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Full-Text Articles in Physical Sciences and Mathematics

A New Interpretation Of Total Column Bro During Arctic Spring, R J. Salawitch, T Canty, T P. Kurosu, K Chance, Q Liang, Arlindo Da Silva, S Pawson, J E. Neilsen, J. V. Rodriguez, P K. Bhartia, X Liu, L Gregory Huey, J Liao, R E. Stickel, D Tanner, Jack E. Dibb, W R. Simpson, D Donohue, Andrew Weinheimer, F Flocke, D Knapp, D Montzka, J A. Neuman, J Nowak, Thomas B. Ryerson, S J. Oltmans, D R. Blake, E L. Atlas, D Kinnison, S Tilmes, L L. Pan, F Hendrick, R Bradley Pierce, M Van Roozendael, K Kreher, P V. Johnston, R S. Gao, B Johnson, T P. Bui, G Chen, R B. Pierce, J H. Crawford, D J. Jacob Nov 2010

A New Interpretation Of Total Column Bro During Arctic Spring, R J. Salawitch, T Canty, T P. Kurosu, K Chance, Q Liang, Arlindo Da Silva, S Pawson, J E. Neilsen, J. V. Rodriguez, P K. Bhartia, X Liu, L Gregory Huey, J Liao, R E. Stickel, D Tanner, Jack E. Dibb, W R. Simpson, D Donohue, Andrew Weinheimer, F Flocke, D Knapp, D Montzka, J A. Neuman, J Nowak, Thomas B. Ryerson, S J. Oltmans, D R. Blake, E L. Atlas, D Kinnison, S Tilmes, L L. Pan, F Hendrick, R Bradley Pierce, M Van Roozendael, K Kreher, P V. Johnston, R S. Gao, B Johnson, T P. Bui, G Chen, R B. Pierce, J H. Crawford, D J. Jacob

Earth Sciences

Emission of bromine from sea-salt aerosol, frost flowers, ice leads, and snow results in the nearly complete removal of surface ozone during Arctic spring. Regions of enhanced total column BrO observed by satellites have traditionally been associated with these emissions. However, airborne measurements of BrO and O3 within the convective boundary layer (CBL) during the ARCTAS and ARCPAC field campaigns at times bear little relation to enhanced column BrO. We show that the locations of numerous satellite BrO “hotspots” during Arctic spring are consistent with observations of total column ozone and tropopause height, suggesting a stratospheric origin to these …


Modelling Uncertainty Caused By Internal Waves On The Accuracy Of Mbes, Travis Hamilton, Jonathan Beaudoin Nov 2010

Modelling Uncertainty Caused By Internal Waves On The Accuracy Of Mbes, Travis Hamilton, Jonathan Beaudoin

Center for Coastal and Ocean Mapping

A 3D ray tracing model has been developed to estimate the effects of internal waves upon the accuracy of multibeam echosounders (MBES). A case study examines the variability in these effects as a function of survey line direction and also considers the case of improving 2D ray tracing models with wave parameters derived from MBES water column imagery. Results indicate that, under certain circumstances, the effects of internal waves can prove to be a significant source of uncertainty that detracts from the ability to efficiently map the seafloor with wide swath angles.


U.S. Law Of The Sea Cruises To Map Sections Of The Mariana Trench And The Eastern And Southern Insular Margins Of Guam And The Northern Mariana Islands, James V. Gardner Nov 2010

U.S. Law Of The Sea Cruises To Map Sections Of The Mariana Trench And The Eastern And Southern Insular Margins Of Guam And The Northern Mariana Islands, James V. Gardner

Center for Coastal and Ocean Mapping

U.S. Law of the Sea cruises to map sections of the Mariana Trench and the eastern and southern insular margins of Guam and the Northern Mariana Islands

CRUISE SU10-1

Leg 1: August 6 to September, 2010

Apra Harbor, Guam to Apra Harbor, Guam


Bromide And Other Ions In The Snow, Firn Air, And Atmospheric Boundary Layer At Summit During Gshox, Jack E. Dibb, Luke D. Ziemba, J Luxford, P Beckman Oct 2010

