Physical Sciences and Mathematics Commons^™

Formation Of Even-Numbered Hydrogen Cluster Cations In Ultracold Helium Droplets, S. Jaksch, A. Mauracher, A. Bacher, S. Denifl, F. Ferreira De Silva, H. Schoebel, Olof E. Echt, T. D. Maerk, M. Probst, D. K. Bohme, P. Scheier

Physics & Astronomy

Neutral hydrogen clusters are grown in ultracold helium nanodroplets by successive pickup of hydrogen molecules. Even-numbered hydrogen cluster cations are observed upon electron-impact ionization with and without attached helium atoms and in addition to the familiar odd-numbered H(n)(+). The helium matrix affects the fragmentation dynamics that usually lead to the formation of overwhelmingly odd-numbered H(n)(+). The use of high-resolution mass spectrometry allows the unambiguous identification of even-numbered H(n)(+) up to n congruent to 120 by their mass excess that distinguishes them from He(n)(+), mixed He(m)H(n)(+), and background ions. The large range in size of these hydrogen cluster ions is unprecedented, …

Global Irrigation Water Demand: Variability And Uncertainties Arising From Agricultural And Climate Data Sets, Dominik Wisser, Steve Frolking, Ellen M. Douglas, Balazs M. Fekete, Charles Vorosmarty, Andreas H. Schumann

Earth Sciences

Agricultural water use accounts for around 70% of the total water that is withdrawn from surface water and groundwater. We use a new, gridded, global-scale water balance model to estimate interannual variability in global irrigation water demand arising from climate data sets and uncertainties arising from agricultural and climate data sets. We used contemporary maps of irrigation and crop distribution, and so do not account for variability or trends in irrigation area or cropping. We used two different global maps of irrigation and two different reconstructions of daily weather 1963–2002. Simulated global irrigation water demand varied by ∼30%, depending on …

Integrating Landscapes That Have Experienced Rural Depopulation And Ecological Homogenization Into Tropical Conservation Planning, Aerin L. Jacob, Ismael Vaccaro, Raja Sengupta, Joel N. Hartter, Colin A. Chapman

Geography

If current trends of declining fertility rates and increasing abandonment of rural land as a result of urbanization continue, this will signal a globally significant transformation with important consequences for policy makers interested in conservation planning. This transformation is presently evident in a number of countries and projections suggest it may occur in the future in many developing countries. We use rates of population growth and urbanization to project population trends in rural areas for 25 example countries. Our projections indicate a general decline in population density that has either occurred already (e.g., Mexico) or may occur in the future …

Observations Of Clustering Inside Oceanic Bubble Clouds And The Effect On Short-Range Acoustic Propagation, Thomas C. Weber

Center for Coastal and Ocean Mapping

It has recently been shown [Weber, T. C. et al. (Year: 2007). “Acoustic propagation through clustered bubble clouds,” IEEE J. Ocean. Eng.32, 513–523] that gas bubble clustering plays a role in determining the acoustic field characteristics of bubbly fluids. In particular, it has been shown that clustering changes the bubble-induced attenuation as well as the ping-to-ping variability in the acoustic field. The degree to which bubble clustering exists in nature, however, is unknown. This paper describes a method for quantifying bubble clustering using a high frequency (400kHz) multibeam sonar, and reports on observations of near-surface bubbleclustering during a storm ( …

Transpacific Transport Of Ozone Pollution And The Effect Of Recent Asian Emission Increases On Air Quality In North America: An Integrated Analysis Using Satellite, Aircraft, Ozonesonde, And Surface Observations, D Zhang, D J. Jacob, K F. Boersma, D A. Jaffe, J R. Olson, K W. Bowman, J Worden, A M. Thompson, M A. Avery, Ronald C. Cohen, Jack E. Dibb, F Flocke, H Fuelberg, L Gregory Huey, W W. Mcmillan, H B. Singh, Andrew Weinheimer

