Thursday 24 May 2018

2018 Wind trajectories (May 24, 2018; Wk 03)

Background.  Agriculture and Agri-Food Canada (AAFC) and Environment and Climate Change Canada (ECCC) have been working together to study the potential of trajectories to deliver an early-warning system for the origin and destination of migratory invasive agricultural pests. 

We receive two types of model output from ECCC: reverse trajectories (RT) and forward trajectories (FT): 

(i) ‘Reverse trajectories’ (RT) refer to air currents that are tracked back in time from specified Canadian locations over a five-day period prior to their arrival date. 

(ii) ‘Forward trajectories’ (FT) have a similar purpose; however, the modelling process begins at sites in USA and Mexico. The model output predicts the pathway of a trajectory. Again, of interest are the winds that eventually end up passing over the Prairies. 


Current Data

Pacific Northwest (PNW) – The total number of RT’s from the Pacific Northwest of the United States, for the period between May 1 - 22, 2018, was n=67.  This was significantly less than in 2017 (n=226), as well as the long term average (n=166) (Fig. 1).


Figure 1. Daily total number of reverse trajectories originating over the Pacific Northwest of
the United States that have entered the prairies (May 1-22, 2018).


Weather forecasts (7 day):