Discrete chlorophyll and phaeopigment series measured by CEFAS on POL Coastal Observatory cruise 11, RV Prince Madog cruise PD34_03
Data Originator
Naomi Greenwood, CEFAS, Lowestoft
Content of data series
| Parameter | Units | Parameter code | CTD Samples |
|---|---|---|---|
| Chlorophyll-a concentration | mg m -3 | CPHLFLP1 | 8 |
| Chlorophyll-a concentration standard deviation | mg m -3 | CLSDFLP1 | 8 |
| Phaeopigment concentration | mg m -3 | PHAEFLP1 | 8 |
| Phaeopigment concentration standard deviation | mg m -3 | PHSDFLP1 | 8 |
Originator's Protocol
Samples for chlorophyll-a and associated phaeopigments were collected from water bottle rosette sampling systems mounted on the lowered CTD. 24 samples were collected near-surface from a total of 8 CTD stations.
For each sample, a 250ml sample is passed through Whatman GF/F filter under low vacuum. The filter paper is folded in half, loosely wrapped in aluminium foil and placed in plastic bag. Samples are stored in this way in a box containing desiccant at -18° C until analysis. Filters are extracted using 8ml 90% acetone and measured fluorometrically according to Tett (1987) for chlorophyll-a and phaeopigments. CEFAS use a Turner 10AU field fluorometer, which has been calibrated using a pure solution of chlorophyll-a.
BODC Processing
The data were supplied to BODC as an Excel spreadsheet. This was converted to an ASCII format file for loading into the BODC archive. Methodology and units were checked against information held in the BODC parameter dictionary and an appropriate parameter code was attributed to each variable. The file's data and metadata fields were then checked prior to loading into a database.
CEFAS took surface samples at Station 1 at 13:00 HRS. No CTD logsheet data were available for this time, nor was there a station entry in the cruise log. However, a CTD logsheet was available for 13:57 GMT (cast C03). The logsheet data and bottle firing records for the cruise were examined. These indicated that it was highly probable that the CEFAS samples taken at 13:00 HRS were taken during cast C03 with the discrepancy between the records being due to differences between GMT and local time. Therefore, the CEFAS surface samples for 13:00 HRS were linked to rosette bottles fired during cast C03.
The data were loaded into the database under the Oracle Relational Database Management System by matching the sample's station identifier and depth with the information already held in the database for this cruise. Where the data supplied included multiple replicates for each station, the mean value and standard deviation were loaded into the database. For single samples, the data were loaded without further modification.
Comments on data quality and outstanding issues
There are no data quality issues regarding this dataset.
References
Tett , P. 1987. Plankton. In: Baker, J. M., Wolff, J. W. (Eds.), Biological surveys of estuaries and coasts. Cambridge University Press, Cambridge, pp 280-341.
Conditions of Use
CEFAS Disclaimer:
"Reproduction of this material is limited to academic and educational uses only and not for any commercial purposes without permission from CEFAS. The data are provided "as is" and in no event shall CEFAS be liable for any damages, including, without limitation, any disruption, damage and/or loss to your data or computer system that may occur while using this site or data. CEFAS makes no warranty, express or implied, including the warranties of merchantability and fitness for a particular purpose; nor assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any data, information, apparatus, product, or process disclosed; nor represents that its use would not infringe the rights of any third party."
The Data Originator must be informed that the supply has occurred.
Due acknowledgement of the Originator and the Originator's Institute is made by the receiver in any product using the data.
No commercial gain ensues from usage of the data.
