Physical Sciences and Mathematics Commons^™

Recent Disruptions In The Timing And Intensity Of Precipitation In Calakmul, Mexico, Sofia Mardero, Birgit Schmook, Zachary Christman, Sarah E. Metcalfe, Betsabé De La Barreda-Bautista

School of Earth & Environment Faculty Scholarship

This study addresses changes in the timing and intensity of precipitation from 1982 to 2016 from three meteorological stations around Calakmul, Mexico, a landscape balancing biodiversity conservation and smallholder agricultural production. Five methods were used to assess changes in precipitation: the Mann-Kendall test of annual and wet season trends; a fuzzy-logic approach to determine the onset of the rainy season; the Gini Index and Precipitation Concentration Index (PCI) to evaluate the temporal distribution of precipitation; Simple Precipitation Intensity Index (SDII) to evaluate precipitation intensity; and the Rainfall Anomaly Index (RAI) to identify the deficit or surplus of rainfall compared with …

An Analysis Of The Atmospheric Propagation Of Underground-Explosion-Generated Infrasonic Waves Based On The Equations Of Fluid Dynamics: Ground Recordings, Roberto Sabatini, Jonathan B. Snively, Michael P. Hickey, J. L. Garrison

Publications

An investigation on the propagation of underground-explosion-generated infrasonic waves is carried out via numerical simulations of the equations of fluid dynamics. More specifically, the continuity, momentum, and energy conservation equations are solved along with the Herzfeld-Rice equations in order to take into account the effects of vibrational relaxation phenomena. The radiation of acoustic energy by the ground motion caused by underground explosions is initiated by enforcing the equality, at ground level, between the component of the air velocity normal to the Earth's surface and the normal velocity of the ground layer. The velocity of the ground layer is defined semi-empirically …

Estimating Carbon Flux From Optically Recording Total Particle Volume At Depths Below The Primary Pycnocline, Alexander B. Bochdansky, Robert B. Dunbar, Dennis A. Hansell, Gerhard J. Herndl

OES Faculty Publications

Optical instruments can rapidly determine numbers and characteristics of water column particles with high sensitivity. Here we show the usefulness of optically assessed total particle volume below the main pycnocline to estimate carbon export in two systems: the open subarctic North Atlantic and the Ross Sea, Antarctica. Both regions exhibit seasonally high phytoplankton production and efficient export (i.e., a strong biological pump). Total particle volumes in the mesopelagic (200-300 m) were significantly correlated with those in the overlying surface mixed layer (50-60 m), indicating that most particles at depth reflect export from the surface. This connectivity, however, is modulated by …

Diel Temperature And Ph Variability Scale With Depth Across Diverse Coral Reef Habitats, Tyler Cyronak, Yuichiro Takeshita, Travis A. Courtney, Eric H. Decarlo, Bradley D. Eyre, David I. Kline, Todd R. Martz, Heather Page, Nichole Price, Jennifer Smith, Laura Stoltenberg, Martin Tresguerres, Andreas J. Andersson

Marine & Environmental Sciences Faculty Articles

Coral reefs are facing intensifying stressors, largely due to global increases in seawater temperature and decreases in pH. However, there is extensive environmental variability within coral reef ecosystems, which can impact how organisms respond to global trends. We deployed spatial arrays of autonomous sensors across distinct shallow coral reef habitats to determine patterns of spatiotemporal variability in seawater physicochemical parameters. Temperature and pH were positively correlated over the course of a day due to solar heating and light‐driven metabolism. The mean temporal and spatial ranges of temperature and pH were positively correlated across all sites, with different regimes of variability …

Optimization Of Over-Summer Snow Storage At Midlatitudes And Low Elevation, Hannah S. Weiss, Paul R. Bierman, Yves Dubief, Scott D. Hamshaw

