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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Southern Maine, New Hampshire, And Northern Massachusetts Continental Shelf Geophysical Database: 2022 Field Campaign – Grain Size Data, Station Summaries, And Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Michael Bogonko Feb 2024

Southern Maine, New Hampshire, And Northern Massachusetts Continental Shelf Geophysical Database: 2022 Field Campaign – Grain Size Data, Station Summaries, And Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Michael Bogonko

Data Catalog

Presented in this data report are the geophysical data collected during a major field campaign in 2022, with the purpose of obtaining ground truth for the expansion and improvement of high-resolution surficial geology maps of the western Gulf of Maine (WGOM) and for the description of reference sites developed for future evaluations of acoustic systems (Ward et al., 2021a; 2021b). Data from the UNH Ocean Engineering 972 Hydrographic Field Course classes in 2021 and 2022 are also included. This expansion of the geophysical database is being used to verify seafloor classifications in previously mapped areas that lack sufficient data, and …


Controls On Buffering And Coastal Acidification In A Temperate Estuary, Christopher W. Hunt, Joseph Salisbury, Douglas Vandemark Apr 2022

Controls On Buffering And Coastal Acidification In A Temperate Estuary, Christopher W. Hunt, Joseph Salisbury, Douglas Vandemark

Faculty Publications

Estuaries may be uniquely susceptible to the combined acidification pressures of atmospherically driven ocean acidification (OA), biologically driven CO2 inputs from the estuary itself, and terrestrially derived freshwater inputs. This study utilized continuous measurements of total alkalinity (TA) and the partial pressure of carbon dioxide (pCO2) from the mouth of Great Bay, a temperate northeastern U.S. estuary, to examine the potential influences of endmember mixing and biogeochemical transformation upon estuary buffering capacity (β–H). Observations were collected hourly over 28 months representing all seasons between May 2016 and December 2019. Results indicated that endmember mixing explained most of the observed variability …


New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps And Sediment Grain Size Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison Mar 2022

New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps And Sediment Grain Size Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison

Data Catalog

The “New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps and Sediment Grain Size Data” consists of high-resolution surficial geology maps of the continental shelf off New Hampshire to Jeffreys Ledge in the Western Guff of Maine (WGOM) and supporting sediment grain size information. The surficial geology maps cover ~3,250 km2 (Figure 1). The maps depict three different classifications based on the Coastal and Marine Ecological Classification Standards (CMECS; FGDC, 2012): Geoforms (major morphologic or physiographic features; Figure 2; Table 1), Geologic Substrate Subclass (Figure 3; Table 2), and Geologic Substrate Group (Figure 4; Table 2). The maps are …


Variability Of Usa East Coast Surface Total Alkalinity Distributions Revealed By Automated Instrument Measurements, Christopher W. Hunt, Joseph Salisbury, Douglas Vandemark, Steffen Aßmann, Christopher Melrose, Rik Wanninkhof, Kumiko Azetsu-Scott May 2021

Variability Of Usa East Coast Surface Total Alkalinity Distributions Revealed By Automated Instrument Measurements, Christopher W. Hunt, Joseph Salisbury, Douglas Vandemark, Steffen Aßmann, Christopher Melrose, Rik Wanninkhof, Kumiko Azetsu-Scott

Faculty Publications

Seawater total alkalinity (TA) is one important determinant used to monitor the ocean carbon cycle, whose spatial distributions have previously been characterized along the United States East Coast via discrete bottle samples. Using these data, several regional models for TA retrievals based on practical salinity (S) have been developed. Broad-scale seasonal or interannual variations, however, are not well resolved in these models and existing data are highly seasonally biased. This study reports findings from the first long duration deployment of a new, commercially available TA titrator aboard a research vessel and the continuous underway surface TA measurements produced. The …


Surficial Geology Of The Continental Shelf Off New Hampshire: Morphologic Features And Surficial Sediment, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani, Rachel C. Morrison Jan 2021