Earth Sciences

We use an ensemble of aircraft, satellite, sonde, and surface observations for April-May 2006 (NASA/INTEX-B aircraft campaign) to better understand the mechanisms for transpacific ozone pollution and its implications for North American air quality. The observations are interpreted with a global 3-D chemical transport model (GEOS-Chem). OMI NO2 satellite observations constrain Asian anthropogenic NOx emissions and indicate a factor of 2 increase from 2000 to 2006 in China. Satellite observations of CO from AIRS and TES indicate two major events of Asian transpacific pollution during INTEX-B. Correlation between TES CO and ozone observations shows evidence for transpacific ozone pollution. The …

Geocoastpilot: Linking The Coast Pilot With Geo-Referenced Imagery & Chart Information, Kurt Schwehr, Matthew D. Plumlee, Briana M. Sullivan, Colin Ware

Center for Coastal and Ocean Mapping

No abstract provided.

Uncertainty Representation In Hydrographic Surveys And Products, Brian R. Calder

Center for Coastal and Ocean Mapping

No abstract provided.

Using Moored Arrays And Hyperspectral Aerial Imagery To Develop Nutrient Criteria For New Hampshire's Estuaries, J. Ru Morrison, Thomas K. Gregory, Shachak Pe'eri, William H. Mcdowell, Philip Trowbridge

PREP Reports & Publications

Increasing nitrogen concentrations and declining eelgrass beds in Great Bay, NH are clear indicators of impending problems for the state’s estuaries. A workgroup established in 2005 by the NH Department of Environmental Services and the NH Estuaries Project (NHEP) adopted eelgrass survival as the water quality target for nutrient criteria development for NH’s estuaries. In 2007, the NHEP received a grant from the U.S. Environmental Protection Agency to collect water quality information including that from moored sensors and hyper-spectral imagery data of the Great Bay Estuary. Data from the Great Bay Coastal Buoy, part of the regional Integrated Ocean Observing …

U.S. Law Of The Sea Cruise To Map The Foot Of The Slope And 2500-M Isobath Of The U.S. Arctic Ocean Margin. Cruise Report For 2008, Larry A. Mayer, Andy Armstrong

Center for Coastal and Ocean Mapping

USCGC Icebreaker Healy (WAGB-20)

U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin

CRUISES HE-0805

August 14 to September 5, 2008

Barrow, AK to Barrow, AK

Enhanced Secondary Organic Aerosol Formation Due To Water Uptake By Fine Particles, Stephen R. Hennigan, M Bergin, Jack E. Dibb, Rodney J. Weber

Earth Sciences

This study characterizes the partitioning behavior of a significant fraction of the ambient organic aerosol through simultaneous measurements of gas and particle watersoluble organic carbon (WSOC). During the summer in Atlanta, WSOC gas/particle partitioning showed a strong RH dependence that was attributed to particulate liquid water. At elevated RH levels (>70%) a significant increase in WSOC partitioning to the particle phase was observed and followed the predicted water uptake by fine particles. The enhancement in particle-phase partitioning translated to increased median particle WSOC concentrations ranging from 0.3 –0.9 mgCm3 . The results provide a detailed overview of the WSOC …

Posteruptive Phenomena In Coronal Mass Ejections And Substorms: Indicators Of A Universal Process?, K. K. Reeves, T. B. Guild, W. J. Hughes, K. E. Korreck, J. Lin, J. Raymond, S. Savage, Nathan A. Schwadron, Harlan E. Spence, D. F. Webb, M. Wiltberger

Physics & Astronomy

[1] We examine phenomena associated with eruptions in the two different regimes of the solar corona and the terrestrial magnetosphere. We find striking similarities between the speeds of shrinking magnetic field lines in the corona and dipolarization fronts traversing the magnetosphere. We also examine the similarities between supra-arcade downflows observed during solar flares and bursty bulk flows seen in the magnetotail and find that these phenomena have remarkably similar speeds, velocity profiles, and size scales. Thus we show manifest similarities in the magnetic reconfiguration in response to the ejection of coronal mass ejections in the corona and the ejection of …

