Physical Sciences and Mathematics Commons^™

A Modeling Experiment On The Grounding Of An Ice Shelf In The Central Arctic Ocean During Mis 6, Martin Jakobsson, M Siegert, Mark Paton

Center for Coastal and Ocean Mapping

High-resolution chirp sonar subbottom profiles from the Lomonosov Ridge in the central Arctic Ocean, acquired from the Swedish icebreaker Oden in 1996, revealed large-scale erosion of the ridge crest down to depths of 1000 m below present sea level [Jakobsson, 1999]. Subsequent acoustic mapping during the SCICEX nuclear submarine expedition in 1999 showed glacial fluting at the deepest eroded areas and subparallel ice scours from 950 m water depth to the shallowest parts of the ridge crest [Polyak et al., 2001]. The directions of the mapped glaciogenic bed-forms and the redeposition of eroded material on the Amerasian side of the …

Chemical And Physical Properties Of Bulk Aerosols Within Four Sectors Observed During Trace-P, C. Jordan, B E. Anderson, R. Talbot, Jack E. Dibb, H Fuelberg, Charlie Hudgins, C M. Kiley, R. S. Russo, Eric Scheuer, Garry Seid, K L. Thornhill, E L. Winstead

Earth Sciences

Chemical and physical aerosol data collected on the DC-8 during TRACE-P were grouped into four sectors based on back trajectories. The four sectors represent long-range transport from the west (WSW), regional circulation over the western Pacific and Southeast Asia (SE Asia), polluted transport from northern Asia with substantial sea salt at low altitudes (NNW) and a substantial amount of dust (Channel). WSW has generally low mixing ratios at both middle and high altitudes, with the bulk of the aerosol mass due to non-sea-salt water-soluble inorganic species. Low altitude SE Asia also has low mean mixing ratios in general, with the …

Uptake Of Nitrate And Sulfate On Dust Aerosols During Trace-P, C. Jordan, Jack E. Dibb, B E. Anderson, H Fuelberg

Earth Sciences

Aerosol data collected near Asia on the DC-8 aircraft platform during TRACE-P has been examined for evidence of uptake of NO₃⁻ and SO₄⁼ on dust surfaces. Data is compared between a sector where dust was predominant and a sector where dust was less of an influence. Coincident with dust were higher mixing ratios of anthropogenic pollutants. HNO₃, SO₂, and CO were higher in the dust sector than the nondust sector by factors of 2.7, 6.2, and 1.5, respectively. The colocation of dust and pollution sources allowed for the uptake of NO_{3 …}

Aerosol Chemical Composition In Asian Continental Outflow During The Trace-P Campaign: Comparison With Pem-West B, Jack E. Dibb, R. Talbot, Eric Scheuer, Garry Seid, Melody A. Avery, H B. Singh

Earth Sciences

Aerosol associated soluble ions and the radionuclide tracers ⁷Be and ²¹⁰Pb were quantified in 414 filter samples collected in spring 2001 from the DC-8 during the Transport and Chemical Evolution over the Pacific (TRACE-P) campaign. Binning the data into near Asia (flights from Hong Kong and Japan) and remote Pacific (all other flights) revealed large enhancements of NO₃⁻, SO₄⁼, C₂O₄⁼, NH₄⁺, K⁺, Mg²⁺, and Ca²⁺ near Asia. The boundary layer and lower troposphere were most strongly influenced by continental …

Intercontinental Transport Of Pollution Manifested In The Variability And Seasonal Trend Of Springtime O3 At Northern Middle And High Latitudes, Yuhang Wang, Changsub Shim, Nicola J. Blake, D R. Blake, Yunsoo Choi, Brian Ridley, Jack E. Dibb, Anthony Wimmers, Jennie Moody, F Flocke, Andrew Weinheimer, R. Talbot, Elliot Atlas

