1. INTRODUCTION

Meteorology and Oceanography (METOC)professionals of the U.S. Navy and Marine Corpsface a daunting task: characterize the operatingenvironment globally, and more specifically, in thevast oceans and littoral regions, to enhance thesafety and efficacy of forces. However, thisoperating environment is typically the verydefinition of “data sparse”. Remote Sensing fromsatellites has become an integral part of Navaloperational analysis and forecasting. This hasbeen accomplished though extensive and focusedresearch and operational transition efforts, bothNavy-sponsored and leveraged from the scientificcommunity at large. This paper offers an overview of currentsatellite usage and those research areas whichhold the promise of transition to operations in thenear term. Technologies include passivemicrowave, visual and infrared imagingapplications, multispectral applications,scatterometry, altimetry, SAR and feature analysisfrom high-resolution commercial imagery.Applications of these technologies to real-worldNaval operations are detailed.

2. VIS/IR APPLICATIONS

Like all of those charged with operationalmeteorology, visible and infrared imagery remainprimary tools in weather analysis and forecasting.We therefore share the common requirements ofincreased spatial resolution and refresh for thistype of data from both geostationary and polar-

orbiting platforms. The VIS/IR data are also used extensively inmore quantitative ways. The NavalOceanographic Office (NAVO) produces SeaSurface Temperature analyses from multi-channelIR sensors using the 11-12 micron split-windowtechnique for operational Navy usage and forgeneral use under the auspices of the SharedProcessing Program (SPP) (Rigney et al., 1997). Geostationary VIS/IR and water vapor channelsare used to derive high-density feature-trackedwinds for use in Numerical Weather Prediction(NWP) models run at Fleet Numerical Meteorologyand Oceanography Center (FNMOC) in Monterey,CA (Figure 1). This operational capability is theculmination of a collaborative research effortbetween the Naval Research Laboratory (NRL)Monterey and U. of Wisconsin/CIMMS (Velden etal., 1997). Expansion of this program is underwayto include data from the Japan MeteorologicalAgency GMS and EUMETSAT Meteosatprocessed by another SPP partner, the Air ForceWeather Agency (AFWA) in Omaha, NE withFNMOC background fields. Data from IR Sounders are also importantinputs to NWP efforts. Through SPP, the Navyleverages NESDIS expertise in soundings, usingthe NESDIS-supplied POES soundings deliveredvia SPP communications operationally. Inaddition, research is progressing on directradiance assimilation into Navy numerical models. Recent transitions into operational usageinclude a low cloud product using a bispectral IRtechnique, which gives forecasters a nighttimecapability for fog/stratus determination. A newcapability to stitch together multiple geostationarydata has also been developed, offering militaryplanners with global purview (and the METOCprofessionals supporting them) a virtuallyseamless global satellite depiction. Thesecapabilities were part of a Cooperative Researchand Development Agreement (CRADA) betweenNRL Monterey and SeaSpace, Inc. described inHawkins, et al., 2000.

SATELLITE DATA UTILIZATION BY U.S. NAVY METEOROLOGY AND OCEANOGRAPHY

Don T. Conlee and Richard L. Crout*

Naval Meteorology and Oceanography Command Stennis Space Center, MS 39529

3.5

Corresponding author address: Dr. Richard L.Crout, N543, COMNAVMETOCCOM, 1100 BalchBlvd., Stennis Space Center, MS 29529-5005;email: croutr@cnmoc.navy.milOnline paper link: https://www.cnmoc.navy.mil/nmosw/handbk.htm#articles

FIG. 1. High density feature tracked winds product. The typhoon near 28N, 140E is Kong-Rey (9W).

