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American and European scientists have new equipment to watch the world’s oceans. The Jason-3 satellite launched in January. It is designed to record rising sea levels. Scientists say satellite information recorded over the last twenty years shows sea levels rising fast. They say the fast rising seas are an indicator of climate change. Josh Willis is the Lead Project Scientist for the operation at NASA. He says the Jason-3 satellite collects information using radar. He explains that satellite records have been kept for only about 25 years. But measurements of how the oceans have been changing go back thousands of years. He says the past 2000 years have been stable in terms of sea level and the Earth’s temperature. But in the past one hundred years sea levels have risen quickly. He says that is because of the warming of Earth. All material, including water, expands when heated. The Jason-3 satellite measures how high the surface of the sea is. This permits scientists to estimate how much extra heat is stored in the ocean. Eric Leuliette is with the National Oceanic and Atmospheric Administration. He says sea levels are an expression of climate change for two reasons. He says excess heat is causing the ocean to expand. And, he says the planet’s warming causes glacial ice to melt into the oceans and increase sea levels. Leuliette says Jason-3 information will help scientists monitor the effects of rising sea levels. He says it will also help in predicting, and preparing for, big storms.