Nature - autonomous learning

190 the dis/unity of geographyDrawing upon SSK arguments, Demeritt, in one of his published essays,engages in an auto-critique. He reflects upon his own ‘scientific research’into the climatic impact of stratospheric volcanic aerosols in north-easternUSA – research conducted in the early 1990s prior to his engagement withthe SSK literature. In this research, Demeritt sought to identify possiblecausal links between volcanic eruptions during the nineteenth and twentiethcenturies and climatic variance in the New England states. As part ofthis he used long-run temperature data transcribed at various weatherstations and searched for any volcanic signal with the ‘noise’. Reasonableas this correlation exercise may seem, it presumes that the temperature datais a reliable account of real temperature changes over time. But, as Demerittnotes, this cannot be proven: the contingencies of where, when, and howcarefully temperature readings were taken in previous decades is unknown.Demeritt simply had to assume that the temperature data were reliable. Ineffect, the data was a ‘black box’: its veracity could never be demonstrated.And even if Demeritt knew how rigorously taken temperature readings wereup to two centuries ago, how, he asks, would we know what level of rigouris acceptable? Are ten temperature readings per day per weather stationenough? How many weather stations are needed to give a true depictionof the climatic conditions of the north-eastern seaboard? The answers tothese questions, Demeritt, argues, are not dictated to us by the naturalenvironment.They are a matter of judgement.And herein lies the problem:if the temperature data that Demeritt used are the only direct evidence wehave of ‘real temperature’ then we can never know whether the data reflectsreality or reality contradicts the data. Since we cannot go back in time andcheck, we left in a position of having to take this data at face value as if itcorresponds to past climate.Demeritt’s preoccupation with the quality and quantity of data used inhis research speaks to a wider issue in physical geography (and indeed allfields of research). Physical geographers routinely use data-sets created byother researchers and organisations and take it on trust that these data setspossess a fair degree of truth-value. Equally, these geographers generatetheir own original data. In light of Demeritt’s analysis, one could raisequestions about how these geographers know when an ‘acceptable’ quantityand quality of data has been gathered about any given environmentalphenomena. More generally, the insights of SSK would lead us to examineeach and every stage of a physical geographer’s research – from the theoriesand hypotheses used to the equipment utilised to the way data is analysed.