Marine Physics

Marine Physics and Numerical Modelling Research Group focuses on the observational and modelled aspects of the water column structure and circulation dynamics of Qatari waters within the context of the larger Arabian Gulf marine environment. Ongoing research of the group involves the study of the hydrography and circulation within Qatar's exclusive economic zone (EEZ) and the seasonal and interannual variability in the distribution and transformation of water masses. Hydrographical data (temperature, salinity, optical and chemical properties, and current profiles) are collected and analyzed to investigate the influence of oceanic and atmospheric forcing at various spatial and temporal scales within Qatar's marine area. Numerical modelling is performed to complement observational studies for a more comprehensive understanding of the coupled marine-atmosphere-ecosystem, sediment and particle dynamics and to predict the future state of the marine environment as impacted by natural and anthropogenic stressors.

The research group uses shipboard, portable, and moored instrumentation to collect hydrographical data and perform current measurements. Data analysis, management and visualization is performed using state-of-the-art software and computer programming. Numerical modelling studies are carried out using high-performance computing clusters. Besides own research, the group also provides technical and scientific support for hydrographic data acquisition and analysis to other ESC, QU, and national & international research teams and projects.

Physical Oceanography and Numerical Modelling Laboratory The laboratory features state-of-the-art sensors and transducers to collect hydrographical data along the water column and high-performance computational hardware to analyze, manage & visualize oceanographic data as well as to perform numerical modelling of coupled ocean-atmosphere-ecosystem dynamics.

Instrumentation and oceanographic data collection

Water column data acquisition:

• CTD (Conductivity-Temperature-Depth) System: The CTD systems onboard RV JANAN consist of a SeaBird SBE-911plus CTD attached to a SeaBird SBE-32 Carousel Water Sampler and a stand-alone SeaBird SBE-25 CTD. SBE-911plus and SBE-25 also feature auxiliary sensors for measuring

1. 1. optical properties (fluorescence, turbidity, photosynthetically available radiation [PAR], light transmission-attenuation-scattering),
   2. chemical properties (pH, dissolved oxygen).

• Thermosalinograph: SeaBird SBE-21 SeaCAT thermosalinograph onboard RV JANAN is used for continuous underway measurement of sea surface temperature and salinity.

Current measurements:

• Moving-vessel current profiling: Teledyne RDI Ocean Surveyor OS-150kHz Acoustic Doppler Current Profiler (ADCP) hull-mounted on the RV JANAN and Teledyne RDI Workhorse Sentinel 600kHz
• Moored current measurements: Moored ADCPs (Teledyne RDI Sentinel V50 500kHz and Nortek Aquadopp Z-cell 1MHz) and current meters (Aanderaa SeaGuard RCM) are used to collect point and profile current data.
• Navigational and atmospheric data: Navigational and atmospheric underway data are collected using RV JANAN's navigational equipment and the onboard meteorological station.

Data Analysis, Management and Visualization

State-of-the-art computer hardware, software and own programming is utilized to implement oceanographic databases and to analyze and visualize oceanographic data.

Numerical Modelling

A high-end desktop server (Apple Mac Pro 12-core) and the QU high-performance computing (HPC) clusters are utilized to implement high-performance numerical models of coupled marine-atmosphere-ecosystem, sediment and particle dynamics, capable of producing hindcasts, nowcasts, and forecast simulations of Qatar's marine dynamics.