Assessment of the structure and variability of Weddell Sea water masses in distinct ocean reanalysis products

We assessed and evaluated the performance of five ocean reanalysis products in reproducing essential hydrographic properties and their associated temporal variability for the Weddell Sea, Antarctica. The products used in this assessment were ECMWF ORAS4 (European Centre for Medium-Range Weather Forecasts Ocean Reanalysis System 4), CFSR (Climate Forecast System Reanalysis), MyOcean UR025.4 (University of Reading), ECCO2 (Estimating the Circulation and Climate of the Ocean, Phase II) and SODA (Simple Ocean Data Assimilation). The present study focuses on the Weddell Sea deep layer, which is composed of the following three main water masses: Warm Deep Water (WDW), Weddell Sea Deep Water (WSDW) and Weddell Sea Bottom Water (WSBW). The MyOcean UR025.4 product provided the most accurate representation of the structure and thermohaline properties of the Weddell Sea water masses when compared with observations. All the ocean reanalysis products analyzed exhibited limited capabilities in representing the surface water masses in the Weddell Sea. The CFSR and ECCO2 products were not able to represent deep water masses with a neutral density ? 28.40 kg m?3, which was considered the WSBW's upper limit throughout the simulation period. The expected WDW warming was only reproduced by the SODA product, whereas the ECCO2 product was able to represent the trends in the WSDW's hydrographic properties. All the assessed ocean reanalyses were able to represent the decrease in the WSBW's density, except the SODA product in the inner Weddell Sea. Improvements in parameterization may have as much impact on the reanalyses assessed as improvements in horizontal resolution primarily because the Southern Ocean lacks in situ data, and the data that are currently available are summer-biased. The choice of the reanalysis product should be made carefully, taking into account the performance, the parameters of interest, and the type of physical processes to be evaluated

El déficit de la línea legal en el PRT-ERP : Algunas tensiones para pensar las resoluciones frente al GAN y la apertura política

Este trabajo, presentado como un avance preliminar de investigación sobre un tema puntual, no tiene mayor pretensión que presentar algunas líneas analíticas sobre un desarrollo más amplio: las tensiones al interior del PRT-ERP en cuanto a sus formas de actuación y resolución de los interrogantes (aquí entendemos que los hay permanentemente) en el contexto que se abre desde el llamado al Gran Acuerdo Nacional (GAN) y las elecciones de 1973. Este avance, tiene por objeto poder pensar y empezar a configurar algunas futuras líneas de trabajo. Tomaremos algunos documentos de la organización que refieran a la coyuntura mencionada (Boletines Internos, reuniones de Comité Ejecutivo, revista El Combatiente, etc.) donde puedan apreciarse las tensiones entre las formas y las posibilidades de acción, así como también sobre las posteriores evaluaciones de las mismas, en el transcurso de esos años.Facultad de Humanidades y Ciencias de la Educació

A numerical study of the Southern Ocean including a thermodynamic active ice shelf - Part 1: Weddell Sea

There is a great amount of uncertainty regarding the understanding of the atmosphere-ocean-cryosphere interactions in the Southern Ocean despite the role that the region plays in our changing climate. With the aim of studying the relative importance of sea-ice and ice shelf processes in the Southern Ocean, a coupled ocean circulation sea-ice/ice shelf cavity model based on the Regional Ocean Model System (ROMS) is used in a periodic circumpolar domain with enhanced resolution in the Weddell Sea. A hierarchy of numerical experiments is performed where first a sea-ice model is used and then an ice shelf thermodynamic parameterization is included in order to evaluate the improvements resulting from each component. Results show that it is necessary to consider the formation and melting of sea-ice in order to adequately reproduce the observed hydrography and circulation. Inclusion of ice shelves cavities in the model only improves results if the ice shelf-ocean thermodynamic fluxes are active. Ice shelves and ocean interactions are an important process to be considered in order to obtain realistic hydrographic values under the ice shelf. The model framework presented in this work is a promising tool for analyzing the Southern Ocean response to future climate change scenarios

A Pilot Study with a Novel Setup for Collaborative Play of the Humanoid Robot KASPAR with children with autism

This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.This article describes a pilot study in which a novel experimental setup, involving an autonomous humanoid robot, KASPAR, participating in a collaborative, dyadic video game, was implemented and tested with children with autism, all of whom had impairments in playing socially and communicating with others. The children alternated between playing the collaborative video game with a neurotypical adult and playing the same game with the humanoid robot, being exposed to each condition twice. The equipment and experimental setup were designed to observe whether the children would engage in more collaborative behaviours while playing the video game and interacting with the adult than performing the same activities with the humanoid robot. The article describes the development of the experimental setup and its first evaluation in a small-scale exploratory pilot study. The purpose of the study was to gain experience with the operational limits of the robot as well as the dyadic video game, to determine what changes should be made to the systems, and to gain experience with analyzing the data from this study in order to conduct a more extensive evaluation in the future. Based on our observations of the childrens’ experiences in playing the cooperative game, we determined that while the children enjoyed both playing the game and interacting with the robot, the game should be made simpler to play as well as more explicitly collaborative in its mechanics. Also, the robot should be more explicit in its speech as well as more structured in its interactions. Results show that the children found the activity to be more entertaining, appeared more engaged in playing, and displayed better collaborative behaviours with their partners (For the purposes of this article, ‘partner’ refers to the human/robotic agent which interacts with the children with autism. We are not using the term’s other meanings that refer to specific relationships or emotional involvement between two individuals.) in the second sessions of playing with human adults than during their first sessions. One way of explaining these findings is that the children’s intermediary play session with the humanoid robot impacted their subsequent play session with the human adult. However, another longer and more thorough study would have to be conducted in order to better re-interpret these findings. Furthermore, although the children with autism were more interested in and entertained by the robotic partner, the children showed more examples of collaborative play and cooperation while playing with the human adult.Peer reviewe