High-Efficiency Resonant Rf Spin Rotator With Broad Phase Space Acceptance For Pulsed Polarized Cold Neutron Beams, P. N. Seo, L. Barron-Palos, J. D. Bowman, T. E. Chupp, C Crawford, M. Dabaghyan, M. Dawkins, S. J. Freedman, T. Gentile, M. T. Gericke, R. C. Gillis, G. L. Greene, F. William Hersman, G. L. Jones, M. Kandes, S. Lamoreaux, B. Lauss, M. B. Lueschner, R. Mahurin, M. Mason, J. Mei, G. S. Mitchell, H. Nann, S. A. Page, S. I. Penttila, W. D. Ramsay, A. Salas Bacci, S. Santra, M. Sharma, T. B. Smith, W. M. Snow, W. S. Wilburn, H. Zhu

Physics & Astronomy

High precision fundamental neutron physics experiments have been proposed for the intense pulsed spallation neutron beams at JSNS, LANSCE, and SNS to test the standard model and search for new physics. Certain systematic effects in some of these experiments have to be controlled at the few ppb level. The NPDGamma experiment, a search for the small parity-violating gamma-ray asymmetry A(gamma) in polarized cold neutron capture on parahydrogen, is one example. For the NPDGamma experiment we developed a radio-frequency resonant spin rotator to reverse the neutron polarization in a 9.5 cm x 9.5 cm pulsed cold neutron beam with high efficiency …

Metrics For Solar Wind Prediction Models: Comparison Of Empirical, Hybrid, And Physics‐Based Schemes With 8 Years Of L1 Observations, M. J. Owens, Harlan E. Spence, S. Mcgregor, W. J. Hughes, J. M. Quinn, C. N. Arge, P. Riley, J. Linker, D. Odstrcil

Physics & Astronomy

[1] Space weather effects on technological systems originate with energy carried from the Sun to the terrestrial environment by the solar wind. In this study, we present results of modeling of solar corona-heliosphere processes to predict solar wind conditions at the L1 Lagrangian point upstream of Earth. In particular we calculate performance metrics for (1) empirical, (2) hybrid empirical/physics-based, and (3) full physics-based coupled corona-heliosphere models over an 8-year period (1995–2002). L1 measurements of the radial solar wind speed are the primary basis for validation of the coronal and heliosphere models studied, though other solar wind parameters are also considered. …

Ambient Solar Wind's Effect On Icme Transit Times, A. W. Case, Harlan E. Spence, M. J. Owens, P. Riley, D. Odstrcil

Physics & Astronomy

[1] Most empirical and numerical models of Interplanetary Coronal Mass Ejection (ICME) propagation use the initial CME velocity as their primary, if not only, observational input. These models generally predict a wide spread of 1 AU transit times for ICMEs with the same initial velocity. We use a 3D coupled MHD model of the corona and heliosphere to determine the ambient solar wind's effect on the propagation of ICMEs from 30 solar radii to 1 AU. We quantitatively characterize this deceleration by the velocity of the upstream ambient solar wind. The effects of varying solar wind parameters on the ICME …

Observations Of High Frequency, Long Range Acoustic Propagation In A Harbor Environment, Michelle Weirathmueller, Thomas C. Weber, Larry A. Mayer

Center for Coastal and Ocean Mapping

The positioning and navigation of AUV's in harbor environments using underwater acoustics is complicated by shallow waters, long propagation distances, and complex oceanographic features. This paper reports on high frequency (40 kHz) acoustic measurements made in Portsmouth Harbor, NH, USA, which is an estuary containing several riverine inputs and a strong tidal flow (2+ knots). A one-way propagation experiment was conducted at the mouth of the harbor for propagation distances up to 100 water depths. Strong signatures of a variety of phenomenon were observed in the acoustic signal levels, including tidal heights and currents, turbulent mixing, and wind/wave action. The …

Inherent Length-Scales Of Periodic Solar Wind Number Density Structures, N. M. Viall, L. Kepko, Harlan E. Spence

Physics & Astronomy

[1] We present an analysis of the radial length-scales of periodic solar wind number density structures. We converted 11 years (1995–2005) of solar wind number density data into radial length series segments and Fourier analyzed them to identify all spectral peaks with radial wavelengths between 72 (116) and 900 (900) Mm for slow (fast) wind intervals. Our window length for the spectral analysis was 9072 Mm, approximately equivalent to 7 (4) h of data for the slow (fast) solar wind. We required that spectral peaks pass both an amplitude test and a harmonic F-test at the 95% confidence level simultaneously. …

