ar50 
A. Valente et al.: A compilation of global bio-optical in situ data 
Table 3. Summary of median values for “aph””, “adg”, and “bbp” at 44X and 55X nm for each data set (as shown in Fig. 12a-f). Data were 
first searched at 445 and 555 nm, and then with a search window up to 8 nm, to include data at 547 nm. 
In 
Median “aph” | Median “adg” ! Median “bbp” 
44xnm 55xnm | 44xnm 55xnm ' 44xnm 55xnm 
0.0035 0.0025 
0.0080 0.0052 
0.0030 0.0022 
0.0047 0.0037 
SeaBASS 0.0712 0.0117 
MERMAID 0.0282 0.0052 
NOMAD 0.0353 0.0046 
COASTCOLOUR 0.0665 0.0096 
AWI 0.0239 0.0048 
TPSS 0.0454 0.0077 
0.0711 0.0222 
0.1149 0.0286 
0.0515 0.0112 
0.1259 0.0175 
T ua... 
a 
' 
KA 
zn 
0 
60 
* 
gr 
"480° 
ll— 
„1205 
$aph 9adg ® - dg ®aph & adg & bbp ®aph & bb es 
ph 9adg ®aph & adg ®aph & adg & bbp ®ap p 95bp_ 
50° 60° 120° 181 
Figure 14. Global distribution of observations of inherent optical properties (algal pigment absorption coefficient “aph”, detrital plus CDOM 
absorption coefficient “adg””. and particle backscattering coefficient “bbp””) in the final table. 
(erest to preserve this data set as a whole. Also, not discarding 
these data allows further manipulation with different quality 
control criteria. On the annual scale, the observations of the 
ınherent optical properties continue to be strongly underrep- 
-esented in the Southern Hemisphere where there is a com- 
plete absence of data during the austral winter (Fig. 3). The 
new “aph” data in the present version have only increased 
the spatial coverage in the Arctic region. Overall, the geo- 
graphic coverage for observations of “aph”, “adg”, and “bbp” 
(Fig. 14) is poor, with most open ocean regions not being 
sampled, except for the Atlantic Ocean. Small clusters of 
data are in specific coastal regions, such as the western coast 
of North America. 
Finally, for the diffuse attenuation coefficient for down- 
ward irradiance (“kd”, not updated in present version), there 
are 25 unique wavelengths between 405 and 709 nm. The to- 
tal of 2454 observations is divided between NOMAD (2266), 
SeaBASS (118), and MERMAID (70). Data distribution of 
“kd” at 44X nm and 55X nm for each data set is shown in 
Fig. 12g and h. No “kd” data at these wavelengths were avail- 
able for the SeaBASS data set (only at 490 nm). Median val- 
ues of “kd” at 44X nm span between 0.08 m7! (NOMAD) 
and 0.1 m7! (MERMAID), whereas at 55X nm the “kd” val- 
carth Syst. Sci. Data, 14. 5737-5770. 202% 
ues are approximately 0.1 m”! (NOMAD and MERMAID). 
The best geographical coverage is provided by NOMAD 
(Fig. 15), with a higher coverage in the Atlantic, compared 
with other oceans. Except for the coastal regions of North 
America and the Japan Sea, most coastal regions are not sam- 
pled. In the Northern Hemisphere, “kd”’ is distributed evenly 
across all months of the year, but in the Southern Hemisphere 
there are few data points during the austral winter (Fig. 3). 
For total suspended matter (““tsm”; not updated on present 
version), there is a total of 1546 observations divided be- 
tween COASTCOLOUR (1199) and MERMAID (347). The 
observations of “tsm” are available in a greater number in 
the Northern Hemisphere (Fig. 3) and are distributed across 
several coastal regions around Europe, Mediterranean Sea, 
China Sea, Indonesia, and Australia (Fig. 15). 
Although most of the stations with concurrent variables 
are from the NOMAD data set, for completeness, an exX- 
amination of bio-optical relationships is provided (Fig. 16). 
The relation between “aph” at 443 nm and chlorophyll-a 
(Fig. 16a) agrees with Bricaud et al. (2004). A total of 
3387 points exist with these two variables available (29 % 
from NOMAD, 28 % from TPSS, 22 % from AWI, 10% 
from COASTCOLOUR, and remaining 11% from MER- 
httos://doi.org/10.5194/essd-14-5737-2022