3. PASSIVE MICROWAVE

Exploitation of passive microwave imagery,particularly that from the Special SensorMicrowave Imager (SSM/I), has long been aprimary emphasis of Navy remote sensing. Thepassive microwave ability to sense surface windspeed over the vast data-sparse oceans isfundamental to Navy METOC efforts to assess andpredict high winds and seas. FNMOC is the SPPCore Processing Center (CPC) for passivemicrowave imagery, providing the parameters ofwind speed, rain rate, integrated water vapor,cloud water content, soil moisture and iceconcentration for SPP and operational Navy usage(Cornelius, et al., 2000). The algorithms for theseparameters are those approved by the SPPAlgorithm Research Panel (ARP) process, co-chaired by FNMOC and the Naval ResearchLaboratory (Colton and Poe, 1994). FNMOC alsopartners with NRL as lead agents for

Calibration/Validation of newly-flown passivemicrowave sensors. A less quantitative but operationally usefultechnique of using microwave imagery is that ofusing SSM/I 85 GHz imagery to locate tropicalcyclone centers and convective structure. This isused extensively at centers such as the JointTyphoon Warning Center in Pearl Harbor, Hawaiiwhich obtains the data from the Navy’s TropicalCyclone Web Page, currently in transition fromNRL Monterey to FNMOC (Hawkins et al., 2001).Figure 2 is an example of SSM/I 85 GHz imageryof TC Bilis and shows how clearly passivemicrowave can locate a circulation center via theconvective organization. The most valuableapplication of this is in cases when no clear eye isapparent in traditional VIS/IR imagery. Partnering with the NPOESS IntegratedProgram Office and the Space Test Program, NRLis developing the WindSat instrument (St. Germainand Gaiser, 2000). This effort is designed todemonstrate the ability of polarimetric methods to

retrieve wind direction as well as speed from apassive microwave instrument. FNMOC will bethe Payload Operations Center (POC) forWindSat. The Navy also makes use of other R&Dpassive sensors such as the TRMM TMI in muchthe same fashion as SSM/I. As in the case of IR sounders, microwavesounders play an important role in NWP. Againleveraging SPP partnerships, NESDIS SSM/T-1and T-2 soundings are used operationally in Navymodels. The integrated microwave imager andsounder, SSMIS, to be launched on the nextDMSP satellite, will be exploited similarly to SSM/Iand SSM/T-1/2, with some improvements likely tobe derived from the co-located conically scanningconfiguration.

4. SCATTEROMETRY

The scatterometer provides an importantsupplement to passive microwave methods forretrieval of ocean surface wind in providing winddirection and supplementing coverage. AtFNMOC, Navy model data is applied to thebackscatter from the QuikSCAT and ERS-2scatterometers to remove directional ambiguity ina product-line consistent fashion. Figure 3 is anexample of a web-based, interactive surface windspeed product that combines both scatterometryand passive microwave.

5. ALTIMETRY

The radar altimeter provides a function for theocean similar to that of a barometer for theatmosphere. The sea surface height, determinedby processing the altimeter range measurementwith a full set of corrections, is a function of thedensity of the water mass beneath it. Cold (dense)and warm (less dense) water masses arerepresented by differences in the sea surfaceheight of the column of water. Narrow geostrophiccurrents generated at the boundaries of watermasses are represented by rapid (10 to 100centimeters) changes in sea surfaces over arelatively short spatial scale (50 to 100 kilometers).These features are revealed in the sea surfaceheights generated by the radar altimeter (Figure 4).Mesoscale features are gleaned from acombination of altimeter sea surface height andsea surface temperature measurements. NRL Stennis Space Center devised a methodto assimilate sea surface height and sea surfacetemperature measurements to resolve a three-dimensional cube of the temperature, salinity, anddensity of the water column. The Modular OceanData Assimilation System (MODAS) wasdeveloped and transitioned to NAVO to assimilateGEOSAT Follow-On (GFO), Topex/Poseidon, andERS-2 altimeter data at the Altimeter Data FusionCenter. In a majority of ocean areas MODASprovides information that is superior to climatologyor climatology plus sea surface temperaturemeasurements alone. The Navy Layered OceanModel (NLOM) is a global/regional ocean modelcapable of assimilating sea surface heights.Model evaluations indicate that in order to properlyrepresent the mesoscale oceanic variability, analtimeter in a 17- or 35-day exact repeat orbit isadequate, although model improvements continuewith additional satellites up to a maximum of threealtimeters (Hurlburt, 2000). An altimeter ARP isbeing formed under the SPP to continueinvestigating improvements in altimeter researchand transitioning those efforts to operations.

