Learn about Climate Change: Research Historical Data and Future Climate Modeling

 

The information included herewith is the basis of climate change adaptation planning. It is important to understand the basic historical trends and future climate projections to help inform future discussions. There will be many questions posed around the data and use of models. The information below provides a summary of the key sources for information, their relevance and limitations, as well as advice about how to better understand the meaning behind the models.

 

Information Sources: Pacific Climate Impacts Consortium Modeling

 

CBT's Partner, The Pacific Climate Impacts Consortium (PCIC) has created a regional overview of the Columbia Basin in terms of historical and predicted future climate trends. This information is neatly summarized on their website. Maps and brief interpretations are provided.

PCIC Climate Change Analysis - Columbia Basin 2006 pdf (1.8M) This is the initial document from PCIC in 2006. It is an in-depth study into climate change in the Columbia Basin and the basis for Communities Adapting to Climate Change.

Analytical Summary -draft Kimberley and Elkford 2008 pdf (2.9M) This summary report was the foundation and main scientific piece for Kimberley and Elford.

Climate Maps from the Columbia Basin pdf (6.2M) All maps from the 2008 report from the Columbia Basin. Useful for people looking for more specific information, details such as seasonal differences. You can save the maps of interest as images and use them in presentations or to make summary documents for communicating.

Starting the Dialogue pdf (1.1M)  "Starting the Dialogue" is a shortened version of the larger report from PCIC and is an excellent document for understanding and communicating climate change impacts and adaptation in the Canadian Columbia Basin.

 

How Results were used in Kimberley and Elkford

  • Future projections and historic trends became the foundation for the climate change adaptation planning work in each community, and it provided credibility to the work. Historic data and trend analyses are particularly important since they not only capture the extremes but also highlight vulnerabilities in a community.
  • The information provided a foundation for discussing potential impacts.
  • The material became a starting point for further research.

 

Relevance and Limitations

  • Projections for the future include estimates of uncertainty.
  • Future climatic changes and the impacts associated with those changes will vary drastically between different ecosystems across B.C.
  • Precipitation and temperature changes must be analyzed further to understand how these changes will impact other forces of disturbance (e.g., wildfire, flooding), the soils, flora and fauna, and the eventual impacts on our community infrastructure, economy, recreation, and general well-being.
  • The climatology data provided by PCIC is a good start to understanding potential climate change impacts, but, this data must be taken a step further to better understand human and ecosystem impacts.
  • Climate analysis and modeling is complex and subject to understanding some basic principles.
  • In Kimberley, local expectations around what science would tell them about climate impacts were significantly beyond what was feasible within the parameters of the project and the current science.

 

Understanding the Historical Climate Analysis

Reflections from Kimberley's Coordinator, Ingrid Liepa 2009

  • Historical climate analysis is based on a model called PRISM that uses monthly and annual temperature and precipitation data from stations around the Basin. It takes into account the elevation, orientation of terrain, proximity to the coast, moisture availability, a two-layer atmosphere (to handle inversions), and topography (valley, midslope, ridge) of the station where the data was collected, weighting and interpolating the data over a high resolution 4 km grid.
  • Seasonal and monthly variability resulting from El Nino/La Nina (ENSO) and the Pacific Decadal Oscillation (PDO) are also shown in the historical climate analysis. These results use gridded Environment Canada station data (CANGRID) because the PRISM historical data is available as a baseline period only and variability analysis requires time series. This analysis is at a 50 km resolution.
  • The period of 1961-1990 is used as the baseline for comparing historical climate with future projections, whereas the 1900-2004 period is used to show changes in temperature and precipitation over the last century. 1961-1990 is used because it is still fairly recent, i.e. older generations can recall the weather back in the 1970s, and more importantly because it captures roughly equal spans of a warm and cold PDO cycle.
  • As a general rule for Kimberley:
               El Nino means warmer, drier winters
               La Nina means colder, wetter winters
               A warm PDO phase means drier winters, wetter springs
               A cold PDO phase means wetter winters, drier springs
  • The ENSO and PDO cycles have different lengths, with ENSO in the 2-7 year range and PDO in the 20-30 year range. Laypersons are cautioned not to look at ENSO and PDO in a simple, additive manner, ie. what would happen if we were in a warm PDO with an El Nino event - and then adding together the relative changes to temperature and precipitation associated with each. Note: For more information on ENSO and PDO, a quick search online will provide abundant additional information.

Understanding the Basis for Future Climate Projections

Reflections from Kimberley's Coordinator, Ingrid Liepa 2009


Future climate projections were made available using Global Climate Models (GCM) and a Regional Climate Model (RCM). The GCM models have a "coarse" resolution, meaning that the data is based on ~350 km grid cells. The RCM brings it to a more detailed resolution of 45 km. That said, the "coarse" resolution GCM projection is based on running 30 different Global Climate Models and the RCM is only one model. The RCM projections tend to be warmer and wetter than the composite of 30 GCM projections, so the reader must be aware of that bias when looking at the RCM maps for the Basin. The RCM maps are best used for understanding relative changes to precipitation and temperature within the Basin as between different areas, whereas the coarse resolution GCM projections are considered to be more accurate in terms of projecting the range of plausible changes to temperature and precipitation in the future.

For considering future changes to local/regional climate in the 2050s, using the middle range of the 30 GCM projections (25th to 75th percentiles) provides a valuable range to work with in terms of upper and lower ends.  This can form the basis for asking useful "what if" questions around the upper and lower ends of temperature and precipitation projections.

 

For more images and maps, visit The Pacific Climate Impact Consortium.