Asian outflow and trans-Pacific transport of carbon monoxide and ozone pollution: An integrated satellite, aircraft, and model perspective

Satellite observations of carbon monoxide (CO) from the Measurements of Pollution in the Troposphere (MOPITT) instrument are combined with measurements from the Transport and Chemical Evolution Over the Pacific (TRACE-P) aircraft mission over the northwest Pacific and with a global three-dimensional chemical transport model (GEOS-CHEM) to quantify Asian pollution outflow and its trans-Pacific transport during spring 2001. Global CO column distributions in MOPITT and GEOS-CHEM are highly correlated (R2 = 0.87), with no significant model bias. The largest regional bias is over Southeast Asia, where the model is 18% too high. A 60% decrease of regional biomass burning emissions in the model (to 39 Tg yr−1) would correct the discrepancy; this result is consistent with TRACE-P observations. MOPITT and TRACE-P also give consistent constraints on the Chinese source of CO from fuel combustion (181 Tg CO yr−1). Four major events of trans-Pacific transport of Asian pollution in spring 2001 were seen by MOPITT, in situ platforms, and GEOS-CHEM. One of them was sampled by TRACE-P (26–27 February) as a succession of pollution layers over the northeast Pacific. These layers all originated from one single event of Asian outflow that split into northern and southern plumes over the central Pacific. The northern plume (sampled at 6–8 km off California) had no ozone enhancement. The southern subsiding plume (sampled at 2–4 km west of Hawaii) contained a 8–17 ppbv ozone enhancement, driven by decomposition of peroxyacetylnitrate (PAN) to nitrogen oxides (NOx). This result suggests that PAN decomposition in trans-Pacific pollution plumes subsiding over the United States could lead to significant enhancements of surface ozone

Reflections on a crisis: political disenchantment, moral desolation, and political integrity

Declining levels of political trust and voter turnout, the shift towards populist politics marked by appeals to ‘the people’ and a rejection of ‘politics-as-usual’, are just some of the commonly cited manifestations of our culture of political disaffection. Democratic politics, it is argued, is in crisis. Whilst considerable energy has been expended on the task of lamenting the status of our politics and pondering over recommendations to tackle this perceived crisis, amid this raft of complaints and solutions lurks confusion. This paper seeks to explore the neglected question of what the precise nature of the crisis with which we are confronted involves, and, in so doing, to go some way towards untangling our confusion. Taking my cue from Machiavelli and his value-pluralist heirs, I argue that there is a rift between a morally admirable and a virtuous political life. Failure to appreciate this possibility causes narrations of crisis to misconstrue the moral messiness of politics in ways that lead us to misunderstand how we should respond to disenchantment. Specifically, I suggest that: (i) we think that there is a moral crisis in politics because we have an unsatisfactorily idealistic understanding of political integrity in the first place; and (ii) it is a mistake to imagine that the moral purification of politics is possible or desirable. Put simply, our crisis is not moral per se but primarily philosophical in nature: it relates to the very concepts we employ—the qualities of character and context we presuppose whilst pondering over political integrity

Impact of Optimized Breastfeeding on the Costs of Necrotizing Enterocolitis in Extremely Low Birthweight Infants

To estimate risk of NEC for ELBW infants as a function of preterm formula and maternal milk (MM) intake and calculate the impact of suboptimal feeding on NEC incidence and costs

Shifting the Power Dynamic - Does Grading by Near-Peer Mentors Impact their Effectiveness?

This work-in-progress paper proposes a study that examines the effects of grading on the role of near peer mentors (NPMs). Two well-developed near peer mentoring models, Supplemental Instruction (SI) and the Learning Assistants (LA) Program do not allow their SI Leaders or LAs to grade student work. This separation in roles prevents a power dynamic between the student and the SI Leaders/LAs from forming where the Leader/LAs have perceived control over student success. At Michigan Technological University, teaching assistants were used in our first-year engineering courses; however, in a course redesign in 2017, the teaching assistant role was converted into a near-peer mentoring (NPM) role that retained grading responsibilities. Our NPMs, who we call LEarning with Academic Partners (LEAP) Leaders, have reported that they find value in grading their students\u27 work as it helps them to plan activities to best suit their students\u27 needs. Additionally, grading allows an opportunity to more closely monitor student submissions and to more quickly identify and intervene when a student is lagging behind.This proposed study will examine the effects of LEAP Leaders grading their students\u27 work on: 1) the Leader\u27s ability to help their students and 2) the relationships between the Leaders and their students

Work in progress - What are you thinking? Over confidence in first year students

Michigan Technological University is one of the nation\u27s largest engineering schools (900+ first year students) and houses a large common first year engineering curriculum. The purpose of this curriculum is to introduce many of the fundamental components of engineering. One of these components is the use of modern computational and programming tools to solve engineering problems. This paper continues a long-term study that began in 2007 and focuses on student confidence with the use of computational tools. On the first day of class, students were surveyed on their proficiency with the use of spreadsheets. Students self reported levels of proficiency from expert to no experience. Students were then asked a simple question regarding a spreadsheet cell equation. Over three years only 16% of the students were correct, while 90% self ranked as familiar or better. A gender bias was noted as women under estimated their skills while men overestimated their own abilities. This study contributes to the growing body of knowledge of gender confidence gaps. Additionally, it lays the groundwork for creating an assessment plan to identify the preparedness of incoming students and measure their skill at the end of the course. © 2010 IEEE

A modeling study of the impact of winter-spring arctic outflow on the NO \u3c inf\u3e x and O \u3c inf\u3e 3 budgets of the North Atlantic troposphere

[1] In this study, we determine the impact of winter-spring arctic outflow events on the budgets of tropospheric NOx and ozone over the North Atlantic Ocean. An updated version of the NCAR Master-Mechanism, a detailed, explicit photochemical model, is applied to trajectories representative of arctic outflow for the months of January through May. During the simulations, peroxyacetyl nitrate (PAN) mixing ratios drop by up to 270 pptv, increasing NOx levels up to 120 pptv. However, the released NOx is quickly destroyed by efficient NOx loss reactions leading to formation of HNO3 and, to a lesser extent, nitroaromatic compounds. As a result of elevated NOx, O3 levels are increased. The resulting net impact on the flux of O3 to the North Atlantic is estimated to be less than 712 Gg O3/month. While this source is similar in magnitude to estimates of ozone produced from aircraft emissions, both are small in comparison to the export of ozone from North America. Therefore, we conclude that while elevated levels of pollutants in arctic outflow increase the levels of NOx and O3 in the North Atlantic region, on a seasonal basis the impact on the budgets of NOx and O3 in this region is small. Copyright 2002 by the American Geophysical Union

Supplemental Instruction in a First-Year Engineering Course: A study from the Learning with Academic Partners (LEAP) Program

This innovative practice full paper reviews the formation and effects of the LEarning with Academic Partners (LEAP) program at Michigan Technological University in the first two years of operation. The LEAP Program combines the job requirements of a traditional Teaching Assistant (TA) with those of a Supplemental Instruction (SI) Leader. While each program has their benefits, to date, no one has evaluated the effects of a combined program such as the one established at Michigan Tech. To determine these effects, we focused our analysis on measuring course performance and student attitudes of student groups in a second semester first-year engineering course, ENG1102 - Engineering Modeling and Design: Spring 2017 (no LEAP), Spring 2017 (no LEAP/pilot LEAP with optional attendance), and 2018 (LEAP with mandatory attendance)

Transport of ozone precursors from the Arctic troposphere to the North Atlantic region

The importance of Arctic outflow events to the budgets of nitrogen oxides and hydrocarbons in the North Atlantic region is estimated using a climatology of isentropic airflow trajectories, in combination with current understanding of the levels of these compounds in the Arctic troposphere. We first review available measurements of nonmethane hydrocarbons (NMHCs), total reactive oxidized nitrogen (NOy), and major NOy species in the Arctic troposphere to develop best estimate average vertical profiles during January-May outflow events. Measurements of these compounds in the winter-spring Arctic are generally consistent. Average levels during March are ≥500 parts per 1012 by volume (NOy) and ∼20 parts per billion carbon (NMHC). Current evidence for a significant vertical gradient above the boundary layer is weak, although additional measurements are needed. Secondly, the flow patterns and frequency of Arctic outflow events which reach the North Atlantic region south of 50°-55°N are investigated using an 11-year climatology of isentropic forward trajectories originating at 70°N in the months of January-May. The dominant route of trajectories reaching the temperate North Atlantic originates north of Canada at 2-6 km altitude and continues southward along a semipermanent trough located near the East Coast of North America. Trajectories reaching the temperate North Atlantic originated in this region on ∼70% of the days analyzed. Significant subsidence occurs during the southward flow, resulting in warming conducive to photochemical processing of the Arctic pollutants. Based on these analyses, the southward fluxes of NOy, and NMHCs out of the Arctic in events which reach the North Atlantic south of 50°N total 7.3 GgN/month NOy and 250 GgC/month NMHC during March. These values are biased low as they include only those trajectories originating below 6 km and exclude trajectories which pass over the United States or southeastern Canada. The calculated NOy flux during May is lower but may be underestimated due to uncertainty in conditions in the Arctic free troposphere in that month. The May flux of NMHCs is larger than that in March as a result of a more frequent occurrence of outflow events. These fluxes impact air parcels which are not affected by direct transport from source regions and appear to be seasonally significant relative to other sources of ozone precursors to the North Atlantic troposphere. If a significant fraction of the peroxyacetyl nitrate and alkyl nitrates which comprise most of the advected NOy decomposes over the North Atlantic, the transport of anthropogenic pollutants through the Arctic may play a significant role in the ozone budget of the North Atlantic troposphere

BIRD USE OF RIPARIAN VEGETATION ALONG THE TRUCKEE RIVER, CALIFORNIA AND NEVADA

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