The rising and falling of the sea is a phenomenon upon which we can always depend. Tides are the regular rise and fall of the sea surface caused by the gravitational pull of the moon and sun and their position relative to the earth. There are some factors that cause the tides to be higher than what is "normally" seen from day to day. This bulletin tells you when you may experience higher than normal high tides for the period of time between March and May 2017.
Did you know that NOAA offers many earth science professional development resources, including free distance learning opportunities as part of our unique Climate Stewards project? Check out some of our recent broadcasts on topics including modeling our planet's climate to making climate communication stick. Sign up to be notified of upcoming presentations and join the conversation.
True tides—changes in water level caused by the gravitational forces of the sun and moon—do occur in a semi-diurnal (twice daily) pattern on the Great Lakes. Studies indicate that the Great Lakes spring tide, the largest tides caused by the combined forces of the sun and moon, is less than five centimeters in height. These minor variations are masked by the greater fluctuations in lake levels produced by wind and barometric pressure changes. Consequently, the Great Lakes are considered to be non-tidal.
GIS is a computer system that captures, stores, checks, and displays information related to positions on Earth's surface. It helps analysts and scientists study climate change, land use planning, business, and even our nation's defense. You might use it to find the closest restaurant or book store using your phone's GPS. At NOAA, GIS is used to map oil spill trajectories and historic hurricane tracks, view and analyze nautical charts, and understand trends in areas such as sea level change and coastal socioeconomics.
National Ocean Service | NOAA | Department of Commerce
Revised: March 23, 2017 | You are here: http://oceanservice.noaa.gov/welcome.html