Bromide And Other Ions In The Snow, Firn Air, And Atmospheric Boundary Layer At Summit During Gshox, Jack E. Dibb, Luke D. Ziemba, J Luxford, P Beckman

Earth Sciences

Measurements of gas phase soluble bromide in the boundary layer and in firn air, and Br in aerosol and snow, were made at Summit, Greenland (72.5° N, 38.4° W, 3200 m a.s.l.) as part of a larger investigation into the influence of Br chemistry on HOx cycling. The soluble bromide measurements confirm that photochemical activation of Br in the snow causes release of active Br to the overlying air despite trace concentrations of Br in the snow (means 15 and 8 nmol Br kg−1 of snow in 2007 and 2008, respectively). Mixing ratios of …


R/V Thompson Em302 Sat -- Cruise Report, Jonathan Beaudoin, Val E. Schmidt Oct 2010

R/V Thompson Em302 Sat -- Cruise Report, Jonathan Beaudoin, Val E. Schmidt

Center for Coastal and Ocean Mapping

No abstract provided.


Correction Of Bathymetric Survey Artifacts Resulting From Apparent Wave-Induced Vertical Position Of An Auv, Val E. Schmidt, Nicole A. Raineault, Adam Skarke, Arthur Trembanis, Larry A. Mayer Oct 2010

Correction Of Bathymetric Survey Artifacts Resulting From Apparent Wave-Induced Vertical Position Of An Auv, Val E. Schmidt, Nicole A. Raineault, Adam Skarke, Arthur Trembanis, Larry A. Mayer

Center for Coastal and Ocean Mapping

Recent increases in the capability and reliability of autonomous underwater vehicles (AUVs) have provided the opportunity to conduct bathymetric seafloor surveys in shallow water (< 50 m). Unfortunately, surveys of this water depth may contain artifacts induced by large amplitude wave motion at the surface. The artifacts occur when an onboard pressure sensor determines the depth of the AUV. Waves overhead induce small pressure fluctuations at depth, which modulate the AUV’s pressure sensor output without causing actual vertical movement of the AUV. Since bathymetric measurements are made with respect to the AUV’s depth, these pressure fluctuations, in turn, modulate the measurement of the seafloor. The result is a periodic across-track, vertical offset of the seafloor profile (similar to a heave artifact sometimes common in surface vessel surveys). In this paper we describe our experience with the “Gavia” model AUV (Hafmynd EHF, Iceland) in a recent bathymetric survey during which wave action overhead induced such an artifact with a peak-to-peak amplitude as large as 1 meter. A method for removing the artifact as well as recommendations for modifications to the sonar, INS and AUV to mitigate the effect in the future are provided.


Acquisizione Magnetica Marina Dell'alto Strutturale Del Mt. Vercelli (Mar Tirreno Centrale) E Del Golfo Di Napoli: Descrizione Dei Rilievi E Primi Risultati, L. Cocchi, F. Muccini, C. Carmisciano, R. Vagni, Giuseppe Masetti Oct 2010

Acquisizione Magnetica Marina Dell'alto Strutturale Del Mt. Vercelli (Mar Tirreno Centrale) E Del Golfo Di Napoli: Descrizione Dei Rilievi E Primi Risultati, L. Cocchi, F. Muccini, C. Carmisciano, R. Vagni, Giuseppe Masetti

Center for Coastal and Ocean Mapping

Durante la Campagna Oceanografica Ver2010, effettuata nel mese di maggio 2010, sono stati acquisiti due set di dati geomagnetici marini in alta risoluzione relativi alle aree del Mt. Vercelli (Mar Tirreno Centrale) e del Golfo di Napoli. Tale attività di misura è stata resa possibile grazie alla collaborazione tecnica scientifica tra l’Unità di Progetto “Geofisica e Tecnologie Marine” dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV) e l’Istituto Idrografico della Marina (IIM). La proficua collaborazione è sancita dall’accordo di cooperazione “Co.Na.Ge.M” (Coordinamento Nazionale per la Geofisica Marina). Nello specifico, i due rilievi sono stati svolti mediante l’impiego della Nave Idro-oceanografica “Aretusa”, …


