would
be available by the late 1980s, meant that coordination of satellite missions was desirable and
that the requirements of the oceanographic and
meteorological communities should be taken into
account. JSC and CCCO called a meeting in
Chilton, UK, in January 1981 to identify how
(with some adjustment to schedules, orbits and
sensing capabilities) projected satellites could form
an essential and complementary set of observing
systems to the planned in-situ oceanographic
experiments (World Climate Research Programme,
1981). The NASA, ESA and NASDA space agency
participation (from the USA, Europe and Japan)
ensured that they were aware of the scientific
needs. The recommendations of the meeting were
addressed immediately by the JSC and CCCO.
Both gave priority to an altimeter with subdecimetre accuracy, to determination of the geoid,
and to scatterometer measurements of the surface
wind field as well as identifying a host of other
critical satellite coordination issues. CCCO considered that the 5-year mission duration suggested by
the meeting was barely adequate to define the
annual cycle in many parts of the ocean. They also
noted that many important oceanographic phenomena had return intervals longer than 5 years.
Hence they requested extended satellite coverage.
Michel Lefebvre (personal communication)
recalls that, at Chilton, the US proposal was discussed for TOPEX, a satellite carrying an optimized sub-decimetre precision altimeter. Moreover,
in January 1978, a European group meeting in
Schloss-Elmau (European Space Agency, 1978)
had proposed an altimeter mission to ESA. Neither
proposal gained immediate acceptance from the
agencies. The European proposal eventually became
incorporated in the successful but less-optimized
multisensor ERS missions, while TOPEX was in
competition with wind measuring and to a lesser
extent, geodetic missions. Both these missions
would contribute valuably but TOPEX was pivotal
to WOCE’s success.
Later in 1981, French scientists won the
approval of Centre National d’Études Spatiales
(CNES), and strong ministerial support, for
POSEIDON, an altimeter to be flown on the
French SPOT satellite. SPOT also carried a new
global tracking system DORIS dedicated to, and
optimized for, altimetry using an onboard receiver
and a worldwide network of 50 stations. It is
extensively used also for gravity field improvement. The case for a dedicated altimeter mission to
make a unique and vital contribution to WOCE
was immensely strengthened as France and the
USA in the succeeding years developed a joint proposal for a TOPEX/POSEIDON (T/P) satellite to
be launched on a French Ariane rocket. It would
carry US and French altimeters and tracking systems in an orbit precisely optimized for WOCE.
The Memorandum of Understanding between the
two countries, signed in 1987, envisaged laying
the foundation for a follow-on after T/P (Michel
Lefebvre, personal communication; Ratier, 1988).
In May 1981, CCCO established a WOCE
Design Options Study Group chaired by Francis
Bretherton. It was charged with reporting to JSC
and CCCO (after presenting the preliminary plans
to the Tokyo Conference on Large-Scale Oceanographic Experiments in the WCRP, in May 1982).
Some significant points raised by CCCO were that:
¥ altimetry with simultaneous scatterometry was
essential;
¥ variability of sea surface topography should be
easier to measure and be of more significance
for climate variability than the mean;
¥ many areas of the oceans needed to be covered with a network of surface to near-bottom
1.3 The Origins, Development and Conduct of WOCE
35
Thompson, Crease and Gould
POMS also led to the Ocean Observing System
Development Programme (OOSDP), organized for
CCCO by Francis Bretherton, which addressed
the wide range of oceanographic and atmospheric
measurement systems that needed either reinforcement or design and development. The OOSDP
(Intergovernmental Oceanographic Commission,
1984) was later turned into the JSC/CCCO OOSD
Panel led by Worth Nowlin. The Panel produced a
valuable series of scientific reports that led to a
design for an ocean observing system for climate,
more specifically the climate component of the
Global Ocean Observing System (GOOS). Most
recently, the Climate Variability and Predictability Study (CLIVAR) Implementation Plan (World
Climate Research Programme, 1998) to some
extent builds on the observing systems that
became prominent during WOCE and TOGA and
the proposals emanating from the OOSD Panel’s
report.
The expectation that new information over all
(or large parts) of the ocean from satellites would
be available by the late 1980s, meant that coordination of satellite missions was desirable and
that the requirements of the oceanographic and
meteorological communities should be taken into
account. JSC and CCCO called a meeting in
Chilton, UK, in January 1981 to identify how
(with some adjustment to schedules, orbits and
sensing capabilities) projected satellites could form
an essential and complementary set of observing
systems to the planned in-situ oceanographic
experiments (World Climate Research Programme,
1981). The NASA, ESA and NASDA space agency
participation (from the USA, Europe and Japan)
ensured that they were aware of the scientific
needs. The recommendations of the meeting were
addressed immediately by the JSC and CCCO.
Both gave priority to an altimeter with subdecimetre accuracy, to determination of the geoid,
and to scatterometer measurements of the surface
wind field as well as identifying a host of other
critical satellite coordination issues. CCCO considered that the 5-year mission duration suggested by
the meeting was barely adequate to define the
annual cycle in many parts of the ocean. They also
noted that many important oceanographic phenomena had return intervals longer than 5 years.
Hence they requested extended satellite coverage.
Michel Lefebvre (personal communication)
recalls that, at Chilton, the US proposal was discussed for TOPEX, a satellite carrying an optimized sub-decimetre precision altimeter. Moreover,
in January 1978, a European group meeting in
Schloss-Elmau (European Space Agency, 1978)
had proposed an altimeter mission to ESA. Neither
proposal gained immediate acceptance from the
agencies. The European proposal eventually became
incorporated in the successful but less-optimized
multisensor ERS missions, while TOPEX was in
competition with wind measuring and to a lesser
extent, geodetic missions. Both these missions
would contribute valuably but TOPEX was pivotal
to WOCE’s success.
Later in 1981, French scientists won the
approval of Centre National d’Études Spatiales
(CNES), and strong ministerial support, for
POSEIDON, an altimeter to be flown on the
French SPOT satellite. SPOT also carried a new
global tracking system DORIS dedicated to, and
optimized for, altimetry using an onboard receiver
and a worldwide network of 50 stations. It is
extensively used also for gravity field improvement. The case for a dedicated altimeter mission to
make a unique and vital contribution to WOCE
was immensely strengthened as France and the
USA in the succeeding years developed a joint proposal for a TOPEX/POSEIDON (T/P) satellite to
be launched on a French Ariane rocket. It would
carry US and French altimeters and tracking systems in an orbit precisely optimized for WOCE.
The Memorandum of Understanding between the
two countries, signed in 1987, envisaged laying
the foundation for a follow-on after T/P (Michel
Lefebvre, personal communication; Ratier, 1988).
In May 1981, CCCO established a WOCE
Design Options Study Group chaired by Francis
Bretherton. It was charged with reporting to JSC
and CCCO (after presenting the preliminary plans
to the Tokyo Conference on Large-Scale Oceanographic Experiments in the WCRP, in May 1982).
Some significant points raised by CCCO were that:
¥ altimetry with simultaneous scatterometry was
essential;
¥ variability of sea surface topography should be
easier to measure and be of more significance
for climate variability than the mean;
¥ many areas of the oceans needed to be covered with a network of surface to near-bottom
1.3 The Origins, Development and Conduct of WOCE
35
Thompson, Crease and Gould