TONY HAYS, San Clemente
Gregg Newbury’s letter in last week’s San Clemente Times asked an interesting question: If sea levels are rising, where is the water coming from?
According to sealevel.nasa.gov, the answer is that the rise in ocean levels is due to two effects. Two-thirds of the rise comes from water being added to the ocean from melting ice, and one-third from expansion of ocean water due to increase in water temperature.
Of the ice melt, about two-thirds comes from Greenland and about one-third from Antarctica. But Gregg also assumes that “snow and ice are pretty much a result of ocean water freezing from the cold temperatures,” and this turns out to be an incorrect assumption.
Both the Greenland and Antarctic ice sheets are the result of snow falling over long periods of time. When falling snow is compressed into ice, it also traps air and other chemicals. This enables scientists to determine the composition of the atmosphere many thousands of years ago.
The National Science Foundation Ice Core Facility (icecores.org) drills and collects ice cores. It has data on Greenland ice going back 130,000 years, and Antarctic ice going back 800,000 years.
These records show that the current CO2 level in the atmosphere is significantly higher than it has been at any time in the past 400,000 years, and this level is rising rapidly.
Current trends must be reversed if we are to avoid a climatic disaster. One way to slow down the increase in atmospheric CO2 is to impose a fee on chemicals that produce greenhouse gases when burned, as proposed in the U.S. Congressional bill H.R. 763.
This fee would be returned as a dividend to all U.S. households. This is just one of many actions that must be taken if we are to slow down the rate of sea-level rise. The U.S. should coordinate a worldwide effort and set an example to the rest of the world as to what must be done.