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Agriculture and Agri-Food Canada ’s National Agroclimate Information Service’s Drought Monitoring. Trevor Hadwen Agriculture and Agri-Food Canada, Agri-Environmental Services Branch (AESB) National Agroclimate Information Service (NAIS) Global Drought Assessment Workshop
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Agriculture and Agri-Food Canada’sNational Agroclimate Information Service’s Drought Monitoring Trevor Hadwen Agriculture and Agri-Food Canada, Agri-Environmental Services Branch (AESB) National Agroclimate Information Service (NAIS) Global Drought Assessment Workshop Asheville, NC, April 22, 2010
Drought – more than just lack of rainfall Drought can mean many different things to different people • Depending on: • A regions normal climate • Specific needs of various sectors • Main categories of drought are: • meteorological • agricultural • hydrological • socioeconomic Most drought indices we use measure meteorological drought The availability of water depends largely on rainfall, (but) the concept of drought cannot be divorced from the use to which water is put. Gibbs & Maher (1967):
Drought Watch Website Goals: • To provide timely information of the impacts of climatic variability on water supply and agriculture in Canada. • To promote practices that reduce drought vulnerability and improve management during a drought. The site includes • Current Condition and Historical Maps • Climate Profiles • Drought Management Information • Federal Programs • Provincial Links • Related Websites • Farm Stress Information • Products include: • Seasonal and annual Products for Moisture • indicators • Rolling Percent of Average Precipitation • - 7-day out to 5 years • Rolling Accumulated • - 7-day out to 5 years • Dry Spell indicator • - 7, 14, 30, 60… days with < 0.5 mm • - Consecutive days with < 0.5 mm • Departure from Normal Precipitation (Rolling) • - Set time periods (7-day out to 5 years) • - Seasonal • Temperature • - Max/Min temperature over 7-days • - Heat waves / Dry spells • Growing Degree Days (Base 0, 5, 10, and 15) • Corn Heat Units Over 500 maps produced daily www.agr.gc.ca/drought
National and Regional Products Canada is broken down into 5 regions
Time Specific Products • Agricultural year • Growing season • Winter season • Deciles • Percent of normal • Accumulated PPT • Departure from average
National Drought Model: SPI Calculated Monthly
National Drought Model: Soil Moisture The Drought model uses a simplified water balance approach (modified VSMB)
MODIS - Remote Sensing Products: Weekly MODIS NDVI 7-day composites • Advantages of the MODIS System • National Coverage • Better resolution • Better analytical features • Data is free of charge from USGS • Data back-up system is incorporated • Opportunity to use other Indices
Prairie Drought Impact Monitoring On-Farm Surface Water Supply and Forage Monitoring Program Forage Production Forage Supplies On-Farm Surface Water Supplies
Monitoring Outside the Agricultural Extent • Lack of station data for northern regions. • Lack of understanding of drought assessment and drought issues in northern areas, especially north of the treeline. • Research is required on how to address these issues. • First priority is to improve monitoring in the boreal regions. • We need to develop relative indicators for northern regions. CFS currently uses Absolute indicators. • Remove sensing may be able to assist in some regions.
International Collaboration and Drought Analysis • A consolidation of indices and indicators into one comprehensive national/continental drought map • Captures the drought’s magnitude (duration + intensity), spatial extent and impacts
Thank You Trevor Hadwen trevor.hadwen@agr.gc.ca
Challenges for Drought Monitoring in Canada • Canadian environment is complex and drought indices need to be utilized in a way that reflects this. • Increased need for timeliness and accuracy in determining extent location and severity of climate impacts. • Quality and quantity of data is incomplete. Data density and length of record are both significant challenges. • Uncertainties exist in index calculation, mapping and interpretation. Testing and calibration should be encouraged • Winter (Snow) – Hard to measure, it tends to move around before the moisture is accessible (Blowing, runoff, sublimation). Indices do not account for this.