College of Arts and Sciences Faculty Publications

Climate change, including warmer winter temperatures, a shortened snowfall season, and more rain-on-snow events, threatens nordic skiing as a sport. In response, oversummer snow storage, attempted primarily using woodchips as a cover material, has been successfully employed as a climate change adaptation strategy by high-elevation and/or high-latitude ski centers in Europe and Canada. Such storage has never been attempted at a site that is both low elevation and midlatitude, and few studies have quantified storage losses repeatedly through the summer. Such data, along with tests of different cover strategies, are prerequisites to optimizing snow storage strategies. Here, we assess the …

Sixteen Years Of Social And Ecological Dynamics Reveal Challenges And Opportunities For Adaptive Management In Sustaining The Commons, Josh Eli Cinner, J. D. Lau, Andrew G. Bauman, David A. Feary, Fraser A. Januchowski-Hartley, C. A. Rojas, M. L. Barnes, B. J. Bergseth, E. Shum, R. Lahari, J. Ben, N. A. J. Graham

Marine & Environmental Sciences Faculty Articles

Efforts to confront the challenges of environmental change and uncertainty include attempts to adaptively manage social–ecological systems. However, critical questions remain about whether adaptive management can lead to sustainable outcomes for both ecosystems and society. Here, we make a contribution to these efforts by presenting a 16-y analysis of ecological outcomes and perceived livelihood impacts from adaptive coral reef management in Papua New Guinea. The adaptive management system we studied was a customary rotational fisheries closure system (akin to fallow agriculture), which helped to increase the biomass of reef fish and make fish less wary (more catchable) relative to openly …

Beavers Alter Stream Macroinvertebrate Communities In Northeastern Utah, Susan E. Washko, Brett B. Roper, Trisha Brooke Atwood

Watershed Sciences Faculty Publications

1. Understanding changes in macroinvertebrate communities is important because they play a large role in stream ecosystem functioning, and they are an important food resource for fish. Beaver‐induced changes to stream morphology could alter macroinvertebrate communities, which in turn could affect food webs and ecosystem function. However, studies investigating the effects of North American beaver activities on macroinvertebrates are rare in the inter‐mountain west, an area with high potential for beaver‐assisted restoration.
2. The aim of this study was to quantify differences in the macroinvertebrate community between unaltered segments of streams and within beaver ponds in north‐eastern Utah, U.S.A. We assessed macroinvertebrate …

Vintage Report 2019: North Willamette Valley, Gregory V. Jones

Linfield University Wine Studies Reports

This report describes the impacts of climate and phenology on vintage for the North Willamette Valley in Oregon in 2019. A relatively mild early winter in 2018 was followed by a cold and wet second half of winter in 2019 and then a wet, but warm, spring. The growing season saw a few mild frosts during late April, but started off warmer than average, moderating through mid-vintage with fewer than average heat spikes. Near-record precipitation amounts during late June and early July brought increased disease pressure to the region. The vintage will be remembered for the early rains in September …

A Climatology Of Snowpack In The Southern Rocky Mountains And Snow To Liquid Ratio Forecasting Techniques Using Model Generated Soundings From The Rapid Refresh Model, Carson Jones

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Mountainous snowpack represents up to 70% of the total water resources for areas in the western United States. Temperature and precipitation control the accumulation and ablation of the snowpack throughout the cold season, both of which are subject to a changing climate. This study will use a network of snow telemetry (SNOTEL) stations to investigate changes in the snowpack season, snow water equivalent (SWE), and temperature in the southern Rocky Mountain region. Additionally, this study will use model generated soundings from the Rapid Refresh (RAP) model to establish relationships between the depth and cloud proportion of ice crystal growth layers, …

Steve And The Picket Fence: Evidence Of Feedback-Unstable Magnetosphere-Ionosphere Interaction, Evgeny Mishin, Anatoly Streltsov

Publications

This paper aims to extend the understanding of Strong Thermal Emission VelocityEnhancement (STEVE) and the Picket Fence related to strong subauroral ion drifts (SAID). Wenumerically demonstrated that precipitating energetic electrons are critical for the structuring of the PicketFence. It is created by feedback-unstable magnetosphere-ionosphere interactions driven by the SAIDelectric field when the Hall conductance created by energetic (≥1 keV) electrons exceeds the Pedersenconductance. We show that thermal excitation of the red-line emission in STEVE is inhibited by inelasticcollisions with molecular nitrogen. Suprathermal (≤500 eV) electrons coming from the turbulentplasmasphere appear to be the major source. We also show that the …

Life In Hampton Roads Survey No. 4: Neighborhood Flooding And Insurance, News @ Odu

News Items

No abstract provided.

