Collected Data of High Temporal-Spatial Resolution Marine Biogeochemical
Monitoring from Ferries 
in the East Asian Marginal Seas 
(April 1994 - December 1995)

Edited by Akira Harashima

National Institute for Environmental Studies, Environment Agency of Japan
16-2 Onogawa, Tsukuba, Ibaraki 305, Japan

Abstract: 	This CD-ROM contains the data of a marine environmental
monitoring program using 2 ferries, which followed up the previous Japan-
Korea Ferry monitoring between Pusan and Kobe1)-3) carried out in 1991-
1993 (hereinafter referred to as Line (a)).  The new program is using 2 ferry
cruise tracks: Line (b)Osaka - Seto Inland Sea - Beppu and Line (c) Osaka -
Kuroshio Current - Okinawa.   The policy of the newly selected geographical
coverage is to take over the time series for the Seto Inland Sea part of Line
(a) by implementing (b) and to cover the zonation structure between the
inner bay - shelf slope - oligotrophic Kuroshio Current by implementing Line
(c). This CD-ROM contains numerical data from continuous sensor measurements (T, S, pH, and fluorescence) and from automated filtration
sampling ( dissolved nutrients, chlorophyll-a, and phaeopigments ).  It also
includes computer-generated images that will help the users visualize the
temporal-spatial variations of the parameters.    

1. Introduction
	Increases in the extent of human activities have strongly impacted the
cycling of elements such as C, N, and P.  The changes in these cycles would
occur first in the marginal seas and the establishment of monitoring
systems to assess such changes is urgently needed,  particularly in the
waters neighboring the Asian countries.  
	To comprehend the mechanisms and processes of environmental changes, monitoring programs with the following characteristics should be
implemented: (1) long duration, (2) sampling frequency sufficient to resolve
phenomena over various spatial and temporal scales, (3) linkage with
satellite missions, particularly those with ocean color sensors7), (4)
robustness of the methods, (5) linkage with modeling efforts, (6) minimization of costs, (7) quick processing and distribution of the data
products in both numerical and  graphic form, and (8) holistic approach for
the comprehensive understanding of ecosystem health.
	 Biogeochemical monitoring using the sea water intake of ferries was
evaluated with respect to these needs and found to be feasible.  We developed a prototype system in 1990 and deployed it on a ship track on Line
(a) (Fig.1).  The procedures necessary for such monitoring have been described in other reports1), 2).  The initial numerical data and image files
were published in a CD-ROM3) and distributed to pertinent organizations
including the Japan Oceanographic Data Center  (JODC).  One can browse the
contents of the CD-ROM at the CGER world wide web site,
URL: http://www-cger.nies.go.jp/cger-e/marine/d007.html
	 The ferry service sailing  Line (a) ceased operation in 1993.  Therefore,
new ferry tracks were selected based on the criteria discussed below. 

2. Geographical Coverage of the Monitoring
	 The program since 1994 has been based on the following 2 ferry tracks. 
Line (b) traverses the Seto Inland Sea, a characteristic semi-enclosed sea
heavily affected by anthropogenic impacts. Line (c) traverses the zonation
structure from a semi-enclosed sea, across the shelf slope, and into the
Kuroshio Current.  Both ships belong to Kansai Kisen Co., Ltd.  Thus the
combination of results from these 2 lines facilitates assessment of both
anthropogenic trends and background characteristics.   The latter role was
played in part by the Tsushima Strait portion of the Line (a) cruise track. 
The Tsushima Current stems from the subtropical gyre in the area around
Okinawa and Kyushu and flows in this strait, entraining the water of the
East China Sea.  
	 On Line (c), the southbound and northbound tracks differ from each
other because the ship takes advantage of the northeast-component of the
Kuroshio when sailing north, but avoids it by taking a route nearer to the
coast on the southward leg.  Furthermore, several northbound cruises sail a
course in the East China Sea via Nagasaki for special cruises (Fig. 1).  

