Using CO 2 spatial variability to quantify representation errors of satellite CO 2 retrievals

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95625/1/grl24793.pd

Remote Sensing of CO2: Geostatistical Tools for Assessing Spatial Variability, Quantifying Representation Errors, and Gap-Filling.

Currently, approximately half of the anthropogenic emissions of CO2 are absorbed by oceans and the terrestrial biosphere, thus greatly reducing the rate of atmospheric CO2 increase and related climate change. The current understanding of the global carbon cycle, and of the sustainability of natural carbon sinks, is limited, however. To enhance this knowledge, scientists use process-based biospheric models and atmospheric transport models, together with the limited global ground-based CO2 measurement network to infer global CO2 fluxes. Current estimates of carbon budgets at regional to continental scales vary significantly, however, in large part due to limited atmospheric observations of CO2. Satellite-based observations provide the possibility of global coverage of column-averaged CO2 (XCO2), which could improve the precision of estimated CO2 fluxes. XCO2 observations will have large data gaps, however, which will limit the use of XCO2 observations for evaluating CO2 flux estimates. In addition, remote sensing soundings will often be representative of fine scales relative to the resolution of typical atmospheric transport models, causing representation errors that should be quantified for accurate CO2 flux estimation. In this dissertation, the spatial variability of the XCO2 signal is quantified using geostatistical analysis. Geostatistical methods that depend on the knowledge of this spatial variability are then presented for evaluating representation errors. Unlike previous estimates of representation errors, the proposed method accounts for the regionally-variable XCO2 spatial variability, and the spatial distribution of retrievals. Further, a spatial mixed-effects statistical model that best represents the quantified XCO2 variability is presented for gap-filling XCO2 retrievals. The presented geostatistical gap-filling method, which is based on a multi-resolution model of the spatial trend and variability of XCO2, is tested using eight realistic scenarios of expected spatial distributions of XCO2 retrievals. The method yields XCO2 estimates over regions with data gaps, together with an estimate of the associated gap-filling uncertainties. The presented methods provide flexible tools that can be applied to estimate representation errors and gap-fill XCO2 or other remotely sensed data. As such, they provide the potential for improving and evaluating estimated CO2 fluxes, process-based models, and atmospheric transport models.Ph.D.Environmental EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/62225/1/alanood_1.pd

Something borrowed, something new : challenges in using qualitative methods to study under-researched international business phenomena

This article responds to calls for IB researchers to study a greater diversity of international business (IB) phenomena in order to generate theoretical insights about empirical settings that are under-represented in the scholarly IB literature. While this objective is consistent with the strengths of qualitative research methods, novel empirical settings are not always well aligned with methods that have been developed in better-researched and thus more familiar settings. In this article, we explore three methods-related challenges of studying under-researched empirical settings, in terms of gathering and analyzing qualitative data. The challenges are: managing researcher identities, navigating unfamiliar data gathering conditions, and theorizing the uniqueness of novel empirical settings. These challenges are integral to the process of contextualization, which involves linking observations from an empirical setting to the categories of the theoretical research context. We provide a toolkit of recommended practices to manage them, by drawing on published accounts of research by others, and on our own experiences in the field.Cet article répond aux appels lancés aux chercheurs en affaires internationales (International Business - IB) à étudier une plus grande diversité de phénomènes en IB pour générer des renseignements théoriques sur des terrains empiriques sous-représentés dans la littérature de l’IB. Bien que cet objectif soit cohérent avec les points forts des méthodes de recherche qualitative, les nouveaux terrains empiriques ne sont pas toujours compatibles avec les méthodes développées dans des terrains mieux étudiés et donc plus familiers. Dans cet article, nous explorons trois défis liés aux méthodes de recherche sur les terrains empiriques peu étudiés, plus spécifiquement, à la collecte et l’analyse des données qualitatives. Les défis sont les suivants : gérer les identités des chercheurs, naviguer dans des conditions de collecte de données peu familières et théoriser le caractère unique des nouveaux terrains empiriques. Ces défis font partie intégrante du processus de contextualisation qui consiste à relier les observations sur un terrain empirique aux catégories théoriques. Pour les gérer, nous élaborons une « boîte à outils » de pratiques recommandées en nous appuyant sur des comptes rendus de recherche publiés par d'autres ainsi que sur nos propres expériences sur le terrain.Este artículo responde a los pedidos para que los investigadores de negocios internacionales estudien una mayor diversidad de fenómenos de negocios internacionales con el fin de generar conocimientos teóricos sobre entornos empíricos que están escasamente representados en la literatura académica de los negocios internacionales. Aunque este objetivo es consecuente con las fortalezas de los métodos de investigación cualitativa, los nuevos entornos empíricos no siempre están bien alineados con los métodos que se han desarrollado en entornos mejor investigados y, por ende, más familiares. En este artículo, exploramos tres desafíos relacionados con los métodos para estudiar entornos empíricos poco investigados, en términos de recopilación y análisis de datos cualitativos. Los retos son: la gestión de las identidades de los investigadores, la navegación por condiciones desconocidas de recopilación de datos y la teorización de la peculiaridad de los nuevos entornos empíricos. Estos retos son parte integral del proceso de contextualización, el cual implica vincular las observaciones de un entorno empírico a las categorías del contexto de investigación teórico. Proporcionamos una caja de herramientas de prácticas recomendadas para gestionarlas, basándonos en los reportajes de investigación publicados por otros y en nuestras propias experiencias en el campo.The Social Sciences and Humanities Research Council of Canada.https://link.springer.com/journal/41267hj2023Gordon Institute of Business Science (GIBS

Women's entrepreneurship in Saudi Arabia:feminist solidarity and political activism in disguise?'

This paper is a longitudinal study that uses insights from postcolonial feminism to explore women’s entrepreneurship as a political form of feminist organising for social change in Saudi Arabia. Postcolonial feminist approaches challenge Western feminism, which can obscure the diversity of women’s lived experiences, agency and activism. Through Bayat’s (2013) theory of 'quiet encroachment', I identify the ways in which contemporary Western conceptualisations of feminist solidarity and social movements have dismissed ‘Other’ women’s ‘silent’, protracted and (dis)organised activism in parts of the Middle East. By exploring how Saudi women have utilised their entrepreneurial space as a legitimate platform for change, I aim to enrich understanding of women’s activism through everyday solidarity practices, which allow them to quietly encroach onto the previously forbidden political space. The findings exemplify how their activism ‘quietly’ developed over time through a three- step process - from the entrepreneur aiming to empower women within their organisation, to developing feminist consciousness within their entrepreneurial network, to becoming a ‘political activist’ lobbying for policy changes for women. These solidarity practices exemplify the West’s relationship with ‘the Other’, and reveal that feminist organising for social change must be explored within its own context in order to fully appreciate its global political potential

A global evaluation of the regional spatial variability of column integrated CO 2 distributions

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95294/1/jgrd14612.pd

Digital girl:Cyberfeminism and the emancipation potential of digital entrepreneurship in emerging economies

Digital entrepreneurship has been described as a “great leveler” in terms of equalizing the entrepreneurial playing field for women. However, little is known of the emancipatory possibilities offered by digital entrepreneurship for women constrained by social and cultural practices such as male guardianship of female relatives and legally enforced gender segregation. In order to address this research gap, this paper examines women’s engagement in digital entrepreneurship in emerging economies with restrictive social and cultural practices. In so doing, we draw upon the analytical frameworks provided by entrepreneurship as emancipation and cyberfeminism. Using empirical data from an exploratory investigation of entrepreneurship in Saudi Arabia, we examine how women use digital technologies in the pursuit of entrepreneurial opportunities. Our findings reveal that women in Saudi Arabia use digital entrepreneurship to transform their embodied selves and lived realities rather than to escape gender embodiment as offered by the online environment

Precision requirements for space-based XCO2 data

Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 112 (2007): D10314, doi:10.1029/2006JD007659.Precision requirements are determined for space-based column-averaged CO2 dry air mole fraction (XCO2) data. These requirements result from an assessment of spatial and temporal gradients in XCO2, the relationship between XCO2 precision and surface CO2 flux uncertainties inferred from inversions of the XCO2 data, and the effects of XCO2 biases on the fidelity of CO2 flux inversions. Observational system simulation experiments and synthesis inversion modeling demonstrate that the Orbiting Carbon Observatory mission design and sampling strategy provide the means to achieve these XCO2 data precision requirements.This work was supported by the Orbiting Carbon Observatory (OCO) project through NASA’s Earth System Science Pathfinder (ESSP) program. SCO and JTR were supported by a NASA IDS grant (NAG5-9462) to JTR

AfriMTE and AfriCOMET : Empowering COMET to Embrace Under-resourced African Languages

Despite the progress we have recorded in scaling multilingual machine translation (MT) models and evaluation data to several under-resourced African languages, it is difficult to measure accurately the progress we have made on these languages because evaluation is often performed on n-gram matching metrics like BLEU that often have worse correlation with human judgments. Embedding-based metrics such as COMET correlate better; however, lack of evaluation data with human ratings for under-resourced languages, complexity of annotation guidelines like Multidimensional Quality Metrics (MQM), and limited language coverage of multilingual encoders have hampered their applicability to African languages. In this paper, we address these challenges by creating high-quality human evaluation data with a simplified MQM guideline for error-span annotation and direct assessment (DA) scoring for 13 typologically diverse African languages. Furthermore, we develop AfriCOMET, a COMET evaluation metric for African languages by leveraging DA training data from high-resource languages and African-centric multilingual encoder (AfroXLM-Roberta) to create the state-of-the-art evaluation metric for African languages MT with respect to Spearman-rank correlation with human judgments (+0.406)

Something borrowed, something new : challenges in using qualitative methods to study under-researched international business phenomena

This article responds to calls for IB researchers to study a greater diversity of international business (IB) phenomena in order to generate theoretical insights about empirical settings that are under-represented in the scholarly IB literature. While this objective is consistent with the strengths of qualitative research methods, novel empirical settings are not always well aligned with methods that have been developed in better-researched and thus more familiar settings. In this article, we explore three methods-related challenges of studying under-researched empirical settings, in terms of gathering and analyzing qualitative data. The challenges are: managing researcher identities, navigating unfamiliar data gathering conditions, and theorizing the uniqueness of novel empirical settings. These challenges are integral to the process of contextualization, which involves linking observations from an empirical setting to the categories of the theoretical research context. We provide a toolkit of recommended practices to manage them, by drawing on published accounts of research by others, and on our own experiences in the field