The uncertainties in simulating the future hygro-thermal performance of an attic related to global climate models

Paper in proceeding, 2010

Climate changing has been a debated subject during the last few years. Several future climate predictions have been generated based on numerical modeling. There are differences between climate data sets depending on the driving global climate models, initial conditions, emission scenarios, regional climate models, etc. Each future climate is based on some assumptions and consequently has some uncertainties. These uncertainties are dragged to the building simulation results by using the climate data for assessing the future performance of buildings. In this paper the uncertainties connected to having different global climate models are studied. The analysis is given for the city of Stockholm in Sweden and for the period from 1961 to 2100. The indoor climate of a cold attic has been simulated for the climate conditions of four different global climate models. Temperature and relative humidity of the climate have been analyzed using the method of decomposition of variabilities. The method helps to compare different climate and simulation results in long time periods. The comparison guides to understand the importance and effectiveness of outdoor climate variability components on the indoor climate. Sensitivity of the simulation results to different global climate models is illustrated when the indoor response to the long term and short term changes of the outdoor climate is considered.