sea level

How fast are seas rising?

The NASA post NASA Uses 30-Year Satellite Record to Track and Project Rising Seas (3/17/2023) has this to say (with calculus language): Since satellites began observing sea surface height in 1993 with the U.S.-French TOPEX/Poseidon mission, the average global sea level has increased by 3.6 inches (9.1 centimeters), according to NASA’s Sea …

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How much has sea level risen locally?

If you’d like local trends of sea level rise then check out NOAA’s Sea Level Trends page. The sea level trends measured by tide gauges that are presented here are local relative sea level (RSL) trends as opposed to the global sea level trend. Tide gauge measurements are made with …

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How much will tidal flooding increase?

Sea level rise will increase the likelihood of tidal flooding. NASA has posted a tool, Flooding Days Projection Tool, to help understand how much tidal flooding may increase. There is a drop down menu for numerous locations in the U.S.  For example, the graph here is for Kings Point, NY.  …

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What contributes to sea level rise?

The Climage.gov article Climate Change: Global Sea Level by Rebecca Lindsey (1/25/2021) provides a nice overview of rising sea levels. It is easy to forget that thermal expansion of water is a significant contributor to sea level rise. Global mean sea level has risen about 8–9 inches (21–24 centimeters) since …

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How frequently are high tides occurring?

NASA’s Vital Signs of the Planet article Beating Back the Tides by Jenny Marder (11/11/2020) provides an update on the increasing frequency of high tides (see the graph copied here for one example). Between 2000 and 2015, high-tide flooding in the U.S. doubled from an average of three days per …

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How much has sea level changed?

NASA’s Vital Signs of the Planet Sea Level Sea Level page provides data on sea level. For example, since 1993 sea level has increased  by about 94mm, but this is an average. In their Sea Level 101, Part Two: All Sea Level is `Local’ by Alan Buis (7/14/2020) they provide …

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How do we calculate sea level?

If you aren’t sure how sea level is calculated then read NASA’s Sea Level 101: What determines the Level of the Sea? by Alan Buis (6/3/2020) . Here is one factor: If our ocean had no tides or currents, the sea surface would assume the shape of the geoid. These …

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