Earth Sciences

Observations (0–8 km) from the Tropospheric Ozone Production about the Spring Equinox (TOPSE) experiment are analyzed to examine air masses contributing to the observed variability of springtime O₃ and its seasonal increase at 40°–85°N over North America. Factor analysis using the positive matrix factorization and principal component analysis methods is applied to the data set with 14 chemical tracers (O₃, NO_y, PAN, CO, CH₄, C₂H₂, C₃H₈, CH₃Cl, CH₃Br, C₂Cl₄, CFC-11, HCFC-141B, Halon-1211, and ⁷Be) and one …

Remote Sensing Of Sediment Characteristics By Optimized Echo-Envelope Matching, Daniel D. Sternlicht, Christian De Moustier

Center for Coastal and Ocean Mapping

A sediment geoacoustic parameter estimation technique is described which compares bottom returns, measured by a calibrated monostatic sonar oriented within 15° of vertical and having a 10°–21° beamwidth, with an echo envelope model based on high-frequency (10–100 kHz) incoherent backscattertheory and sediment properties such as: mean grain size, strength, and exponent of the power law characterizing the interface roughness energy density spectrum, and volume scattering coefficient. An average echo envelope matching procedure iterates on the reflection coefficient to match the peak echo amplitude and separate coarse from fine-grain sediments, followed by a global optimization using a combination of simulated annealing …

Hypsometry, Volume And Physiography Of The Arctic Ocean And Their Paleoceanographic Implications, Martin Jakobsson, Ron Macnab, Arthur Grantz, Yngue Kristoffersen

Center for Coastal and Ocean Mapping

Recent analyses of the International Bathymetric Chart of the Arctic Ocean (IBCAO) grid model include: Hypsometry (the distribution of surface area at various depths); ocean volume distribution; and physiographic provinces [Jakobsson 2002; Jakobsson et al., in press]. The present paper summarizes the main results from these recent studies and expands on the paleoceanographic implications for the Arctic Ocean, which in this work is defined as the broad continental shelves of the Barents, Kara, Laptev, East Siberian and Chukchi Seas, the White Sea and the narrow continental shelves of the Beaufort Sea, the Arctic continental margins off the Canadian Arctic Archipelago …

Time Dependent Seafloor Acoustic Backscatter (10-100khz), Daniel D. Sternlicht, Christian De Moustier

Center for Coastal and Ocean Mapping

A time-dependent model of the acoustic intensity backscattered by the seafloor is described and compared with data from a calibrated, vertically oriented, echo-sounder operating at 33 and 93 kHz. The model incorporates the characteristics of the echo-sounder and transmitted pulse, and the water column spreading and absorption losses. Scattering from the water–sediment interface is predicted using Helmholtz–Kirchhoff theory, parametrized by the mean grain size, the coherent reflection coefficient, and the strength and exponent of a power-law roughness spectrum. The composite roughness approach of Jackson et al. [J. Acoust. Soc. Am. 79, 1410–1422 (1986)], modified for the finite duration of …

Chemical Composition Of Asian Continental Outflow Over The Western Pacific: Results From Transport And Chemical Evolution Over The Pacific (Trace-P), R. S. Russo, R. Talbot, Jack E. Dibb, Eric Scheuer, Garry Seid, C. Jordan, H Fuelberg, G W. Sachse, M A. Avery, S Vay, D R. Blake, N J. Blake, E L. Atlas, A Fried, S T. Sandholm, D Tan, H B. Singh, J Snow, B J. Heikes

Earth Sciences

We characterize the chemical composition of Asian continental outflow observed during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) mission during February–April 2001 in the western Pacific using data collected on the NASA DC-8 aircraft. A significant anthropogenic impact was present in the free troposphere and as far east as 150°E longitude reflecting rapid uplift and transport of continental emissions. Five-day backward trajectories were utilized to identify five principal Asian source regions of outflow: central, coastal, north-northwest (NNW), southeast (SE), and west-southwest (WSW). The maximum mixing ratios for several species, such as CO, C₂Cl₄, …

