Time filter

Source Type

Lyndhurst, NJ, United States

Song F.,Rutgers University | Shin J.Y.,Meadowlands Environmental Research Institute | Jusino-Atresino R.,Rutgers University | Gao Y.,Rutgers University
Atmospheric Pollution Research

To characterize the relationships among the springtime NOx (NO + NO2), O3 and NO3 (defined as the combination of gaseous nitric acid, HNO3, and aerosol nitrate, NO3 -) concentrations in the ambient air of the vicinity of highways, an intensive sampling was carried out in spring 2007 at Lyndhurst, NJ in the U.S. East Coast. Ambient concentrations of O3 and NOx were measured by O3 and NOx analyzers, while NO3 was collected using a ChemComb cartridge and determined by ion chromatography. Significant variations in O3 concentrations were observed diurnally as well as between weekdays and weekends, with higher concentrations occurring during the daytime and on weekends. The 24-h diurnal variations of O3 and NOx could be divided into four periods: (1) morning NOx peak, (2) mid-day O3 formation, (3) afternoon NOx accumulation and (4) nighttime balancing. Daily averaged relative humidity and wind speed were the two weather parameters affecting O3 levels more than other averaged parameters, and daily maximum temperature was positively correlated to the maximum O3. Via photochemical reactions and emission- diffusion balance, NOx showed primarily negative influences on the daily O3 variations with decayed exponential correlations, in particular during nighttime and weekdays, indicating a possible VOC-sensitive characteristic of the study area. A negative correlation between NO3 - and O3 concentrations was found while no obvious influence of HNO3 on O3 was observed. Results by a multi-regression model involving three parameters (NO2/OX ratio, NO2 and HNO3) reveal that the NO2/OX ratio is an important parameter controlling the ground O3 level in the study area. © Author(s) 2011. Source

Artigas F.,Meadowlands Environmental Research Institute
ACM International Conference Proceeding Series

Information from the Census is tied to a State, County or Township boundaries and is dated to when the information was collected. Similarly, water quality, electricity consumption, and sociolinguistic accents are tied to geography and dated to when they were measured. Any attribute that is spatially explicit can be explored using Geographical Information Systems (GIS). GIS is a tool to find relationships and visualize trends and patterns between datasets that share the same geography. Researchers may be familiar with GIS's visually appealing results and its analytical powers and may even have ideas on how to apply this tool to their own research questions but have never had the chance to actually use this tool to generate tangible results on their own. These compressed hands on tutorial exercises on spatial analytics for open government data are designed to expose participants to levels of complexity that build on each other and explore an increasing range of functionalities offered by modern GIS. As a result, participants walk away having experienced the entire cycle of spatial analysis from identifying and importing data, performing overlays for spatial analysis and preparing map layouts and presentations to communicate the findings. Through this tutorial, participants should gain a basic understanding and practice of GIS to utilize this tool and address research problems in their own fields of expertise. Copyright © 2014 by the Association for Computing Machinery, Inc. Source

ElBishlawi H.,Princeton University | Shin J.Y.,Meadowlands Environmental Research Institute | Jaffe P.R.,Princeton University
Ecological Engineering

Two tidal marshes in the New Jersey Meadowlands, one constructed and one natural were characterized to compare their ability to immobilize trace metals (Cd, Cr, Cu, Mn, Pb, and Zn). Surface and pore waters were sampled four times a year between 2008 and 2010 and sediment cores were collected yearly in the constructed marsh and once in 2010 in the natural marsh. Interactions of trace metals with redox active species such as iron and sulfide as well as with organic matter were investigated. Precipitation with sulfides played a major role in immobilizing certain trace metals, including Cr, Mn, and Pb. At both sites, the presence of sulfide did not preclude the presence of dissolved trace metals in pore-water at concentrations exceeding their metal sulfide solubility product. Thermodynamic equilibrium modeling indicated these dissolved metals remained in solution due to an association with heterogeneous dissolved organic carbon. No net trace metal accumulation in the surficial sediments of the constructed marsh was noted between 2007 and 2010. This implied that a dynamic equilibrium of trace metal flux into and out of the sediments was established, rather than a long-term net accumulation of trace metals. In the constructed marsh, little difference was found between the immobilization potential in the area of intermittent flooding (high marsh) and the area of sustained flooding (low marsh). The newly constructed wetland immobilized significantly more Cr, Mn, and Zn than the natural marsh and similar concentrations of Cd, Cu, and Pb. This may be due to increased redox buffering through a larger FeS buffering pool against tidally induced oxygen delivery. © 2013 Elsevier B.V. Source

Schafer K.V.R.,Rutgers University | Tripathee R.,Rutgers University | Artigas F.,Meadowlands Environmental Research Institute | Morin T.H.,Ohio State University | Bohrer G.,Ohio State University
Journal of Geophysical Research G: Biogeosciences

Net ecosystem exchange (NEE) of tidal brackish wetlands in urban areas is largely unknown, albeit it is an important ecosystem service. High carbon dioxide (CO2) uptake of estuaries can potentially be achieved by creating conditions that foster CO2 uptake and sequestration. Thus, this study sought to assess NEE in a mesohaline tidal urban wetland that has been restored and determine the biophysical drivers of NEE in order to investigate uptake strength and drivers thereof. Beginning in 2009, NEE was measured using the eddy covariance technique in a restored urban estuarine wetland. Maximum NEE rates observed were -30 μmol m-2 s-1 under high light conditions in the summer. Monthly mean NEE showed this ecosystem to be a CO2 source in the winter, but a CO2 sink in summer. Conditional Granger causality showed the influence of net radiation on half daily to biweekly timescales on NEE and the influence of water level at half daily time scales. The overall productivity of this wetland is within the expected range of tidal brackish marshes and it was a sink for atmospheric CO2 in two out of the 3 years of this study and had a continued increase over the study period. ©2014. American Geophysical Union. All Rights Reserved. Source

Chun S.A.,CUNY - College of Staten Island | Artigas F.,Meadowlands Environmental Research Institute
ACM International Conference Proceeding Series

This study presents a Sensor Network based Tide Gate Monitoring System (SensorTGMS) that automatically collects the real-time water levels at tide gates in the New Jersey Meadowlands District where ninety percent of which lies within two feet of the high water mark. We report our experience of developing the SensorTGMS, and how the real-time water level data from the sensor-enabled tide gates provide water level alerts for government officials and citizens for planning evacuations and allocating resources by identifying risk areas in timely manner. The data, augmented with the social media data shared by citizens on their flood incident episodes can provide real-time situation awareness and promote community-based incident management during and after a disaster. Additionally, the SensorTGMS data supports the objective unbiased account of the progression of flood events. The animated visualization of the water levels over a time line can be a powerful tool for understanding where and how residents and infrastructure were affected by a high energy rain event and/or a tidal surge. This objective data captured by the system can be used as a forensic tool for understanding the weak points of coastal defenses and to assess the magnitude of the flood damages. Source

Discover hidden collaborations