Applying climate data in resource management requires matching the spatial scale of the climate and resource databases. In this project we developed a methodology to generate scale-free climate data through the combination of interpolation techniques and elevation adjustments. The method was applied to monthly temperature and precipitation normals for 1961-90 for British Columbia, Yukon Territories, the Alaska Panhandle, and parts of Alberta and United States produced with the Parameter-elevation Regressions on Independent Slopes Model (PRISM). Equations were developed to calculate biologically and hydrologically relevant climate variables (including degree-days, number of frost-free days, frost-free period and snowfall) from monthly temperature and precipitation data. Estimates of climate variables were validated using an independent data set from weather stations that were not included in the development of the model. Weather station records generally agreed well with estimated climate variables and showed significant improvements over original PRISM climate data. A stand-alone MS Windows® application (ClimateBC) was developed to perform all calculations and to integrate predictions of future climate from various global circulation models. Examples of applications of the spatially distributed, scale-free data are presented. Data produced by ClimateBC was used to determine climatic moisture deficits on an elevation transect on Vancouver Island. Climate data at 400 m grid spacing were overlain on subzone variant maps of the Biogeoclimatic Ecosystem Classification system to provide descriptions of variant climates. This was repeated for future possible climates and assessments made of changes in climate of selected ecosystems and potential responses of the vegetation. The influence of climate change on snow accumulation and melt at a high-elevation forest site was evaluated. Data and programs are available through web sites.
complied by David L. Spittlehouse.
Spittlehouse, David L.. 2006. Spatial climate data and assessment of climate change impacts on forest ecosystems. Forest Investment Account (FIA) - Forest Science Program. Forest Investment Account Report