Performance of downscaled regional climate simulations using a variable-resolution regional climate model : Tasmania as a test case

In this study we develop methods for dynamically downscaling output from six general circulation models (GCMs) for two emissions scenarios using a variable-resolution atmospheric climate model. The use of multiple GCMs and emissions scenarios gives an estimate of model range in projected changes to the mean climate across the region. By modeling the atmosphere at a very fine scale, the simulations capture processes that are important to regional weather and climate at length scales that are subgrid scale for the host GCM. We find that with a multistaged process of increased resolution and the application of bias adjustment methods, the ability of the simulation to reproduce observed conditions improves, with greater than 95% of the spatial variance explained for temperature and about 90% for rainfall. Furthermore, downscaling leads to a significant improvement for the temporal distribution of variables commonly used in applied analyses, reproducing seasonal variability in line with observations. This seasonal signal is not evident in the GCMs. This multistaged approach allows progressive improvement in the skill of the simulations in order to resolve key processes over the region with quantifiable improvements in the correlations with observations

Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Angstrom. Significant diversity is seen in the near maximum-light spectra (~ 2000--3500 Angstrom) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in uvw1/F250W are found to correlate with the B-band light-curve shape parameter dm15(B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., ~0.4 mag versus ~0.2 mag for those with 0.8 < dm15 < 1.7 mag). SN 2004dt is found as an outlier of this correlation (at > 3 sigma), being brighter than normal SNe Ia such as SN 2005cf by ~0.9 mag and ~2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects.Comment: 17 pages, 13 figures, accepted by Ap

Evaluating social & ubiquitous human-robot interaction

Presented at the 7th International Conference on Ubiquitous Robots and Ambient Intelligence (URAI 2010), Busan, Korea, 24th-27th November, 2010While many robotic initiatives now share the thesis that robots are a compelling instance of those artefacts which comprise and deliver smart and ubiquitous environments, reconciling the social interface aspect with pervasiveness and ubiquity still remains a largely unexplored area of research. We argue that specific studies must be carried out to explore possible inconsistencies between the keystones of social human-robot interaction and the new features exhibited by ubiquitous robots. To this end, we conducted a pilot study to explore how the ubiquity of a robot’s sensing capabilities affects the unconscious human perception of the robot as a social partner. Specifically, the experiment investigates whether people prefer a robot exhibiting ubiquitous sensor access or a more traditional robot whose capabilities are confined to its on-board sensors. We report qualitative results from the experiment and how results from the pilot study affect the design of the full-scale experiment.Science Foundation IrelandThis paper should be published in the conference proceedings but I was not able to locate them; copyright was transferred to KROS, permission granted. URAI website: http://www.kros.org/urai2010/ - AV 14/02/201

Using mixed reality agents as social interfaces for robots

The 16th IEEE International Symposium on Robot and Human Interactive Communication 2007 (IEEE RO-MAN 2007), Jeju Island, Korea, August, 2007Endowing robots with a social interface is often costly and difficult. Virtual characters on the other hand are comparatively cheap and well equipped but suffer from other difficulties, most notably their inability to interact with the physical world. This paper details our wearable solution to combining physical robots and virtual characters into a mixed reality agent (MiRA) through mixed reality visualisation. It describes a pilot study demonstrating our system, and showing how such a technique can offer a viable alternative cost effective approach to enabling a rich social interface for human-robot interaction.TS 09.08.1

Derivation of Shortwave Radiometric Adjustments for SNPP and NOAA-20 VIIRS for the NASA MODIS-VIIRS Continuity Cloud Products

Climate studies, including trend detection and other time series analyses, necessarily require stable, well-characterized and long-term data records. For satellite-based geophysical retrieval datasets, such data records often involve merging the observational records of multiple similar, though not identical, instruments. The National Aeronautics and Space Administration (NASA) cloud mask (CLDMSK) and cloud-top and optical properties (CLDPROP) products are designed to bridge the observational records of the Moderate-resolution Imaging Spectroradiometer (MODIS) onboard NASA’s Aqua satellite and the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the joint NASA/National Oceanic and Atmospheric Administration (NOAA) Suomi National Polar-orbiting Partnership (SNPP) satellite and NOAA’s new generation of operational polar-orbiting weather platforms (NOAA-20+). Early implementations of the CLDPROP algorithms on Aqua MODIS and SNPP VIIRS suffered from large intersensor biases in cloud optical properties that were traced back to relative radiometric inconsistency in analogous shortwave channels on both imagers, with VIIRS generally observing brighter top-of-atmosphere spectral reflectance than MODIS (e.g., up to 5% brighter in the 0.67 µm channel). Radiometric adjustment factors for the SNPP and NOAA-20 VIIRS shortwave channels used in the cloud optical property retrievals are derived from an extensive analysis of the overlapping observational records with Aqua MODIS, specifically for homogenous maritime liquid water cloud scenes for which the viewing/solar geometry of MODIS and VIIRS match. Application of these adjustment factors to the VIIRS L1B prior to ingestion into the CLDMSK and CLDPROP algorithms yields improved intersensor agreement, particularly for cloud optical properties

Ubiquitous realities through situated social agents

18th International Conference on Computer Animation and Social Agents (CASA 2005), Hong Kong, China, October 17-25, 2005In order to take the developing field of Social Robotics a stage further, this work investigates mixed reality in embodied social agents. The Virtual Robotic Workbench is employed which provides a versatile framework for experimentation in interoperability and cooperation between heterogeneous robots (real, simulated and virtual) and humans in multi-reality domains. Explicit social interaction, both between virtual and real robots and between robots and people, is supported.TS 09.08.1

Fusing realities in human-robot social interaction

37th International Symposium on Robotics ISR/Robotik , Munich, Germany, May, 2006As robots become more and more embedded in our physical and social environment, their integration into our social interaction space necessitates mechanisms which manage these new social contexts. While considerable work has been invested in developing strong human-like robots in order to arguably augment the human-robot interaction experience, the core complexity and significant costs with such an approach render it difficult to justify for practical real-world applications. This paper discusses the use of augmented reality as a tool to bypass this issue and allow the designer, and subsequent user, to easily choose an aesthetic with associated social behavioural mechanisms. Not only does this allow a user to perceive an associated form with a robot, but also allows many people to perceive alternate forms for the same robot, a degree of social customisation which has been impossible until now.TS 13.08.1

Performance of CrIS on Suomi – NPP

This presentation will review various recent analyses and results of early checkout activities to characterize the performance of CrIS on the NPP satellite