1001 Space Earth Earth Rocks and Minerals Landscape Sea Weather and Climate Natural Disasters Resources Nature History Human World Science and Technology

Choose a Page:How long has there been life in th...How much of the Earth is covered b...Why does seawater taste salty?Is the ocean floor flat?What causes waves?What is an iceberg?Are tidal waves caused by the tides?What are ocean currents?*How has the ocean bed been measured?*How does the sea affect the climate?How do coral reefs form?Are there currents at great depths?Why does the tide come in and go out? How has the ocean bed been measured? The Seasat satellite was able to measure variations in the height of the sea bed using radar. It built up a picture of the average surface level of the sea by measuring the reflection time of radar waves off the sea's surface. A surface level above average indicated a steep slope on the sea bed. In three months, the Seasat satellite plotted the heights of more than 50 million locations.   Previous: Back Book: 1001 Section: Earth Chapter: Sea