Attribution of Trends and Variability in Surface Ozone over the United States

Concentrations of tropospheric ozone, a greenhouse gas and air pollutant, are impacted by changes in precursor emissions as well meteorology and influx from the stratosphere. Observations show a decreasing trend in summertime surface ozone at rural stations in the eastern United States, while some western stations show increasing trends, particularly in springtime. We use the Global Modeling Initiative (GMI) global chemical transport model to investigate the roles of precursor emission changes, meteorological variability, and stratosphere-troposphere exchange (STE) in explaining observed trends in surface ozone from rural sites in the United States from 1991-2010. The model's interannual variability shows significant correlations with observations from many of the surface sites. We also compare the simulated ozone to ozonesonde data for several locations with sufficiently long records. We compare a simulation with time-dependent precursor emissions, including emission reductions over the United States and Europe and increases over Asia, to a simulation with fixed emissions to quantify the impact of changing emissions on the surface trends. The simulation with varying emissions reproduces much of the east-west difference in summertime ozone over the U.S., although it generally underestimates the negative trend in the East. In contrast, the fixed-emission simulation shows increasing ozone at both eastern and western sites. We will discuss possible causes of this behavior, including long-range transport and STE

The astrobiology primer: An outline of general knowledge - Version 1, 2006

Peer reviewe

Video Editing and Manipulation: Stuckey Grills Ocasio-Cortez

This tutorial studies video manipulation through the case study of an edited interview video featuring an elected official. You can contact a librarian to request customized content for your classes. A librarian will respond to refine the content and format of your requested materials within one to two business days

The Ozone Budget in the Upper Troposphere from Global Modeling Initiative (GMI)Simulations

Ozone concentrations in the upper troposphere are influenced by in-situ production, long-range tropospheric transport, and influx of stratospheric ozone, as well as by photochemical removal. Since ozone is an important greenhouse gas in this region, it is particularly important to understand how it will respond to changes in anthropogenic emissions and changes in stratospheric ozone fluxes.. This response will be determined by the relative balance of the different production, loss and transport processes. Ozone concentrations calculated by models will differ depending on the adopted meteorological fields, their chemical scheme, anthropogenic emissions, and treatment of the stratospheric influx. We performed simulations using the chemical-transport model from the Global Modeling Initiative (GMI) with meteorological fields from (It)h e NASA Goddard Institute for Space Studies (GISS) general circulation model (GCM), (2) the atmospheric GCM from NASA's Global Modeling and Assimilation Office(GMAO), and (3) assimilated winds from GMAO . These simulations adopt the same chemical mechanism and emissions, and adopt the Synthetic Ozone (SYNOZ) approach for treating the influx of stratospheric ozone -. In addition, we also performed simulations for a coupled troposphere-stratosphere model with a subset of the same winds. Simulations were done for both 4degx5deg and 2degx2.5deg resolution. Model results are being tested through comparison with a suite of atmospheric observations. In this presentation, we diagnose the ozone budget in the upper troposphere utilizing the suite of GMI simulations, to address the sensitivity of this budget to: a) the different meteorological fields used; b) the adoption of the SYNOZ boundary condition versus inclusion of a full stratosphere; c) model horizontal resolution. Model results are compared to observations to determine biases in particular simulations; by examining these comparisons in conjunction with the derived budgets, we may pinpoint deficiencies in the representation of chemical/dynamical processes

Food Access, Identity, and Taste in Two Rural Cuban Communities

While many scholars have examined the idea of consumption preferences, also known as taste, in capitalist contexts, they have not explored how taste manifests in socialist or communist societies. In this case study, we query the ways in which two Cuban communities express taste through food choices and consumption patterns. We find that identity influences preferences less than the prevailing discourse around Cuban cuisine suggests. In addition, patterns among subjects’ responses speak to the ways in which local custom and larger structural forces intersect in respondents\u27 lives. Instead of simply reflecting the notion of class differentiation through consumption, our subjects reveal the significance of gender roles and individual relationships to food production in their discussions of preferences. Thus, this study demonstrates that, while food preferences appear in this resource-constrained context, taste and actuality do not always align

La Picadora: A Case Study in Cuban Agroecotourism

Agroecotourism is growing worldwide, with a Latin American focus on both cultural and environmental sustainability. In this case study, the authors immersed themselves in the seven-year-old agroecotourism venture of La picadora, living among neighbours and conducting formal interviews with 14 persons to learn about agricultural practices, hosting approaches, and the effects of tourism on life at La picadora. Results showed a community practising and committed to sustainable use of land and human resources, and revealed agricultural practices typical of broader Cuba. Foods served to tourists reflected a combination of Cuban tradition and ingredient availability. Residents noted cultural and monetary benefits of welcoming tourists to their communities. In conclusion, the La picadora collective is a microcosm of sustainable tourism, affecting and affected by broader socioeconomic forces. It is likely that this early agroecotourism adopter will become a model for other Cuban visitor hubs operating outside traditional beach-based ventures

La Picadora: A Case Study in Cuban Agroecotourism

Agroecotourism is growing worldwide, with a Latin American focus on both cultural and environmental sustainability. In this case study, the authors immersed themselves in the seven-year-old agroecotourism venture of La picadora, living among neighbours and conducting formal interviews with 14 persons to learn about agricultural practices, hosting approaches, and the effects of tourism on life at La picadora. Results showed a community practising and committed to sustainable use of land and human resources, and revealed agricultural practices typical of broader Cuba. Foods served to tourists reflected a combination of Cuban tradition and ingredient availability. Residents noted cultural and monetary benefits of welcoming tourists to their communities. In conclusion, the La picadora collective is a microcosm of sustainable tourism, affecting and affected by broader socioeconomic forces. It is likely that this early agroecotourism adopter will become a model for other Cuban visitor hubs operating outside traditional beach-based ventures

Beyond Fake News: Identifying Problems within Evolving Information Technologies Online

This tutorial collection will help you gain an understanding of the complexity of fake news. Each module will help you understand problems related to fake news and other types of misinformation. Tutorials are grouped into three categories: The Basics of Misinformation, Problematic Sources, and Social Media. Tutorial results can be provided to course instructors upon request. You can contact a librarian to request customized content for your classes. A librarian will respond to refine the content and format of your requested materials within one to two business days