Simultaneous Measurements Of Particulate And Gas-Phase Water-Soluble Organic Carbon Concentrations At Remote And Urban-Influenced Locations, C Anderson, Jack E. Dibb, Robert J. Griffin, M Bergin

Earth Sciences

The sources, sinks, and overall importance of watersoluble organic carbon (WSOC) in the atmosphere are not well understood. Although the primary historical focus has been on particulate WSOC (WSOCP), here we also present results obtained using a newly developed technique that additionally measures gas-phase water-soluble organic carbon (WSOCG). These first-of-their-kind measurements show that WSOCG can often be more than ten times larger than WSOCP at both urban and remote locations. The average fraction of WSOC residing in the gas phase (fg = WSOCG/(WSOCG + WSOCP)) at five various field sites ranged from 0.64 to 0.93, implying significant differences in WSOC …

Very Shallow Water Bathymetry Retrieval From Hyperspectral Imagery At The Virginia Coast Reserve (Vcr'07) Multi-Sensor Campaign, Charles M. Bachmann, Marcos J. Montes, Robert A. Fusina, Christopher Parrish, Jon Sellars, Alan Weidemann, Wesley Goode, C Reid Nichols, Patrick Woodward, Kevin Mcilhany, Victoria Hill, Richard Zimmerman, Daniel Korwan, Barry Truitt, A. Schwarzschild

Center for Coastal and Ocean Mapping

A number of institutions, including the Naval Research Laboratory (NRL), have developed look up tables for remote retrieval of bathymetry and in-water optical properties from hyperspectral imagery (HSI) [6]. For bathymetry retrieval, the lower limit is the very shallow water case (here defined as < 2m), a depth zone which is not well resolved by many existing bathymetric LIDAR sensors, such as SHOALS [4]. The ability to rapidly model these shallow water depths from HSI directly has potential benefits for combined HSI/LIDAR systems such as the Compact Hydrographic Airborne Rapid Total Survey (CHARTS) [10]. In this study, we focused on the validation of a near infra-red feature, corresponding to a local minimum in absorption (and therefore a local peak in reflectance), which can be correlated directly to bathymetry with a high degree of confidence. Compared to other VNIR wavelengths, this particular near-IR feature corresponds to a peak in the correlation with depth in this very shallow water regime, and this is a spectral range where reflectance depends primarily on water depth (water absorption) and bottom type, with suspended constituents playing a secondary role.

Analysis Of Aircraft And Satellite Measurements From The Intercontinental Chemical Transport Experiment (Intex-B) To Quantify Long-Range Transport Of East Asian Sulfur To Canada, Aaron Van Donkelaar, R V. Martin, W R. Leaitch, A M. Macdonald, T W. Walker, David G. Streets, Q Zhang, E J. Dunlea, Jose L. Jimenez, Jack E. Dibb, L Gregory Huey, Rodney J. Weber, M O. Andreae

Earth Sciences

We interpret a suite of satellite, aircraft, and ground-based measurements over the North Pacific Ocean and western North America during April–May 2006 as part of the Intercontinental Chemical Transport Experiment Phase B (INTEX-B) campaign to understand the implications of long-range transport of East Asian emissions to North America. The Canadian component of INTEX-B included 33 vertical profiles from a Cessna 207 aircraft equipped with an aerosol mass spectrometer. Long-range transport of organic aerosols was insignificant, contrary to expectations. Measured sulfate plumes in the free troposphere over British Columbia exceeded 2 μg/m3. We update the global anthropogenic emission inventory in a …

Local Anthropogenic Impact On Particulate Elemental Carbon Concentrations At Summit, Greenland, Gayle S.W. Hagler, M Bergin, E A. Smith, M Town, Jack E. Dibb

Earth Sciences

Summit, Greenland is a remote Arctic research station allowing for field measurements at the highest point of the Greenland Ice Sheet. Due to the current reliance on diesel generators for electricity at Summit, unavoidable local emissions are a potential contamination threat to the measurement of combustion-related species in the air and snow. The effect of fossil-fuel combustion on particulate elemental carbon (EC) is assessed by a combination of ambient measurements (∼1 km from the main camp), a series of snow pits, and Gaussian plume modeling. Ambient measurements indicate that the air directly downwind of the research station generators experiences particulate …

