Ask A Scientist

If the polar ice caps melted because of global warming, would the whole earth flood?

Asked by: Mychal Zechariah Lozada
School: Owego Apalachin Middle School
Grade: 6
Teacher: Chris Mahon
Hobbies/Interests: N/A
Career Interest: N/A

Answer from Tim Lowenstein

Professor of Geology, Binghamton University

Research area: Geochemistry, Paleoclimatology, Long-term preservation of microorganisms and ancient DNA.

PhD school: Johns Hopkins University

Family: Wife Sally (teacher at Vestal High School), daughters Maggie, 19, Willams College, and Kirby, 14, 8th grade, and son Scott, 16, 11th grade.

Interests/hobbies: running, skiing; to relax- organic gardening and reading; to get away from it all- traveling to interesting places

Web page

If all the ice on Earth melted, the water formed would eventually end up in the oceans and cause sea level to rise.  We know how much ice exists on Earth and how much water is in the ocean.  From that information, we can make an accurate estimate of how much sea level would rise if all of the ice on Earth melted.  Melting of Greenland’s ice cap would cause sea level to rise 6.6 meters (21.6 feet).  Antarctica has much more ice than Greenland.  Melting all the ice on Antarctica would raise sea level 73.4 meters (241 feet).  Melting all other ice on Earth (mountain glaciers, sea ice) only raises sea level 0.5 meters (1.6 feet). If all the ice on Earth disappeared, then the total rise of sea level would be 80 meters (262 feet). Would the whole Earth flood? No. But low lying areas along the Atlantic and Gulf Coasts of the United States would be underwater. New York, New Jersey, and all the coastal states down to Florida would get smaller. Philadelphia, New York City, and Washington, D.C. would disappear.  The Gulf Coast states, especially Louisiana and Texas would have coastlines tens to hundreds of kilometers inland. California would not fare as badly because it has raised land right along the coast.  What about Binghamton? The low-lying river valleys in our region are about 250 meters (820 feet) above sea level.  We would therefore be safe, more than 170 meters (560 feet) above the flooding elevation.  There has been much discussion in the news about the harmful consequences of sea level rise due to global warming. It has been estimated that if sea level were to rise 10 meters (33 feet), 25% of the people in the United States would need to relocate.  Scientists predict that sea level will rise less than 1 meter (3 feet) over the next 100 years.  But don’t let such seemingly small changes in sea level fool you.  There could be costly impacts on coastal habitats such as flooding, erosion and contamination of freshwaters by seawater, called salt-water intrusion

Last Updated: 3/1/17