Real-Time Monitoring Of Uncertainty Due To Refraction In Multibeam Echo Sounding, Jonathan Beaudoin Oct 2010

Real-Time Monitoring Of Uncertainty Due To Refraction In Multibeam Echo Sounding, Jonathan Beaudoin

Center for Coastal and Ocean Mapping

A software toolkit has been developed to objectively monitor uncertainty due to refraction in multibeam echosounding, specifically mapping systems that employ underway sound speed profiling hardware. The toolkit relies on the use of a raytrace simulator which mimics the sounding geometry of any given echosounder, specifically array type, angular sector, draft, and availability of a surface sound speed probe. The simulator works by objectively comparing a pair of consecutively collected sound speed profiles and reporting sounding uncertainty across the entire potential sounding space. Realtime visualizations of the uncertainty as a function of time and space allow the operator to tune …


High Resolution Calibration Of A Multibeam Echo Sounder, Carlo Lanzoni, Thomas C. Weber Sep 2010

High Resolution Calibration Of A Multibeam Echo Sounder, Carlo Lanzoni, Thomas C. Weber

Center for Coastal and Ocean Mapping

Calibration can greatly increase the utility of collecting seafloor backscattering strength with multibeam echo sounders (MBES). A calibration procedure to determine high resolution, three dimensional transmit and receive beam patterns of a Reson SeaBat 7125 MBES was performed using the fresh water calibration tank at the University of New Hampshire. The measurements employed an omni-directional Reson TC4034 projector/hydrophone as a reference transducer at an acoustic distance of 13 m. The multibeam sonar system was configured for 256 beams equi-angle mode and operating frequency of 396 kHz. The transmit beam pattern was computed for across-track angular range between +/–90o in 0.1o …


The Production And Persistence Of Σrono2 In The Mexico City Plume, A E. Perring, T H. Bertram, D K. Farmer, Paul J. Wooldridge, Jack E. Dibb, N J. Blake, D R. Blake, H B. Singh, H Fuelberg, Glenn Diskin, G W. Sachse, Robert C. Cohen Aug 2010

The Production And Persistence Of Σrono2 In The Mexico City Plume, A E. Perring, T H. Bertram, D K. Farmer, Paul J. Wooldridge, Jack E. Dibb, N J. Blake, D R. Blake, H B. Singh, H Fuelberg, Glenn Diskin, G W. Sachse, Robert C. Cohen

Earth Sciences

Alkyl and multifunctional nitrates (RONO2, ΣANs) have been observed to be a significant fraction of NOy in a number of different chemical regimes. Their formation is an important free radical chain termination step ending production of ozone and possibly affecting formation of secondary organic aerosol. ΣANs also represent a potentially large, unmeasured contribution to OH reactivity and are a major pathway for the removal of nitrogen oxides from the atmosphere. Numerous studies have investigated the role of nitrate formation from biogenic compounds and in the remote atmosphere. Less attention has been paid to the role ΣANs may …


Synthesis Of Satellite (Modis), Aircraft (Icartt), And Surface (Improve, Epa-Aqs, Aeronet) Aerosol Observations Over Eastern North America To Improve Modis Aerosol Retrievals And Constrain Surface Aerosol Concentrations And Sources, Easan Drury, Daniel J. Jacob, Robert J.D. Spurr, Jun Wang, Yohei Shinozuka, Bruce E. Anderson, A D. Clarke, Jack E. Dibb, Cameron Mcnaughton, Rodney J. Weber Jul 2010

