Analysis of Agrometeorological Indices in the Context of Climate Extremes on the Canadian Prairies Asn Chipanshi, Patrick Cherneski, Yinsuo Zhang, Nathaniel Newlands & Dongzhi Qi Science & Technology Branch, AAFC
Overview This study builds on a previous federal project which created 12 extreme climate indices for Canada based on temperature, precipitation, wind and heat help assess climate risks agricultural production. This analysis looked at the spatial TRENDS, VARIABILITY and CHANGE over time for 4 of the 12 indices for the Canadian Prairie region. 2
Extreme events are increasing frequent and severe Wind Insects Snow Hurricane s Humidity Wildfires Heat Waves Frost Tornadoes Disease Thundersrms Excess Moisture Hail Lightning
Recent events compared hisric 2013, flooding in Alberta 2015, drought in Alberta 4
The Canadian Prairie Agricultural Region and Stations 12/02/2011 5
Agrometeorological Indicars EGDD: effective growing degree days, heat units above 5 o C, taking in account the pho-period length Water Demand: (P-PE) where P=Precipitation, PE=Potential Evapotranspiration (Baier & Robertson, T-based). SPEI: Standardized Precipitation Evaporation Index, uses P- PE as an input variable; Log-Log function used for SPEI parameters. Extreme Heat: 30 o C threshold, warm season crops. 1950 2012, homogenized and gridded climate daily data sets, approximately 75 stations 6
Heat Units are Increasing 7
Effective Growing Degree Days (EGDD) for different field crops in Canada Crop type Cool season crops Warm season crops Crop name Wheat Oats Barley Canola Corn Beans Soybeans EGDD Range 1538 1680 1483 1750 1269 1540 1152 1445 1173 1779 1100 1300 1186 1719 Criteria On average, cool-season crops: 1485 On average, warm-season crops: 1375 8
The Growing Season trend is Increasing 9
Number of Frost-Free Days required for field crops reach maturity on the Prairies Crop type Cool season crops Warm season crops Crop name Wheat Buck wheat Oats Barley Canola Corn Beans Soybeans Range 83 103 70 90 82 98 70 90 85 102 100 120 85 100 105 120 Criteria On average, cool-season crops: 87 days On average, warm-season crops: 105 days 10
Water Demand is Increasing 11
The SPEI Results are Mixed 12
The Number of Days >30 o C is mostly Increasing 13
1950 2010 Trend in Growing Season Length -Oldman Basin (days/decade) 14
Near Pincher Creek AB: Near Taber AB: from 179 196 days from 188 222 days Near Picture BuJe AB: Overall, there is an increase in the length of the growing season from 188 209 days
Near Pincher Creek AB: from 190 165 days Near Taber AB: from 182 170 days Near Picture BuJe AB: from 182 175 days Overall, there is a reduction in the number of frost days
Near Pincher Creek AB: from 60 mm 71 mm Near Taber AB: from 50 mm 54 mm Near Picture BuJe AB: 56 mm, no change Overall, there is a minor increase in 5-day rainfall tals
Near Pincher Creek AB: Near Taber AB: from 20 39 days from 19 32 days Near Picture BuJe AB: from 21 39 days Overall, there is an increase in temperatures
Summary and Going-Forward Heat units trended upwards, statistically significant. The growing season trended upwards, but was statistically significant at only a few locations. Water demand trended upwards, generally in the southern areas, strongest in Saskatchewan (SK). The SPEI results were mixed, with a trend wards drying, particularly in SK. Days >30 o C trended upwards in Alberta and southern SK. Our preliminary findings agree with warming trends reported by Bonsal et al (2001) for southern Canada (1900-1998). 19
Summary and Going-Forward continued... An increasing trend in P (for the growing season) was found by Lucie and Vincent (2014) and may explain our trend result in P-PE and SPEI at some locations. Going-forward, all 12 extreme climate indicars will be analyzed with the current methodology. All 12 indicars will also be re-calculated using World Climate Research Programme CMIP5 data. References BONSAL, B.R.; X. ZHANG, L.A. VINCENT and W.D. HOGG. 2001. Characteristics of daily and extreme temperatures over Canada. J. Clim. 14: 1959 1976. VINCENT L.A and MEKIS E. 2014. Changes in Daily and Extreme Temperature and Precipitation Indices for Canada over the Twentieth Century. Atmosphere- Ocean, 44:2, 177-193, DOI: 10.3137/ao.440205 20
For more info: Asn Chipanshi National Agroclimate Information Service asn.chipanshi@agr.gc.ca 306.523.6790 www.agr.gc.ca/drought 21