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Estimated 2020 Co2 Emission Reductions In Virginia’S Transportation Sector From Covid-19, Eden E. Rakes, Pamela R. Grothe, Jeremy S. Hoffman Feb 2021

Estimated 2020 Co2 Emission Reductions In Virginia’S Transportation Sector From Covid-19, Eden E. Rakes, Pamela R. Grothe, Jeremy S. Hoffman

Virginia Journal of Science

The initial lockdown phase of the COVID-19 pandemic presented an unfortunate opportunity to observe how abrupt, large-scale changes in traffic volume can reduce greenhouse gas emissions. This study explores how carbon dioxide (CO2) emissions from Virginia’s transportation sector may have been affected by the changes in activity stemming from COVID-19 to inform more carbon-neutral policies as the state recovers from the economic downfall. Emission savings were calculated by multiplying the percent change from 2019 to 2020 in traffic volume from the Virginia Department of Transportation with the business-as-usual 2020 U.S. Environmental Protection Agency estimate of CO2 emissions …


Rates Of Relative Sea Level Rise Along The United States East Coast, Jesse N. Beckman, Joseph E. Garcia Apr 2019

Rates Of Relative Sea Level Rise Along The United States East Coast, Jesse N. Beckman, Joseph E. Garcia

Virginia Journal of Science

Recent studies have indicated that some coastal areas, including the East Coast of the United States, are experiencing higher rates of sea level rise than the global average. Rates of relative sea level rise are affected by changes in ocean dynamics, as well as by surface elevation fluctuations due to local land subsidence or uplift. In this study, we derived long-term trends in annual mean relative sea level using tide gauge data obtained from the Permanent Service for Mean Sea Level for stations along the United States East Coast. Stations were grouped by location into the Northeast, Mid-Atlantic, and Southeast …


Detecting Change: Observations Of Temperature And Precipitation Across Virginia’S Climate Divisions, Jeremy S. Hoffman, Michael J. Allen, Christopher F. Labosier Apr 2019

Detecting Change: Observations Of Temperature And Precipitation Across Virginia’S Climate Divisions, Jeremy S. Hoffman, Michael J. Allen, Christopher F. Labosier

Virginia Journal of Science

Modern global climate change is primarily attributable to human activities and the release of greenhouse gases into the atmosphere. Climate change impacts span a range of sectors, including agriculture, forestry, public health, and water resource management. The Commonwealth of Virginia has already and will continue to deal with many of these impacts, yet lacks concentrated effort to detect, document, and adapt to local climate changes. This study documents observed changes in temperature and precipitation across Virginia’s six climate divisions. Mean seasonal anomalies of minimum temperature, maximum temperature, and precipitation from 1986 to 2016 are examined relative to a long-term 1895-2000 …


Precipitation Trends Across The Commonwealth Of Virginia (1947 – 2016), Michael J. Allen, Thomas R. Allen Apr 2019

Precipitation Trends Across The Commonwealth Of Virginia (1947 – 2016), Michael J. Allen, Thomas R. Allen

Virginia Journal of Science

Water is an important resource for the Commonwealth of Virginia. Too much water increases runoff, disrupt transportation networks, and contributes to school closures. Too little water may adversely impact agricultural operations. To improve climate-related information to Virginia citizens, this study assesses means and changes in precipitation across the Commonwealth of Virginia (1947 – 2016). Using daily station-level precipitation data from the Global Historical Climate Network (GHCN), descriptive statistics were calculated for 43 locations in terms of total precipitation (inches decade-1), precipitation days (x>0”), and heavy precipitation days (x>1.0”). On average, locations showed an overall increase in …


Sea Level Rise In Virginia – Causes, Effects And Response, Tal Ezer, Larry P. Atkinson Oct 2015

Sea Level Rise In Virginia – Causes, Effects And Response, Tal Ezer, Larry P. Atkinson

Virginia Journal of Science

Sea level rise (SLR) along Virginia’s coasts and around the Chesapeake Bay as measured by tide gauges is analyzed and discussed. It is shown that the SLR rates vary between one location to another and in most locations the rates increase over time (i.e., SLR is accelerating). The latest science of SLR is reviewed and the causes of the high SLR rates in Virginia are discussed. The impacts of land subsidence and ocean currents (changes in the Gulf Stream in particular) on sea level are especially notable and important for predicting future SLR in Virginia. The consequences of SLR on …


Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall Apr 2014

Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall

Virginia Journal of Science

Phytoplankton composition from 16 Virginia lakes and reservoirs are discussed with emphasis on the dominant taxa, algal bloom producers, and potentially harmful species at these locations. This is a companion study to the more comprehensive publication regarding Virginia freshwater phytoplankton by Marshall (2013).


Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall Jan 2013

Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall

Virginia Journal of Science

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …


Late Holocene Sedimentation And Paleoenvironmental History For The Tidal Marshes Of The Potomac And Rappahannock Rivers, Tributaries To Chesapeake Bay, Neil E. Tibert, J. Bradford Hubeny, Mark Abbott, Joseph M. Kiker, Lindsay J. Walker, Shawn Mckenzie Oct 2012

Late Holocene Sedimentation And Paleoenvironmental History For The Tidal Marshes Of The Potomac And Rappahannock Rivers, Tributaries To Chesapeake Bay, Neil E. Tibert, J. Bradford Hubeny, Mark Abbott, Joseph M. Kiker, Lindsay J. Walker, Shawn Mckenzie

Virginia Journal of Science

Instrumental tide gauge records indicate that the modern rates of sea-level rise in the Chesapeake Bay more than double the global average of 1.2-1.5 mm yr-1. The primary objective for this study is to establish a relative depositional history for the tidal marshes of the Potomac and Rappahannock Rivers that will help us improve our understanding of processes that influence sedimentation in the proximal tributaries of Chesapeake Bay. Marsh cores were collected from Blandfield Point VA, Tappahannock VA, and Potomac Creek VA. The sedimentary facies include: 1) a lower unit of organic-poor, grey clay with fine sand and silt layers …


A Centennial Record Of Paleosalinity Change In The Tidal Reaches Of The Potomac And Rappahannock Rivers, Tributaries To Chesapeake Bay, Neil E. Tibert, Lindsay J. Walker, William P. Patterson, J. Bradford Hubeny, Emma Jones, Olivia R. Cooper Oct 2012

A Centennial Record Of Paleosalinity Change In The Tidal Reaches Of The Potomac And Rappahannock Rivers, Tributaries To Chesapeake Bay, Neil E. Tibert, Lindsay J. Walker, William P. Patterson, J. Bradford Hubeny, Emma Jones, Olivia R. Cooper

Virginia Journal of Science

Gravity and push cores from the Potomac and Rappahannock Rivers (Virginia Tidewater) were collected from central and proximal estuarine zones with known seasonal salinity stratification. The lowermost microfossil associations in the cores comprise alternating ostracode populations of Cyprideis salebrosa and Cytheromorpha. This microfossil association gives way to an oligohaline association dominated by the freshwater ostracode Darwinula stevensoni. Stable oxygen isotope values (δ18O) of Rapphannock Cyprideis salebrosa are highly variable ranging between -6.6 to -3.2‰ VPDB. δ18O values for Potomac Cytheromorpha fuscata range from -8.2 to -3.2‰ VPDB. Positive excursions in δ18O values …


Corrections To The Paper "Phytoplankton Productivity In The Tidal Regions Of Four Chesapeake Bay (Usa) Tributaries." Virginia Journal Of Science. 2007 58(4): 191-204, By K. K. Nesius, H. G. Marshall, And T.A. Egerton Apr 2010

Corrections To The Paper "Phytoplankton Productivity In The Tidal Regions Of Four Chesapeake Bay (Usa) Tributaries." Virginia Journal Of Science. 2007 58(4): 191-204, By K. K. Nesius, H. G. Marshall, And T.A. Egerton

Virginia Journal of Science

Necessary corrections associated with the paper "Phytoplankton productivity in the tidal regions of four Chesapeake Bay (USA) tributaries", originally published in Virginia Journal of Science Volume 58, Number 4, pages 191-204, in 2007, by K.K. Nesius, H.G. Marshall, and T.A. Egerton.


Phytoplankton Blooms: Their Occurrence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton Oct 2009

Phytoplankton Blooms: Their Occurrence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton

Virginia Journal of Science

Sporadic algal bloom development within a 10 year monitoring program in Virginia tidal tributaries of Chesapeake Bay is reviewed. These blooms were common events, characteristically producing a color signature to the surface water, typically short lived, occurring mainly from spring into autumn throughout different salinity regions of these rivers, and were produced primarily by dinoflagellates. The abundance threshold levels that would identify bloom status from a non-bloom presence were species specific, varied with the taxon's cell size, and ranged from ca. 10 to 104 cells mL-1. Among the most consistent sporadic bloom producers were the dinoflagellates Akashiwo …


First Records Of Hypleurochilus Geminatus And Centropristis Philadelphica From Chesapeake Bay, Aimee D. Halvorson Oct 2009

First Records Of Hypleurochilus Geminatus And Centropristis Philadelphica From Chesapeake Bay, Aimee D. Halvorson

Virginia Journal of Science

During the fall of 2007, Centropris philadelphica (rock seabass) and Hypleurochilus geminatus (Crested blenny) were collected from Chesapeake Bay. These captures are significant as they represent the first substantiated record of C. philadelphica from Chesapeake Bay and only the second and third validated records of H. geminatus. Additionally, the first record of H. geminatus from Chesapeake Bay was only recently recognized since the specimen had been previously misidentified as Parablennius marmoreus (seaweed blenny). The collection of seven individuals of H. geminatus in 2007, from two locations, indicates that the species may be resident within the Chesapeake Bay estuary.