6. SYNTHETIC APERATURE RADAR

Synthetic Aperture Radar (SAR) technologytakes advantage of the forward motion of thespacecraft carrying the active microwave radar tosynthetically increase the antenna size and acquiremore information from the signal, thus allowing ahigher spatial resolution to be extracted from thesignal. The U.S. National/Naval Ice Center (NIC)has the responsibility of mapping sea ice

FIG. 2 85 GHz (Horiz. Pol.) imagery from FNMOC.

conditions over all ocean regions of the world. Inaddition to visible and infrared imagery and iceimagery from the Special Sensor MicrowaveImager on the DMSP satellite, the Navy uses SARdata from the Canadian RADARSAT-1. Thesynthetic aperture radar (SAR) imagery isextensively used in the production of sea iceanalyses in U.S. waters and the Arctic. SAR dataallow an all-weather, day/night capability thatdetermines ice edge, ice coverage, and iceconcentration. Much of the analysis of the SAR data ismanual, but Navy and NOAA funded research isunderway to automate the processes to distinguishbetween first year and multiyear ice. Gineris et al.(2000) describe an operational evaluation ofARKTOS, a knowledge-based sea iceclassification system. ARKTOS is in use at NIC toaid in the mapping of ice covered oceans.

7. SPECTRAL APPLICATIONS

The utilization of multi-spectral data isincreasing in Naval METOC. Although the utilityof satellite-sensed ocean color data for Navaloperations has been known for some time, theavailability of real-time data has been the limitingfactor. The SeaWiFS sensor on Orbview-2 hasprovided the consistent data to implement oceancolor into operations. Recently transitioned fromR&D by NRL Stennis Space Center to NAVO,Figure 5 shows a chlorophyll product, which alongwith water clarity/visibility is now available forMETOC support of Naval expeditionary, special,and mine warfare operations. SeaWiFS is also showing promise inMeteorology in detecting sand/dust/aerosols. Inregions prone to major sand/dust events, theimpact on Naval operations is severe, andforecasting is challenging. Although the once perday frequency is insufficient, the clarity with whichmulti-spectral data depicts these events makes it auseful supplement to other analytical andforecasting tools. The cover of this volumedepicts a sand/dust event which is about toaccompany frontal passage on the Iberianpeninsula. The sand/dust was entrained into themid-latitude system beginning with easterly surfacewinds off of North Africa.

8. COMMERCIAL/HIGH-RES APPLICATIONS

The arrival of commercial high-resolutionimagery has brought new capability to efforts byNAVO’s Warfighting Support Center (WSC) to

support DoD customers in describing the oceanenvironment, particularly in the littorals. The latestgeneration of commercial satellites with aresolution of 1 m add to the existing usage ofsensors such as Landsat. Figure 6 is a product ofthe WSC which uses imagery as an “anchor” forproviding littoral oceanographic data pertinent toNavy and USMC operations.

