Specification of Fields and Variables

Specification of Fields and Variables

The observing requirements for GOOS are described here in terms of applications and are summarized in the table below. The column headed "variable" specifies such items as "Remote SST" and "Sea Surface Salinity". To view more detailed specifications for the fields in the "variable" column click the field of interest.

For a detailed review of ocean observational requirements for climate on a field by field basis including some fields not included in the table below visit the page Ocean Climate Observations.

The specifications below are derived for the most part from the OOSDP (1995) report and several subsequent publications (Smith et al. 1995; Nowlin et al. 1996). In addition consideration has been given to re-evaluations by the Ocean Observations Panel for Climate. These re-evaluations are included in the meeting reports and reports of various other joint activities of the OOPC with other bodies (see references).

Sampling Requirements for the Global Ocean

CodeApplicationVariableHoriz ResVert ResTime Res# SamplesAccuracy
A
NWP, climate, mesoscale ocean
Remote SST
10 km2
-
6 h
1
0.1-0.3°K
B
Bias correction, trends
In situ SST
500 km2
-
1 week
25
0.2-0.5°C
C
Climate variability
Sea surface salinity
200 km2
-
10 day
1
0.1 PSU
D
Climate prediction and variability
Surface wind
2° x 2°
-
1-2 day
1-4
Dirn: 20% 2 m/s
E
Mesoscale, coastal
Surface wind
50 km2
-
1 day
1
1-2 m/s
F
Climate
Heat flux
2° x 5°
-
month
50
Net: 10 W/m2
G
Climate
Precip.
2° x 5°
-
daily
several
5 cm/month
H
Climate change trends
Sea level
50-1000 km2
-
monthly means
30-50 gauges + GPS with altimetry or several 100s + GPS
1 cm, giving several * 0.1 mm/yr accuracy trends over 1-2 decades
I
Climate variability
Sea level anomalies
100-200 km2
-
month
~ 10
2 cm
J
Mesoscale variability
Sea level anomalies
25-50 km2
-
2 days
1
2-4 cm
K
Climate, short-range prediction
sea ice extent, concen.
~ 30 km
-
1 day
1
10-30 km 2-5%
L
Climate, short-range prediction
sea ice velocity
200 km2?
-
Daily
1
cm/s?
M
Climate
sea ice volume
500 km2
-
monthly
1
~ 30 cm
N
Climate
surface pCO2
25-100 km2
-
daily
1
0.2-0.3 µatm
O
ENSO prediction
T(z)
1.5° x 15°
15 m over 500 m
5 days
4
0.2°C
P
Climate variability
T(z)
1.5° x 5°
~ 5 vert. Modes
1 month
1
0.2°C
Q
Mesoscale ocean
T(z) for large-scale
500 km2
~ 5 modes
10 days
1
0.2°C
R
Climate
S(z)
large-scale
~ 30 m
monthly
1
0.1 PSU
S
Climate, short-range prediction
U(surface)
600 km2
-
month
1
2 cm/s
T
Climate model valid.
U(z)
a few places
30 m?
Mon. means
30
2 cm/s

References

Nowlin, W.D., Jr, N. Smith, G. Needler, P.K. Taylor, R. Weller, R. Schmitt, L. Merlivat, A. V‚zina, A. Alexiou, M. McPhaden, and M. Wakatsuchi 1996: An ocean observing system for climate. Bull. Amer. Met. Soc., 77, 2243-2273.

Ocean Observations Panel for Climate, 1996. Report of the 1st Meeting of the Ocean Observations Panel for Climate, RSMAS, Miami, March 1996, publ. by the IOC.

Ocean Observations Panel for Climate, 1997. Report of the 2nd Meeting of the Ocean Observations Panel for Climate, Cape Town, South Africa, February 1997, publ. by the IOC.

Ocean Observations Panel for Climate, 1998. Report of the 3rd Meeting of the Ocean Observations Panel for Climate, Grasse, France, April 1998, publ. by the IOC.

The Ocean Observing System Development Panel 1995: The Scientific Design for the Common Module of the Global Ocean Observing System and the Global Climate Observing System: An Ocean Observing System for Climate. Report of the OOSDP, publ U.S. WOCE Office, Texas A&M University, College Station Texas, 285 pp. Smith, N.R., G.T. Needler and the Ocean Observing System Development Panel, 1995. An ocean observing system for climate: The conceptual design. Climatic Change, 31: 475-494.

WCRP-103, 1998. The CLIVAR Implementation Plan, The World meteorological Organization, WMO/TD No. 869.