Surficial Geology Of The Continental Shelf Off New Hampshire: Morphologic Features And Surficial Sediment, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani, Rachel C. Morrison

Center for Coastal and Ocean Mapping

The continental shelf off New Hampshire (NH) in the Western Gulf of Maine (WGOM) is extremely complex and includes extensive bedrock outcrops, marine-modified glacial deposits, marine-formed shoals, seafloor plains, and associated features that are composed of a range of sediment types from mud to gravel. Furthermore, the physiography and composition of the seafloor frequently changes dramatically over relatively short distances (tens of meters). The complexity of the WGOM seafloor results from the interplay of glaciations, sea-level fluctuations, and marine processes (waves and currents). High-resolution multibeam echosounder (MBES) bathymetry and backscatter surveys, along with ground truth consisting of archived seismic reflection …


New Hampshire Continental Shelf Geophysical Database: 2002-2005 Jeffreys Ledge Field Campaign – Seafloor Photographs And Sediment Data, Larry G. Ward, Raymond E. Grizzle, Rachel C. Morrison Jan 2021

New Hampshire Continental Shelf Geophysical Database: 2002-2005 Jeffreys Ledge Field Campaign – Seafloor Photographs And Sediment Data, Larry G. Ward, Raymond E. Grizzle, Rachel C. Morrison

Data Catalog

Jeffreys Ledge is a major physiographic feature in the western Gulf of Maine (WGOM) located ~50 km off the coast of New Hampshire, although coming within ~10 km of shore by Cape Ann, Massachusetts. Jeffreys Ledge rises up as much as ~150 m from the seafloor of the adjacent basins (i.e., Scantum Basin or Wilkinson Basin) to depths less than 50 m on the ridge surface. The ridge extends over 100 km along its north-northeast to south-southwest axes while generally only being 5 to 10 km in width (~20 km maximum). Jeffreys Ledge and the surrounding region, like many features …


New Hampshire Continental Shelf Geophysical Database: 2012-2013 Newbex Field Campaign – Seafloor Photographs And Sediment Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison Jan 2021

New Hampshire Continental Shelf Geophysical Database: 2012-2013 Newbex Field Campaign – Seafloor Photographs And Sediment Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison

Data Catalog

An approximately 4.5 km transect running from lower Portsmouth Harbor seaward onto the inner continental shelf was established to serve as the field site for the Newcastle Backscatter Experiment (NEWBEX). Acoustic backscatter measurements were made along the transect to examine relationships between backscatter and seafloor properties. This transect takes advantage of the diversity and heterogeneity of bottom types in lower Portsmouth Harbor and approach. In support of NEWBEX, a field campaign was undertaken to describe the sedimentologic characteristics of the seafloor along the transect. A total of five cruises were carried out approximately seasonally on November 26, 2012 and June …


New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy Jan 2021

New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs” was developed by the University of New Hampshire (UNH) Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). The field campaign was conducted to provide ground truth for surficial geology maps for the continental shelf off New Hampshire (NH) and focused on the inner shelf between the coast and the Isles of Shoals. Station locations were chosen where high-resolution bathymetry was available, including multibeam echosounder (MBES) surveys conducted by the UNH CCOM/JHC Hydrographic Field Course (Ocean Engineering 972), MBES surveys by the NOAA National Ocean Service (NOS), …


New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor And Sample Photographs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy Jan 2021

New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor And Sample Photographs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign - Seafloor and Sample Photographs and Sediment Data " contains photographs of the seafloor from sampling locations, photographs of the sediment samples, and grain size data from a major field campaign conducted in 2016- 2017 and from the UNH Ocean Engineering 972 Hydrographic Field Course classes in 2012, 2014, and 2018. In total, sixteen one-day cruises provided 150 samples for grain size analysis. The database provides complete descriptions for each sample including identification, station and sample characteristics, sediment classifications, grain size statistics, and grain size distribution. Presented here are tables …