U.S. Law Of The Sea Cruise To Map The Foot Of The Slope Of The Northeast U.S. Atlantic Continental Margin: Leg 6, Brian R. Calder, James V. Gardner

Center for Coastal and Ocean Mapping

U.S. Law of the Sea Cruise to Map the Foot of the Slope of the Northeast U.S. Atlantic Continental Margin: Leg 6

Cruise KNOX17RR

May 1 – 31, 2008

Ft. Lauderdale, FL to Woods Hole, MA

From The Arctic To The Tropics: The U.S. Unclos Bathymetric Mapping Program, James V. Gardner, Larry A. Mayer, Andy Armstrong

Center for Coastal and Ocean Mapping

Since CHC2006, the University of New Hampshire’s Center for Coastal & Ocean Mapping/Joint Hydrographic Center has mapped with multibeam, the bathymetry of an additional ~220,000 km2 of seafloor in areas as diverse as the Arctic, the Northern Marianas of the western Pacific and the Gulf of Mexico. The mapping supports any potential U.S. submission for of extended continental shelves under Article 76 of the United Nations Convention of the Law of the Sea. Consequently, the mapping has concentrated on capturing the complete extent of the 2500-m isobath and the zone where the Article 76-defined foot of the slope exists. In …

Environmental Response Management Application, Michele Jacobi, Nancy E. Kinner, Rob Braswell, Kurt Schwehr, Kimberly S. Newman, Amy A. Merten

Center for Coastal and Ocean Mapping

The Coastal Response Research Center (CRRC), a partnership between the University of New Hampshire (UNH) and NOAA's Office of Response and Restoration (ORR), is leading an effort to develop a data platform capable of interfacing both static and real-time data sets accessible simultaneously to a command post and assets in the field with an open source internet mapping server. The Environmental Response Management Application (ERMA™) is designed to give responders and decision makers ready access to geographically specific data useful during spill planning/drills, incident response, damage assessment and site restoration. In addition to oil spill and chemical release response, this …

An Event Study To Provide Validation Of Ting And Cmit Geomagnetic Middle-Latitude Electron Densities At The F2 Peak, A. G. Burns, W. Wang, M. Wiltberger, S. C. Soloman, Harlan E. Spence, T. L. Killeen, R. E. Lopez, J. E. Landivar

Physics & Astronomy

[1] The coupled thermosphere-ionosphere magnetosphere (CMIT) model and the Thermosphere Ionosphere Nested Grid (TING) model have been run to simulate the 15 May 1997 interplanetary coronal mass ejection's (ICME) effects on the Earth's ionosphere and thermosphere. Comparisons were made between these model runs, the IRI-2007 model, and geomagnetic middle-latitude ionosonde data (NmF2) from the World Data Center to determine how well the models simulated the event and to understand the causes of model-data disagreement. The following conclusions were drawn from this study: (1) skill scores were more often negative than positive on average; (2) the best and the worst skill …

Iho S-100: The New Hydrographic Geospatial Standard For Marine Data And Information, Robert Ward, Lee Alexander, Barrie Greenslade, Anthony Pharaoh

Center for Coastal and Ocean Mapping

The International Hydrographic Organization (IHO) is an intergovernmental consultative and technical organization established in 1921 to support the safety of navigation, and to contribute to the protection of the marine environment. One of its primary roles is to establish and maintain appropriate standards to assist in the proper and efficient use of hydrographic data and information. This paper describes the new IHO Geospatial Standard for Hydrographic Data to be known as S-100, together with the Geospatial Information Infrastructure (GII) that is in the course of development and implementation by the IHO. In both cases, details have yet to be finalised …

The Impact Of Local Sources And Long-Range Transport On Aerosol Properties Over The Northeast U.S. Region During Intex-Na, K L. Thornhill, Gao Chen, Jack E. Dibb, C. Jordan, Ali Omar, E L. Winstead, Greg Schuster, A D. Clarke, Cameron Mcnaughton, Eric Scheuer, D R. Blake, Glen Sachse, L Gregory Huey, H B. Singh, Bruce E. Anderson

