ALBOREX, a major intensive multi-platform and multidisciplinary experiment in the Alboran Sea

Multi-platform ocean observation with, 25 drifters, 2 gliders, 3 argo floats, one ship, 50 scientists and 8 days, these were the headline numbers for ALBOREX, a major intensive multi-platform and multidisciplinary experiment that was completed last week as a part of PERSEUS EU funded project, leaded by CSIC and with strong involvement of SOCIB. This week long experiment was designed to capture the intense but transient vertical motion associated with mesoscale and sub-mesoscale features such as ocean eddies, filaments and fronts, in order to fill gaps in our knowledge connecting physical process to ecosystem response, and so facilitate the sustainable management of our ocean resources and MFSD policy implementation.

The vertical motion associated with mesoscale and sub-mesoscale features such as ocean eddies, filaments and fronts plays a major role in determining ocean productivity, due to the exchange of properties between the surface and the ocean interior. Understanding the relationship between these physical and biological processes is crucial for predicting the marine ecosystems response to changes in the climate system and to sustainable marine resource management. However we have many gaps in our knowledge regarding the links between the physical and the ecosystem, which is particularly true in the Mediterranean where the pressure on marine ecosystems is high, due to the high human population and commercial exploitation.

To capture and understand the links between mesoscale and sub-mesoscale features and ecosystem responses, it is necessary to capture a range of ocean data at a range of temporal and spatial scales, and then combine this data with biological models. This intensive multi-platform and multidisciplinary experiment was part of PERSEUS project and is an example of the new multidisciplinary, multi-platform, integrated and quasi real time approach to Ocean and Coastal Observation. Under PERSEUS, an EU FP7 project in intensive multi-platform and multidisciplinary experiment was undertaken last week in the southern Mediterranean sea, called ALBOREX this project was designed and led by Dr. Ananda Pascual from IMEDEA (CSIC-UIB), who coordinated a team of more than 50 scientists and engineers from many different institutes and countries. 



The ALBOREX experiment started on May 25th, 2014 and fulfilled all its objectives of sampling the intense front where Atlantic and Mediterranean waters meet in the Eastern Alboran Sea. The work has now just started to unravel the three-dimensional structure of oceanic eddies associated with strong density fronts, and will continue in the next months
 

  • Surface salinity samples revealed the frontal location with gradients ranging from 36.6 PSU (Atlantic Waters) to 38.2 PSU (Mediterranean Waters).
  • 25 drifters have followed a massive anticyclonic gyre for a few days and are now along the Algerian current.
  • 2 gliders have worked properly crossing the front (although we had to change in real time the strategy due to extremely strong currents)
  • 3 Argo floats were deployed and transmitting high frequency and interdisciplinary data
  • More than 500 samples (chl and Nutrients) have been collected at 66 CTD stations
  • Near real time data from ADCP showed coherent patterns with currents up to 1m/s (2 knots) in the southern part of the sampled domain.

In the words of Dr. Pascual "the experiment is a success thanks to the efficient and hard work from many scientists and technicians We now face the challenge to analyse, in a cooperative way, a large amount of data and material. This is a process that will take time, but hopefully with the contributions from all of us, we will end up with a good story... "

This experiment was an example of the new multidisciplinary, multi-platform, integrated and quasi real time approach to Ocean and Coastal Observation undertaken within PERSEUS to provide much needed knowledge connecting physical process to ecosystem response and in so doing to facilitate sustainable management of our ocean resources and MFSD policy implementation. The floats and Argo drifters can still be viewed progressing along the North African coast at http://apps.socib.es/dapp