Northeast Bathymetry And Backscatter Compilation: Western Gulf Of Maine, Southern New England, And Long Island Sound, Larry G. Ward, Paul Johnson, Michael Bogonko, Zachary S. Mcavoy, Rachel C. Morrison Jan 2021

Northeast Bathymetry And Backscatter Compilation: Western Gulf Of Maine, Southern New England, And Long Island Sound, Larry G. Ward, Paul Johnson, Michael Bogonko, Zachary S. Mcavoy, Rachel C. Morrison

Center for Coastal and Ocean Mapping

High-resolution bathymetry is critical for mapping the surficial geology of the seafloor, identifying critical habitats, and assessing marine mineral resources such as sand and gravel. In 2016, a high-resolution bathymetry map was developed for the western Gulf of Maine (WGOM) utilizing all available multibeam echosounder (MBES) surveys, as well as several older extant surveys (Western Gulf of Maine Bathymetry and Backscatter Synthesis, Ward et al., 2016). As part of that effort, a backscatter mosaic also was developed for a subset of the MBES surveys. The backscatter synthesis did not include all of the MBES surveys due to low quality of …


Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani Jan 2021

Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Center for Coastal and Ocean Mapping

During this study, the twenty-three vibracores taken in 1984 and 1988 were reexamined, original descriptions verified and significantly expanded, and the cores sampled to provide complete grain size data (i.e. the original sediment grain size analyses were limited). The vibracores were grouped by location with respect to major physiographic features (geoforms) or surficial sediment type including Offshore Marine-Modified Glacial Features (Drumlins and Lodgement Till Deposits), Northern Sand Body, Isles of Shoals, Nearshore Marine-Modified Glacial Features (Eskers and Drumlins), Nearshore Sheet Sand, and Offshore Seafloor Plain.

The Northern Sand Body (NSB), located near the Isles of Shoals ~10 km from shore, …


Mendums Pond 2021 Water Quality Highlight Report, Robert Craycraft, Amanda Mcquaid Jan 2021

Mendums Pond 2021 Water Quality Highlight Report, Robert Craycraft, Amanda Mcquaid

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Mendums Pond (Barrington, NH) for 2021.


Are New Hampshire’S Winters Warming? Yes, But Fewer Than Half Of State Residents Recognize The Trend, Lawrence C. Hamilton, Elizabeth Burakowski Feb 2020

Are New Hampshire’S Winters Warming? Yes, But Fewer Than Half Of State Residents Recognize The Trend, Lawrence C. Hamilton, Elizabeth Burakowski

The Carsey School of Public Policy at the Scholars' Repository

In this brief, authors Elizabeth Burakowski and Lawrence Hamilton review some basic evidence about winter warming in New Hampshire, explore to what extent state residents are aware of this trend, and ask who is aware, in terms of characteristics such as age, education, or participation in winter sports. Results from two statewide surveys find limited awareness of the trend overall, and no significant differences by age, education, or winter sports participation. Instead, perceptions of this winter trend depend on political identity: conservatives are much less likely than other groups to recognize that warming has occurred.


Economic Contributions Of Winter Sports In A Changing Climate, Hagenstad Consulting, Inc., Elizabeth Burakowski, Rebecca Hill Feb 2018

Economic Contributions Of Winter Sports In A Changing Climate, Hagenstad Consulting, Inc., Elizabeth Burakowski, Rebecca Hill

Earth Systems Research Center

In mountain towns across the United States that rely on winter tourism, snow is

currency. For snow lovers and the winter sports industry, predictions of a future with

warmer winters, reduced snowfall, and shorter snow seasons is inspiring them to

innovate, increase their own efforts to address emissions, and speak publicly on the

urgent need for action.