Large-Scale Ozone And Aerosol Distributions, Air Mass Characteristics, And Ozone Fluxes Over The Western Pacific Ocean In Late Winter/Early Spring, Edward V. Browell, Marta Fenn, Carolyn Butler, William B. Grant, Vincent G. Brackett, Jonathan Hair, Melody A. Avery, Yuanlong Hu, Reginald E. Newell, H Fuelberg, Daniel J. Jacob, Bruce E. Anderson, Elliot Atlas, D R. Blake, William H. Brune, Jack E. Dibb, A Fried, B J. Heikes, G W. Sachse, S T. Sandholm, Hanwant B. Singh, R. Talbot, S Vay, Rodney J. Weber, Karen B. Bartlett

Earth Sciences

Large-scale measurements of ozone (O₃) and aerosol distributions were made from the NASA DC-8 aircraft during the Transport and Chemical Evolution over the Pacific (TRACE-P) field experiment conducted in February–April 2001. Remote measurements were made with an airborne lidar to provide O₃ and multiple-wavelength aerosol backscatter profiles from near the surface to above the tropopause along the flight track. In situ measurements of O₃, aerosols, and a wide range of trace gases were made onboard the DC-8. Five-day backward trajectories were used in conjunction with the O₃ and aerosol distributions on each flight to …

Reactive Nitrogen In Asian Continental Outflow Over The Western Pacific: Results From The Nasa Transport And Chemical Evolution Over The Pacific (Trace-P) Airborne Mission, R. Talbot, Jack E. Dibb, Eric Scheuer, Garry Seid, R. S. Russo, S T. Sandholm, D Tan, H B. Singh, D R. Blake, N J. Blake, Elliot Atlas, G W. Sachse, C. Jordan, Melody A. Avery

Earth Sciences

We present here results for reactive nitrogen species measured aboard the NASA DC-8 aircraft during the Transport and Chemical Evolution over the Pacific (TRACE-P) mission. The large-scale distributions total reactive nitrogen (NO_y,sum = NO + NO₂ + HNO₃ + PAN + C₁–C₅alkyl nitrates) and O₃ and CO were better defined in the boundary layer with significant degradation of the relationships as altitude increased. Typically, NO_y,sum was enhanced over background levels of ∼260 pptv by 20-to-30-fold. The ratio C₂H₂/CO had values of 1–4 at altitudes up to 10 …

Summary Of Measurement Intercomparisons During Trace-P, Fred Eisele, Lee Mauldin, C A. Cantrell, M Zondlo, E C. Apel, A Fried, J Walega, R E. Shetter, Barry Lefer, F Flocke, Andrew Weinheimer, M A. Avery, S Vay, G W. Sachse, J Podolske, G S. Diskin, J D. Barrick, H B. Singh, William H. Brune, H Harder, M Martinez, A R. Bandy, D C. Thornton, B J. Heikes, Y Kondo, D Riemer, S T. Sandholm, R. Talbot, Jack E. Dibb

Earth Sciences

The NASA DC-8 and P-3B aircraft flew within about a kilometer or less of each other on three occasions during the Transport and Chemical Evolution Over the Pacific (TRACE-P) campaign in order to intercompare similar measurements on the two aircraft. The first and last intercomparisons were in relatively remote marine environments during transits to and from Asia. The first began with a boundary layer measurement followed by an ascent to 3 km. The second set of intercomparisons was at a fixed altitude of about 5.2 km off the coast of Japan, also in relatively clean air. Finally, the third measurement …

High-Frequency Volume And Boundary Acoustic Backscatter Fluctuations In Shallow Water, Timothy C. Gallaudet, Christian De Moustier

Center for Coastal and Ocean Mapping

Volume and boundary acoustic backscatter envelope fluctuations are characterized from data collected by the Toroidal Volume Search Sonar (TVSS), a 68 kHz cylindrical array capable of 360° multibeam imaging in the vertical plane perpendicular to its axis. The data are processed to form acoustic backscatter images of the seafloor, sea surface, and horizontal and vertical planes in the volume, which are used to attribute nonhomogeneous spatial distributions of zooplankton, fish, bubbles and bubble clouds, and multiple boundary interactions to the observed backscatter amplitude statistics. Three component Rayleigh mixture probability distribution functions (PDFs) provided the best fit to the empirical distribution …

