Oh boy we are in trouble now. The sea level is rising, only very, very slowly. According to a peer reviewed study presented by the University of Leeds. reports that icebergs floating in the oceans near the poles are melting, and that melting ice is most assuredly causing sea levels to rise. But before you go sell your oceanfront property, or invest in a new rowboat, relax, you have some time we are talking about 49 millionths of a meter every year. Putting that in perspective, in a little more than 518 years, 134 days, 3 hours and 45 minutes, the sea level would have risen a total of one inch.
The research, published this week in Geophysical Research Letters, is the first assessment of how quickly floating ice is being lost today.
According to Archimedes’ principle, any floating object displaces its own weight of fluid. For example, an ice cube in a glass of water does not cause the glass to overflow as it melts.
But because sea water is warmer and more salty than floating ice, changes in the amount of this ice are having an effect on global sea levels.
The loss of floating ice is equivalent to 1.5 million Titanic-sized icebergs each year. However, the study shows that spread across the global oceans, recent losses of floating ice amount to a sea level rise of just 49 micrometers per year – about a hair’s breadth.
According to lead author Professor Andrew Shepherd, of the University of Leeds, it would be unwise to discount this signal. “Over recent decades there have been dramatic reductions in the quantity of Earth’s floating ice, including collapses of Antarctic ice shelves and the retreat of Arctic sea ice,” said Prof Shepherd.
“These changes have had major impacts on regional climate and, because oceans are expected to warm considerably over the course of the 21st century, the melting of floating ice should be considered in future assessments of sea level rise.”
Professor Shepherd and his team used a combination of satellite observations and a computer model to make their assessment. They looked at changes in the area and thickness of sea ice and ice shelves, and found that the overall signal amounts to a 742 cubic kilometres per year reduction in the volume of floating.
Because of differences in the density and temperature of ice and sea water, the net effect is to increase sea level by 2.6% of this volume, equivalent to 49 micrometers per year spread across the global oceans.
For those of you who want to sit and watch the oceans take over the sea shores, may I suggest the extra large vat of popcorn, because you are going to be sitting for a very long time. If you start getting bored, you may want to take a break and watch grass grow, that will be much more exciting.