This report examines the economic contribution of winter snow sports tourism to

U.S. national and state-level economies. In a 2012 analysis, Protect Our Winters and

the Natural Resources Defense Council found that the winter sports tourism industry

generates $12.2 billion and 23 million …


Preparing For A Northwest Passage: A Workshop On The Role Of New England In Navigating The New Arctic, Katharine A. Duderstadt, Catherine M. Ashcraft, Jennifer F. Brewer, Elizabeth Burakowski, Jaed M. Coffin, Jack E. Dibb, Lawrence C. Hamilton, Nancy E. Kinner, Larry A. Mayer, Jennifer L. Miksis-Olds, Joseph Salisbury, Kerri D. Seger, Ruth K. Varner, Cameron P. Wake Jan 2018

Preparing For A Northwest Passage: A Workshop On The Role Of New England In Navigating The New Arctic, Katharine A. Duderstadt, Catherine M. Ashcraft, Jennifer F. Brewer, Elizabeth Burakowski, Jaed M. Coffin, Jack E. Dibb, Lawrence C. Hamilton, Nancy E. Kinner, Larry A. Mayer, Jennifer L. Miksis-Olds, Joseph Salisbury, Kerri D. Seger, Ruth K. Varner, Cameron P. Wake

Earth Systems Research Center

Preparing for a Northwest Passage: A Workshop on the Role of New England in Navigating the New Arctic (March 25 - 27, 2018 -- The University of New Hampshire) paired two of NSF's 10 Big Ideas: Navigating the New Arctic and Growing Convergence Research at NSF. During this event, participants assessed economic, environmental, and social impacts of Arctic change on New England and established convergence research initiatives to prepare for, adapt to, and respond to these effects. Shipping routes through an ice-free Northwest Passage in combination with modifications to ocean circulation and regional climate patterns linked to Arctic ice melt …


Integrated Analysis Of The Value Of Wetland Services In Coastal Adaptation; Methodology And Case Study Of Hampton-Seabrook Estuary, New Hampshire, Paul Kirshen, Semra Aytur, David M. Burdick, Diane Foster, Tom Lippmann, Ellen Douglas, Sydney Nick, Chris Watson Jan 2018

Integrated Analysis Of The Value Of Wetland Services In Coastal Adaptation; Methodology And Case Study Of Hampton-Seabrook Estuary, New Hampshire, Paul Kirshen, Semra Aytur, David M. Burdick, Diane Foster, Tom Lippmann, Ellen Douglas, Sydney Nick, Chris Watson

Jackson Estuarine Laboratory

The present impacts from coastal storms and high tides grow significantly over time due to SLR even over the relatively short period to 2060. Hydrodynamic model simulations of storm surge with and without sea level rise scenarios show that although flooding and inundation increases with increasing subtidal forcing and higher sea level, dissipation of the tide and storm surge in the estuary channel somewhat limits the maximum inundation that might otherwise be expected in the back marsh areas. The estuary is dominated by high marsh, which lies high in the intertidal zone and by 2060 it will convert to mostly …


Flooding And Inundation Modeling In The Great Bay Estuary, Anna E. Simpson Jan 2017

Flooding And Inundation Modeling In The Great Bay Estuary, Anna E. Simpson

Honors Theses and Capstones

As part of this research, FVCOM, a finite-volume coastal ocean numerical hydrodynamic model (Chen, et al., 2003), was implemented into the Great Bay estuary. FVCOM is one of several community models that have been developed for coastal regions, and was selected because it utilizes an unstructured grid to discretize the model domain. The unstructured grid provides the ability to have fine scale resolution near the boundary or coastline and decreased resolution away from the boundary where the flow field is less complicated, resulting in greatly reduced computational expense in less dynamic regions allowing model runs to be completed in …


Spectral Aerosol Extinction (Spex): A New Instrument For In Situ Ambient Aerosol Extinction Measurements Across The Uv/Visible Wavelength Range, C. E. Jordan, B E. Anderson, A J. Beyersdorf, C A. Corr, Jack E. Dibb, Margaret E. Greenslade, R F. Martin, R H. Moore, Eric Scheuer, M A. Shook, Kenn L. Thornhill, D Troop, Luke D. Ziemba, E L. Winstead Nov 2015