Synthesis Of Satellite (Modis), Aircraft (Icartt), And Surface (Improve, Epa-Aqs, Aeronet) Aerosol Observations Over Eastern North America To Improve Modis Aerosol Retrievals And Constrain Surface Aerosol Concentrations And Sources, Easan Drury, Daniel J. Jacob, Robert J.D. Spurr, Jun Wang, Yohei Shinozuka, Bruce E. Anderson, A D. Clarke, Jack E. Dibb, Cameron Mcnaughton, Rodney J. Weber

Earth Sciences

We use an ensemble of satellite (MODIS), aircraft, and ground-based aerosol observations during the ICARTT field campaign over eastern North America in summer 2004 to (1) examine the consistency between different aerosol measurements, (2) evaluate a new retrieval of aerosol optical depths (AODs) and inferred surface aerosol concentrations (PM2.5) from the MODIS satellite instrument, and (3) apply this collective information to improve our understanding of aerosol sources. The GEOS-Chem global chemical transport model (CTM) provides a transfer platform between the different data sets, allowing us to evaluate the consistency between different aerosol parameters observed at different times and …


Do Scientists Agree About Climate Change? Public Perceptions From A New Hampshire Survey, Lawrence C. Hamilton Jul 2010

Do Scientists Agree About Climate Change? Public Perceptions From A New Hampshire Survey, Lawrence C. Hamilton

The Carsey School of Public Policy at the Scholars' Repository

This report, a collaboration of the Carsey Institute, the UNH Survey Center, and the UNH Office of Sustainability, is the first of a new initiative that will track public perceptions about climate change as they change over time. Questions related to climate change were asked as part of New Hampshire's Granite State Poll, which surveyed 512 New Hampshire residents in April 2010.


Geodatabase Development To Support Hyperspectral Imagery Exploitation, Robert A. Fusina, John C. Fry, C Reid Nichols, Charles M. Bachmann, Rong-Rong Li, Jon Sellars, Christopher Parrish, Marcos J. Montes, Carl Gross, Stephen A. White, Krista Lee, Christopher A. Jones Jul 2010

Geodatabase Development To Support Hyperspectral Imagery Exploitation, Robert A. Fusina, John C. Fry, C Reid Nichols, Charles M. Bachmann, Rong-Rong Li, Jon Sellars, Christopher Parrish, Marcos J. Montes, Carl Gross, Stephen A. White, Krista Lee, Christopher A. Jones

Center for Coastal and Ocean Mapping

Geodatabase development for coastal studies conducted by the Naval Research Laboratory (NRL) is essential to support the exploitation of hyperspectral imagery (HSI). NRL has found that the remote sensing and mapping science community benefits from coastal classifications that group coastal types based on similar features. Selected features in project geodatabases relate to significant biological and physical forces that shape the coast. The project geodatabases help researchers understand factors that are necessary for imagery post processing, especially those features having a high degree of temporal and spatial variability. NRL project geodatabases include a hierarchy of environmental factors that extend from shallow …


Is New Hampshire's Climate Warming?, Lawrence C. Hamilton, Barry D. Keim, Cameron P. Wake Jul 2010

Is New Hampshire's Climate Warming?, Lawrence C. Hamilton, Barry D. Keim, Cameron P. Wake

The Carsey School of Public Policy at the Scholars' Repository

This Carsey brief looks at temperature anomalies across New Hampshire and shows that not only is the state warmer than it has been in the past, but it is also warming faster than much of the planet. Sociologist Lawrence Hamilton, research associate professor Cameron Wake, and former NH state climatologist Barry Keim analyzed over 100 years of temperatures across the state to produce this data for the Carsey Institute in August 2010.


