Improving Operational Geomagnetic Index Forecasting

Space weather prediction is moving from an era of pure curiosity-driven research into an era of 24/7 operations. The interest in space weather forecasts has never been greater, with society becoming ever more reliant upon technology and infrastructure which are potentially at risk. Amongst space weather hazards, geomagnetic storms are potential threats to power-grid infrastructure, communication systems and oil and gas operations. Geomagnetic indices capture the severity of magnetic storms by summarising magnetic activity at spatially disparate locations. They have become almost ubiquitous as parameterisations of storm-time magnetic conditions and are required inputs for radiation belt,ionospheric and neutral atmosphere models. We present the first results from a study aiming to provide operational geomagnetic index prediction that is: robust and reliable, has high cadence, runs fast enough for real-time operations , and is accurate forecasting up to three days ahead. The predictive power of autoregressive and machine-learning techniques applied to combinations of solar, solar wind and geomagnetic data is investigated. The predictions presented will ultimately form part of the British Geological Survey’s space weather forecast operations

ROSIE Findings 2: summary of 1-year outcomes: detoxification modality.

The Research Outcome Study in Ireland (ROSIE) is the first national, prospective, longitudinal, multi-site drug treatment outcome study in the country. The National Advisory Committee on Drugs (NACD) commissioned this research in 2002 as required by the National Drugs Strategy Action 99. The aim of the Study is to recruit and follow opiate users entering treatment over a period of time documenting the changes observed. Detoxification cohort: follow-up rates: Of the 81 people recruited within the detoxification modality, 93% (n=75) were located, and 77% (n=62) successfully completed a 1-year interview. One individual died within the follow-up period, four people withdrew from the study, eight people were located but not successfully interviewed, and an additional six participants were not located. These 19 people ‘lost’ to follow-up were excluded from the comparative analysis to allow for valid assessment across the two time periods.This is the second paper in the ROSIE Findings series and it provides a snapshot of the outcomes for people in the detoxification modality one year after treatment intake

Analysis of parameters of CMEs available in near real-time for operational space weather forecasting

Forecasts of geomagnetic activity are vital for helping to protect vulnerable technological infrastructure. However, we have relatively little data with which to make a decision about the level of expected activity. Whilst advances in modelling techniques (for example, the WSA-ENLIL model) and increases in data availability are helping, there is still a knowledge gap and forecasts still depend heavily on the judgement of the forecaster. The aim of this work is to help forecasters put coronal mass ejections (CMEs) into context, based on past events, in a straightforward manner. We have analysed CMEs during 12 years from Jan 1998 to Dec 2009, focusing on the data available at the time for forecasting. CMEs which were identified as having a potential to impact the Earth are then assessed and correlated with any resulting geomagnetic activity. Here we present statistics of Earth-directed CMEs and their likelihood to cause geomagnetic storms based on near-real time data. We review parameters including CME velocity, source location and associated flares and filament eruptions, and compare our results with other related studies

Extremes in worldwide geomagnetic activity

Geomagnetic storms pose a hazard to many modern technologies. Therefore understanding how severe such storms could be is important to a wide range of space weather data and forecast end-users. Extreme value statistical (EVS) methods are therefore applied to a global set of geomagnetic observatory data to determine the one in 100 and one in 200 year extreme values in the north, east and horizontal field strengths and their time rates-of-change. We use one-minute digital data from geographically widely distributed observatories with typically a few decades of digital operations. Individual generalised Pareto distribution functions are fitted to the tail of each observatory data distribution, above some threshold marking the onset of extreme activity for that location. We discuss the return levels, for the one in 100 and one in 200 year events, with respect to the geographical distribution of the observatories, the proximity to auroral and equatorial electrojets and compare results with a separate EVS study of European-only magnetic observatory dat

Polar geomagnetism

The availability of high-quality data during the past decade has allowed the development of geomagnetic field models which reproduce well the observed field at low to mid latitudes. However, the complexity of un-modelled processes and interactions in the polar ionosphere and magnetosphere causes significant residuals between data and models at high latitudes. Signatures of high latitude currents are clearly visible in the residuals for several recent models in both amplitude and direction, and so are not easily interpretable as field-aligned currents. Motivated by this we identify new techniques to allow more, and better quality, data to be selected for use in field modelling at high latitudes. We also look to include more vector data to improve data uniformity and distribution whilst still avoiding the un-modelled sources of the field, in particular within the auroral oval. We investigate both the use of additional indices in the selection process and a method of locating the highly variable external currents to identify the region where vector data are not selected. By introducing additional criteria we extended the local-time window allowing data density to have greater uniformity in time. We also include vector data at higher latitudes, only using scalar data where we believe external field sources are introducing noise to the data. When using our data selection criteria in the generation of a relatively simply parameterised geomagnetic model we get results that are close to more complex models. For example, we are able to reproduce features of the field seen in CHAOS-4, MF7 and EMAG3, despite only using CHAMP data for a single year. This makes us optimistic for future developments using longer time series

The development of contour processing: evidence from physiology and psychophysics

Object perception and pattern vision depend fundamentally upon the extraction of contours from the visual environment. In adulthood, contour or edge-level processing is supported by the Gestalt heuristics of proximity, collinearity, and closure. Less is known, however, about the developmental trajectory of contour detection and contour integration. Within the physiology of the visual system, long-range horizontal connections in V1 and V2 are the likely candidates for implementing these heuristics. While post-mortem anatomical studies of human infants suggest that horizontal interconnections reach maturity by the second year of life, psychophysical research with infants and children suggests a considerably more protracted development. In the present review, data from infancy to adulthood will be discussed in order to track the development of contour detection and integration. The goal of this review is thus to integrate the development of contour detection and integration with research regarding the development of underlying neural circuitry. We conclude that the ontogeny of this system is best characterized as a developmentally extended period of associative acquisition whereby horizontal connectivity becomes functional over longer and longer distances, thus becoming able to effectively integrate over greater spans of visual space

Evaluating the use of geomagnetic indices for identifying potential damage to power grids

Extreme geomagnetic storms have the potential to have a damaging impact on power infrastructure, through the currents they induce in the ground, termed geomagnetically induced currents (GICs). Such events are often classified and forecast in terms of the Kp index, with a Kp=9o event described as a G5 storm on the NOAA Space Weather Scale for geomagnetic activity. However, this global average, mid-latitude, 3-hour index is unlikely to be the most useful indicator of the short time-scale variations in magnetic field that are of most concern to power transmission operators. For example, depending on latitude an observatory K index of nine can represent a magnetic variation from tens to a few thousand nT. We therefore investigate the relation between GICs, both measured and modelled, to a range of geomagnetic indices. We use a range of validation techniques to evaluate how well these indices perform at identifying periods of large GICs in the UK, focusing in particular on geomagnetic storms. We also extend the study to look at possibilities for a new local index, based directly on the rate-of-change of the magnetic field, as well as forecasts of indices