Ocean and Acoustic Modeling and Predictions Adaptive Sampling Recommendations PLUSNet Hot Wash-up Presentation MBARI, Aug 26, 2006

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Ocean and Acoustic Modeling and
PredictionsAdaptive Sampling RecommendationsPL
USNet Hot Wash-up PresentationMBARI, Aug 26, 2006
HARVARD - MIT Modeling, Predictions and Adaptive
Sampling Team
Pierre Lermusiaux, Patrick Haley, Ding Wang
(MIT), Wayne Leslie and Oleg Logutov
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Daily Environmental Prediction Undersea
Weather Major Accomplishment I
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Measured and Estimated Sound Speed Radial 4
Measured and Estimated Averaged Currents 0-200m
OPAREA Bathymetry and Analysis Radials
Surface SSP and Currents
100m Depth SSP and Currents
30m Depth SSP and Currents
See http//ocean.deas.harvard.edu/PLUSNet for
twice daily plots and hourly data files
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Daily Acoustic-Environment Predictions e.g Aug
23 4PM Local Time (Aug 24 00Z) Major
Accomplishment II
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Forecast Surface Currents (used by PLUSNet assets
for planning drifting missions)
OPAREA Bathymetry and Analysis Radials
Surface SSP and Currents
Transmission Loss Prediction (issued on Aug 22
12Z) Along Radial 6, for a source at 5m and a
receiver at 15, 45 and 75m
Sound Speed Radial 6
See http//ocean.deas.harvard.edu/PLUSNet for
twice daily plots and hourly data files
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Example of Daily Summary Description Emails

• Environmental and acoustic nowcasts and
  predictions up to 00Z Aug 26 are available from
  http//oceans.deas.harvard.edu/PLUSNet
• http//oceans.deas.harvard.edu/PLUSNet/Aug25/plusn
  et_product.html
• Product files are in http//oceans.deas.harvard.e
  du/PLUSNet/Products
• Upwelling event is ending and our forecasts
  indicate that relaxation conditions (warmer
  surface temperatures and no wind-driven currents)
  will start tomorrow. See for example tomorrow's
  afternoon surface sound speed and current
  vectors http//oceans.deas.harvard.edu/PLUSNet/Au
  g25/PN/Forecast/ssp000_aug27_fcst_00Z_PN.gif
• Based on our studies of the past week of
  transmission loss estimates, relaxation
  conditions correspond to -more- mean loss at
  100Hz and 400Hz than upwelling conditions. The
  average difference at 100-400Hz and at 10km range
  is about 3 to 8db more mean loss. It would be
  very interesting to find out if the measured mean
  acoustic performance (TL)at these frequencies
  over 7 to 15km ranges is lower tomorrow afternoon
  than it has been in the past days of upwelling
  conditions.
• Vertically averaged current velocities in the
  PLUSNet ops area are expected to be to the
  northwest, following the coastline. For example,
  for tomorrow morning http//oceans.deas.harvard.e
  du/PLUSNet/Aug25/PN/Forecast/vave_PN_aug26_fcst_12
  Z.gif
• Surface velocities are expected to be patchy.
  For drifting behaviors, we recommend to combine
  it with a vertical yoyo so as to be drifting in
  vertically averaged currents, which are forecast
  to the northwest.
• Transmission loss predictions available from
  http//oceans.deas.harvard.edu/PLUSNet/Prolog/Aug2
  5/index.html

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Effects of the predictable ocean environment on
acoustic TL predictions
Relaxation B6 D3 8_25_06
Upwelling B6 D1 8_22_06
Relaxation conditions (warmer surface
temperatures and no wind-driven currents)
correspond to more mean loss at 100Hz and 400Hz
than upwelling conditions 3 to 8db more mean
loss over 7 to 15km.
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Example of AREA mission C2 Adaptive Yoyo Major
Accomplishment III
8/22/06 Starting point lat36.9414,
long-122.2232 1. Bearing180 degree clockwise
from the north, waypoints are r 0 1 2
3 4 5 6 7 8 9 10
km z 0 50 75.0000 75.0000 100.0000
50.0000 0 50.0000 0 50.0000 100.0000
m 2. Bearing180 degree clockwise from the
north, max range10km, optimal yoyo control
parameters are(10, 0.5) XXX.Initialize(5, 100,
0, 10, 0.5)//upper bound 5m lower bound 100m
initial depth 0m points10 threshold 0.5. 3.
Bearing180 degree clockwise from the north
ADPltdoublegt DW_ADP DW_ADP.Initialize()
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A priori Mean TL std
Posteriori Mean TL std
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Example of AREA mission C4 Front Tracking Major
Accomplishment III
8/23/06 In the morning1. run predetermined
path Waypoints are (lat36.916774452289long-12
2.190015784337), (36.959751554578 
-122.262152715663),(36.966729966627,
-122.255703125301),(36.923748958313 ,
-122.183563374699),depth0m2. or run this
Starting point lat 36.916774452289  ,
long-122.190015784337, depth0m. 
DingWang_2D_Gradientltdoublegt DW_Gradient 
DW_Gradient.Initialize(270., -1)//the initial
AUV direction is 270 degreeclockwise from the
north -1 follow the opposite gradient
directionlet AUV hit the northwest side of
PLUSNet box, and then directly come back.In the
afternoon3. Waypoints are (36.927933661928 
-122.179691928916), (36.970917013855,-122.2518333
71084), (36.977895425904,  -122.245383780723),
(36.934908167952-122.173239519277),
depth0m.4. Starting point lat
36.927933661928  , long -122.179691928916,
depth0m.DingWang_2D_Gradientltdoublegt
DW_Gradient  DW_Gradient.Initialize(306.663991.,
-1)//the initial AUV direction is 306degree
clockwise from the north -1 follow the opposite
gradient directionlet AUV hit the northwest side
of PLUSNet box, and then directly come back.
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8_24_06 Morning
8_24_06 Afternoon
8_24_06 Morning
8_24_06 Afternoon
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Significant Lessons learned And Data Needs

• Feedback during the telecon was essential
• Enjoyed feedback very much. Thank you PLUSNet
  team!!
• Next time, we could create a coop plusnet
  web-page where such feedback can be posted
• Data that you have and data that you need
• Have substantial measured T,S data and
  data-driven model estimates
• Need More plots or Quantitative evidence to
  support successful or failed usage of our
  estimates, e.g
• Marc Stewarts email based on our SE currents
  predictions in S corner of domain Pierre,
  You'll be interested to know that our Restech
  reported substantial SE surface current in the S
  corner of the PLUSNet box today as she attempted
  to recover a Bluefin in an Avon. I personally
  doubted it, but now I know better! Thanks, Marc