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2010 NASA OCRT Meeting. Louisiana-Texas coastal response during recent hurricanes and an oil spill from ocean color and model results. Eurico D’Sa Dong-Shan Ko*, Mitsuko Korobkin, Nan Walker Dept. of Oceanography and Coastal Sciences Louisiana State University

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Louisiana-Texas coastal response during recent hurricanes and an oil spill from ocean color and model results

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Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

2010 NASA OCRT Meeting

Louisiana-Texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Eurico D’Sa

Dong-Shan Ko*, Mitsuko Korobkin, Nan Walker

Dept. of Oceanography and Coastal Sciences

Louisiana State University

*Naval Research Laboratory, Stennis Space Center

Thanks: NASA Ocean Color Data Processing Team

Funding: NASA

MMS


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

  • Science Question

  • How do hazards and pollutants impact the hydrography and biology of the coastal zone? How do they affect us and can we mitigate their effects?

  • Background

  • Mississippi River ranks 2nd globally in terms of drainage basin and river discharge

  • Discharge from the Mississippi-Atchafalaya River strongly

  • influences biogeochemical properties of the northern Gulf of Mexico

NOAA -CSCOR


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

  • Background

  • Economic importance

  • oil & gas

  • ~1/3 of US fisheries yield

  • Major issues

    • Eutrophication and hypoxia

    • Hurricanes and storms

    • And now a major oil spill


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

  • Outline

  • Methods and data

  • Ocean color and model results

  • Two major hurricanes in 2008

    • Hurricane Gustav- 1 Sep

    • Hurricane Ike – 13 Sep

  • Deepwater Horizon- oil spill

    • Short-term monitoring using MODIS and model results


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Gulf Coast Information System

http://gulf-coast.lsu.edu

  • Components:

    • Field data

      • Used WAVCIS platform-based

      • measurements for model validation

      • NOAA tide station data

    • Remote Sensing

      • Ocean color products from

      • MODIS and SeaWIFS

      • SST from MODIS

      • winds from QuikSCAT

    • 3-D NCOM Model

      • Sea level, Currents

      • SST, SSS

      • Horizontal resolution: ~1.9 km


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Satellite data

Suspended Particulate Matter (SPM) algorithm for SeaWiFS

  • SeaWiFS

    • Chl – OC4

    • SPM algorithm

SPM = 17.783 (Rrs670/Rrs555)1.11

  • MODIS

    • SST

    • Chl

    • 250 m

  • QuikSCAT

    • Wind speed

    • Direction

D’Sa, Miller & Del Castillo 2007

Geophysical Research Letters


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Intra-Americas Seas model

(GOM, Caribbean, part of western North Atlantic Ocean)

Nested MsLaTex Coastal Model

NRL Coastal model nested within the the larger IntraAmericas Sea Model

  • Longitude : 95.5 W – 88.2 W; Latitude : 27.0 N – 30.5 N

  • Horizontal Resolution : 1/64 Degree (~ 1.9 Km)

  • Vertical Resolution : 36 Layers (19 Layers on the shelf)

  • Number of Grids : 372 x 200


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Short-term

SPM -fronts

NCOM- model simulation of sea level & currents

3/23/05

3/28/05

Wind forcing effects on: sea level, currents and SPM

D’Sa and Ko, Sensors 2008


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Hurricane studies

  • SST and ocean color have been

  • used to study effects of

  • hurricanes

  • A common observation has

  • been a decrease in SST and

  • Chl blooms associated with

  • hurricane passage

(Babin et al. 2004; Walker et al. 2005)

  • Sediment resuspension events have been detected in NGOM from

  • ocean color during Hurricanes Dennis and Rita in 2005

  • (Hu and Muller-Karger 2006; Lohrenz et al. 2008)


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Hurricanes – physical processes

  • Turbulent mixing and a coastally trapped barotropic Kelvin

  • wave was also detected and modeled during Hurricane Andrew

  • in 1992 (Keen and Glenn 1999; Keen and Allen JGR 2000)