3.Measurement Methods
	 The equipment and methods used on Line (b) (Fig. 2) are basically
identical to those used on Line (a).  Water temperature(T), salinity (S), pH,
and dissolved oxygen were obtained by integrated water quality sensors
(Hydrolab H20).  The in vivo fluorescence was measured by a Turner Design
Fluorometer.  Automated filtration sampling for dissolved nutrients,
chlorophyll-a, and phaeopigments was done at 24 points every other week
only on Line (b). The weekly maintenance (retrieval of the data and samples
and calibration and readjustment of the sensors) was done while the ships
were at Osaka Port.  An inventory of the data from these 2 series of cruises
are listed in the APPENDIX.TXT file on the CD-ROM.  All other differences
between the methods used on Lines  (b) and (c) are listed in Table 1.

Table.1  Difference between the methods for Line (b) and (c).

Furthermore, attended investigations were occasionally carried out on both
ferry lines to perform research-oriented experiments or optional measurements simultaneous with regular monitoring.  Although the results
of such supplemental measurements are omitted here and left  for individual
research publications5),6), the dates and lists of measured variables from
supplemental measurements are listed in the APPENDIX.TXT file on the CD-
ROM. 

4. Data Processing
	 Details of the regular monitoring methods are shown in other reports1),2),4) and some points are briefly repeated here. The sensor signals
more or less drift to some extent over the course of each week of continuous flow-through measurements due to the gradual fouling of their
seaward-facing surfaces.  Therefore, the data were processed as follows. 
At first, Level-1 data is generated as a text file converted from the raw
binary data.  Level-2 data of T, S, in vivo fluorescence, and DO were then
computed by correcting the Level-1 data with the calibration values for
before and after each weekly measuring period, assuming that the fouling is
linear with time.  This CD-ROM contains Level-2 data, each numerical file of
which corresponds to a one-way cruise. 
	Two kinds of corrected data of pH were generated.  Using only the
calibration value for before each week of continuous measurements, the pH1
data series was generated without temperature correction.  Using the
calibration values for before and after each week, the pH2 data series was
generated assuming that water temperature was 25 deg. and that sensor
drift was linear with time during the continuous measurements.
	 While we include oxygen values for reference, their accuracy can not be
assured because the one week cruise durations exceeded the expected life of
the probe membranes.  The fluorescence values are recorded in units of
fluoresceine solution (used for calibration) equivalent concentrations . 
Based on the correlation between them, the chlorophyll-a concentration (in
microgram kg-1) was around 1/4 of the fluorescence value.  The quality of
the Level-2 fluorescence data was sometimes degraded by non-linear drift
of the sensor with time.
	  Especially, the data in the oligotrophic part of Line(c) could not be
validated.   However, they were not omitted because they would contribute
in a sense of relative values to the analysis of phytoplankton patchness or
the frontal structure.  
	  Images such as those in  (e.g., Fig. 3 for in vivo fluorescence in 1994)
were generated to comprehensively reveal the temporal-spatial variation of
variables. To produce such images, a text matrix was generated so that each
row expresses the spatial distribution obtained from each cruise and each
column expresses the temporal variation.  The dimensions corresponding to
each pixel of the images for Line (b) are 0.5deg. latitude by 1 day Line (b).  In
the case of Line (c), each pixel corresponds to 0.5deg. longitude by 1 day. 
The text matrix was color-processed with Spyglass R.  Discretely sampled
data, such as that for nutrients, are also processed as temporal-spatial
maps.
	To some extent, in vivo fluorescence from eastbound cruises (Osaka Bay
in the evening and Beppu in the morning)  differed systematically from those
on the westbound cruises (reverse chronology). In vivo fluorescence was
higher in the morning than in the evening (see Fig. 3(b) and (c)).  There are 2
possible causes for this pattern, both related to the circadian rhythm of
phytoplankton.  One is the diurnal cycle of the biomass-specific fluorescence intensity and the other is vertical migration of motile phytoplankton.  Thus the temporal-spatial  resolution achieved in the
present monitoring has the potential to reveal  in situ physiology or dynamics of phytoplankton.  
	  In spite of certain insufficiencies of the Level-2 data, we conclude
that they are quite informative and valuable.  The absolute accuracy of the
Level-2 data will be improved by retrospective correction against data of
point measurements from the usual research vessels.  We will generate
Level-3 data via such processes as the next step.

