Fax: 972 4 8511911
Tel: 972 4 8515202
E-mails: rosen@ocean.org.il and isaac@ocean.org.il
General
The software system ISRAMAR is a package of computer programs integrated in a unified system providing near real-time information regarding meteorological and oceanographic parameters obtained from data gathered using a meteorological monitoring station and an oceanographic monitoring station, transmitted via a modem trough a normal telephone line. At present the software package is operated using an Aanderaa wind station, a Setra atmospheric pressure sensor and a Pacer Systems Inc. (now Woods Hole Instrument Systems) directional wave, current and tide gauge type 10635DWG. The data from the various sensors are transferred via cable to a PC AT 486/DX33 computer, equipped also with a modem and 8 port serial adapter. Options for 6 separate input ports are possible in the present version.
a. The logging, processing and transmission station
The received raw data are logged on the disk. Immediately after sufficient data for statistical and spectral analyses is received , they are processed in real-time by appropriate statistical and spectral analyses programs, included in the package. The resulting values of the representative parameters of the short-term analyses are logged also on the disk. A supervising software module controls via buffering interrupts all data logging and processing, as well as the communication with external users via normal or cellular telephone lines.
At present our station operates as follows: wave bursts of 2048 samples taken 2 times/second are measured from the start of each hour. In parallel, sea-surface pressure samples are taken 128 times per hour by integration of the pressure during each 28.125 seconds (i.e. 3600 seconds divided by 128), continuously around the clock. The wind data and the atmospheric pressure are measured each 5 minutes and averaged every 1 hour. Currents and sea-water temperatures are gathered at a rate of 16 times per hour.
b. The receiving and data presentation station
At the user end a PC-AT 486 computer (equipped with a S-VGA graphic card and appropriate display, a modem, an Epson printer and a hard disk) receives and presents the received data in near real-time. The communication is performed automatically in the background or at request in the foreground, by exiting the main display screen.
Obviously, the communication must be configured according to the modem type and properties. Also the data gathering and logging must be tailored according to the specific equipment used. For equipment different of that used in the present set-up, certain modifications are necessary according to the properties and set- up chosen for monitoring. However such changes can be easily implemented by the developing team according to user specifications.
The main presentation screen shows the values of the data representative parameters both in graphical and tabular format. The processed data are updated on the main screen every 1 to 24 hours with the data gathered and processed until the last hour prior to the update. In this way the MeteOcean (meteorological & marine) information is provided in near real-time. However, due to special modules added to the processing software, it is possible to present at the same time, forecasted astronomic tide values for up to the next 12 hours from the display time, and for certain cases also values of the characteristic and maximum wave height (not included in this demo version).
Description of the windows of the main display screen of ISRAMAR
a. Division of the screen to various information windows.
The screen is divided into two sectors. The upper sector contains four graphic windows, above of which are provided 9 buttons for choice of various options.
The left upper window contains presentation of the time history of the following parameters: characteristic wave height (Hmo), which represents the wave spectral energy, corresponding to what is usually known as the significant wave height, the maximum wave height (Hmax), the peak wave period (Tp) assessed by the Delft method and the zero-crossing wave period Tz assessed via spectral analysis using the Tm0,2 period definition. By choosing a predetermined value of characteristic wave height, it is possible to provide warnings once the most recently measured wave height exceeds the preset value, by changing the wave history window background color to red, or if required, also by sound effects.
The middle left window contains presentation of the time history of the measured sea-level in the last 24 hours and the forecasted sea-level for the next 12 hours due only to astronomic tide (pink color line). In addition in the same window is shown a stick bar time history of the measured current, where the stick length indicates current speed according to a scale bar shown at the left ordinate and the inclination indicates the current direction Azimuth, where North is shown by the arrow of the scale at the left of the left ordinate. The current speed scale is given in m/sec (or at request in knots) on the same left ordinate, and the sea-level scale is shown in meters on the right ordinate of the same window.
The upper right window presents the point power spectrum of the last wave measurement burst, as well as the representative values of the Characteristic wave height Hmo, the Peak period Tpk (determined according to the Delft method) and the Mean wave direction , and above the window are specified the date and time of the measurement. The abscissa represents wave frequency (1/sec) and the ordinate represents the dimensional spectral density (m*m*sec).
Below the upper right window, in the middle right window is shown the last 24 hours time history of the wave spectra measured, allowing a time dependence assessment of the sea state development.
Finally, in the bottom window which extends over the whole screen width are presented in tabular format the values of: the representative parameters of the waves (forecasted characteristic height 3 hours ahead, and measured characteristic height, peak period, average period, mean wave direction and directional spreading, the current (mean current speed and direction) the wind (wind gust, average speed and direction) the measured hourly averaged sea-level, the sea-water temperature and the atmospheric pressure. The data are arranged such that those representing the last monitored hour are given on the top line, and the preceding ones ranked on the next lines below. Each hour the screen is updated with new results and the positions of the data are shifted accordingly.
The buttons at the top of the screen can be accessed via the left or right arrow cursors of the keyboard, and after reaching the wanted button which becomes highlighted, pressing the Enter key on the keyboard.
HELP is used to provide information regarding the various
functions as well as this document
Pg Up is used to move forwards in time in the gathered data
base maintained on the hard disk, updating automatically all
screen windows, one hour each time Enter key is depressed. Of
course one can not progress beyond the last hour of gathered
data.
Pg Dn is used to move backwards in time in the gathered data
base maintained on the hard disk, updating automatically all
screen windows, one hour each time Enter key is depressed.
FIND is used to move to a specific data and time record.
ZOOM is used to zoom the various windows on the whole screen.
To return to the main screen press Esc key
CONFIG is used to define limiting criteria for warning screen
coloring for the wave height, current speed, sea-elevation, wind
speed.
LEGENDS indicates the symbols used for the various parameters
and the lines connecting their data.
UPDATE is used to perform a communication updating or to
access the system for backup or maintenance purposes.
An operational (in MS DOS system) demo of the software
(with disabled data gathering, processing of raw data and
communication of the representative parameters in near-real
time) will be available from approximately 22 April 1996
for downloading from our
Internet site: ISRAMAR@ocean.org.il. User name: ISRAMAR,
Password:User’s own address.