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.

Juana Manuela Gorriti. Cincuenta y tres cartas inéditas a Ricardo Palma. Fragmentos de lo íntimo. Buenos Aires-Lima 1882-1891, de Graciela Batticuore

Fil: Sancholuz, Carolina. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Enemigos declarados de nuestro sistema. La acción política contrarrevolucionaria de Diego de Agüero y Miguel Fernández de Agüero (1770-1816)

Este artículo analiza a la fuerza social contrarrevolucionaria de la Buenos Aires tardo colonial. Toma como observables a dos de sus principales dirigentes: los comerciantes monopolistas españoles Diego de Agüero y Miguel Fernández de Agüero. Los Agüero poseían una estrategia política definida: oponerse al proceso revolucionario y defender el orden colonial. Dicho programa fue construyéndose a lo largo de más de treinta años, en los que pasan de una alianza reformista a enfrentarse política y militarmente contra los revolucionarios. En este recorrido, resultan una bisagra los enfrentamientos en torno al tráfico de cueros con naciones extranjeras, en el que defienden el comercio legal por la vía de Cádiz, argumentando que se trata de uno de los bastiones de la Monarquía. Dicho programa se vincula con su reproducción social, basada en un privilegio político otorgado por el Estado colonial. Su destrucción, por acción de la Revolución, producirá su derrota comercial, política y militar

El acuerdo político de 1891 y la candidatura presidencial del doctor Luis Sáenz Peña

Fil: Barba, Fernando Enrique. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.