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Explore the distribution of bioluminescence in the Mediterranean Sea, its impact on neutrino telescope sites, and modeling the frequency of bioluminescent flashes. Discover sources of bioluminescence from animals and bacteria and the measurement methods used. Gain insights into the variability of bioluminescent sources across different plankton sizes and depths. The study combines field data from four cruises to map bioluminescent distributions and predict effects on a neutrino telescope array.
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Distribution of bioluminescence in the Mediterranean Sea and predicted effects on a neutrino telescope Jessica Craig, Alan Jamieson, Amy Heger, Alain Zuur & Monty Priede Oceanlab, University of Aberdeen, Scotland, UK www.oceanlab.abdn.ac.uk
Talk outline • Bioluminescent sources (BL) • Measurement methods • BL Distribution in the Mediterranean Sea • BL Distribution at neutrino telescope sites • Modelling the frequency of BL • BL around the PMT optical module
Bioluminescent sources • ANIMALS - Non steady-state flashes • BACTERIA - Steady baseline source of light • Centred on 480nm • Mesoplankton – 0.2-20 mm • (e.g. copepods) • Macroplankton – 20-200 mm • (e.g. euphausiids) • Megaplankton – 200-2000 mm • (e.g. medusae & large colonial • organisms (e.g. pyrosomes)) • (Dussart et al. 1965, Sieburth et al. 1978)
Bioluminescent sources • Quantum emission (photons.flash-1) • Mechanical, chemical and visual stimulation (Heger 2007)
Measurement method • ISIT profiler • ISIT camera – 5 x 10-6 lux (min faceplate sens.) • ‘Splat screen’ – 500 x 375 mm A B C D A – Ultra-low-light camera B – Power/control unit C – Lamp D – Splat-screen (Priede et al. 2006, Heger et al. 2008)
Mediterranean BL distribution • Sampling stations from 4 cruises • ANTARES • - Jan 2004 • ANTARES • - May 2004 • RV Meteor 60-1 • October 2006 • NESTOR • RV Aegeao • - May 2007
Mediterranean BL distribution • Sampling stations from 4 cruises • ANTARES • - Jan 2004 • ANTARES • - May 2004 • RV Meteor 60-1 • October 2006 • NESTOR • RV Aegeao • - May 2007
Mediterranean BL distribution • Sampling stations from 4 cruises ANTARES - Jan 2004 ANTARES - May 2004 RV Meteor 60-1 - October 2006 NESTOR RV Aegeao - May 2007
Mediterranean BL distribution • Sampling stations from 4 cruises • ANTARES • - Jan 2004 • ANTARES • - May 2004 • RV Meteor 60-1 • October 2006 • NESTOR • RV Aegeao • - May 2007
Mediterranean BL distribution • Sampling stations from 4 cruises ANTARES - Jan 2004 ANTARES - May 2004 RV Meteor 60-1 - October 2006 NESTOR RV Aegeao - May 2007
Mediterranean Sea productivity • High surface productivity High abundance bioluminescent sources January April July October MODIS monthly composites Chlorophyll a (2006) (Ocean Colour Portal: http://marine.jrc.cec.eu.int)
Near seafloor BL density • Near-bottom BL density decreases with increasing seafloor depth BL density (sources.m-3) R2 = 0.92 NEMO site not yet sampled Seafloor depth (m) At seafloor depth of 3500m Estimate: 0.05 sources.m-3
Modelling BL frequency • Impacts on detector • Background • Predicted number of bioluminescent flashes in vicinity of OM (Priede et al. submitted; Heger 2007; Buskey & Swift 1990)
BL around the PMT module (Latz et al. 1987; Bowlby & Case 1991)
BL around the PMT module (Latz et al. 1987; Bowlby & Case 1991; Bowlby et al. 1990)
Summary • Low surface productivity Low BL density • Deeper site Low BL density More detailed info: Priede et al. (submitted) The potential influence of bioluminescence from marine animals on a deep sea underwater neutrino telescope array in the Mediterranean Sea. DSR I.
Thanks to: John Carr, the ANTARES collaboration and crew of the GGIX fast catamaran Andre Freiwald, (University of Erlangen) and crew of the FS Meteor (cruise M70 leg-1) Spyros Stavrakakis (HCMR) and crew of the RV Aegaeo UK Natural Environment Research Council Luxembourgish Ministry of Culture Thank you!