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For volcanoes, as for other natural hazards, the frequency of large events diminishes with their magnitude, as captured by the magnitude–frequency relationship. Assessing this relationship is valuable both for the insights it provides about volcanism, and for the practical challenge of risk management. We derive a global magnitude–frequency relationship for explosive volcanic eruptions of at least 300 Mt of erupted mass (or M4.5). Our approach is essentially empirical, based on the eruptions recorded in the LaMEVE database. It differs from previous approaches mainly in our conservative treatment of magnitude-rounding and under-recording. Our estimate for the return period of ‘super-eruptions’ ( 1000 Gt , or M8) is 17 ka (95% CI: 5.2 ka , 48 ka ), which is substantially shorter than previous estimates, indicating that volcanoes pose a larger risk to human civilisation than previously thought. [ABSTRACT FROM AUTHOR]

A simple neo-classical real business cycle model is presented. The model can produce multiple equilibria as a result of the interaction between the production and investment processes. Changes in the supply of funds and in capital stock yield persistence. Results demonstrate that the problem of costly state verification makes it easier to generate multiple equilibria. Findings also suggest the potential relevance of other sources of heterogeneity or non-linearity.

Sensitivity Analysis (SA) investigates how the variation in the output of a numerical model can be attributed to variations of its input factors. SA is increasingly being used in environmental modelling for a variety of purposes, including uncertainty assessment, model calibration and diagnostic evaluation, dominant control analysis and robust decision-making. In this paper we review the SA literature with the goal of providing: (i) a comprehensive view of SA approaches also in relation to other methodologies for model identification and application; (ii) a systematic classification of the most commonly used SA methods; (iii) practical guidelines for the application of SA. The paper aims at delivering an introduction to SA for non-specialist readers, as well as practical advice with best practice examples from the literature; and at stimulating the discussion within the community of SA developers and users regarding the setting of good practices and on defining priorities for future research. [ABSTRACT FROM AUTHOR]