In development for nearly 20 years with contributions from counterparts in Canada and the UK, SWOT was one of 15 missions listed by the National Research Council as projects NASA should undertake in the coming decade.
Climate Tipping Point?
A major thrust of the mission is to find out how the oceans absorb atmospheric heat and carbon dioxide, in a process that naturally moderates global temperatures and helps mitigate climate change.
Scientists estimate that the oceans have absorbed more than 90% of the excess heat trapped in Earth’s atmosphere by human-caused greenhouse gas emissions.
Scanning the oceans from orbit, SWOT will be able to measure fine differences in surface height around small currents and eddies where much of the ocean’s heat and carbon is thought to be lost.
Understanding that mechanism will help answer an important question – what is the tipping point at which the oceans begin to release large amounts of heat back into the atmosphere instead of absorbing it, thus limiting global warming rather than limiting it. Let’s speed it up.
SWOT’s ability to discern even very small surface features over much wider areas than previous satellites will help study the effects of sea level rise on coastal areas.
Freshwater bodies are another major focus of the SWOT, which inspects the entire length of nearly all rivers wider than 330 feet (100 m), as well as more than 1 million lakes and reservoirs larger than a few New York City blocks. are equipped for.
Taking inventory of Earth’s water resources repeatedly aboard SWOT’s three-year mission will help researchers better trace seasonal changes and fluctuations in the planet’s rivers and lakes during major weather events.
SWOT’s radar instrument operates at the Ka-band frequency of the microwave spectrum, allowing its scans to penetrate cloud cover and darkness and map observations in two dimensions.
Previous studies of water bodies relied on data taken at specific points or from satellites that could only track measurements along a one-dimensional line.
The satellite is expected to begin producing research data within months.