Haptic-Geozui3d: Exploring The Use Of Haptics In Auv Path Planning, Rick Komerska, Colin Ware

Center for Coastal and Ocean Mapping

We have developed a desktop virtual reality system that we call Haptic-GeoZui3D, which brings together 3D user interaction and visualization to provide a compelling environment for AUV path planning. A key component in our system is the PHANTOM haptic device (SensAble Technologies, Inc.), which affords a sense of touch and force feedback – haptics – to provide cues and constraints to guide the user’s interaction. This paper describes our system, and how we use haptics to significantly augment our ability to lay out a vehicle path. We show how our system works well for quickly defining simple waypoint-towaypoint (e.g. transit) …

Haptic-Geozui3d: Exploring The Use Of Haptics In Auv Path Planning, Rick Komerska, Colin Ware, Matthew D. Plumlee, Roland J. Arsenault

Center for Coastal and Ocean Mapping

No abstract provided.

Report On The Lots Cruise To Map Foot Of The Slope And 2500-M Isobath Of Bowers Ridge And Beringian Margin, Bering Sea. Cruise Report, James V. Gardner

Center for Coastal and Ocean Mapping

Report on the LOTS cruise to map foot of the slope and 2500-m isobath of Bowers Ridge and Beringian margin, Bering Sea

July 7, to July 28, 2003

Dutch Harbor, AK to Dutch Harbor, AK

Integrating Multiple 3d Views Through Frame-Of-Reference Interaction, Matthew D. Plumlee, Colin Ware

Center for Coastal and Ocean Mapping

Frame-of-reference interaction consists of a unified set of 3D interaction techniques for exploratory navigation of large virtual spaces in nonimmersive environments. It is based on a conceptual framework that considers navigation from a cognitive perspective, as a way of facilitating changes in user attention from one reference frame to another, rather than from the mechanical perspective of moving a camera between different points of interest. All of our techniques link multiple frames of reference in some meaningful way. Some techniques link multiple windows within a zooming environment while others allow seamless changes of user focus between static objects, moving objects, …

Automatic Processing Of High-Rate, High-Density Multibeam Echosounder Data, Brian R. Calder, Larry A. Mayer

Center for Coastal and Ocean Mapping

Multibeam echosounders (MBES) are currently the best way to determine the bathymetry of large regions of the seabed with high accuracy. They are becoming the standard instrument for hydrographic surveying and are also used in geological studies, mineral exploration and scientific investigation of the earth's crustal deformations and life cycle. The significantly increased data density provided by an MBES has significant advantages in accurately delineating the morphology of the seabed, but comes with the attendant disadvantage of having to handle and process a much greater volume of data. Current data processing approaches typically involve (computer aided) human inspection of all …

Be-10/Be-7 Tracer Of Atmospheric Transport And Stratosphere-Troposphere Exchange, C. Jordan, Jack E. Dibb, R C. Finkel

Earth Sciences

The ¹⁰Be/⁷Be ratio is a sensitive tracer of atmospheric transport and stratosphere-troposphere exchange (STE). Data from five NASA aircraft field missions (PEM: West A and B, Tropics A; SONEX; and SUCCESS) have been assembled to produce the largest data set of ¹⁰Be,⁷Be, and their ratio collected to date (>300 samples). Ratios near 0.60 are indicative of tropospheric air with little stratospheric influence, while higher ratios are found in stratospheric air. Samples from the lower stratosphere were all collected within 2.5 km of the tropopause and had ratios >1.27. Of these lower stratosphere samples …

Analysis Of Data Relevant To Establishing Outer Limits Of A Continental Shelf Under Law Of The Sea Article 76, Martin Jakobsson, Larry A. Mayer, Andy Armstrong

Center for Coastal and Ocean Mapping

Coastal states may extend the limits of their juridically defined continental shelf beyond 200 nautical miles from their baselines under the provisions set forth in Article 76 of the United Nations Convention on the Law of the Sea (UNCLOS). In a preparatory desktop study, the University of New Hampshire’s Center for Coastal and Ocean Mapping/Joint Hydrographic Center analysed existing U.S. bathymetric and geophysical data holdings, identified data adequacy, and survey requirements to prepare a U.S. claim beyond the Exclusive Economical Zone (EEZ). In this paper we describe the methodology for our desktop study with particular emphasis on how we assembled …

