2008 Seasonal Prediction for Canada Kerry Anderson Richard Carr Peter Englefield

Methodology 1. Calculate spring start-up conditions based on fall drought code (DC) values and over-winter precipitation amounts, 2. Calculate average daily weather for weather stations across country, 3. Incorporate Environment Canada’s seasonal predictions, 4. Determine the fire severity based on the ratio of forecasted over average seasonal severity rating (SSR).

Changes from Last Year 1. Inclusion of 4 model, 10 member ensemble predictions from Environment Canada, 2. Estimate confidence range based on ensemble spread, 3. Move towards monthly predictions, 4. Evaluation of past forecasts.

Ensemble Forecasts Recently, the Canadian Meteorological Centre (CMC) of Environment Canada has begun providing temperature and precipitation probabilistic forecasts based on an ensemble of ten integrations of four independent models: 1. climate ver. of the Global Environmental Multiscale model (GEM-CLIM), 2. 2nd gen. of the Atmospheric General Circulation Model (AGCM2), 3. 3rd gen. of the Atmospheric General Circulation Model (AGCM3), 4. Spectral aux éléments finis (SEF). Forecasts are provided for the next four months.

Ensemble Forecasts The ensemble approach provides a measure of confidence indicated by the spread of the ensemble members. The extended forecast continues to use the single, deterministic forecast

2007 Seasonal Prediction

2007 Prediction Last year’s prediction showed below-average conditions throughout much of Canada. Only Vancouver Island, central Saskatchewan and northern Manitoba show above- average severity.

2007 Prediction As it turned out, 2007 was a quiet fire season with fire activity limited to Quebec, Southeastern BC, and the northern boreal plains.

2008 Seasonal Prediction

Spring Start-up Conditions The Canadian Forest Fire Weather Index (FWI) System allows for the carry-over of fall conditions to the spring. This is handled by the Drought Code (DC) (similar to the 1000 hour moisture code). All other moisture codes in the FWI system are reset.

Spring Start-up Conditions Fall DC values show high (dry) conditions throughout much of Western Canada and the Territories with the highest values in Northeastern Alberta and the Yukon.

Spring Start-up Conditions Most of the winter precipitation came to western BC, the parts of the Yukon and Eastern Canada. The southern Prairies and western Ontario saw below-average amounts of snow over the winter.

Spring Start-up Conditions Eastern Canada, the northern Prairies and western BC near total recharge of deep fuel moistures. Southeastern BC and the southern Prairies, parts of the Yukon and the Mackenzie basin show high spring DC values.

Seasonal Forecasts Spring temperature anomalies are low for western Canada and high for eastern Canada. Precipitation anomalies are high for nearly all of Canada except for southern Alberta, BC and the far north. April-May-June

Seasonal Forecasts Early summer sees above normal temperatures throughout most of Canada with the exception of BC. Above normal precipitation predicted for Alberta, Saskatchewan and Manitoba, below in southern BC and western Ontario May-June-July

Seasonal Forecasts Summer temperature anomalies are high for western and northern Canada. Below-normal precipitation is predicted for central BC and Hudson’s Bay, while above-normal precipitation is predicted for the central prairies, the western territories and much of eastern Canada June-July-August

April 2008 Low conditions in the Prairies and eastern Canada. Above average conditions in the northwest though confidence is low for Mackenzie basin. Prediction (predicted values normalized against average weather) Confidence (standard deviation normalized against average weather)

May 2008 Average conditions throughout most of Canada except for the Mackenzie basin, northern Quebec and Labrador (above), and Churchill (below). Prediction (predicted values normalized against average weather) Confidence (standard deviation normalized against average weather)

June 2008 With the exception of northern BC and the Maritimes, June sees an increase in fire weather conditions in much of Canada. Prediction (predicted values normalized against average weather) Confidence (standard deviation normalized against average weather)

July 2008 July sees an significant increase in fire weather conditions in nearly all of Canada. Low confidence in predictions for northern and western Canada (the extreme areas). Prediction (predicted values normalized against average weather) Confidence (standard deviation normalized against average weather)

July, August, September 2008 Predictions (based on deterministic) show increased fire weather severity in BC, Manitoba and western Ontario. Confidence in these extended forecasts are low. Predictions (predicted values normalized against average weather)

May-Aug 2008 The 2008 fire season is above-average for BC through Ontario (except for central Prairies). Confidence is highest in BC and eastern Canada. Prediction (predicted values normalized against average weather) Confidence (standard deviation normalized against average weather)

The End