Spectral Aerosol Extinction (Spex): A New Instrument For In Situ Ambient Aerosol Extinction Measurements Across The Uv/Visible Wavelength Range, C. E. Jordan, B E. Anderson, A J. Beyersdorf, C A. Corr, Jack E. Dibb, Margaret E. Greenslade, R F. Martin, R H. Moore, Eric Scheuer, M A. Shook, Kenn L. Thornhill, D Troop, Luke D. Ziemba, E L. Winstead

Earth Sciences

We introduce a new instrument for the measurement of in situ ambient aerosol extinction over the 300– 700 nm wavelength range, the spectral aerosol extinction (SpEx) instrument. This measurement capability is envisioned to complement existing in situ instrumentation, allowing for simultaneous measurement of the evolution of aerosol optical, chemical, and physical characteristics in the ambient environment. In this work, a detailed description of the instrument is provided along with characterization tests performed in the laboratory. Measured spectra of NO2 and polystyrene latex spheres (PSLs) agreed well with theoretical calculations. Good agreement was also found with simultaneous aerosol extinction measurements at …


Neither Dust Nor Black Carbon Causing Apparent Albedo Decline In Greenland's Dry Snow Zone: Implications For Modis C5 Surface Reflectance, Chris Polashenski, Jack E. Dibb, Mark G. Flanner, Justin Y. Chen, Zoe R. Courville, Alexandra M. Lai, James J. Schauer, Martin M. Shafer, Mike Bergin Nov 2015

Neither Dust Nor Black Carbon Causing Apparent Albedo Decline In Greenland's Dry Snow Zone: Implications For Modis C5 Surface Reflectance, Chris Polashenski, Jack E. Dibb, Mark G. Flanner, Justin Y. Chen, Zoe R. Courville, Alexandra M. Lai, James J. Schauer, Martin M. Shafer, Mike Bergin

Earth Sciences

Remote sensing observations suggest Greenland ice sheet (GrIS) albedo has declined since 2001, even in the dry snow zone. We seek to explain the apparent dry snow albedo decline. We analyze samples representing 2012–2014 snowfall across NW Greenland for black carbon and dust light-absorbing impurities (LAI) and model their impacts on snow albedo. Albedo reductions due to LAI are small, averaging 0.003, with episodic enhancements resulting in reductions of 0.01–0.02. No significant increase in black carbon or dust concentrations relative to recent decades is found. Enhanced deposition of LAI is not, therefore, causing significant dry snow albedo reduction or driving …


Observations Of Backscatter From Sand And Gravel Seafloors Between 170-250 Khz, Thomas C. Weber, Larry G. Ward Oct 2015

Observations Of Backscatter From Sand And Gravel Seafloors Between 170-250 Khz, Thomas C. Weber, Larry G. Ward

Center for Coastal and Ocean Mapping

Interpreting observations of frequency-dependence in backscatter from the seafloor offers many challenges, either because multiple frequencies are used for different observations that will later be merged or simply because seafloor scattering models are not well-understood above 100 kHz. Hindering the understanding of these observations is the paucity of reported, calibratedacoustic measurements above 100 kHz. This manuscript seeks to help elucidate the linkages between seafloor properties and frequency-dependent seafloor backscatter by describing observations of backscatter collected from sand, gravel, and bedrock seafloors at frequencies between 170 and 250 kHz and at a grazing angle of 45°. Overall, the frequency dependence appeared …


Initiatives In Using Crowdsourcing, Satellite Derived Bathymetry, And Other Non-Traditional Hydrographic/Bathymetric Measurements, Anthony Klemm, Shachak Pe'eri, John Nyberg Oct 2015

Initiatives In Using Crowdsourcing, Satellite Derived Bathymetry, And Other Non-Traditional Hydrographic/Bathymetric Measurements, Anthony Klemm, Shachak Pe'eri, John Nyberg

Center for Coastal and Ocean Mapping

No abstract provided.


