Ocean Observation, Climate Change and Disaster Warning:
the Context
David MeldrumConsultant, IOC/UNESCO, Paris
Contents of presentation
• Is climate changing?• Ocean observing systems already in place
– Weather and climate– Disaster warning
• The challenges of the deep ocean• Opportunities for cable operators to make a difference
The evidence for climate change: global temperatures
The evidence for climate change: global sea level
Sea level rise: observed regional trends
Sea level rise: population vulnerability
The evidence for climate change: Arctic sea ice extent
Timescales of climate variability and the ocean
The evidence for climate change: deep ocean temperatures
GOOS: the Global Ocean Observing System
Examples of the instruments used
Moored instruments
Challenges of the deep ocean (compared to space)
• Satellites can’t see below the sea surface• Instruments have to withstand high pressure and corrosion• No energy source (e.g. solar panels)• Difficult for communications and imaging
But it’s only skin deep!
Unusual deep seabed features?
No – they came from the red planet, not the blue planet!
Techniques for observing the deep ocean
• Moorings• Landers• Lowered instruments• Acoustics• Cabled observatories• New oceanographers!
Disaster warning - tsunamis
Tsunami warning networks
Seismic activity
Not all seismic activity causes tsunamis
Japanese tsunami: predictions and observations
itic.ioc-unesco.org
Analysis centres generate warnings
Vandalism is a major problem
Cables offer a solution
• Vandal-proof in the deep ocean• Instantaneous communications• Energy source• Next generation commercial repeaters to include built-in
tsunami sensors?• Why not other sensors as well?
– Ocean properties such as temperature and salinity– Seismometry– Passive acoustics
Passive acoustics has been used from cables before
Blue whale migrations using SOSUS
Ocean acoustic pollution is a major issue
IOC, Paris, Sept 2011
Conclusions
• The deep ocean is poorly observed• Next generation cable repeaters could make a major impact• Important climate variables could be measured• Acoustic sensors would cast new light on marine mammals• Cables offer the ideal solution for tsunami warning
– Vandal resistant– Instant communications– Energy available– Could be a business opportunity– Or why not just be green and eco-friendly and improve your image!
• Suggestion: establish a small enthusiastic group to sketch out a limited pilot project
Cables are the future!
TAT-1, Oban, Scotland
Thank you!