Paleomagnetic Chronology Of Arctic Ocean Sediment Cores: Reversals And Excursions -The Conundrum, Reidar Lovlie, Martin Jakobsson, Jan Backman

Center for Coastal and Ocean Mapping

Chronologies of Arctic Ocean sediment cores are mainly based on interpretation of paleomagnetic inclination records. The first paleomagnetic chronology assigned zones with negative inclinations to polarity reversals (Steuerwald et al, 1968) because geomagnetic excursions at that time were a novel observation and had only been reported from lavas. Arctic Ocean sedimentation rates were thus established to be in the mm/ka-range. A general recognition of excursions as real features of the geomagnetic field emerged more than three decades later, and presently there is still no consensus regarding the number (or name), duration and age of global synchronous excursions within the Brunhes …

The International Bathymetric Chart Of The Arctic Ocean (Ibcao): An Improved Morphological Framework For Oceanographic Investigations, Ron Macnab, Martin Jakobsson

Center for Coastal and Ocean Mapping

The IBCAO initiative set out in late 1997 to assemble and merge all available bathymetric observations from northern regions, with the intent of constructing a reliable and up-to-date portrayal of the Arctic seabed in digital and printed form. In early 2000, a provisional grid and map were placed in circulation for public review and comment. Available for free downloading from a website hosted by the U.S. National Geophysical Data Center, these products won immediate acceptance from a broad spectrum of Arctic investigators who recognized the potential worth of the new information in a variety of applications ranging from straightforward map …

Fusing Information In A 3d Chart-Of-The-Future Display, Roland J. Arsenault, Matthew D. Plumlee, Shep M. Smith Lt, Colin Ware, Rick Brennan, Larry A. Mayer

Center for Coastal and Ocean Mapping

No abstract provided.

Fusing Information In A 3d Chart-Of-The-Future Display, Roland J. Arsenault, Shep M. Smith Lt, Colin Ware, Larry A. Mayer, Matthew D. Plumlee

Center for Coastal and Ocean Mapping

The Data Visualization Research Lab at the Center for Coastal and Ocean Mapping is investigating how three-dimensional navigational displays can most effectively be constructed. This effort is progressing along multiple paths and is implemented in the GeoNav3D system, a 3D chart-of-the-future research prototype. We present two lines of investigation here. First, we explore how tide, depth, and planning information can be combined (fused) into a single view, in order to give the user a more realistic picture of effective water depths. In the GeoNav3D system, 3D shaded bathymetry, coded for color depth, is used to display navigable areas. As in …

Electronic Chart Of The Future: The Hampton Roads Project, Rick Brennan, Colin Ware, Lee Alexander, Andy Armstrong, Larry A. Mayer, Lloyd C. Huff, Brian R. Calder, Shep M. Smith Lt, Matthew D. Plumlee, Roland J. Arsenault, Gerd Glang

Center for Coastal and Ocean Mapping

ECDIS is evolving from a two-dimensional static display of chart-related data to a decision support system capable of providing real-time or forecast information. While there may not be consensus on how this will occur, it is clear that to do this, ENC data and the shipboard display environment must incorporate both depth and time in an intuitively understandable way. Currently, we have the ability to conduct high-density hydrographic surveys capable of producing ENCs with decimeter contour intervals or depth areas. Yet, our existing systems and specifications do not provide for a full utilization of this capability. Ideally, a mariner should …

Marine Information Objects (Mio) And Ecdis: Concept And Practice, Lee Alexander

Center for Coastal and Ocean Mapping

Marine Information Objects (MIOs) consist of chart- and navigation-related information that supplement the minimum information required by ECDIS to ensure safety of navigation at sea. As related to the use of Electronic Navigational Chart (ENC) data, MIOs are additional, non-mandatory information not already covered by existing IMO, IHO, or IEC standards. Such information includes ice coverage, tide/water level, current flow, meteorological, oceanographic, and marine habitats. A Harmonization Group on MIOs (HGMIO) has been established between IHO and IEC to recommend additional data and display specifications that may be incorporated into future editions of IHO and IEC standards. This paper discusses …