Earth Sciences

We use data collected aboard the NASA DC-8 aircraft during the summer 2004, Intercontinental Transport and Chemical Evolution Experiment over North America (INTEX-NA) field campaign to examine the origin, composition, physical and optical properties of aerosols within air masses sampled over and downwind of the northeastern U.S. We note that aerosol concentrations within the region exhibited steep vertical gradients and significant variability in both time and space. An examination of air mass chemical signatures and backward trajectories indicates that transport from four, significantly different source regions contributed to the variability: the subtropical Atlantic Ocean (AO); the U.S. west coast and …

A Compton Telescope For Remote Location And Identification Of Radioactive Material, James M. Ryan, Justin Baker, John R. Macri, Mark L. Mcconnell, Richard Carande

Space Science Center

The spare detectors from NASA Compton Gamma-Ray Observatory COMPTEL instrument have been reconfigured to demonstrate the capability at ground level to remotely locate and identify sources of g radiation or the movement of material that might shield γ-ray sources. The Gamma-Ray Experimental Telescope Assembly (GRETA) employs two 28 cm diameter scintillation detectors separated by 81 cm: one 8.5 cm thick liquid scintillator detector and one 7.5 cm thick NaI(Tl) detector. The assembly electronics and real-time data acquisition system measures the energy deposits and time-of- flight for each coincident detection and compiles histograms of total energy and incident angle as computed …

Development And Performance Of The Fast Neutron Imaging Telescope For Snm Detection, James M. Ryan, U Bravar, E O. Fluckiger, John R. Macri, Mark L. Mcconnell, B Pirard, R S. Woolf

Space Science Center

FNIT (the Fast Neutron Imaging Telescope), a detector with both imaging and energy measurement capabilities, sensitive to neutrons in the range 0.8-20 MeV, was initially conceived to study solar neutrons as a candidate design for the Inner Heliosphere Sentinel (IHS) spacecraft of NASA's Solar Sentinels program and successively reconfigured to locate fission neutron sources. By accurately identifying the position of the source with imaging techniques and reconstructing the Watt spectrum of fission neutrons, FNIT can detect samples of special nuclear material (SNM), including heavily shielded and masked ones. The detection principle is based on multiple elastic neutron-proton scatterings in organic …

Factors Influencing The Large-Scale Distribution Of Hg° In The Mexico City Area And Over The North Pacific, Robert W. Talbot, Huiting Mao, Jack E. Dibb, M A. Avery, E V. Browell, G W. Sachse, S Vay, D R. Blake, L Gregory Huey, H Fuelberg

Earth Sciences

Gas-phase elemental mercury (Hg°) was measured aboard the NASA DC-8 aircraft during the Intercontinental Chemical Transport Experiment Phase B (INTEX-B) campaign in spring 2006. Flights were conducted around Mexico City and on two subsequent deployments over the North Pacific based out of Honolulu, Hawaii and Anchorage, Alaska. Data obtained from 0.15–12 km altitude showed that Hg° exhibited a relatively constant vertical profile centered around 100 ppqv. Highly concentrated pollution plumes emanating from the Mexico City urban agglomeration revealed that mixing ratios of Hg° as large as 500 ppqv were related to combustion tracers such as CO, but not SO2 which …

A Quantitative Assessment Of Empirical Magnetic Field Models At Geosynchronous Orbit During Magnetic Storms, Chia-Lin L. Huang, Harlan E. Spence, H. J. Singer, N. A. Tsyganenko

Physics & Astronomy

[1] We evaluate the performance of recent empirical magnetic field models (Tsyganenko, 1996, 2002a, 2002b; Tsyganenko and Sitnov, 2005, hereafter referred to as T96, T02 and TS05, respectively) during magnetic storm times including both pre- and post-storm intervals. The model outputs are compared with GOES observations of the magnetic field at geosynchronous orbit. In the case of a major magnetic storm, the T96 and T02 models predict anomalously strong negative Bz at geostationary orbit on the nightside due to input values exceeding the model limits, whereas a comprehensive magnetic field data survey using GOES does not support that prediction. On …