5. Data files and Directories on these CD-ROM
	 This CD-ROM can be mounted on DOS, UNIX, and Macintosh platforms
provided with ISO9660 compatible CD-Mounters.  A synopsis of the CD-ROM
is shown in README.TXT, which is almost identical to this booklet and
included in the SYNOPSIS-directory.   APPENDIX.TXT contains Appendix 1.
(directory structure),  Appendix 2. (an inventory of the monitoring cruises)
and Appendix 3 ( a list of attended  investigation cruises ).   They are seen
in more orderly form if imported to a word processor with tabsets at every
1 cm and courier fonts of 10points than are read as a raw text.     
	 The FIGURE-directory contains figures such as Figs. 1 and 2.  The
NUMDATA directory contains the subdirectories BTFL94 and  BTFL95, which
contain the DOS-text files from automated filtration sampling. Each
subdirectory, L2Y94M04, ...., L2Y95M12,  contains the Level-2 data for each
month.  Macintosh computer users can transform DOS-text to Mac-text by
changing [CR LF] to [CR] with the TM Apple File Exchange utility.  
	 One record (line) of each bottle and filter data file consists of date+time (date by I6 + L.S.T. by I4), latitude (degree by I2 + minutes by F4.1),
longitude (degree by I3 + minutes by F4.1), filtered water volume (ml),
dissolved nutrients (micro M) (Dissolved-Si, PO4-P, NH4-N, NO2-N, NO2+
NO3-N, and NO3-N), chlorophyll-a (microgram/l), phaeopigments (microgram/l), where I and F refer to integers and floating point values,
respectively.
	The Level-2 Data files for each cruise consist of approximately 4300
and 13000 data records for Lines (b) and (c), respectively.  One record line
corresponds to 1 measurement every 10 seconds and contains the date, local
time, cumulative date from 1900, longitude, latitude,  pH1, salinity (per
mille),  water temperature (deg.), fluorescence (equivalent concentration of
fluoresceine, microgram/l), dissolved oxygen (mg/l), pH2,  error flags for
the H-20 sensors, Turner Design fluorometer, and GPS, respectively.  The
flag value 0 means no trouble. 	  The IMAGE-directory contains the image
files such as those presented in  Fig. 3.   Here, the file name FLU95E (FLU95W) denotes the images of the fluorescence data processed from only
the eastbound (westbound) cruises on Line (b).  In the same manner, the
images processed from data of the southbound (northbound) cruises of Line
(c) have  file names such as FLU94S (FLU94N).  These image files were saved
in GIF (*.GIF) format.  The text matrix generated for processing temporal-
spatial maps is contained in a subdirectory named WSHEET under NUMDATA.

6.Citation and Inquiry
	 The numerical and image data in this CD-ROM should be cited using the
title of this booklet or the report4).  Requests for information or further
shipments of this CD-ROM should be mailed to:
Database Section
Center for Global Environmental Research
NationalInstitute for Environmental Studies 
16-2 Onogawa, Tsukuba, Ibaraki 305, Japan 
	Fax: +81-298-58-2645, E-mail: cgerdb@nies.go.jp
Further inquiries related to technical or scientific problems as well as
errors found by the users should be sent to the editor (harashim@nies.go.jp). 

7.Acknowledgments
	This project owes much of its success to the cooperation of the Kansai
Kisen Co., Ltd.  The project has been implemented by the participants in the
Monitoring Execution Group and Organizations listed below, based on 
discussions of the Committee for East Asian Ferry Monitoring, which has
been organized by NIES-CGER, and the subcommittee's advisory members.