Chart Adequacy: Workshop And Gebco Training, Limor Gur-Arieh, Yusoff Kamaruddin, Amon Kimeli, Anthony Klemm, Hirokazu Kurita, Shachak Pe'eri, Indra Budi Prasetyawan, Jae-Young Roh, Jaya Roperez, Nilupa Samarakoon, Jaqueline Sydenham, Maxlimer Vallee, Rochelle A. Wigley Oct 2015

Chart Adequacy: Workshop And Gebco Training, Limor Gur-Arieh, Yusoff Kamaruddin, Amon Kimeli, Anthony Klemm, Hirokazu Kurita, Shachak Pe'eri, Indra Budi Prasetyawan, Jae-Young Roh, Jaya Roperez, Nilupa Samarakoon, Jaqueline Sydenham, Maxlimer Vallee, Rochelle A. Wigley

Center for Coastal and Ocean Mapping

In July, 2015 the first NOAA Chart Adequacy Workshop was held in Silver Spring, Maryland, USA. Following a three-day workshop (14th to 16th July, 2015), four Nippon Foundation GEBCO students stayed at NOAA for an additional 10-day training at Office of Coast Survey’s Marine Chart Division. The key objective of the NOAA Chart Adequacy Workshop was to demonstrate techniques to evaluate the suitability of nautical chart products using chart quality information and publicly-available information. The attendees were cartographers, hydrographers and potential chart producers from hydrographic offices and government agencies around the world. The nations of the participants in the workshop …


Reconnaissance Surveying Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Michael Gonsalves Oct 2015

Reconnaissance Surveying Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Michael Gonsalves

Center for Coastal and Ocean Mapping

False Pass, AK, USA, is the eastern-most passage through the Aleutian Islands between the Bering Sea and the Pacific Ocean and provides a passage for small to mid-size vessels. The passage is considered an alternative route to Unimak Pass, AK for vessels from mainland Alaska and is estimated to be shorter by 160 to 240km. False Pass is closed every winter due to sea-ice cover that freezes the inlet system around OctoberNovember and melts only towards the spring (around March). As a result, the soft sediment of the seafloor contains mud and sand that may change the path of the …


Brown Carbon Aerosol In The North American Continental Troposphere: Sources, Abundance, And Radiative Forcing, J. Liu, Eric Scheuer, Jack E. Dibb, G S. Diskin, L D. Ziemba, K L. Thornhill, B E. Anderson, A Whisthaler, T Mikoviny, J J. Devi, M Bergin, A E. Perring, M Z. Markovic, J P. Schwarz, P Campuzano-Jost, D A. Day, J L. Jimenez, R J. Weber Jul 2015

Brown Carbon Aerosol In The North American Continental Troposphere: Sources, Abundance, And Radiative Forcing, J. Liu, Eric Scheuer, Jack E. Dibb, G S. Diskin, L D. Ziemba, K L. Thornhill, B E. Anderson, A Whisthaler, T Mikoviny, J J. Devi, M Bergin, A E. Perring, M Z. Markovic, J P. Schwarz, P Campuzano-Jost, D A. Day, J L. Jimenez, R J. Weber

Earth Sciences

Chemical components of organic aerosol (OA) selectively absorb light at short wavelengths. In this study, the prevalence, sources, and optical importance of this so called brown carbon (BrC) aerosol component are investigated throughout the North American continental tropospheric column during a summer of extensive biomass burning. Spectrophotometric absorption measurements on extracts of bulk aerosol samples collected from an aircraft over the central USA were analyzed to directly quantify BrC abundance. BrC was found to be prevalent throughout the 1 to 12 km altitude measurement range, with dramatic enhancements in biomass-burning plumes. BrC to black carbon (BC) ratios, under background tropospheric …


Modeling Impacts Of Changes In Temperature And Water Table On C Gas Fluxes In An Alaskan Peatland, Jia Deng, Changsheng Li, Steve Frolking Jul 2015

Modeling Impacts Of Changes In Temperature And Water Table On C Gas Fluxes In An Alaskan Peatland, Jia Deng, Changsheng Li, Steve Frolking