High Resolution Dune Complex Mapping For The Monitoring Of Coastal Landform Change, First Landing State Park, Virginia, George M. Mcleod, Joe Daigneau, James Collins, Norma Swan, Thomas R. Allen Apr 2007

High Resolution Dune Complex Mapping For The Monitoring Of Coastal Landform Change, First Landing State Park, Virginia, George M. Mcleod, Joe Daigneau, James Collins, Norma Swan, Thomas R. Allen

Virginia Journal of Science

First Landing State Park is located on the southern shore of the mouth of the Chesapeake Bay. The park contains a prograding shoreline and dune complex that has been steadily growing northward. Accurate three dimensional mapping of the resident coastal dune features is challenging due to the dynamic nature of the dunescape. Precise mapping within First Landing was accomplished through careful planning, employ of advanced Global Positioning System (GPS) technology, and intensive data analysis. Mapping ensued during a period of optimal satellite signal availability and strength. Data points were collected at manual intervals with a Leica GS50+ GPS receiver, utilizing …


Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Harold G. Marshall, Lubomira Burchardt Jul 2005

Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Harold G. Marshall, Lubomira Burchardt

Virginia Journal of Science

Phytoplankton composition and the range of seasonal patterns of abundance are presented for the tidal freshwater regions in two Virginia rivers based on data accumulated monthly from 1986 through 1999. Diatoms dominated the flora during spring, summer, and fall, whereas, other taxonomic categories were more representative when the river flow rates decreased, allowing for a more stable water system and increased residency time within this tidal region during summer and early fall. This summer/fall period was associated with increased water temperatures, higher productivity rates and chlorophyll levels, increased total phytoplankton abundance and species diversity. The major components of the summer …


Correction [To Maurakis And Grimes Article, V. 54, #3&4] Oct 2004

Correction [To Maurakis And Grimes Article, V. 54, #3&4]

Virginia Journal of Science

This page is a correction to an article by Eugene G. Maurakis and David V. Grimes: Predicting Fish Species Diversity in Lotic Freshwaters of Greece, published in Virginia Journal of Science Volume 54, numbers 3 and 4. Amended table 2a owed to a printing corruption.


Chromium Tolerant Microbial Communities From The Chesapeake Bay Watershed, Kristine L. Lowe, Ruth E. Fliflet, Tony Ly, Brenda J. Little, Joanne Jones-Meehan Oct 2002

Chromium Tolerant Microbial Communities From The Chesapeake Bay Watershed, Kristine L. Lowe, Ruth E. Fliflet, Tony Ly, Brenda J. Little, Joanne Jones-Meehan

Virginia Journal of Science

Chromium tolerant bacteria were enumerated from portions of the Chesapeake Bay watershed and examined for their potential to reduce Cr(VI). Water and sediment samples were collected from various locations in Baltimore Harbor and Bear Creek, as well as Sandy Point State Park in Maryland and the Anacostia River in Washington, DC. Samples were spread onto agar plates with CrO42- (5 ppm) as the sole terminal electron acceptor. Plates were incubated anaerobically and colony forming units (CFU) enumerated. CFU arising on minimal-CrO42- medium ranged from 103-104 mL-1 or g-1 and community estimates …


Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware Apr 2001

Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware

Virginia Journal of Science

On December 23-25, 1998, a major ice storm struck southeastern Virginia. The storm-deposited glaze ice felled trees and limbs, causing a power outage and highway blockage. Between February and April, 1999, we recorded occurrence, severity, and type of damage to trees over 2.5 cm dbh in nine mostly gently sloping plots in Matoaka Woods at the College of William and Mary. Frequency and severity of damage varied with species and with size of trees. Canopy damage occurred in 75% of large Fagus grandifolia trees, but in only 6% of small Sassafras albidum stems. As a group, small (2.5 to 15 …


Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall Apr 2001

Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall

Virginia Journal of Science

Trachelomonas species from Lake Kilby, a reservoir lake in southeastern Virginia are described with supportive electron micrographs. The most abundant Trachelomonas species wereT. hispida and T. volvocina. Other members of the Euglenophyceae occurring in this lake are identified.