Historic variability and trends. Data Sources Weather stations Modeled climate

Transcription

1 Historic variability and trends Denise Neilsen 1, Alex Cannon 2,Bill Taylor 2, Istvan Losso 1, Grace Frank 1 and Ron Fretwell 3 1 Agriculture and Agri- Food Canada, PARC, Summerland, BC. 2 Environment Canada, PYR, Vancouver, BC 3 RHF Systems, Kelowna, BC Osoyoos Lake Water Science Forum, Sept th, 2011 Osoyoos, BC. Data Sources Weather stations Modeled climate Future climates Limiting factors for natural and managed ecosystems Data Use Water supply demand modeling Other uses Highly variable Best illustrated by weather integrators Snow accumulation hydrology Water use Winters are getting less cold Summers warming in the south o C Getting Wetter ~20% Courtesy Pacific Climate Impacts Consortium, Victoria, BC

2 Seasonal average daily maximum temperature by year ( C) Winter Spring ºC per year ºC per year Summer Fall ºC per year ºC per year Seasonal average daily minimum temperature by year ( C) Winter Spring ºC per year ºC per year Summer Fall nil trend nil trend Source: Bill Taylor and Mark Barton Environment Canada - PYR Source: Bill Taylor and Mark Barton Environment Canada - PYR Seasonal total precipitation by year (mm) Winter Spring Nil trend 0.43 mm per year Fall Summer Nil trend 0.62 mm per year Precipitation Area Average (Vernon CSR, Summerland, Kelowna A, Penticton A) Source: Bill Taylor and Mark Barton Environment Canada - PYR Number of stations Number of reporting EC weather stations within the Okanagan <500m m m >1500m Total Environment Canada, BC Ministries responsible for Environment, Forestry and Transportation Increasingly sparse weather data to characterize climatic variation

3 Weather station reports Environment Canada Growers Supply Network Water Demand models 750 m 350 m Snowpack, hydrology models 2200 m 1850 m 350 m 400 m Habitat models Complex terrain Limited station data particularly at high elevation Basis for historic and future climate downscaling Interpolates daily minimum and maximum temperature and precipitation from weather station data Takes into account Latitude Elevation Distance to major Lakes Temperature inversion Feb Produces daily temperatures and precipitation at a 500x500m spacing (grid) ~32000 grid cells Daily precipitation and min/max temperature Climate change analysis based on 6 Global Climate Model outputs with two greenhouse gas emissions scenarios Statistically downscaled using synoptic map typing and a weather generator Neilsen et al Can. Water Res. J. 35 Cannon et al Monthly Weather Review, 130 Cannon et al Journal of Hydrometeorology.

4 Daily Precipitation Daily Min/Max Temp. Grid Cell calculations Potential Evapo- transpiration ET 0 (P. M. FAO 56) Form of precipitation (Rain/ snow) Snow water equivalent Agricultural climate indices Growing Degree Days Base 5 C, 10 C (GDD) TSUM (range of values) Crop growing season Frost free days (FFD) Resolution of GCMs ~400km x 250km Downscaled statistically to meet regional needs To give fine resolution climate data 500mx500m Projected slight increase or little change in precipitation. Form (snow/rain) and timing within the year may change

5 Projected gradual increase in the highest temperatures in the basin. Less extreme under the low greenhouse gas emissions scenario. Implications for crop suitability, ecosystems Projected gradual increase in the lowest temperatures in the basin. Less warming under the low greenhouse gas emissions scenario Implications for vegetation and insect survival ACTUALS days Valley bottom days CM21_A2 CGCM31_A2 Potential 25% increase in growing season length by end of century under high GG emissions. Less under low emissions days days CM21_B1 Low GHG days days ACTUALS Suitable for premium wine production

6 ACTUALS GGD10 Valley bottom GGG10 CM21_A2 CGCM31_A2 Up to 100% potential increase in accumulation of GGD10 by the end of the century. 0 Less under low emissions GGD GGD Implications 800 for invasive species, crop 1200 suitability CM21_B Low GHG GGD days ACTUALS mm Valley bottom mm CM21_A2 CGCM31_A2 Potential 25% increase in ET by end of century under high GG emissions. Less under low emissions mm mm CM21_B1 Low GHG mm mm Gradual increase Actual ET lower Water limitations in natural ecosystems change in vegetation to adapt Crop water use may range from 40 to 100% of potential ET, depending on crop type Water Supply Water Demand Lake Evaporation Study SW Hydrology Study Groundwater Study Climate Models Various Studies of Water Management and Use Hydrology Model In stream Flow Study Water Demand Model Current and Future Supply Current and Future Demand Water Accounting Model

7 Irrigation ends Oct. 1 Historic trend Range of projections AAFC HOBO Network Hourly temperature data Relative Humidity at some sites 150 sensors High and low elevation data Model Improvement Temperature lapse rates Cold air drainage models New Model Uses Crop and Insect development models Number of statitions Number of reporting weather stations within the Okanagan <500m m m >1500m Total Too few weather stations to continue with the current process New methods under development for S. British Columbia (Cannon et al.)

8 Questions?