207 research outputs found
Establishing a Research Framework to Assess Permeable Pavement Sites at Ohio State
ENR 2367Ohio State has several permeable pavement sites, but university officials are not convinced that permeable pavement is right for campus. This project is a framework for student-led research that will assess permeable pavement's durability and impact on soil quality at Ohio State.Academic Major: Environment, Economy, Development, and SustainabilityAcademic Major: Environmental Scienc
Atmospheric oxidation chemistry and ozone production: Results from SHARP 2009 in Houston, Texas
This study considers whether spikes in nitrate in snow sampled at Summit, Greenland, from August 2000 to August 2002 are related to solar proton events. After identifying tropospheric sources of nitrate on the basis of correlations with sulfate, ammonium, sodium, and calcium, we use the three-dimensional global Whole Atmosphere Community Climate Model (WACCM) to examine unaccounted for nitrate spikes. Model calculations confirm that solar proton events significantly impact HOx, NOx, and O3 levels in the mesosphere and stratosphere during the weeks and months following the major 9 November 2000 solar proton event. However, solar proton event (SPE)-enhanced NOy calculated within the atmospheric column is too small to account for the observed nitrate peaks in surface snow. Instead, our WACCM results suggest that nitrate spikes not readily accounted for by measurement correlations are likely of anthropogenic origin. These results, consistent with other recent studies, imply that nitrate spikes in ice cores are not suitable proxies for individual SPEs and motivate the need to identify alternative proxies
Nitrate deposition to surface snow at Summit, Greenland, following the 9 November 2000 solar proton event
Abstract This study considers whether spikes in nitrate in snow sampled at Summit, Greenland, from August 2000 to August 2002 are related to solar proton events. After identifying tropospheric sources of nitrate on the basis of correlations with sulfate, ammonium, sodium, and calcium, we use the three-dimensional global Whole Atmosphere Community Climate Model (WACCM) to examine unaccounted for nitrate spikes. Model calculations confirm that solar proton events significantly impact HOx, NOx, and O3 levels in the mesosphere and stratosphere during the weeks and months following the major 9 November 2000 solar proton event. However, solar proton event (SPE)-enhanced NOy calculated within the atmospheric column is too small to account for the observed nitrate peaks in surface snow. Instead, our WACCM results suggest that nitrate spikes not readily accounted for by measurement correlations are likely of anthropogenic origin. These results, consistent with other recent studies, imply that nitrate spikes in ice cores are not suitable proxies for individual SPEs and motivate the need to identify alternative proxies. Key Points A global model simulates nitrate deposition from solar proton events Soluble ion correlations in Summit snow identify tropospheric sources of nitrate Nitrate ions in snow are found not to be a good proxy for solar proton events
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Tell el-Amarna Site Management Plan 2020
The archaeological landscape of Egypt is rich in tombs and temples but offers little in the way of intelligible and easily accessible places where ancient Egyptians actually lived. In Tell el-Amarna (Amarna for short) we have the greater part of a major city: its public buildings, its housing neighbourhoods, the decorated tombs of its governing class and the cemeteries of the ordinary people. Having been occupied for only about twenty years it preserves unique evidence for how people lived in the past. As the creation of Pharaoh Akhenaten, it also serves as a powerful introduction to the individual and his ideas.
Archaeologists have worked at Amarna for over a century. But the place needs more than their expert attentions. Like many sites around the world, Amarna is threatened by the effects of rapid modernisation and population growth. The Site Management Plan presented here seeks to anchor Amarna more firmly to the current development policies of the Egyptian government. These emphasise the importance of cooperation amongst the varied sectors of Egyptian society, both those of the government and those constituted by local communities. The Plan seeks to guide the decision-making of the future in the hope of securing Amarna as an educational resource for generations to come.
The Plan itself has been an exercise in co-operation. We wish to thank all those who have assisted. They comprise the many officials of the Ministry of Tourism and Antiquities, in Cairo and in the inspectorates of El-Minya Province, local community leaders at Amarna and, not least, representatives of the local inhabitants including those of school age
Teleporters, tunnels & time : Understanding warp devices in videogames
Catchment land uses, particularly agriculture and urban uses, have long been recognized as major drivers of nutrient concentrations in surface waters. However, few simple models have been developed that relate the amount of catchment land use to downstream freshwater nutrients. Nor are existing models applicable to large numbers of freshwaters across broad spatial extents such as regions or continents. This research aims to increase model performance by exploring three factors that affect the relationship between land use and downstream nutrients in freshwater: the spatial extent for measuring land use, hydrologic connectivity, and the regional differences in both the amount of nutrients and effects of land use on them. We quantified the effects of these three factors that relate land use to lake total phosphorus (TP) and total nitrogen (TN) in 346 north temperate lakes in 7 regions in Michigan, USA. We used a linear mixed modeling framework to examine the importance of spatial extent, lake hydrologic class, and region on models with individual lake nutrients as the response variable, and individual land use types as the predictor variables. Our modeling approach was chosen to avoid problems of multi-collinearity among predictor variables and a lack of independence of lakes within regions, both of which are common problems in broad-scale analyses of freshwaters. We found that all three factors influence land use-lake nutrient relationships. The strongest evidence was for the effect of lake hydrologic connectivity, followed by region, and finally, the spatial extent of land use measurements. Incorporating these three factors into relatively simple models of land use effects on lake nutrients should help to improve predictions and understanding of land use-lake nutrient interactions at broad scales
Design for ground beetle abundance and diversity sampling within the National Ecological Observatory Network
The National Ecological Observatory Network (NEON) will monitor ground beetle populations across a network of broadly distributed sites because beetles are prevalent in food webs, are sensitive to abiotic factors, and have an established role as indicator species of habitat and climatic shifts. We describe the design of ground beetle population sampling in the context of NEON's long-term, continentalscale monitoring program, emphasizing the sampling design, priorities, and collection methods. Freely available NEON ground beetle data and associated field and laboratory samples will increase scientific understanding of how biological communities are responding to land-use and climate change.Peer reviewe
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