Wind trajectories
Related to Diamondback Moth (DBM) and Aster Leafhopper Introductions
BACKGROUND: Potential wind events capable of carrying insect
pests from source areas in the USA can be identified by following trajectories
for air parcels through time. High altitude air masses, originating
from southern locations, frequently move northerly to Canadian destinations.
Insect pest species such as Diamondback moth and Aster leafhoppers,
traditionally unable to overwinter above the 49th parallel, can utilize these
air masses in the spring to move north from Mexico and the United States
(southern or Pacific northwest). Data acquired from Environment Canada is
compiled by Olfert et al. (AAFC-Saskatoon) to track and model high altitude air
masses in the spring with respect to potential introductions of insect pests
onto the Canadian prairies. Each week, backward and forward trajectories
are examined with respect to source and destination in the following manner. The
forward trajectories are prognostic (5 days into the future) based on forecast
wind fields while the backward trajectories are diagnostic and based on
analyzed wind fields (5 days previous).
FOR THE WEEK OF APRIL 3-7, 2015: Wind trajectory data processing by AAFC-Saskatoon Staff began in April. Reverse Trajectories track arriving air masses back to their point of origin while Forward Trajectories predict favourable winds expected to arrive across the Canadian Prairies for the week of April 3-7, 2015:
Reverse trajectories (RT)
Pacific
Northwest (PNW) – The number of reverse trajectories from Prairie locations
with links to the PNW continues to be relatively high. the following 25 locations had RT’s,
originating from the PNW, that crossed the prairies on April 1 and 2, 2015. Of
particular interest were the northern AB locations reported for April
7.
Reverse Trajectories Originating from PNW Arriving at Prairie Locations
|
Location ID
|
Arriving Date
(dd-m-year)
|
Latitude
|
Longitude
|
WANHAM_AB
|
07/04/2015
|
55.7
|
-118.4
|
VEGREVILLE_AB
|
07/04/2015
|
53.5
|
-112
|
SEDGEWICK_AB
|
07/04/2015
|
52.8
|
-111.7
|
RYCROFT_AB
|
07/04/2015
|
55.8
|
-118.7
|
REGINA_SK
|
07/04/2015
|
50.5
|
-104.5
|
PROVOST_AB
|
07/04/2015
|
52.4
|
-110.3
|
OLDS_AB
|
07/04/2015
|
51.8
|
-114.1
|
LETHBRIDGE_AB
|
07/04/2015
|
49.7
|
-112.8
|
KINDERSLEY_SK
|
07/04/2015
|
51.5
|
-109.1
|
GRENFELL_SK
|
07/04/2015
|
50.4
|
-102.9
|
GRANDE_PRAIRIE_AB
|
07/04/2015
|
55.2
|
-118.8
|
GAINSBOROUGH_SK
|
07/04/2015
|
49.2
|
-101.4
|
FORT_VERMILION_AB
|
07/04/2015
|
58.4
|
-116
|
BEISEKER_AB
|
07/04/2015
|
51.4
|
-113.5
|
ANDREW_AB
|
07/04/2015
|
53.9
|
-112.3
|
VEGREVILLE_AB
|
06/04/2015
|
53.5
|
-112
|
SEDGEWICK_AB
|
06/04/2015
|
52.8
|
-111.7
|
OLDS_AB
|
06/04/2015
|
51.8
|
-114.1
|
LETHBRIDGE_AB
|
06/04/2015
|
49.7
|
-112.8
|
GRANDE_PRAIRIE_AB
|
06/04/2015
|
55.2
|
-118.8
|
BEISEKER_AB
|
06/04/2015
|
51.4
|
-113.5
|
LETHBRIDGE_AB
|
05/04/2015
|
49.7
|
-112.8
|
KINDERSLEY_SK
|
05/04/2015
|
51.5
|
-109.1
|
BEISEKER_AB
|
05/04/2015
|
51.4
|
-113.5
|
LETHBRIDGE_AB
|
04/04/2015
|
49.7
|
-112.8
|
Forward Trajectories (FT)
Forward trajectories originating from the following locations are predicted to cross the prairies within the next five days:
Forward Trajectory source locations predicted to cross the Canadian prairies
|
Location ID
|
Initial Date
(dd-m-year)
|
BOZEMAN_MONTANA
|
07/04/2015
|
EASTERN_WASHINGTON
|
07/04/2015
|
IMPERIAL_VALLEY_CALIFORNIA
|
07/04/2015
|
MEXICALI_MEXICO
|
07/04/2015
|
MOSCOW_IDAHO
|
07/04/2015
|
BOZEMAN_MONTANA
|
06/04/2015
|
EASTERN_WASHINGTON
|
06/04/2015
|
LOUISIANA
|
06/04/2015
|
MANHATTAN_KANSAS
|
06/04/2015
|
MOSCOW_IDAHO
|
06/04/2015
|
SANTA_MARIA_CALIFORNIA
|
06/04/2015
|
BOZEMAN_MONTANA
|
05/04/2015
|
EASTERN_WASHINGTON
|
05/04/2015
|
MANHATTAN_KANSAS
|
05/04/2015
|
EASTERN_WASHINGTON
|
04/04/2015
|
MANHATTAN_KANSAS
|
04/04/2015
|
MOSCOW_IDAHO
|
04/04/2015
|
EASTERN_WASHINGTON
|
03/04/2015
|
MOSCOW_IDAHO
|
03/04/2015
|
The April 6 forward trajectory from Santa Maria, California, is
predicted to cross over southern Alberta on April 11. The forward trajectory from
Mexicali should cross southern Manitoba about April 8. The Imperial Valley trajectory is
predicted to cross southern Manitoba on April 9.
Though the prairies were forecasted to expect snow (April 7), conditions are
predicted to warm up over the next few days.
Forecast for Lethbridge:
Forecast for Winnipeg: