GPS radio occultation with GRACE: Atmospheric profiling utilizing the zero difference technique

Radio occultation events recorded on 28-29 July 2004 by a GPS receiver aboard the GRACE-B satellite are analyzed. The stability of the receiver clock allows for the derivation of excess phase profiles using a zero difference technique, rendering the calibration procedure with concurrent observations of a reference GPS satellite obsolete. 101 refractivity profiles obtained by zero differencing and 96 profiles calculated with an improved single difference method are compared with co-located ECMWF meteorological analyses. Good agreement is found at altitudes between 5 and 30 km with an average fractional refractivity deviation below 1% and a standard deviation of 2-3%. Results from end-to-end simulations are consistent with these observations.Comment: 17 pages, 4 figure

Global monitoring of tropospheric water vapor with GPS radio occultation aboard CHAMP

The paper deals with application of GPS radio occultation (RO) measurements aboard CHAMP for the retrieval of tropospheric water vapor profiles. The GPS RO technique provides a powerful tool for atmospheric sounding which requires no calibration, is not affected by clouds, aerosols or precipitation, and provides an almost uniform global coverage. We briefly overview data processing and retrieval of vertical refractivity, temperature and water vapor profiles from GPS RO observations. CHAMP RO data are available since 2001 with up to 200 high resolution atmospheric profiles per day. Global validation of CHAMP water vapor profiles with radiosonde data reveals a bias of about 0.2 g/kg and a standard deviation of less than 1 g/kg specific humidity in the lower troposphere. We demonstrate potentials of CHAMP RO retrievals for monitoring the mean tropospheric water vapor distribution on a global scale.Comment: 7 pages, 4 figure

Can GNSS reflectometry detect precipitation over oceans?

For the first time, a rain signature in Global Navigation Satellite System Reflectometry (GNSS‐R) observations is demonstrated. Based on the argument that the forward quasi‐specular scattering relies upon surface gravity waves with lengths larger than several wavelengths of the reflected signal, a commonly made conclusion is that the scatterometric GNSS‐R measurements are not sensitive to the surface small‐scale roughness generated by raindrops impinging on the ocean surface. On the contrary, this study presents an evidence that the bistatic radar cross section σ0 derived from TechDemoSat‐1 data is reduced due to rain at weak winds, lower than ≈ 6 m/s. The decrease is as large as ≈ 0.7 dB at the wind speed of 3 m/s due to a precipitation of 0–2 mm/hr. The simulations based on the recently published scattering theory provide a plausible explanation for this phenomenon which potentially enables the GNSS‐R technique to detect precipitation over oceans at low winds

Endividamento externo no Brasil: origens e consequências (1964-2006)

TCC (graduação) - Universidade Federal de Santa Catarina. Centro Sócio-Econômico. Economia.A dívida externa brasileira foi um dos elementos mais discutidos na segunda metade do século XX no cenário econômico brasileiro. A ditadura militar optou por uma política de endividamento para desenvolver todo o parque industrial brasileiro e promover o crescimento fantástico que o mundo todo viu com o “milagre” ocorrido no período de 1968 a 1974. Mas a estratégia que aparentemente não tinha limite para a obtenção de crédito externo passou a demonstrar todas as suas conseqüências depois dos choques do preço do petróleo, não só para o Brasil como para vários países da América Latina. A repressão cultural e política da ditadura não impediu o surgimento de questionamentos a cerca do modo mais adequado de governar o país sob pontos de vista tão diversos como o jurídico, contábil, econômico ou político. Como nos anos 80 não se chegou a uma conclusão, esses movimentos se transformaram assumindo outras formas derivadas destes nos anos 90, que continuam cada um a sua forma procurando debater um tema tão complexo. Assim, utilizou-se o balanço de pagamentos brasileiro para acompanhar os movimentos que levaram ao aumento da dívida externa, procurando correlacionar estes aos fatos históricos para vermos as influências de um sobre o outro e vice-versa. Após mostraremos os argumentos das duas principais correntes da atualidade para auxiliar na discussão sobre o pagamento ou não-pagamento da dívida

Evaluation of E Layer Dominated Ionosphere Events Using COSMIC/FORMOSAT-3 and CHAMP Ionospheric Radio Occultation Data

At certain geographic locations, especially in the polar regions, the ionization of the ionospheric E layer can dominate over that of the F2 layer. The associated electron density profiles show their ionization maximum at E layer heights between 80 and 150 km above the Earth’s surface. This phenomenon is called the “E layer dominated ionosphere” (ELDI). In this paper we systematically investigate the characteristics of ELDI occurrences at high latitudes, focusing on their spatial and temporal variations. In our study, we use ionospheric GPS radio occultation data obtained from the COSMIC/FORMOSAT-3 (Constellation Observing System for Meteorology, Ionosphere, and Climate/Formosa Satellite Mission 3) and CHAMP (Challenging Minisatellite Payload) satellite missions. The entire dataset comprises the long period from 2001 to 2018, covering the previous and present solar cycles. This allows us to study the variation of the ELDI in different ways. In addition to the geospatial distribution, we also examine the temporal variation of ELDI events, focusing on the diurnal, the seasonal, and the solar cycle dependent variation. Furthermore, we investigate the spatiotemporal dependency of the ELDI on geomagnetic storms

Reconsidering the ‘Symmetry’ Between Institutionalization and Professionalization: The Case of Corporate Social Responsibility Managers

The assumption of a mutually supportive, ‘symmetric’ relationship between institutionalization and professionalization is central to the institutionalist perspective on professional work. Our inductive qualitative study of corporate social responsibility (CSR) managers in multinational corporations (MNCs) prompts to rethink the validity of this assumption. We show that as the institutionalization of CSR advances and consolidates, CSR managers are pushed to the organizational periphery. This indicates that the relationship between professionalization and institutionalization can be ‘asymmetric’ under certain conditions. To advance the study of this asymmetry, we develop a conceptual framework and a set of corresponding propositions that explain why some groups are able to advance their professionalization projects, while others cannot. Our study makes three main contributions to the literature: First, we explicate under which conditions the relationship between institutionalization and professionalization is more likely asymmetric than symmetric. Second, our explanation of the shifting organizational positions of different professional groups allows for further delineating occupational from organizational professionals. Third, we contribute to the CSR literature by examining the dynamic yet ambiguous role of CSR managers as driving forces behind the implementation of CSR

Perfil profissional dos trabalhadores na percepção de gestores de empresas do Vale do Taquari-RS

A competência profissional vem sendo considerada um fator essencial para a competitividade das empresas, que sofrem constantes mudanças estabelecidas pelo ambiente em que estão inseridas. Neste contexto, o objetivo desta pesquisa, de abordagem quantitativa e descritiva, foi identificar o perfil profissional dos trabalhadores requerido pelos gestores de empresas do Vale do Taquari-RS. Por meio de um questionário estruturado, com uma amostra de 67 gestores de empresas dos segmentos industrial, comercial e de prestação de serviços, os dados foram coletados e, após, analisados através da técnica estatística média ponderada. Os resultados oferecem indícios de que o perfil profissional dos trabalhadores, na percepção de gestores, é deficitário

The mystery-religions and their influence upon Paul's conception of Christian belief

Thesis (M.A.)--Boston University This item was digitized by the Internet Archive