9. SUMMARY

The Navy and Marine Corps extensively usesatellite data in operational METOC analysis andforecasting efforts, and are increasingly reliantupon satellites for gains in forecasting accuracyand quality of METOC support. We are engagedin strong partnerships, leveraging the expertiseareas of our SPP partners, acedemia and industry. Although the Navy maintains a focused R&Dcapability in critical areas of remote sensing,opportunities do exist for other researchers tocontribute and participate in areas which caneventually lead to operational usage.Collaboration by other government, academic andcommercial scientists with Navy labs such as NRLMonterey and with the Naval Postgraduate Schoolhave lead to many of the recent advancements inoperational remote sensing. NRL’s sponsor, theOffice of Naval Research, solicits proposals fromthe research community in specific areas ofinterest, information available from the ONRhomepage at http://www.onr.navy.mil. TheCRADA process provides a path for commercialdevelopers and vendors to partner with Navy.Finally, the Shared Processing Program maintainsAlgorithm Research Panels (ARP) in PassiveMicrowave, Altimetry, Satellite Soundings andMulti-Channel Sea Surface Temperature.Proposed algorithms or improvements in theseareas may be submitted to the appropriate ARPchair.

10. REFERENCES

Colton, M.C. and G.A. Poe, 1994: SharedProcessing Program, Defense MeteorologicalSatellite Program, Special Sensor Microwave/Imager Algorithm Symposium, June 8-10, 1993.Bull. Amer. Meteor. Soc. 75, 1663-1669.

Cornelius, C.J., J.L Haferman, and C.E.Skupniewicz, 2000: Operational Satellite DataProcessing at Fleet Numerical Meteorology andOceanography Center. Tenth Conference on

Satellite Meteorology and Oceanography, 9-14January, Long Beach, CA, 40-43.

Gineris, D., C. Bertoia, M.R. Keller, L.K. Soh andC. Tsatsoulis, 2000: Operational Evaluation of aKnowledge-Based Sea Ice Classification System,Proceedings of a Workshop on Mapping andArchiving of Sea Ice Data – The Expanded role ofRadar, Ottawa, Canada, May 2-4, 2000, WorldMeteorological Organization/TD No. 1027, 173-178.

Hawkins, J.D., T.F. Lee, J. Turk and K.Richardson, 2000: U.S. Navy Satellite MeterologyApplications – R&D to Applications. TenthConference on Satellite Meteorology andOceanography, 9-14 January, Long Beach, CA, 4-7.

____, ____, ____, C. Sampson, J. Dent, and K.Richardson, 2001: Real-Time Internet Distributionof Satellite Products for Tropical CycloneReconnaissance. Bull. Amer. Meteor. Soc. 82,567-578.

Hurlburt, H.E., R.C. Rhodes, C.N. Barron, E.J.Metzger, O.M. Smedstad, and J-F. Cayula, 2000:A Feasibility Demonstration of Ocean Model Eddy-Resolving Nowcast/Forecast Skill Using SatelliteAltimter Data. Naval Research LaboratoryMR/7320-00-8235, 23 pp. [Available from theNaval Research Laboratory Detachment, StennisSpace Center, MS 39522].

Rigney, J.P, R. Bouchard, C. Diamond, D.Bershire, D. L’Heureux, D. T. Conlee, M. C.Colton, and R.L. Crout, 1997: Oceanography fromSpace in Support of Naval Operations. MarineTech. Soc. Journal, 31, 31-40.

St. Germain, K.M. and P.W. Gaiser, 2000:Space Borne Polarimetric Microwave RadiometryAnd The Coriolis WindSat System, IEEEAerospace Conference Proceedings, 5,159-164.

Velden, S.C., C.M Hayden, S. J. Nieman, W.P.Menzel, S. Wanzong, and J.S. Goerss, 1997:Upper-Tropospheric Winds Derived fromGeostationary Satellite Water Vapor Observations.Bull. Amer. Meteor. Soc. 78, 173-194.

FIG. 3. Web-based, interactive surface windproduct from FNMOC, zoomed to reveal fullresolution data.

FIG. 4. MODAS Sea Surface Height (SSH)residuals product derived from altimetry.

FIG. 6. NAV

FIG. 5. SeaWiFS-derived Chlorophyll Concentration product fromNRL/NAVO. SeaWiFS data used with permission of ORBIMAGE.

O High Resolution Commercial Imagery Product: Special Analyzed Image Littoral (SAIL)