W1-M3A Service Activities


SA Number: 7.1

Name of the SA: W1-M3A SA – Ligurian Sea heat budget and water quality analysis

Institute: National Research Council of Italy (CNR)


W1-M3A products consist of (a) analysis from raw acquired data added in a graphical form and (b) new contents added to the observatory portal. Products are provided open access for 3 years (starting from September 2014). Specifically, the new products delivered within the FixO3 Service Activity, based on near real-time surface meteorological observations, near surface ocean measurements, and bulk flux algorithms are:

  • graphical representations of heat budgets (in terms of Latent heat flux, Sensible heat flux, Net short-wave heat flux, Long-wave heat flux, Evaporation, Wind stress).
  • graphical representations of the near surface water quality (in terms of Dissolved oxygen, chlorophyll-a, turbidity and CO2 concentrations).

The service activity of the W1-M3A observatory provides unique information in near real-time about the climate and the water quality of the Ligurian Sea.

The Ligurian Sea plays a relevant role in driving both the circulation of the Western Mediterranean Sea and weather and climate of the area. It is a deep sea characterized by a narrow continental shelf and mostly bordered by a mountainous coast. It is characterised by a permanent basin-wide cyclonic circulation involving both surface and intermediate waters. This area is not only a transition area for passing cyclones, but it is frequently an area of cyclogenesis. Indeed, a complex interaction is established between the orography of Liguria and the contrast between the cold and humid air mass and the warmer water of the Ligurian Sea. This basin is also important for many biological aspects, its noteworthy high productivity and a rich and complex ecosystem. This leaded to the definition of one of the largest international marine protected area, the so-called ‘‘Cetacean Sanctuary’’.

The service provided can be used for researches in the field of air-sea interaction (i.e., investigation of the atmospheric boundary layer, wind-wave coupling, air pollution transfer modelling, etc.) and oceanography (i.e., water mass transport, biomass migration, marine biogeochemistry, biogeochemical model evaluation and assessment, etc.).

The proposed service can contribute to the following international programs: HyMEX (Hydrological cycle in the Mediterranean EXperiment), ICOS (Integrated Carbon Observation System), GMES (Global Monitoring for Environment and Security), European Multidisciplinary Seafloor and water- column Observatory (EMSO) marine Research Infrastructure, Copernicus Marine Environment Monitoring Service (CMEMS), ESURFMAR – the surface marine observation programme of EUMETNET, etc.


In the following you may find some descriptive text and images for the web site.

Example 1

Exchanges of fluxes of heat, moisture and momentum occur at the ocean – atmosphere interface. The most important heat terms are the sensible heat flux, the latent heat flux, the incoming solar radiation and the balance of long-wave (infrared) radiation. The large heat capacity of the ocean moderates the climate of adjacent areas, leading to a maritime climate at such locations. In the Mediterranean Sea, this results in a heat storage during summer and a release of heat during winter. Latent and sensible heat fluxes products are constructed from the use of the best possible near real- time surface meteorological variables from the W1-M3A observatory, climatic values and best possible bulk flux algorithm (COARE bulk flux algorithm 3.0 from Fairall et al. 2003).

W1-M3A heat fluxes SA picture

Heat fluxes estimated from surface meteorological and oceanographic near real-time
measurements collected by the W1-M3A observatory in the period July-September 2015.

Example 2

Dissolved oxygen into the sea water, concentration of chlorophyll-a and turbidity are some of the measurable parameters that can contribute to assess the good status of health of the ocean.

Dissolved oxygen in the ocean provides a sensitive early warning system for the trends that climate change is causing. Indeed, an adequate supply of dissolved oxygen gas is essential for the survival of aquatic organisms and the amount of dissolved oxygen is directly connected to the type and abundance of organisms that can live. Oxygen enters the water through diffusion from the atmosphere and photosynthesis by aquatic plants, and dissolved oxygen levels are influenced by temperature and salinity (with an inverse proportional relationship).

Calibrated chlorophyll-a concentration is an indicator of phytoplankton abundance and biomass. An understanding of the phytoplankton population and its horizontal and vertical distribution in the ocean can contribute to draw conclusions about the ocean’s health, composition, and ecological status. Turbidity is a measure of the amount of cloudiness or haziness in sea caused by a great variety of scattering particulates (i.e., sediment, plankton, organic by-products).

Turbidity affects the depth that sunlight penetrates in water, thus defining the depth of the photic zone, the zone in which photosynthetic production can potentially occur.

W1-M3A observatory monitors dissolved oxygen, chlorophyll-a and turbidity levels in near real-time with a multi-parametric sensor deployed at 6 m depth. Occasionally, during the periodic maintenance interventions to the observatory, dedicated casts are performed and water samples are taken to get reference measurements to be compared with in-situ values collected by the deployed sensor.

W1-M3A water quality SA picuture

Dissolved oxygen, chlorophyll-a and turbidity measured at 6 m depth at the W1-M3A observatory
in the period July-September 2015. Red dots are the reference values obtained with casts and
water samples collected during the maintenance missions carried out in August 31st and November 13th 2015.


The W1-M3A service activity is organised into two main “one-click links”:

The link http://www.odas.ge.issia.cnr.it/OI1/modules/site_pages/fixo3_service_activity.php display a series of plots (divided into three boxes Heat fluxes, Water Quality, Wind Stress, respectively) produced using data received in near real-time at the ashore station Plots include data of the last 30 days of the following parameters: heat flux, net heat flux, evaporation, dissolved oxygen, chlorophyll-a, turbidity, pCO2, wind stress.
Title for this section is “Heat budget and water quality monitoring through near real-time observations at the W1-M3A observatory”.

The link http://www.odas.ge.issia.cnr.it/OI1/modules/site_pages/download_from_ftp.php provides a web service for downloading both raw data files and plots of heat budget and water quality parameters.
User can choose a year (2013, 2014, 2015, 2016) for getting the data and for visualising plots:

  • In case a past year is selected, data available for downloading are organised on a monthly basis. Plots are organised by months.
  • If current year is selected, data of previous months are available as one file per each month whereas for current month data are available as daily data files. Plots are organised by month.

Data are provided in the netCDF format through the Copernicus Marine Service.

Data and plots can be downloaded locally by clicking on the icons.

Title for this section is “Raw data files and plots download from the W1-M3A observatory”.

Download outputs 

W1-M3A Heat Fluxes SA1.8 MiB
W1-M3A Water Quality SA927.1 KiB