Weather And Climate Summary And Forecast: December 2019 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for December 2019. It includes forecast information specific to the Pacific Northwest and the western United States, as well as forecast information for other portions of the United States and abroad.

Multilayer Observations And Modeling Of Thunderstorm-Generated Gravity Waves Over The Midwestern United States, C. J. Heale, J. B. Snively, A. N. Bhatt, L. Hoffmann, C. C. Stephan

Publications

We present multilayer observations and numerical simulations of gravity waves (GWs) generated by a series of Mesoscale Convective Systems over the midwestern United States. Strong semiconcentric GWs were observed and modeled, which couple from their tropospheric sources to the thermosphere, displaying strong nonlinearity indicated by instability, breaking, and formation of turbulent vortices. GWs in the stratosphere display a large range of horizontal scales from 34–400 km; however, the smaller wavelength waves break rapidly in the mesosphere and lower thermosphere. Larger-scale (≥150 km) waves dominate in the thermosphere and display northwestward propagation at 200–300 km altitude, opposing the mean winds. Despite …

Importance Of Refractory Ligands And Their Photodegradation For Iron Oceanic Inventories And Cycling, Christel Hassler, Damien Cabanes, Sonia Blanco-Ameijeiras, Sylvia G. Sander, Ronald Benner

Faculty Publications

Iron is an essential micronutrient that limits primary production in up to 40% of the surface ocean and influences carbon dioxide uptake and climate change. Dissolved iron is mostly associated with loosely characterised organic molecules, called ligands, which define key aspects of the iron cycle such as its residence time, distribution and bioavailability to plankton. Models based on in situ ligand distributions and the behaviour of purified compounds include long-lived ligands in the deep ocean, bioreactive ligands in the surface ocean and photochemical processes as important components of the iron cycle. Herein, we further characterise biologically refractory ligands in dissolved …

Examining The Effects Of Greenland Ice Sheet Melting And Atlantic Meridional Shutdown On The Climate Of Scandinavia And The British Isles, Tyler Lemburg

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Earth’s climate has been rapidly changing over the last hundred years, and its global average temperature is rising. However, climate change is far more complicated than a simple increase in temperature. For example, it is theorized that certain regions of Earth, including Scandinavia and the British Isles, could actually become cooler through ongoing climate change processes. Two of these processes are Greenland Ice Sheet (GrIS) melting, and slowdown of the Atlantic Meridional Overturning Circulation (AMOC). This research examines if climate change, through GrIS melting and AMOC slowdown, could contribute to cooler, instead of warmer, temperatures in Scandinavia and the British …

The Northwestern Greenland Ice Sheet During The Early Pleistocene Was Similar To Today, Andrew J. Christ, Paul R. Bierman, Paul C. Knutz, Lee B. Corbett, Julie C. Fosdick, Elizabeth K. Thomas, Owen C. Cowling, Alan J. Hidy, Marc W. Caffee

College of Arts and Sciences Faculty Publications

The multi-million year history of the Greenland Ice Sheet remains poorly known. Ice-proximal glacial marine diamict provides a direct but discontinuous record of ice sheet behavior; it is underutilized as a climate archive. Here, we present a novel multiproxy analysis of an Early Pleistocene marine diamict from northwestern Greenland. Low cosmogenic nuclide concentrations indicate minimal near-surface exposure, similar to modern terrestrial sediment. Detrital apatite (U-Th-Sm)/He (AHe) ages all predate glaciation by >150 million years, suggesting the northwestern Greenland Ice Sheet had, by 1.9 Ma, not yet incised fjords of sufficient depth to excavate grains with young AHe ages. The diamict …

