Nugget variance - Positive intercept on the ordinate of the semi-variogram indicating the unexplained variance.
Numerical models - Models which use a conceptual model to define links between fundamental physical, chemical and occasionally biological principles, which are then represented mathematically in computer code.
Open coding - Also called ‘free coding’. Refers to the first stage of coding when the text is read through thoroughly and anything of interest is coded as the researcher goes along; used to ‘open up’ the text.
Ordinal data - A measurement level indicating the relative significance of a feature, but not its precise dimensions.
Palaeoclimatic reconstruction - The reconstruction of environmental conditions over timescales from hundreds to millions of years based upon direct and proxy evidence.
Palaeoclimatic signal and noise -These arise in interpreting proxy environmental records where the effects of climate (the signal) have to be separated from the effects of all other non-climatic influences (the noise).
Parameterization - Use of a numerical quantity in a model to represent the effect of a more complex process or property, or set of process interactions.
Partial plot - A graphical plot between two variables, after accounting for the modelled effects of other possible explanatory variables.
Participatory research - Involves working in a collaborative fashion to develop alternative ways to generate data based on joint agenda setting, analysis and control of outcomes.
Passive sensors - Receive electromagnetic radiation from an external source (primarily reflected sunlight).
Positionality - Recognizing and trying to understand the implications of the social position of the researcher with respect to the subjects, particularly with regard to power relations or cultural differences that may influence the process of the research and its interpretation. For example, how we are positioned in relation to various contexts of power (including gender, class, ‘race’, sexuality, job status, etc.) affects the way we understand the world. Likewise, the information given by informants to a researcher may depend on how the researcher is viewed in that particular context (threatening, insignificant, powerful).