U.S. Law Of The Sea Cruise To Map The Southern Flank Of The Kingman Reef-Palmyra Atoll Section Of The Line Islands, Equatorial Pacific Ocean, James V. Gardner, Brian R. Calder Jun 2010

U.S. Law Of The Sea Cruise To Map The Southern Flank Of The Kingman Reef-Palmyra Atoll Section Of The Line Islands, Equatorial Pacific Ocean, James V. Gardner, Brian R. Calder

Center for Coastal and Ocean Mapping

U.S. Law of the Sea Cruise to Map the Southern Flank of the Kingman Reef-Palmyra Atoll section of the Line Islands, Equatorial Pacific Ocean CRUISE KM1009 May 17, to June 16, 2010 Pago Pago, American Samoa to Honolulu, HI


The Arctic Research Of The Composition Of The Troposphere From Aircraft And Satellites (Arctas) Mission: Design, Execution, And First Results, D J. Jacob, J H. Crawford, H Maring, A D. Clarke, Jack E. Dibb, L K. Emmons, R A. Ferrare, C A. Hostetler, Phil Russell, H B. Singh, A M. Thompson, G E. Shaw, E Mccauley, Judith Pederson, Jenny Fisher Jun 2010

The Arctic Research Of The Composition Of The Troposphere From Aircraft And Satellites (Arctas) Mission: Design, Execution, And First Results, D J. Jacob, J H. Crawford, H Maring, A D. Clarke, Jack E. Dibb, L K. Emmons, R A. Ferrare, C A. Hostetler, Phil Russell, H B. Singh, A M. Thompson, G E. Shaw, E Mccauley, Judith Pederson, Jenny Fisher

Earth Sciences

The NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission was conducted in two 3-week deployments based in Alaska (April 2008) and western Canada (June–July 2008). Its goal was to better understand the factors driving current changes in Arctic atmospheric composition and climate, including (1) influx of mid-latitude pollution, (2) boreal forest fires, (3) aerosol radiative forcing, and (4) chemical processes. The June–July deployment was preceded by one week of flights over California (ARCTAS-CARB) focused on (1) improving state emission inventories for greenhouse gases and aerosols, (2) providing observations to test and improve models …


Hydrographic Products/Services As A Fundamental Component Of The E-Navigation Concept Of Operation, Lee Alexander, Robert Ward Jun 2010

Hydrographic Products/Services As A Fundamental Component Of The E-Navigation Concept Of Operation, Lee Alexander, Robert Ward

Center for Coastal and Ocean Mapping

e-Navigation is a recent initiative aimed at moving traditional maritime navigation towards a connected digital environment. Defined by the International Maritime Organization (IMO) as “the harmonized collection, integration, exchange, presentation and analysis of maritime information onboard and ashore by electronic means to enhance birth-to-birth navigation and related services, for safety and security at sea and protection of the marine environment”, e-Navigation is not a new system of equipment but more an operational concept. Three significant outcomes are envisioned: 1) Shipboard navigation systems will benefit from the integration of own ship sensors, supporting information, standard user interface, and a comprehensive system …


Application Of Jpeg 2000 Wavelet Compression To Multibeam Echosounder Mid-Water Acoustic Refectivity Measurements, Jonathan Beaudoin Jun 2010

Application Of Jpeg 2000 Wavelet Compression To Multibeam Echosounder Mid-Water Acoustic Refectivity Measurements, Jonathan Beaudoin

Center for Coastal and Ocean Mapping

No abstract provided.


New Approaches For Evaluating Lidar-Derived Shoreline, Christopher Parrish, Stephen A. White, Brian R. Calder, Shachak Pe'eri, Yuri Rzhanov Jun 2010

New Approaches For Evaluating Lidar-Derived Shoreline, Christopher Parrish, Stephen A. White, Brian R. Calder, Shachak Pe'eri, Yuri Rzhanov

Center for Coastal and Ocean Mapping

This study presents and compares two new methods of assessing the uncertainty of lidar-derived National Shoreline mapped by NOAA’s National Geodetic Survey: an empirical (ground-based) approach and a stochastic (Monte Carlo) approach. OCIS codes: (280.3640) Lidar; (120.2830) Height measurements; (000.4430) Numerical approximation and analysis


Simulating An Airborne Lidar Bathymetry (Alb) System, Shachak Pe'eri, Amaresh M. Kumar, Brian R. Calder Jun 2010

Simulating An Airborne Lidar Bathymetry (Alb) System, Shachak Pe'eri, Amaresh M. Kumar, Brian R. Calder

Center for Coastal and Ocean Mapping

This study’s focus is on the horizontal and vertical uncertainties associated with ALB measurements due to scattering through the water column. A lidar simulator was constructed and we present its design and preliminary results.


