Step 5: Collect and Evaluate Climate Model Data
For the analysis of temperature and rainfall ‘change factors’ are needed – the estimated change in the climate between a baseline period and future periods. These change factors are needed for average annual daily maximum temperature, average annual rainfall and for each month to calculate the number of months with <100 mm. These data are needed for all the emissions scenarios (RCPs) to illustrate the risk under a low emissions scenario compared to higher emissions scenarios to show the benefit of mitigation.
Guadalcanal is fairly small, so a single change factor for the whole island is enough. There is no high-resolution downscaling available to use for Solomon Islands, so this assessment has just used the available set of CMIP5 global climate models as input (Australian Bureau of Meteorology and CSIRO 2014).
Based on these data, the ranges of change meet all these requirements. Data from Australian Bureau of Meteorology and CSIRO (2014) use a group of CMIP5 global climate models that have been evaluated and use only the acceptable models – three unsuitable models were rejected (Grose et al. 2014).
Data from Australian Bureau of Meteorology and CSIRO (2014) presents ranges of projected change that are plausible, and values are available for all the RCPs for various time periods. The ranges of projected change are noted in Figures 4 and 5. The lower limits (cold) are not a problem in the Solomon Islands and are very unlikely to be a problem in future, so the focus is on the upper (warm) limit.
Australian Bureau of Meteorology and CSIRO (2014). Climate Variability, Extremes and Change in the Western Tropical Pacific: New Science and Updated Country Reports. Pacific-Australia Climate Change Science and Adaptation Planning Program Technical Report. Australian Bureau of Meteorology and Commonwealth Scientific and Industrial Research Organisation (CSIRO), Melbourne, Australia
Grose, M.R. and co-authors (2014). Assessment of the CMIP5 global climate model simulations of the western tropical Pacific climate system and comparison to CMIP3. International Journal of Climatology 34: 3382–3399.