  • We examine the above physical processes detected using the

  • MsLaTex3-D model and its effects on the coastal ocean using

  • satellite remote sensing data

  • Hurricane Gustav – turbulent mixing

  • Hurricane Ike – coastally trapped wave


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Coastal response to Hurricane Ike

D’Sa, Korobkin and Ko 2010 – Remote Sensing Letters – in press


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Hurricane Ike effect on SST

Avg 5-day (6-10 Sep 2008)

Avg 5-day (14-18 Sep 2008)


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Mean Sea Level (tide stations)

vs

and Sea Surface Height (model)


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Hurricane Ike – coastally trapped barotropic Kelvin wave

NCOM SSH on 11 Sep, 1200 UTC

NCOM SSH on 12 Sep, 0600 UTC

More than one maxima and reported earlier than expected surge appears to be due to a coastally trapped wave

CTW is a rapidly moving disturbance that takes the form of a wave field and travels along the coastline

CTW form as hurricane winds force the ocean water against the coast and create a bulge of high sea level

CTW have been shown to amplify the storm surge (Morey et al 2006)


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Hurricane Ike – coastally trapped barotropic Kelvin wave

Time-distance plot of SSH simulated by NCOM along 28.5°N lat. suggests the appearance of a large wave at the Mississippi Canyon (~90W longitude) on Sept 12.

It traveled from 90-95° W in ~ 8 hrs => speed 17 m s-1.

Assuming H = 30m

Speed of CTW

√gH = 17 ms-1

Hypothesis:

Forerunner wave

Sediment

resuspension


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Hurricane Ike

Effects on coastal SPM

  • SPM from SeaWiFS

  • for 17, 25, 27, 30 Sep

  • Two wind events 15, 21

  • Discharge of inundated

  • waters

  • Plumes of elevated SPM

  • River discharge

  • increased by 12% (25-

  • 29 Sept)


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Oil Spill in the Gulf of Mexico

April 20 explosion at the Deepwater Horizon rig

Modis 250 m res imagery has been most useful

Many sources – : NASA MODIS web-rapid response project

NCOM SSH on 11 Sep, 1200 utc

MODIS Terra – 29 April

MODIS Terra – 4 May

Hu et al. 2003 and 2008 - used MODIS 250 for detecting oil in surface waters


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

MODIS Terra – 29 April: True color

MODIS Chl

(Aqua)

MODIS Rrs(412)

(Aqua)


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

MODIS adg(412)

(QAA)

29 April 2008


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

MODIS DB – Near real time imagery

LSU Earth Scan Lab – esl.lsu.edu

MODIS Aqua - 25 Apr

18:50 UTC

MODIS Terra - 29 Apr

16:48 UTC

MODIS Terra - 1 May

16:48 UTC

MODIS Terra - 8 May

16:48 UTC

MODIS Aqua - 9 May

16:48 UTC


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Gulf of Mexico Oil Spill

MODIS Terra - 29 Apr

band 2 -856 nm

Converted to model grid using optimal interpolation

Surface velocity distribution


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Gulf oil spill – effects on ocean color products

  • MODIS 250 m after accounting for sun glint and cloud could

  • be assimilated into numerical models for spill trajectory

  • analysis

  • Reflectance characteristics different for MODIS Aqua and

  • Terra

  • Different effects of oil slick and sheen on reflectance data

  • Need to account for changing nature of the oil in surface

  • waters due to degradation; also surface vs subsurface

  • Hyperspectral sensors (AVIRIS, HySpiri, GEO-CAPE)

  • baseline optical data would be very useful in characterizing

  • changes


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Conclusions

  • Coastal response to hurricanes not clear from remote sensing

  • or numerical models alone

  • combining satellite and model data provided considerable

  • insights into interaction of physical (turbulent mixing and

  • coastally trapped waves) and biogeochemical processes

  • MODIS 250 m data proving to be most useful for oil spill

  • monitoring

  • Need for timely field data to characterize ocean color data

  • related to oil spill


Louisiana texas coastal response during recent hurricanes and an oil spill from ocean color and model results

Thank You


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