Committee for East Asian Ferry Monitoring:
R. Tsuda (8) ( Chair ), A. Harashima(1)(12), K. Kohata(12), Y. Nojiri(1)(12), K.
Ohta(11) , K. Takano#,  H. Takeoka(3) 
Secretariat Office:
N. Furuta(1), Y. Fujinuma(1), S. Fukuzawa(1), T. Ukigai(1), Y. Yoichi(1), T.
Fukushima(1)	
Monitoring Execution Team:
A. Harashima(1)(12)( Chief ), T. Hagiwara(2), H. Kimoto(7), T. Kimoto(7) (13),
S. Sakamoto(4), Y. Tanaka(8), H. Tatsuta(4), T. Toshiyasu(4), T. Wakabayashi(4)
Advisory members:
H.-D. Ahn(9), K. Imao(10), K. Furusawa(10), Y. Furukawa(5), M. Kunugi(12), Y.
Nakamura(12), J.-R. Oh(9), S. Tanaka(6)
CD-ROM Making Team
A. Harashima(1)(12), Y. Satoh(12),  S. Nakai(1),  T. Miyazaki(1)
Participating Organizations 
NIES-CGER(1), Global Environmental Forum(2), Ehime University(3), JWA
(Japan Weather Association)(4), Kansai Kisen Co., Ltd.(5), Keio University(6),
Kimoto Electric Co., Ltd.(7), Kinki University(8), KORDI (Korea Ocean Research and Development Institute)(9), Marine Biological Research Institute of Japan, Co., Ltd.(10), Nagoya University(11), NIES(12), RIOC
(Research Institute of Oceano-Chemistry)(13) , Professor Emeritus of
University of Tsukuba#.

References
1)Harashima, A. (1993 ): Annual Report on Global Environmental Monitoring
1993, CGER-M003-'93, 33-45.
2)Harashima, A. (1994 ): Monitoring Report on Global Environment 1994,
CGER-M004-'94, 13-50.
3)Harashima, A. (ed.) (1995): Collected data of high temporal-spatial
resolution marine biogeochemical monitoring by Japan-Korea ferry boat  -
June 1991 - February 1993 -, CGER-D007(CD-ROM)-'95.
4)Harashima, A. (1995): Monitoring Report on Global Environment  1995,
CGER-M005-'95,  21-38.
5)Harashima, A., R. Tsuda, Y. Tanaka, T. Kimoto, K. Furusawa  and H. Tatsuta,
(1997):  Mati Kahru ( ed. ) Monitoring Algal Blooms: New Techniques for
Detecting Large-Scale Environmental Change, ( to be published, R. G. Landes
Bioscience Publishers and Academic Press ). 
6)Kimoto, K. and A. Harashima (1993):, Proc. 4th Internat.CO2 Conf. WMO,
Global Atmosphere Watch 89, 88-91.
7)Harashima, A. and Y. Kikuchi, (1990):  EOS, 10, 314-315.

Figure Captions

Fig. 1 Ferry cruise tracks used for monitoring. The previous Japan-Korea
Ferry Program used Line (a).  The present program is being carried out on
Lines (b) and (c).

Fig. 2 Monitoring system deployed on (b) the Osaka-Beppu line (Sunflower 2). 
The system on (c), the Osaka-Okinawa line (Ferry Kuroshio), is similar to
this one.  However, the sea water on Ferry Kuroshio is not from the engine
cooling system but rather from a recently installed valve, unlike that on
Line (b), and no automatic filtration sampling is conducted.  

Fig. 3 Examples of computer generated images of the temporal-spatial
variation of  in vivo fluorescence for 1994 created from Level-2 data from
cruises sailing in both directions ( image files FLU94 on this CD ).  The
vertical axis shows the day number from January 1 to December 31 downward.  The horizontal axis shows the longitude between Beppu (left)
and Osaka (right). 
The images (b) and (c)  were created from westbound cruise only, and
eastbound cruise only, respectively ( image files FLU94W and FLU94E,
respectively, on this CD ).
