As far as onboard measurements are concerned, the earliest accessible data on vertical profiles of temperature and salinity go back to 1950s when oceanographic stations were carried out in the Gulf of Oman by the Japanese research vessel "Umitaka Maru". Since that time and up to 1992, Japan has deployed a series of expeditions with 1100 oceanographic stations carried out in the Gulf of Oman region.
In 1966, 24 hydrographic stations were conducted by Russian R/V "Mikhail Lomonosov". Later on, Indian R/V "Darshak" (1974) and Norwegian R/V "Dr. Fridtjof Nansen" (1975) continued hydrographic measurements in the region.
From 1980 through 1997, a number of stations were carried out by Russian, American, German, British, and Pakistani research vessels. The latest comprehensive survey of the Arabian Gulf was undertaken in 2006 by the ROPME program, with over 100 oceanographic stations over the Arabian Gulf, of which 29 were situated in the Sea of Oman (http://www.ropme.com/program2.html).
At the present time, the project inventory assembled contains information on 90 datasets since 1950 through 2010 (with 16,000 hydrological casts). Examples of spatial coverage are given in the Figure 1:
Figure 1. Oceanographic stations carried out by research vessells in 1950-2010.
As far as the ARGO profiles are concerned, ARGO is a global array of 3,000 free-drifting profiling floats measuring the temperature and salinity of the upper 2000 m of the ocean. The coordinate space used for the project is 10oN- 26oN, 57oE - 62oE. Time range : 16/03/2002- 01/05/2010', with 2,352 observations of ARGO profiles.
Historical data (Figure 1) were retrieved from archives and databases of the following institutes :
- Marine Hydrophysical Institute (MHI), Ukraine
- Institute of Biology of Southern Seas (IBSS), Ukraine
- Sultan Qaboos University (SQU),Sultanate of Oman
- British Oceanographic Data Centre (BODC), United Kingdom
- National Oceanographic Data Center (NODC), USA
- The Institute for Marine research (IfM), Germany
- Royal Netherlands Institute for Sea Research, The Netherlands
- National Institute of Oceanography, Pakistan
- Japan Oceanographic Data Center , Japan
Historical data on measurements on board, were complemented by data on fish kill incidents along the Omani coast, available from the archives of the Marine Science Research Center (Muscat, Oman). The earliest records were dated by mid 70s.
Data on fish stocks were taken from the annual reports published by the Ministry of Fisheries of Oman (Fishery Statistics Book, 2009).
Along with historical data assembly, coastal sampling was carried out by the Sultan Qaboos University (Dep. Marine Science and Fisheries), in 2004-2011. Monthly CTD casts, phytoplankton and zooplankton samples were collected in the Sea of Oman and processed to the species level.