Seamless Online Distribution Of Amundsen Multibeam Data, James Muggah, Ian Church, Jonathan Beaudoin, John E. Hughes Clarke Jun 2010

Seamless Online Distribution Of Amundsen Multibeam Data, James Muggah, Ian Church, Jonathan Beaudoin, John E. Hughes Clarke

Center for Coastal and Ocean Mapping

Since 2003, all underway multibeam and sub-bottom data from the Canadian Coast Guard Ship Amundsen has been posted online within approximately six months of the end of each cruise. A custom interface allowing the user to access 15' latitude by 30' longitude mapsheets was implemented in 2006, allowing the user to download the bathymetric and backscatter data at 10 metre resolution. While this interface matched the underlying data management scheme implemented at the University of New Brunswick, the zoom and pan capability was at a fixed scale with limited contextual data. In the past few years, with the introduction of …


Modeling The Effect Of Oceanic Internal Waves On The Accuracy Of Multibeam Echosounders, Travis Hamilton, Jonathan Beaudoin Jun 2010

Modeling The Effect Of Oceanic Internal Waves On The Accuracy Of Multibeam Echosounders, Travis Hamilton, Jonathan Beaudoin

Center for Coastal and Ocean Mapping

When ray bending corrections are applied to multibeam echosounder (MBES) data, it is assumed that the varying layers of sound speed lie along horizontally stratified planes. In many areas internal waves occur at the interface where the water’s density changes abruptly (a pycnocline), this density gradient is often associated with a strong gradient in sound speed (a velocline). The internal wave introduces uncertainty into the echo soundings through two mechanisms: (1) tilting of the velocline, and (2) vertical oscillation of the velocline’s depth. A model has been constructed in order to examine how these effects degrade the accuracy of MBES …


4d Multimodal Visualization And Analysis Of Seafloor Vents And Plumes, Maurice Doucet, Mark Paton, James V. Gardner, Jens Greinert Jun 2010

4d Multimodal Visualization And Analysis Of Seafloor Vents And Plumes, Maurice Doucet, Mark Paton, James V. Gardner, Jens Greinert

Center for Coastal and Ocean Mapping

No abstract provided.


Convective Distribution Of Tropospheric Ozone And Tracers In The Central American Itcz Region: Evidence From Observations During Tc4, M A. Avery, Cynthia Twohy, David Mccabe, J Joiner, Kurt Severance, E L. Atlas, D R. Blake, T P. Bui, John D. Crounse, Jack E. Dibb, Glenn Diskin, Paul Lawson, Matthew Mcgill, David Rogers, G W. Sachse, Eric Scheuer, A M. Thompson, Charles Trepte, Paul Wennberg, Jerald Ziemke May 2010

Convective Distribution Of Tropospheric Ozone And Tracers In The Central American Itcz Region: Evidence From Observations During Tc4, M A. Avery, Cynthia Twohy, David Mccabe, J Joiner, Kurt Severance, E L. Atlas, D R. Blake, T P. Bui, John D. Crounse, Jack E. Dibb, Glenn Diskin, Paul Lawson, Matthew Mcgill, David Rogers, G W. Sachse, Eric Scheuer, A M. Thompson, Charles Trepte, Paul Wennberg, Jerald Ziemke

Earth Sciences

During the Tropical Composition, Clouds and Climate Coupling (TC4) experiment that occurred in July and August of 2007, extensive sampling of active convection in the ITCZ region near Central America was performed from multiple aircraft and satellite sensors. As part of a sampling strategy designed to study cloud processes, the NASA ER‐2, WB‐57 and DC‐8 flew in stacked “racetrack patterns” in convective cells. On July 24, 2007, the ER‐2 and DC‐8 probed an actively developing storm and the DC‐8 was hit by lightning. Case studies of this flight, and of convective outflow on August 5, 2007 reveal a significant anti‐correlation …


