Measuring altitude using your phone has become increasingly accurate and convenient, thanks to advancements in smartphone technology and the integration of various sensors. Here’s a comprehensive ...

For more than a decade, survey flights have crisscrossed the United States using gravity instruments to calculate a new sea level in an effort that will save the country billions of dollars on ...

A floodplain map has three key components: base map imagery and/or cartographic line work, an elevation model representing the earth’s surface or “terrain,” and flood study results generated from ...

Editor’s Note (10/16/19): This article has been edited after posting for inclusion in the November 2019 issue of Scientific American. A stunning 12 million people could be forced to retreat from ...

ABIQUIU LAKE, N.M. -- Throughout the 56 years the U.S. Army Corps of Engineers, Albuquerque District has been operating Abiquiu Lake as a flood control and water supply dam in the Chama River Valley ...

Visit NAP.edu/10766 to get more information about this book, to buy it in print, or to download it as a free PDF. The nation is presently making an investment of more than $200 million per year in ...