The Anthropocene: an Australasian perspective and survey.

In 2000, Crutzen and Stoermer suggested that the Holocene (the geological period of time since 11,700 years ago: Walker et al., 2009) had finished and that humanity had now entered the “Anthropocene”. As summarised by Steffen et al. (2011) and Wolfe et al. (2013), these scientists were referring to the Anthropocene as the interval of demonstrable human alteration of global biogeochemical cycles, beginning subtly in the late 18th Century following James Watt’s invention of the coal-fired steam engine, and accelerating markedly in the mid-20th Century (called “The Great Acceleration”)

A review of late Quaternary silicic and some other tephra formations from New Zealand: their stratigraphy, nomenclature, distribution, volume, and age.

The stratigraphic relationships and distribution of 36 named late Quaternary (≤c. 50 000 yr B P.) silicic tephra formations, erupted from 4 volcanic centres—Okataina, Taupo, Maroa, and Tuhua (Mayor Island)—are presented. The stratigraphy and status of several other named late Quaternary tephras are also discussed. This compilation brings together all the data, currently scattered through many publications, to make tephrostratigraphy more accessible and more easily used. The nomenclature of tephra formations is discussed and some rationalisations are suggested. The term “tephrology” is suggested as an appropriate title for the field of tephra studies. The deletion of grain-size (ash, lapi1li), shape (breccia), and lithologic (pumice) terms from all formation names is recommended, as is standardisation on a “Tephra Formation” formal Several tephra layers not previously formally named, or without designated type sections, are defined. The dominant ferromagnesian mineral assemblage of each tephra formation has been compiled as an aid to tephra identification. All available radiocarbon ages (384) on each tephra formation are presented, and each age is assessed for reliability in dating the eruption of that tephra. The standard-deviation weighted mean age of the reliable ages has been determined as the best current estimate of the age of each tephra. At least 10 tephra formations have no reliable ages, and efforts should be made to date thes

Determination of species

There are no author-identified significant results in this report

On the evolution of snow roughness during snow fall

The deposition and attachment mechanism of settling snow crystals during snowfall dictates the very initial structure of ice within a natural snowpack. In this letter we apply ballistic deposition as a simple model to study the structural evolution of the growing surface of a snowpack during its formation. The roughness of the snow surface is predicted from the behaviour of the time dependent height correlation function. The predictions are verified by simple measurements of the growing snow surface based on digital photography during snowfall. The measurements are in agreement with the theoretical predictions within the limitations of the model which are discussed. The application of ballistic deposition type growth models illuminates structural aspects of snow from the perspective of formation which has been ignored so far. Implications of this type of growth on the aerodynamic roughness length, density, and the density correlation function of new snow are discusse

Dynamic trust models for ubiquitous computing environments

A significant characteristic of ubiquitous computing is the need for interactions of highly mobile entities to be secure: secure both for the entity and the environment in which the entity operates. Moreover, ubiquitous computing is also characterised by partial views over the state of the global environment, implying that we cannot guarantee that an environment can always verify the properties of the mobile entity that it has just received. Secure in this context encompasses both the need for cryptographic security and the need for trust, on the part of both parties, that the interaction is functioning as expected. In this paper we make a broad assumption that trust and cryptographic security can be considered as orthogonal concerns (i.e. an entity might encrypt a deliberately incorrect answer to a legitimate request). We assume the existence of reliable encryption techniques and focus on the characteristics of a model that supports the management of the trust relationships between two entities during an interaction in a ubiquitous environment