Evidence Of Nitric Acid Uptake In Warm Cirrus Anvil Clouds During The Nasa Tc4 Campaign, Eric Scheuer, Jack E. Dibb, Cynthia Twohy, David Rogers, Andrew J. Heymsfield, Aaron Bansemer May 2010

Evidence Of Nitric Acid Uptake In Warm Cirrus Anvil Clouds During The Nasa Tc4 Campaign, Eric Scheuer, Jack E. Dibb, Cynthia Twohy, David Rogers, Andrew J. Heymsfield, Aaron Bansemer

Earth Sciences

Uptake of HNO3 onto cirrus ice may play an important role in tropospheric NOx cycling. Discrepancies between modeled and in situ measurements of gas-phase HNO3 in the troposphere suggest that redistribution and removal mechanisms by cirrus ice have been poorly constrained. Limited in situ measurements have provided somewhat differing results and are not fully compatible with theory developed from laboratory studies. We present new airborne measurements of HNO3 in cirrus clouds from anvil outflow made during the Tropical Composition, Cloud, and Climate Coupling Experiment (TC4). Upper tropospheric (>9 km) measurements made during three flights while repeatedly traversing the same …


New Standards For Providing Meteorological And Hydrographic Information Via Ais Application-Specific Messages, Lee Alexander, Schwehr Kurt May 2010

New Standards For Providing Meteorological And Hydrographic Information Via Ais Application-Specific Messages, Lee Alexander, Schwehr Kurt

Center for Coastal and Ocean Mapping

AIS Application-specific messages transmitted in binary format will be increasingly used to digitally communicate maritime safety/security information between participating vessels and shore stations. This includes time-sensitive meteorological and hydrographic information that is critical for safe vessel transits and efficient ports/waterways management. IMO recently completed a new Safety-of-Navigation Circular (SN/Circ.) that includes a number of meteorologi-cal and hydrographic message applications and data parameters. In conjunction with the development of a new SN/Circ., IMO will establish an International Application (IA) Register for AIS Application-Specific Messages. IALA plans to establish a similar register for regional appli-cations. While there are no specific standards for …


Impact Of Mineral Dust On Nitrate, Sulfate, And Ozone In Transpacific Asian Pollution Plumes, T D. Fairlie, D J. Jacob, Jack E. Dibb, B Alexander, M A. Avery, Aaron Van Donkelaar, L Zhang Apr 2010

Impact Of Mineral Dust On Nitrate, Sulfate, And Ozone In Transpacific Asian Pollution Plumes, T D. Fairlie, D J. Jacob, Jack E. Dibb, B Alexander, M A. Avery, Aaron Van Donkelaar, L Zhang

Earth Sciences

We use a 3-D global chemical transport model (GEOS-Chem) to interpret aircraft observations of nitrate and sulfate partitioning in transpacific dust plumes during the INTEX-B campaign of April–May 2006. The model includes explicit transport of size-resolved mineral dust and its alkalinity, nitrate, and sulfate content. The observations show that particulate nitrate is primarily associated with dust, sulfate is primarily associated with ammonium, and Asian dust remains alkaline across the Pacific. This can be reproduced in the model by using a reactive uptake coefficient for HNO3 on dust (γ(HNO3) ~10−3) much lower than commonly assumed in …


Sea State Bias In Altimeter Sea Level Estimates Determined By Combining Wave Model And Satellite Data, N. Tran, Douglas C. Vandemark, S. Labroue, Hui Feng, Bertrand Chapron, H. L. Tolman, J. Lambin, N. Picot Mar 2010

Sea State Bias In Altimeter Sea Level Estimates Determined By Combining Wave Model And Satellite Data, N. Tran, Douglas C. Vandemark, S. Labroue, Hui Feng, Bertrand Chapron, H. L. Tolman, J. Lambin, N. Picot