Water Quality Improvements Offset The Climatic Debt For Stream Macroinvertebrates Over Twenty Years, Ian P. Vaughan, Nicholas J. Gotelli

College of Arts and Sciences Faculty Publications

Many species are accumulating climatic debt as they fail to keep pace with increasing global temperatures. In theory, concomitant decreases in other stressors (e.g. pollution, fragmentation) could offset some warming effects, paying climatic debt with accrued environmental credit. This process may be occurring in many western European rivers. We fit a Markov chain model to ~20,000 macroinvertebrate samples from England and Wales, and demonstrate that despite large temperature increases 1991–2011, macroinvertebrate communities remained close to their predicted equilibrium with environmental conditions. Using a novel analysis of multiple stressors, an accumulated climatic debt of 0.64 (±0.13 standard error) °C of warming …

Sustainablewell-Being Challenge: A Student-Centered Pedagogical Tool Linking Human Well-Being To Ecological Flourishing, Christine Vatovec, Haley Ferrer

Rubenstein School of Environment and Natural Resources Faculty Publications

Human behavioral change is necessary if we wish to evolve into a more sustainable human society, but change is hard, especially given that many people equate environmentalism with personal sacrifice. This paper highlights a semester-long assignment in which undergraduate students examined five behaviors that claim to increase happiness with minimal ecological footprints. We used mixed methods to analyze students' self-reported positive and negative affect scores before and after completing each of the five activities, along with descriptions of the carbon footprint of each activity and student self-reflections on whether each challenge promoted "sustainability". Results indicated that students' positive affect increased …

Vegetation Classification And Mapping, Missouri National Recreational River, Tom Baldvins, Matt Ley, David Jones, Joe Stevens, Hannah Pilkington

United States National Park Service: Publications

Executive Summary

The vegetation inventory project at Missouri National Recreational River (MNRR) classified and mapped vegetation within the park administrative boundary and estimated thematic map accuracy quantitatively. The project was conducted over a four year period from the summer of 2015 to the winter of 2019.

The project follows guidance provided by the National Park Service (NPS) Vegetation Mapping Inventory (VMI) Program. The overall process includes initial planning and scoping, imagery procurement, field data collection, data analysis, imagery interpretation and classification, and accuracy assessment. The initial planning and scoping meetings to support study plan development took place in December, 2009, …

E700xd Portable Doppler Radar Energy Systems Analysis, Brandon M. Bailey [*], Torrey J. Wagner, Jada Williams

Faculty Publications

Occurring in industrialized nations, inexpensive and abundantly available power is routinely taken for granted. However, energy resilience and to a lesser extent price are key concerns when considering potential solutions for disaster response, disaster relief, or military operations. The Department of Defense (DoD) currently uses a 5 kW generator to power the E700XD portable Doppler radar system when grid power is unavailable [1]. While the radar has an approximate power consumption of 2.5 kW, there is a potential for higher demand due to weather conditions [2]. This paper examines the cost of operating a currently installed generator, compared to the …

Evidence Of Limited Recruitment Of Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen, Kimberly Chojnacki, Jeffrey A. Kalie, Meredith L. Bartron, Edward J. Heist, Kyle R. Winders, Nathan C. Loecker, Wyatt J. Doyle, Timothy L. Welker

United States Geological Survey: Staff Publications

Pallid Sturgeon Scaphirhynchus albus are endemic to the Missouri and Mississippi river basins and are rare throughout their range. The species was listed as federally endangered with little to no evidence of natural recruitment. Since population augmentation was initiated as a recovery objective in the early 1990s, thousands of hatchery-origin Pallid Sturgeon have been stocked in the lower Missouri River (Gavins Point Dam [river kilometer 1,305.1] to the confluence of the Mississippi River [river kilometer 0.0]). Efforts to discriminate natural reproduction and recruitment of wild-origin Pallid Sturgeon from hatchery-origin fish has been hampered by tag loss in hatchery-origin sturgeon, inconsistent …

