Horizontal profiles of longwave and shortwave radiation components over sea ice near Barrow, Alaska during the 2011 melt

An integrated instrument package for measuring and understanding the surface radiation budget of sea ice is presented, along with results from its first deployment. The setup simultaneously measures broadband fluxes of upwelling and downwelling terrestrial and solar radiation (four components separately), spectral fluxes of incident and reflected solar radiation, and supporting data such as air temperature and humidity, surface temperature, and location (GPS), in addition to photographing the sky and observed surface during each measurement. The instruments are mounted on a small sled, allowing measurements of the radiation budget to be made at many locations in the study area to see the effect of small-scale surface processes on the large-scale radiation budget. Such observations have many applications, from calibration and validation of remote sensing products to improving our understanding of surface processes that affect atmosphere-snow-ice interactions and drive feedbacks, ultimately leading to the potential to improve climate modelling of ice-covered regions of the ocean. The photographs, spectral data, and other observations allow for improved analysis of the broadband data. An example of this is shown by using the observations made during a partly cloudy day, which show erratic variations due to passing clouds, and creating a careful estimate of what the radiation budget along the observed line would have been under uniform sky conditions, clear or overcast. Other data from the setup's first deployment, in June 2011 on fast ice near Point Barrow, Alaska, are also shown; these illustrate the rapid changes of the radiation budget during a cold period that led to refreezing and new snow well into the melt season.

Tierra, comercio y gobierno en el surgimiento de los pueblos bonaerenses : Juan Lorenzo Castro, hacendado, pulpero y alcalde de Chascomús, 1802-1820

Fil: Banzato, Guillermo. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina.

Marcus Mota. A dramaturgia musical de Esquilo, Editora Universidade de Brasília, Brasilia, 2008, 568 pp.

Fil: Fernández Deagustini, María del Pilar. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

El pensamiento agrario ilustrado en el Río de la Plata : Un estudio del Semanario de Agricultura, Industria y Comercio (1802-1807)

A partir del estudio detenido del Semanario de Agricultura, Industria y Comercio, editado por Juan Hipólito Vieytes entre 1802 y 1807, en este trabajo se plantean las líneas centrales del pensamiento reformista ilustrado. Específicamente, se analizan las nuevas ideas del discurso económico, con la gradual incorporación del liberalismo a partir de la fisiocracia y el discurso clásico de Adam Smith, y más específicamente aún, las propuestas para mejorar y aumentar la producción agropecuaria surgidas de ese pensamiento reformista. Además, se analizan diversas dimensiones del incipiente discurso periodístico, como su estrategia de difusión y los actores involucrados, el énfasis los saberes prácticos y la transmisión de ideas de origen europeo y los cambios que se dieron en el propio periódico.

Autonomia e hierarquia em duas comunidades de escravos : Os casos George (Alabama, Estados Unidos, 1847) e Lino (Vassouras, Brasil, 1871)

This article seeks argue that the search for autonomy among slaves necessarily created hierarchies within the community where they were inserted. Through two cases compared, George in U.S. and Lino in Brazil, seeks to show that a notion of slave community was built by the social actors who were part of it