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Nuclear war analysts often compared nuclear detonations to volcanic eruptions. The connection between volcanic eruptions and climatic changes, suggested long ago by Benjamin Franklin and others, received serious interest from researchers only in the early twentieth century. Today, however, a direct comparison between volcanic eruptions and nuclear war is deemed inappropriate owing to the different absorption properties of sulfuric acid and silica dust than dark smoke. Furthermore, the distributions of particle sizes are different, and warfare would give rise to fine particles from a variety of sources rather than a single location. This chapter examines scientific disciplines with less obvious connections to nuclear war, including volcanic eruptions, ozone depletion, planetary studies, dinosaur extinction, and the asteroid impact hypothesis.

What kind of place was Bronte? Nobody knew anything about it. The community was located on the remote, western side of Mount Etna: it was a beautiful spot with commercial potential but it was also isolated, dangerous and unfriendly. The town was filled with poor peasants who were oppressed by a few rich landowners; the whole area was threatened by regular volcanic eruptions and outbreaks of disease (notably, malaria); and the Duchy headquarters at Maniace, where the British planned to live, had been destroyed by an earthquake in 1693 and never rebuilt again. The community also enjoyed a dubious reputation for violence and savagery.

A first-hand account of Vesuvius' eruption in 79 CE has survived in the form of two letters by Pliny the Younger, who witnessed the event from his uncle's villa at Misenum. Pliny's physical presence on the Bay of Naples in late August of 79 CE has lent his letters a canonical authority, and they have functioned in the modern era as a sort of window through which to witness the eruption. This chapter proposes that, rather than being the last word in describing the eruption, Pliny stands as the first in a long and distinguished tradition of re-creating it in the service of formal history — a tradition that 1,700 years later inspired one of the quintessential history painters of the era, the Swiss Angelica Kauffmann, to compose the Pliny the Younger and his Mother at Misenum, now at Princeton. It is argued that the letters and painting in question are unified by more than the standard relationship between an ancient text and a modern image. Both Pliny and Kauffmann had a vested interest in making history, which was something of a leap for this particular author and artist.

Classical archaeology is something generically different from archaeology. It is almost as if the resemblances of names, like that between history and natural history, resulted from the survival of an obsolete usage. It is time that this was changed. There is first the exceptionally thorough coverage through field-work of certain parts of the ancient Mediterranean: how many areas are there, up to sixty miles by thirty, which have more than 650 established ancient sites, as Messenia has? Secondly, there is the possibility of recognising the handiwork of a single artist in a series of works: by this means, some precision can be given to the chronology of Greek pottery in the eighth century BC; and it is this, more surprisingly, which enables two crucial episodes 800 years earlier still, the burials in the shaft-graves at Mycenae and the volcanic eruption of Thera, to be shown to be contemporary.

Research on the nuclear winter phenomenon involved more than half a dozen scientific disciplines, from particle microphysics and atmospheric chemistry to ozone depletion, studies on the effects of nuclear weapons, fire and smoke research, volcanic eruptions, planetary studies, and even dinosaur extinction. This chapter describes some relevant aspects of fields with obvious connections to nuclear war.

Earth’s crust is largely composed of oxides, so the biosphere we inhabit is dominated by interactions between oxides, water, and living things. Part Six of this book, on environmental geochemistry, focuses on these interactions and serves as a review of many of the chemical concepts that form the basis for the rest of the book. As such, the final two chapters frequently refer back to previous chapters for more in-depth discussions of specific chemical phenomena. In this chapter, however, we highlight how the diverse environments on the surface of Earth modify the structure, composition, and chemistry of oxide minerals by weathering phenomena. Conversely, in Chapter 18 we explore how oxide minerals and their weathering products modify the structure, composition, and chemistry of the environments they inhabit. These environmental interactions are influenced by life, and are critical to the health and well-being of all living things. Minerals have a natural life cycle on the surface of Earth. Most oxides emerge from Earth’s interior in the form of igneous rocks that form and are stable at the high temperatures and pressures of subsurface environments (see Chapter 18). These minerals usually do not represent phases that are thermodynamically stable in ambient-temperature water. As a result, any pristine rocks exposed to air and water are subject to the physical and chemical degradation processes we call weathering (Fig. 17.1 and Plate 20). Weathering processes facilitated by water convert anhydrous oxides formed at high temperatures into hydrous oxides, oxyhydroxides, hydroxides, and dissolved by-products. It has been estimated that volcanic rocks represent only 8% of the rocky outcrops on Earth’s surface whereas 26% are more coarsely grained plutonic rocks of igneous origin. The remaining 66% of rocky outcrops represent the decomposition products of these igneous parents, including sandstone (16%), claybased rocks such as shale (33%), and simple ionic salts such as limestone (16%) and evaporates (1.3%). The focus of this chapter is on the physical and chemical processes that form and affect these decomposition products under ambient-temperature conditions.

