The Impact of Climate Change on Historic Interiors
It is widely understood that the environment is critical for the preservation of historic collections and interiors, if the environment is unsuitable it can create an increased risk of damage. In historic houses collections are usually on open display, and the room environment often has little control thus it is vulnerable to changes in the outdoor environment. The future outdoor environment is projected to change so the aim of this work has been to develop a widely applicable model to investigate the potential impact of climate change on historic interiors. A simple transfer function has been used to predict indoor temperature and relative humidity. The method is widely applicable and easily transferable between unheated buildings. It has been shown that it is important to assess each location and room on an individual basis. The method has been coupled with future climate output, from both the UKCP09 weather generator and the Hadley model, where data has been downscaled. The high resolution climate output allows for projections of future indoor environment. Future temperature is projected to increase in unheated historic houses around the UK and across Europe, although less than outdoors. Annual average relative humidity is largely unchanged in the future. Damage functions are used to determine the impact of the future indoor environment on materials. Typically temperature driven damage such as chemical degradation of paper and silk and insect pest activity increase in the future, whereas damage driven by relative humidity, such as salt transitions, depends upon the location assessed. In general risk of mould growth increases, and dimensional changes to wood decrease. The significance of future changes is an important consideration, requiring some further work. Annual averages are shown to hide seasonal changes, thus it is important to assess these, which can impact upon management strategies. At Knole it is projected that the summer humidity will decrease and the winter humidity increase slightly, which raises the risk of mould growth. The application of conservation heating has been shown to be less effective in future, but is still an effective strategy, although dehumidification may become more appropriate in some locations. The future energy use of conservation heating has a negligible change. There are a number of inherent uncertainties associated with the models used here. Specifically with climate modelling, future emissions are unknown and the physical processes of the climate are not fully understood. There is a statistical error associated with the transfer function, and the damage functions also have a number of related uncertainties. It is important to consider these when assessing future indoor projections. The results allow for long term planning by collection managers, to prepare for the impact of climate change, thus preserving heritage for future generations.
Networked Digital Library of Theses and Dissertations