Earth Sciences

Northern peatlands have accumulated a large amount of organic carbon (C) in their thick peat profile. Climate change and associated variations in soil environments are expected to have significant impacts on the C balance of these ecosystems, but the magnitude is still highly uncertain. Verifying and understanding the influences of changes in environmental factors on C gas fluxes in biogeochemical models are essential for forecasting feedbacks between C gas fluxes and climate change. In this study, we applied a biogeochemical model, DeNitrification-DeComposition (DNDC), to assess impacts of air temperature (TA) and water table (WT) on C gas fluxes …


The Polarcat Model Intercomparison Project (Polmip): Overview And Evaluation With Observations, L K. Emmons, S R. Arnold, S A. Monks, V Huijnen, S Tilmes, K S. Law, J L. Thomas, J C. Raut, I Bouarar, S Turquety, Y Long, B Duncan, S Steenrod, S Strode, J Flemming, J Mao, J Langner, A M. Thompson, D Tarasick, E C. Apel, D R. Blake, Robert C. Cohen, Jack E. Dibb, Glenn Diskin, A Fried, S R. Hall, L Gregory Huey, Andrew Weinheimer, Armin Wisthaler, Tomas Mikoviny, J Nowak, Jeff Peischl, J M. Roberts, Thomas B. Ryerson, C Warneke, D Helmig Jun 2015

The Polarcat Model Intercomparison Project (Polmip): Overview And Evaluation With Observations, L K. Emmons, S R. Arnold, S A. Monks, V Huijnen, S Tilmes, K S. Law, J L. Thomas, J C. Raut, I Bouarar, S Turquety, Y Long, B Duncan, S Steenrod, S Strode, J Flemming, J Mao, J Langner, A M. Thompson, D Tarasick, E C. Apel, D R. Blake, Robert C. Cohen, Jack E. Dibb, Glenn Diskin, A Fried, S R. Hall, L Gregory Huey, Andrew Weinheimer, Armin Wisthaler, Tomas Mikoviny, J Nowak, Jeff Peischl, J M. Roberts, Thomas B. Ryerson, C Warneke, D Helmig

Earth Sciences

A model intercomparison activity was inspired by the large suite of observations of atmospheric composition made during the International Polar Year (2008) in the Arctic. Nine global and two regional chemical transport models participated in this intercomparison and performed simulations for 2008 using a common emissions inventory to assess the differences in model chemistry and transport schemes. This paper summarizes the models and compares their simulations of ozone and its precursors and presents an evaluation of the simulations using a variety of surface, balloon, aircraft and satellite observations. Each type of measurement has some limitations in spatial or temporal coverage …


Revealing Important Nocturnal And Day-To-Day Variations In Fire Smoke Emissions Through A Multiplatform Inversion, Pablo E. Saide, David A. Peterson, Arlindo Da Silva, Bruce Anderson, Luke D. Ziemba, Glenn Diskin, Glen Sachse, Jonathan Hair, Carolyn Butler, Marta Fenn, Jose L. Jimenez, Pedro Campuzano-Jost, Anne E. Perring, Joshua P. Schwarz, Milos Z. Markovic, Phil Russell, Jens Redemann, Yohei Shinozuka, David G. Streets, Fang Yan, Jack E. Dibb, Robert Yokelson, O Brian Toon, Edward Hyer, Gregory R. Carmichael Jun 2015

Revealing Important Nocturnal And Day-To-Day Variations In Fire Smoke Emissions Through A Multiplatform Inversion, Pablo E. Saide, David A. Peterson, Arlindo Da Silva, Bruce Anderson, Luke D. Ziemba, Glenn Diskin, Glen Sachse, Jonathan Hair, Carolyn Butler, Marta Fenn, Jose L. Jimenez, Pedro Campuzano-Jost, Anne E. Perring, Joshua P. Schwarz, Milos Z. Markovic, Phil Russell, Jens Redemann, Yohei Shinozuka, David G. Streets, Fang Yan, Jack E. Dibb, Robert Yokelson, O Brian Toon, Edward Hyer, Gregory R. Carmichael