Increased Fluvial Runoff Terminated Inorganic Aragonite Precipitation On The Northwest Shelf Of Australia During The Early Holocene, Maximilian Hallenberger, Lars Reuning, Stephen J. Gallagher, Stefan Back, Takeshige Ishiwa, Beth A. Christensen, Kara Bogus

School of Earth & Environment Faculty Scholarship

Inorganic precipitation of aragonite is a common process within tropical carbonate environments. Across the Northwest Shelf of Australia (NWS) such precipitates were abundant in the late Pleistocene, whereas present-day sedimentation is dominated by calcitic bioclasts. This study presents sedimentological and geochemical analyses of core data retrieved from the upper 13 meters of IODP Site U1461 that provide a high-resolution sedimentary record of the last ~15 thousand years. Sediments that formed from 15 to 10.1 ka BP are aragonitic and characterised by small needles (<5 >µm) and ooids. XRF elemental proxy data indicate that these sediments developed under arid conditions in …

Defining Boat Wake Impacts On Shoreline Stability Toward Management And Policy Solutions, Donna Marie Bilkovic, Molly M. Mitchell, Jennifer Davis, Julie Herman, Elizabeth Andrews, Angela King, Pamela Mason, Navid Tahvildari, Jana Davis, Rachel L. Dixon

Civil & Environmental Engineering Faculty Publications

Coastal economies are often supported by activities that rely on commercial or recreational vessels to move people or goods, such as shipping, transportation, cruising, and fishing. Unintentionally, frequent or intense vessel traffic can contribute to erosion of coastlines; this can be particularly evident in sheltered systems where shoreline erosion should be minimal in the absence of boat waves. We reviewed the state of the science of known effects of boat waves on shoreline stability, examined data on erosion, turbidity, and shoreline armoring patterns for evidence of a response to boat waves in Chesapeake Bay, and reviewed existing management and policy …

Growth Phase Proteomics Of The Heterotrophic Marine Bacterium Ruegeria Pomeroyi, Dasha Krayushkina, Emma Timmins-Schiffman, Jessica Faux, Damon H. May, Michael Riffle, H. Rodger Harvey, Brook L. Nunn

OES Faculty Publications

The heterotrophic marine bacterium, Ruegeria pomeroyi, was experimentally cultured under environmentally realistic carbon conditions and with a tracer-level addition of ¹³C-labeled leucine to track bacterial protein biosynthesis through growth phases. A combination of methods allowed observation of real-time bacterial protein production to understand metabolic priorities through the different growth phases. Over 2000 proteins were identified in each experimental culture from exponential and stationary growth phases. Within two hours of the ¹³C-labeled leucine addition, R. pomeroyi significantly assimilated the newly encountered substrate into new proteins. This dataset provides a fundamental baseline for understanding growth phase differences in molecular …

Temporal And Spatial Scales Of Correlation In Marine Phytoplankton Communities, A. M. Kuhn, S. Dutkiewicz, O. Jahn, Sophie Clayton, T. A. Rynearson, M. R. Mazloff, A. D. Barton

OES Faculty Publications

Ocean circulation shapes marine phytoplankton communities by setting environmental conditions and dispersing organisms. In addition, processes acting on the water column (e.g., heat fluxes and mixing) affect the community structure by modulating environmental variables that determine in situ growth and loss rates. Understanding the scales over which phytoplankton communities vary in time and space is key to elucidate the relative contributions of local processes and ocean circulation on phytoplankton distributions. Using a global ocean ecosystem model, we quantify temporal and spatial correlation scales for phytoplankton phenotypes with diverse functional traits and cell sizes. Through this analysis, we address these questions: …

Dynamic Accretion Beneath A Slow-Spreading Ridge Segment: Iodp Hole 1473a And The Atlantis Bank Oceanic Core Complex, Henry J.B. Dick, Christopher J. Macleod, Peter Blum, Natsue Abe, Donna K. Blackman, Julie A. Bowles, M.J. Cheadle, K. Cho, Jakub Ciazela, Jeremy Deans, Virginia P. Edgcomb, C. Ferrando, Lyderic France, B. Ghosh, Benoit Ildefonse, Barbara John, Mark A. Kendrick, J. Koepke, James A.M. Leong, C. Liu, Q. Ma, T. Morishita, A. Morris, J.H. Natland, T. Nozaka, O. Pluemper, A. Sanflippo, J.B. Sylvan, Maurice A. Tivey, R. Tribuzio, G. Viegas

