The Surface Water and Ocean Topography (SWOT) mission

Technology

The Canadian Space Agency (CSA) accepted NASA's invitation to participate in the SWOT mission by providing a key component of the wide-swath radar instrument – a set of extended interaction klystrons (EIKs). This is a modest contribution to this major US$1.2B investment but nevertheless crucial, as the EIKs amplify the power needed by the wide-swath instrument to generate the microwave pulses that are used to measure water surface elevation.

Communications & Power Industries Canada Inc. is world-renowned for its expertise in building this sophisticated device, as no other firms have a proven record of building and flying space-grade EIKs.

Science

Through this partnership, free access to SWOT data can now improve many water-related services in Canada, including flood and water level monitoring. This effort will help with implementing sustainable water management policies.

The SWOT international science team, including Canadian scientists from Environment and Climate Change Canada and Fisheries and Oceans Canada, is pursuing SWOT mission objectives and desired outcomes within two main areas of research, hydrology and oceanography, to enhance our understanding of:

• the water cycle across the country
• sea level variations in Canadian waters

Hydrology

Mission objectives and desired outcomes for hydrology research

Mission objectives	Desired outcomes
to measure the height and slope of fresh water bodies to calculate the rate of water gained or lost in lakes, reservoirs and wetlands to evaluate discharge variations in rivers and estuaries	to improve our estimation of surface water availability to assist in understanding important water-related hazards, such as floods and droughts to gain knowledge on the global water cycle

Oceanography

Mission objectives and desired outcomes for cceanography research

Mission objectives

Desired outcomes

to obtain precise measurements of ocean elevation features to measure small- and medium-scale features of the ocean's surface such as eddies and fronts

to better understand small-scale ocean circulation, which transports half of the heat and carbon from the upper to the deep ocean, a critical process linked to global climate change to help predict and characterize tides and storm surge features to improve ocean circulation numerical models leading to better prediction of ocean currents, weather and climate important for navigation, fisheries and offshore commercial operations

Marine safety and security

Example: Support the Canadian Coast Guard's search and rescue operations at sea by providing better information on water levelcurrents to more accurately forecast the water surface currents and the positions of drifting objects, ice and icebergs, oil spills or other potential contaminants.

Water management

Example: Environment and Climate Change Canada, in cooperation with provincial and territorial partners, monitors water level and flow at approximately 2500 key locations on lakes and rivers in Canada (Water Survey of Canada). Due to the complexity and cost of operating ground-based hydrometric monitoring gauges, especially in remote regions, this represents only a small fraction of the total number of lakes and rivers in Canada. SWOT provides coverage of most lakes and rivers up to four times every three weeks, including northern Canada, where very few measurements were taken previously. This global inventory of Canadian waters serves to improve our water management and assist in prediction of floods and drought.

Responsible resource development

Example: Measurements provided by SWOT benefit user communities such as structural engineers who use hydrometric data to optimize the design of various types of structures such as bridges, culverts, pipeline crossings, dams, reservoirs, hydroelectric plants, dykes and other water-related structures.

Conservation and protection

Example: Support sustainable management of fish habitat by providing relevant information derived from measuring water surface elevation of the oceans and freshwater water bodies such as major rivers and lakes. For example, these satellite-based measurements enable monitoring of streamflow in rivers and water storage in lakes, which are important parameters for fish migration and the availability of spawning and rearing habitat.

Marine transportation

Example: Provide optimized shipping routes based on accurate knowledge of marine currents, waves and water levels. These optimized shipping routes have demonstrated up to 8% savings on time and fuel for crossing the Atlantic, which represents a significant efficiency improvement for marine operators and reduces the risk of accidents.

Sustainable development in the North

Example: SWOT's high-valued data assists decision makers to better monitor the effects of climate change happening in the North. Information provided to the government on water quantity supports biodiversity and habitat assessments, as well as environmental prediction activities.