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The present study analyses meridional atmospheric heat transport, due to transient eddies, in the European Centre for Medium-Range Weather Forecasts ERA-Interim reanalysis data. Probability density functions of the transport highlight the dominant role played by extreme events. In both hemispheres, events in the top 5 percentiles typically account for over half of the net poleward transport. As a result of this sensitivity to extremes, a large fraction of the heat transport by transient eddies, at a given location and season, is realised through randomly spaced bursts (a few per season), rather than through a continuum of events. Abstract Fast growing atmospheric modes are associated with a large heat transport, suggesting a link between these bursts and growing baroclinic systems (defined here as motions in the 2.5-6 day band). However, wavelet power spectra of the transport extremes suggest that they are driven by very precise phase and coherence relationships, between meridional velocity and moist static energy anomalies, acting over a broad range of frequencies (2-32 days). Motions with periods beyond 6 days play a key role in this framework. Moreover, these longer periods are found to be mainly driven by planetary-scale motions. Notwithstanding this, the heat transport bursts can be matched to specific synoptic-scale patterns. The bursts are therefore interpreted as the signatures of travelling synoptic systems superimposed on larger scale motions. The dominant role of extreme events can be reproduced in highly idealised simulations. Both a statistical model, where atmospheric motions are assumed to be linear superpositions of sinusoidal curves, and a two-layer model, representing heat transport as a quantised process effected by point vorticity anomalies, are successful in simulating the transport bursts. The fact that two very different idealised models both reproduce the transport's sporadic nature suggests that this must be an intrinsic property of waves in the atmosphere.

This study examined the association between serial killer typologies and previously proposed etiological factors within serial killer case histories. Stratified sampling based on race and gender was used to identify thirty-six serial killers for this study. The percentage of serial killers within each race and gender category included in the study was taken from current serial killer demographic statistics between 1950 and 2010. Detailed data was gathered about each case, including past experiences and details of their crimes using publicly available primary and secondary source material. Etiological factors identified for this study include military experience, alcohol use, drug use, whether or not the subject was bullied as a child or sexually abused, whether they displayed assaultive behavior as an adolescent, whether they were physically abused by their maternal figure, and whether they had engaged in animal torture or engaged in fire setting in childhood or adolescence. The presence of these factors was coded dichotomously (present = 1; not present = 0) for each case history. Cases were then divided by inclusion in two typologies: the FBI’s organized/disorganized typology and Holmes, Holmes, and DeBurger’s intrinsic motivation typology. The etiological factors were examined for interrelatedness and prevalence in the designated serial killer typologies. Results of crosstabulations and chi-squared analysis showed that military experience was significantly associated with the organized/disorganized typology (p