Faculty Publications

809 deep IODP Hole U1473A at Atlantis Bank, SWIR, is 2.2 km from 1,508‐m Hole 735B and 1.4 from 158‐m Hole 1105A. With mapping, it provides the first 3‐D view of the upper levels of a 660‐km² lower crustal batholith. It is laterally and vertically zoned, representing a complex interplay of cyclic intrusion, and ongoing deformation, with kilometer‐scale upward and lateral migration of interstial melt. Transform wall dives over the gabbro‐peridotite contact found only evolved gabbro intruded directly into the mantle near the transform. There was no high‐level melt lens, rather the gabbros crystallized at depth, and then emplaced …

Umphlett Qci Dec 2019, Natalie A. Umphlett

High Plains Regional Climate Center: Personnel Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Soil Moisture Conditions

Agriculture

Energy

Infrastructure

Temperature

Precipitation

A Case Study Of Stratospheric Ozone Transport To The Northern San Francisco Bay Area And Sacramento Valley During Cabots 2016, Jodie Clark, Sen Chiao

Faculty Research, Scholarly, and Creative Activity

The California Baseline Ozone Transport Study (CABOTS) was a major air quality study that collected ozone measurements aloft between mid-May and mid-August of 2016. Aircraft measurements, ground-based lidar measurements, and balloon-borne ozonesondes collected precise upper-air ozone measurements across the central and Southern California valley. Utilizing daily ozonesonde data from Bodega Bay, California, and Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), reanalysis data for 25 July to 14 August 2016, three stratospheric intrusion events are identified over Northern California influencing air masses above Bodega Bay and Sacramento simultaneously. Calculated percent daily changes in afternoon ozonesonde observations indicate increasing …

Long-Term Aerosol Trends And Variability Over Central Saudi Arabia Using Optical Characteristics From Solar Village Aeronet Measurements, Mohammed Al Otaibi, Ashraf Farahat, Bassam Tawabini, M. Hafidz Omar, Emad Ramadan, Abdelgadir Abuelgasim, Ramesh Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Natural and anthropogenic aerosols over the Kingdom of Saudi Arabia (KSA) play a major role in affecting the regional radiation budget. The long-term variability of these aerosols’ physical and optical parameters, including aerosol optical depth (AOD) and Ångström exponent (α), were measured at a location near central KSA using the Solar Village (SV) AERONET (Aerosol Robotic Network) station during the period December 1999–January 2013. The AERONET measurements show an overall increase in AOD on an annual basis. This upward trend is mainly attributed to a prolonged increase in the monthly/seasonal mean AOD during March–June and during August– September. In contrast, …

Water Vapor Near-Uv Absorption: Laboratory Spectrum, Field Evidence, And Atmospheric Impacts, Linsen Pei, Qilong Min, Yuyi Du, Zhechen Wang, Bangsheng Yin, Kai Yang, Patrick Disterhoft, Thomas Pongetti, Lei Zhu

Environmental Health Sciences Faculty Scholarship

Absorption of solar radiation by water vapor in the near-UV region is a poorly-understood but important issue in atmospheric science. To better understand water vapor near-UV absorption, we constructed a cavity ring-down spectrometer with bandwidth of 5 cm^-1 (~0.05 nm) and obtained water vapor absorption cross-sections at 1 nm increments in the 290-350 nm region. Water vapor displays structured absorption over this range with maximum and minimum cross-sections of 8.4×10^-25 and 1.6×10^-25 cm²/molecule. Major water vapor absorption bands were observed at 293-295, 307-313, 319, 321-322, and 325 nm, with cross-section values higher than 4.0×10^{-25 …}