ANCHOR Synergies with Global-scale efforts Bruce M. Howe Acoustic Navigation and Communication for High-latitude Ocean Research (ANCHOR) Workshop Applied Physics Laboratory, University of Washington, 27 February – 1 March 2006

Outline of Talk A little history and background ASA Integrated Acoustics Systems for Ocean Observatories GPS ORION status ORION acoustics Connection to ANCHOR

History Sun, moon, stars, terrain/feature tracking Compass, sextant and variants Time – longitude Time standards – 1930s Einstein’s predictions of effect of gravity on time. Nobel Prizes: Rabi 1944 atomic resonance; Ramsey 1989 hydrogen masers Radio, loran, mini-ranger, … Satellites –Sputnik – Doppler navigation –Transit satellites 1965 (a few fixes/day, 15 min integration) for Polaris subs –GPS – one Sept weekend, 1973, full coverage time and space Deep space network – nav and comms -> deep space internet, infrastructure around Mars, occultations Underwater – SOSUS, Navy ranges, LBL, FLBL, Swallow/SOFAR/RAFOS/mobile/tomography

Acoustics in Ocean Observatories Acoustic methods will be ubiquitous in ocean observing –Ocean is transparent to sound, but largely opaque to electromagnetic radiation –Provides synoptic, volumetric sampling Cross cuts across many disciplines – opportunities for synergies and integration

Integrated Acoustics Systems for Ocean Observatories (IASOO) Science Communication Navigation Unified architecture across all scales ASA-AO committee 2003

IASOO Concepts Acoustic sources act as “GPS satellites” underwater to provide signals for –Navigation –Communication –Science Receivers on all platforms Simultaneously –Ambient sound (wind, rain, seismic, whales, shipping, …) –Tomography –Others 2-way communications as appropriate Manage the acoustic spectrum – all users Unified architecture across all scales

ORION Workshop ice Jan 2004 Puerto Rico Recognized as part of observing system

Projection slice theorem Norton: – if sensors only on periphery, only get vorticity, not divergence

Global Navigation Satellite Systems GPS Glonass Galileo –90 sources in space

GEONET Japanese Meteorological Agency, 2003 Maps of Precipitable Water (PW)

GPS Experience Huge user base has evolved >3000 science receivers – international data centers GPS Navigation message –50 b/s, 20% parity bits, 1 of 10 words for sync, 30 s –Clock correction –Ephemeris (orbits/position/velocity) –Ionospheric correction parameters –UTC information –Almanac Differential measurements, WAAS, quality, …

Back to the ocean

Major NSF Ocean Sciences Program started 2004 Infrastructure MRE funds $309M in FY2007!!! PLUS all science, O&M, DMAS, E&O, … 30 years

Elements Sustained presence – research and operations – power and comms (x,t) Three Components –Regional, cabled + –Coastal, cabled, moor, + –Global, Moorings NSF ORION IOOS

Distributed sensor system Navy example Environmental assessment defines cluster topology and fixed/mobile mix Fixed and mobile sensor nodes deployed for optimum coverage. AUV’s enter semi- dormant state as temporarily fixed or drifting nodes Reconfigure mobile sensor nodes based on current environmental situation Event detection communicated to network (ACOMMS or RF) Mobile platforms respond

NEPTUNE – in progress NEPTUNE Canada Install summer nodes, to Endeavor Loop design CDN$40M With Alcatel Test beds MARS and VENUS Mid-2006 Late 2005

ORION RFA concept proposals 5 major acoustic, 12 others, 17 acoustic out of 48 total – ORION recognizes acoustic components Worcester et al.: Thermometry, support navigation, ambient sound, t-phase Duda et al.: float tracking (process studies) and thermometry Detrick et al: geophysical, called for bottom/sofar hydrophone, Stephen et al – sofar t-phase Daly et al., Barth et al.,: NEPTUNE/coastal multipurpose mooring array, tomography Horne/fish/mammals Bioacoustics observatory/hawaii 3 ambient sound (1 with CO2) Small scale tomo/vents Many with gliders and AUVs with navigation implied

Daly et al. Water column oceanogra phy

Worcester et al Thermometry Also navigation

Duda et al Precise float tracking Dispersion Meridional overturning Thermometry

Alternate Source Test (AST) 28 and 84 Hz Simultaneous signals, phase locked (3 rd harmonic) Source from DP ship, DGPS Deployed in deep water near Pioneer Seamount, 1995

Main Points Applicable to all cases: –Timing is fundamental –Navigation implies communications –Tomography results (sound speed and velocity) –All signal compatible –Ambient noise – spectrum, marine animals –GPS is a good analogy –Work to inexpensive receiver –Modeling and data assimilation crucial – start/continue now –Equipment needs (Arctic and lower latitudes) are similar Arctic Data N ~ S x R, say S = 5(6) –Fixed N = (5 x 4) / 2 = 10 (15) –Add 16 tethered (x,t known), add N = 5 x 16 = 80 (96) –Add 32 mobile (x,t unknown), add N = (5-3) x 32 = 64 (96) –Total – 154 (207) independent ocean samples each ping

Path Need roadmap More funding! Next MREs, other, … Expect 10 years for big chunks – BUT play up short, critical time frame