Different types of global catastrophic risks (GCRs) are studied in various chapters of this book by direct analysis. In doing so, researchers benefit from a detailed understanding of the interplay of the underlying causal factors. However, the causal network is often excessively complex and difficult or impossible to disentangle. Here, we would like to consider limitations and theoretical constraints on the risk assessments which are provided by the general properties of the world in which we live, as well as its contingent history. There are only a few of these constraints, but they are important because they do not rely on making a lot of guesses about the details of future technological and social developments. The most important of these are observation selection effects. Physicists, astronomers, and biologists have been familiar with the observational selection effect for a long time, some aspects of them (e.g., Malmquist bias in astronomy or Signor-Lipps effect in paleontology) being the subject of detailed mathematical modelling. In particular, cosmology is fundamentally incomplete without taking into account the necessary ‘anthropic bias’: the conditions we observe in fundamental physics, as well as in the universe at large, seem atypical when judged against what one would expect as ‘natural’ according to our best theories, and require an explanation compatible with our existence as intelligent observers at this particular epoch in the history of the universe. In contrast, the observation selection effects are still often overlooked in philosophy and epistemology, and practically completely ignored in risk analysis, since they usually do not apply to conventional categories of risk (such as those used in insurance modelling). Recently, Bostrom (2002a) laid foundations for a detailed theory of observation selection effects, which has applications for both philosophy and several scientific areas including cosmology, evolution theory, thermodynamics, traffic analysis, game theory problems involving imperfect recall, astrobiology, and quantum physics. The theory of observation selection effects can tell us what we should expect to observe, given some hypothesis about the distribution of observers in the world. By comparing such predictions to our actual observations, we get probabilistic evidence for or against various hypotheses.

In coastal dune systems, plant communities are fundamentally the product of interaction between disturbance of the substrate, impact of high wind velocities, salt spray episodes, sand accretion levels and other factors of the environmental complex. Burial by sand is probably the most important physical stress that alters species diversity by eliminating disturbance-prone species (Maun 1998). There is a close correlation between sand movement and species composition, coverage and density (Moreno-Casasola 1986; Perumal 1994; Martínez et al. 2001). Sand accretion kills intolerant species, reduces the relative abundance of less tolerant species and increases the abundance of tolerant species. It filters out species as the level of burial starts to exceed their levels of tolerance. For example, lichens and mosses are the first to be eliminated, then the annuals and biennials and finally the herbaceous and woody perennials. Again within each life form and genus there are significant differences in survivability. Burial imposes a strong stress on production by altering normal growth conditions and exposing plants to extreme physiological limits of tolerance. Do plant communities occurring in different locations within a dune system correspond to the amount of sand deposition? Several studies (Birse et al. 1957; Moreno- Casasola 1986; Perumal 1994) show that the species composition and their distribution are strongly related to the long-term average sand deposition. The evolution of a plant community in coastal foredunes requires frequent and persistent predictable burial events specific to a particular coast. In a large majority of sea coasts burial occurrences are of relatively low magnitude and species occupying the coasts are well adapted to withstand the stress imposed by burial. This recurring event within the generation times of plant species allows them to acquire genes of resistance over time and evolution of adaptations to live in this habitat. A prerequisite to survive in this habitat happens to be the ability to withstand partial inundation by sand. To survive the dynamic substrate movement a plant species must be a perennial, be able to withstand burial, endure xerophytic environment, spread radially and vertically, and adapt to exposure on deflation and coverage on burial (Cowles 1899).