DOI: 10.5281/zenodo.15091493
title: Future-Shifted Weather Files for Canada using Climate Projections from CMIP6

description: Background

This dataset includes future-shifted versions of the Canadian Weather Year for Energy Calculation 2020 weather files (CWEC2020; [1], [2]) produced using future climate projections from CMIP6 climate models. CWEC2020 weather files in Canada offer a summary of typical climatic conditions at specific locations to analyze and simulate building energy use. These files contain hourly weather station-based observations encompassing a single year that is meant to be representative of average conditions from the recent past, defined as a Typical Meteorological Year. Ongoing climate change means the information summarized in these weather files may not reflect present day conditions and is expected to become increasingly unrepresentative over typical building lifespans. Future-shifted files can be used with energy modelling software to compare building energy use between past and future conditions.

These future-shifted files are produced using a “morphing” procedure that adjusts the mean and variance of the hourly series [3] with morphing factors calculated from CMIP6 climate model projections for five future periods (2040s to 2080s). Projected changes used to calculate morphing factors are taken from 18 CMIP6 global climate models following low, medium and high future emissions pathways (SSP1 2.6, SSP2 4.5, SSP5 8.5). Existing hourly series in the weather files are modified using additive or multiplicative morphing factors that are derived from the climate projections. 

Dataset Format

This dataset consists of 15 future-shifted weather files at each of the 564 CWEC2020 locations in Canada. Future-shifted files employ the same EPW file structure formatting as the current CWEC2020 files. Within each future-shifted file, the hourly time series of dry bulb and dew point temperature, relative humidity, and surface pressure are adjusted using the morphing method to incorporate future climate change. The hourly time series for all other variables remain unchanged. 

The uploaded files are organized into separate zip files for each Canadian province or territory. Each zip file contains separate directories for all CWEC2020 locations within the province or territory. These location directories each contain the 15 future-shifted weather files generated using the current CWEC2020 file at that site.

The future-shifted files are also available in csv format with the header information removed. The csv files for all provinces and locations are contained within the CSV_Future_Weather_Files.zip file. 

Data Portal

All future-shifted CWEC2020 files are also accessible via a purpose-built data portal with search options to select files from specific locations: https://www.pacificclimate.org/data/weather-files

References

1) Engineering Climate Services Unit. CWEEDS/CWEC/TDY Files - 2020 Release. Technical report, Toronto, ON, Canada, 2020.

2) Robert Morris. Final Report - Updating CWEEDS Weather Files. Technical Report EC3000607888, Environment and Climate Change Canada, Toronto, ON, Canada, 2016.

3) S.E. Belcher, J.N. Hacker, and D.S. Powell. Constructing design weather data for future climates. Building Services Engineering Research and Technology, 26(1):49–61, February 2005.