Earth Sciences

We couple airborne, ground-based, and satellite observations; conduct regional simulations; and develop and apply an inversion technique to constrain hourly smoke emissions from the Rim Fire, the third largest observed in California, USA. Emissions constrained with multiplatform data show notable nocturnal enhancements (sometimes over a factor of 20), correlate better with daily burned area data, and are a factor of 2-4 higher than a priori estimates, highlighting the need for improved characterization of diurnal profiles and day-to-day variability when modeling extreme fires. Constraining only with satellite data results in smaller enhancements mainly due to missing retrievals near the emissions source, …


Evolution Of Brown Carbon In Wildfire Plumes, Haviland Forrister, Jiumeng Liu, Jack E. Dibb, Eric Scheuer, Luke D. Ziemba, Kenn L. Thornhill, Bruce Anderson, Glenn Diskin, Anne E. Perring, Joshua P. Schwarz, Pedro Campuzano-Jost, Douglas A. Day, Brett B. Palm, Jose L. Jimenez, Athanasios Nenes, Rodney J. Weber Jun 2015

Evolution Of Brown Carbon In Wildfire Plumes, Haviland Forrister, Jiumeng Liu, Jack E. Dibb, Eric Scheuer, Luke D. Ziemba, Kenn L. Thornhill, Bruce Anderson, Glenn Diskin, Anne E. Perring, Joshua P. Schwarz, Pedro Campuzano-Jost, Douglas A. Day, Brett B. Palm, Jose L. Jimenez, Athanasios Nenes, Rodney J. Weber

Earth Sciences

Particulate brown carbon (BrC) in the atmosphere absorbs light at subvisible wavelengths and has poorly constrained but potentially large climate forcing impacts. BrC from biomass burning has virtually unknown lifecycle and atmospheric stability. Here, BrC emitted from intense wildfires was measured in plumes transported over 2 days from two main fires, during the 2013 NASA SEAC4RS mission. Concurrent measurements of organic aerosol (OA) and black carbon (BC) mass concentration, BC coating thickness, absorption Ångström exponent, and OA oxidation state reveal that the initial BrC emitted from the fires was largely unstable. Using back trajectories to estimate the transport time indicates …


Nautical Chart Adequacy Evaluation Using Publicly-Available Data, Anthony Klemm, Shachak Pe'eri, Ricardo Freire, John Nyberg, Shep M. Smith Lt Mar 2015

Nautical Chart Adequacy Evaluation Using Publicly-Available Data, Anthony Klemm, Shachak Pe'eri, Ricardo Freire, John Nyberg, Shep M. Smith Lt

Center for Coastal and Ocean Mapping

The International Hydrographic Office (IHO) C-55 publication communicates the need to improve the collection, quality and availability of hydrographic data world-wide, while also monitoring and rectifying possible deficiencies and shortcomings that are presented on the chart. This task of evaluating the adequacy of nautical chart products poses a challenge to many national hydrographic offices. This stems from the dearth of readily available spatial information: namely, the lack of reliable and accessible vessel traffic data, and little means to assess the changing nature of both near-shore bathymetry and shoreline in a simple and reliable manner. In this paper, we present the …


Reconnaissance Surveying Of Bechevin Bay, Ak Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Leland P. Snyder, Michael Gonsalves, John Nyberg Mar 2015

Reconnaissance Surveying Of Bechevin Bay, Ak Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Leland P. Snyder, Michael Gonsalves, John Nyberg

Center for Coastal and Ocean Mapping

Recently, a remote sensing study has been conducted over Bechevin Bay Channel, Alaska as part of a collaboration project between NOAA and the U.S. Coast Guard (USCG). The goal of the study to develop a procedure to prioritize survey areas and plan the annual deployment of Aids to Navigation (AtoN) along the channel. Bechevin Bay is considered a priority for marine surveying because it constitutes the easternmost passage through the Aleutians from the Bering Sea to the Gulf of Alaska. The channel is located in a mud flat area, where every winter the passage is closed due to ice cover. …