Perspectives of the Saskatchewan River Basin

Transcription

1 Perspectives of the Saskatchewan River Basin Allan Howard, National Agroclimate Information Service, Agriculture Agri-Food Canada, Regina Saskatchewan Presented to the IISD-GWSP Conference on the Water-Energy-Food Security Nexus May, 2012

2 A critical water resource for the prairie provinces of Canada 80% of Saskatchewan River water comes from the Rocky Mountains 40-50% of basin does not contribute to river flows < 1% of flow originates in Saskatchewan, but 70% of population uses river water 86% of consumption of South Saskatchewan River goes to irrigation 2

3 Saskatchewan River Basin Covers 405,864 Km 2 including 2 countries and 3 provinces 4th longest river in N. America Population > 3 million 2.4 million in Edmonton Calgary corridor One of the fastest growing economies in North America Challenging climate One of the most variable in the world; extreme events are normal Moisture deficit Competing water usage 3

4 Management Issues Water demand is increasing, growing economy, growing population yet the South Saskatchewan River has reached limits for use in southern Alberta Climate change and land management are changing the land and its water in complex ways, affecting river flows and prairie hydrology Pollution is changing its water quality Water governance in the prairie provinces is complex and fragmented 4

5 Climate Issues Droughts ; 2006, 2009 Floods & Excess moisture & & 2010 SSRB: 15% decline in actual flow 5

6 Difference from Normal (mm) Cumulative effects of wet and dry years Saskatoon

7 Difference from Normal (mm) Difference from Normal Cumulative effects of dry years Beaverlodge, Alberta YEAR 7

8 Pacific Decadal Oscillation NOAA,

9 A strong negative relationship exists between the PDO and Canadian Prairie streamflow Stewart et al. (2005) Rood et al. (2005) Gobena and Gan (2006) St. Jacques et al. (2010) + Positive PDO warmer, drier winter Negative PDO colder, wetter winter Correlation r between winter PDO and winter precipitation,

10 Annual natural flow, South Saskatchewan River at Medicine Hat source: PPWB

11 Historic Climate Reconstructed Departures From Median Precipitation June - July Precipitation Medicine Hat, Alberta, August - July Precipitation, Havre, Montana, D. Sauchyn

12 departures from the mean North Saskatchewan River at Edmonton, Sauchyn et al

13 Most Probable Impacts from Climate Change More frequent departures from average conditions More extreme events Lower flows: Lower runoff/streamflow in watersheds originating in the Rocky Mtns and western prairies Reduced snowpack in mountains and southern prairies Peak snowmelt moves to March-April-May Low flows in the summer-fall-winter; routine water shortages Warmer summers increase agricultural demand for water. Irrigation water shortages in SSRB become common 13

14 Water Quality Degraded Lower flows will compound nutrient loading problems 14

15 Saskatchewan River Basin History of Research to build upon 15

16 Study Proposal Research network brought together to study the interrelationship of land surface and atmospheric processes Better understanding of the how climate change, land surface changes and water-energy balance will impact water availability Saskatchewan and McKenzie basins Become part of GEWEX Considerable investment 16

17 Study Proposal Four themes: Improved Understanding and Modelling of Change in Cold Region Environments Upscaling for River Basin Scale Prediction Analysis and Prediction of Large Scale Change Outreach and Dissemination State-of-the art infrastructure and strong interdisciplinary collaboration to deliver new science at the interfaces between the physical sciences, engineering and social science 17

18 Howard Wheater

19 Summary The Saskatchewan River Basin represents a set of key challenges for science and society in terms of Adaptation to climate variability and change Water and land use Sustainability: food, water, environment, economy How do we build the case that improving our understanding of how land, atmospheric and socioeconomic factors interact can enable informed decision making to avoid the problems that have happened in other countries and allow Canada to gain advantages in food, water and economic security? 19

20 Thank You! Allan Howard