Ocean Process Analysis Laboratory

This study documents a method for increasing the precision of satellite-derived sea level measurements. Results are achieved using an enhanced three-dimensional (3-D) sea state bias (SSB) correction model derived from both Jason-1 altimeter ocean observations (i.e., sea state and wind) and estimates of mean wave period from a numerical ocean wave model, NOAA’s WAVEWATCH III. A multiyear evaluation of Jason-1 data indicates sea surface height variance reduction of 1.26 (±0.2) cm2 in comparison to the commonly applied two-parameter SSB model. The improvement is similar for two separate variance reduction metrics and for separate annual data sets spanning 2002–2004. Spatial evaluation …


A Regional Scale Modeling Analysis Of Aerosol And Trace Gas Distributions Over The Eastern Pacific During The Intex-B Field Campaign, B Adhikary, Gregory R. Carmichael, S Kulkarni, C Wei, Y Tang, A D'Allura, M Mena-Carrasco, David G. Streets, Q Zhang, R B. Pierce, J Al-Saadi, L K. Emmons, G G. Pfister, M A. Avery, J D. Barrick, D R. Blake, William H. Brune, Robert C. Cohen, Jack E. Dibb, A Fried, B J. Heikes, L Gregory Huey, D W. O'Sullivan, G W. Sachse, R E. Shetter, H B. Singh, T L. Campos, C A. Cantrell, F Flocke, E J. Dunlea, Jose L. Jimenez, Andrew Weinheimer, John D. Crounse, Paul Wennberg, James J. Schauer, E A. Stone, D A. Jaffe, D R. Reidmiller Mar 2010

A Regional Scale Modeling Analysis Of Aerosol And Trace Gas Distributions Over The Eastern Pacific During The Intex-B Field Campaign, B Adhikary, Gregory R. Carmichael, S Kulkarni, C Wei, Y Tang, A D'Allura, M Mena-Carrasco, David G. Streets, Q Zhang, R B. Pierce, J Al-Saadi, L K. Emmons, G G. Pfister, M A. Avery, J D. Barrick, D R. Blake, William H. Brune, Robert C. Cohen, Jack E. Dibb, A Fried, B J. Heikes, L Gregory Huey, D W. O'Sullivan, G W. Sachse, R E. Shetter, H B. Singh, T L. Campos, C A. Cantrell, F Flocke, E J. Dunlea, Jose L. Jimenez, Andrew Weinheimer, John D. Crounse, Paul Wennberg, James J. Schauer, E A. Stone, D A. Jaffe, D R. Reidmiller

Earth Sciences

The Sulfur Transport and dEposition Model (STEM) is applied to the analysis of observations obtained during the Intercontinental Chemical Transport Experiment-Phase B (INTEX-B), conducted over the eastern Pacific Ocean during spring 2006. Predicted trace gas and aerosol distributions over the Pacific are presented and discussed in terms of transport and source region contributions. Trace species distributions show a strong west (high) to east (low) gradient, with the bulk of the pollutant transport over the central Pacific occurring between ∼20° N and 50° N in the 2-6 km altitude range. These distributions are evaluated in the eastern Pacific by comparison with …


Establishing A Regional Ais Application Specific Message Register, Lee Alexander, Kurt Schwehr, R Zetterberg Mar 2010

Establishing A Regional Ais Application Specific Message Register, Lee Alexander, Kurt Schwehr, R Zetterberg

Center for Coastal and Ocean Mapping

The goal of the Regional AIS Application Specific Message Register is to provide awareness of what applications exist, facilitate harmonization, and promote proper binary messaging for regional applications. To be hosted on the IALA website, establishing the Register will be a 3-step process: 1) Compile all existing AIS binaries into a Jcollection.K 2) Convert the JcollectionK into a Register. 3) Develop IALA guidance on best practices for creating and using AIS Binary Messages. Recommendations are provided in regard to: - Benefit of a web-based HTML user interface for input/output. - Use of XML to organize/format register applications in a consistent …