warming_qanda_n3jpegEarth’s oceans are the greatest influence on global climate. Only from space can we observe our vast oceans on a global scale and monitor critical changes in ocean currents and heat storage.  Topography is the shape of a surface, including its relief.   The topography of the sea surface is influenced by both gravity and ocean circulation.  Altimetry is the measurement of the height of the sea surface above (or below) some reference level. Every 10 days, Jason measures heights of more than 90% of the world’s ice-free oceans with the radar altimeter and completes 127 revolutions, or orbits, around the Earth. The science objectives are:

  • Measure global sea-height change and provide a continuous view of changing global ocean surface topography
  • Calculate the transport of heat, water mass, nutrients, and salt by the oceans
  • Increase understanding of ocean circulation and seasonal changes and how the general ocean circulation changes through time
  • Provide estimates of significant wave height and wind speeds over the ocean
  • Test how we compute ocean circulation caused by blowing winds
  • Improve the knowledge of ocean tides and develop open- ocean tide models
  • Improve climate forecasting and predictions
  • Describe the nature of ocean dynamics and develop a global view of Earth’s oceans
  • Monitor the variation of global mean sea level and its relation to global climate change