Providing The Third Dimension: High-Resolution Multibeam Sonar As A Tool For Archaeological Investigations - An Example From The D-Day Beaches Of Normandy, Larry A. Mayer, Brian R. Calder, J S. Schmidt, C Malzone

Center for Coastal and Ocean Mapping

In general, marine archaeological investigations begin in the archives, using historic maps, coast surveys, and other materials, to define submerged areas suspected to contain potentially significant historical sites. Following this research phase, a typical archaeological survey uses sidescan sonar and marine magnetometers as initial search tools. Targets are then examined through direct observation by divers, video, or photographs. Magnetometers can demonstrate the presence, absence, and relative susceptibility of ferrous objects but provide little indication of the nature of the target. Sidescan sonar can present a clear image of the overall nature of a target and its surrounding environment, but the …

Stratospheric Influence On The Northern North American Free Troposphere During Topse: 7be As A Stratospheric Tracer, Jack E. Dibb, R. Talbot, Eric Scheuer, Garry Seid, Linsey J. Debell, Barry Lefer, Brian Ridley

Earth Sciences

We use ⁷Be, with HNO₃ and O₃, to identify air masses sampled from the NCAR C-130 during TOPSE that retained clear evidence of stratospheric influence. A total of 43 such air masses, spread fairly evenly across the February to May sampling period, and 40°N–86°N latitude range, were encountered. South of 55°N, nearly all clear stratospheric influence was restricted to altitudes above 6 km. At higher latitudes stratospherically influenced air masses were encountered as low as 2 km. Approximately 12% of all TOPSE sampling time at altitudes above 2 km was spent in stratospherically impacted air, above …

Effect Of Sulfate Aerosol On Tropospheric Nox And Ozone Budgets: Model Simulations And Topse Evidence, Xuexi Tie, L K. Emmons, Larry Horowitz, Guy Brasseur, Brian Ridley, Elliot Atlas, Craig Stround, Peter Hess, Andrzej Klonecki, Sasha Madronich, R. Talbot, Jack E. Dibb

Earth Sciences

The distributions of NO_x and O₃ are analyzed during TOPSE (Tropospheric Ozone Production about the Spring Equinox). In this study these data are compared with the calculations of a global chemical/transport model (Model for OZone And Related chemical Tracers (MOZART)). Specifically, the effect that hydrolysis of N₂O₅ on sulfate aerosols has on tropospheric NO_x and O₃ budgets is studied. The results show that without this heterogeneous reaction, the model significantly overestimates NO_x concentrations at high latitudes of the Northern Hemisphere (NH) in winter and spring in comparison to the observations during TOPSE; …

Tunable Diode Laser Measurements Of Formaldehyde During The Topse 2000 Study: Distributions, Trends, And Model Comparisons, A Fried, Yuhang Wang, C A. Cantrell, B Wert, J Walega, Brian Ridley, Elliot Atlas, R E. Shetter, Barry Lefer, Michael T. Coffey, James W. Hannigan, D R. Blake, N J. Blake, Simone Meinardi, R. Talbot, Jack E. Dibb, Eric Scheuer, Oliver Wingenter, J Snow, B J. Heikes, Dieter Ehhalt

Earth Sciences

Airborne measurements of formaldehyde (CH₂O) were acquired employing tunable diode laser absorption spectroscopy (TDLAS) during the 2000 Tropospheric Ozone Production About the Spring Equinox (TOPSE) study. This study consisted of seven deployments spanning the time period from 4 February to 23 May 2000 and covered a wide latitudinal band from 40°N to 85°N. The median measured CH₂O concentrations, with a few exceptions, did not show any clear temporal trends from February to May in each of five altitude and three latitude bins examined. Detailed measurement–model comparisons were carried out using a variety of approaches employing two …