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~~ ~r~s ~~ !_}~ ater is the liquid state of a chemical compound whose molecular formula is H2O-two atoms of hydrogen and one atom of oxygen. This combination can exist under normal pressures as a solid, a liquid, or a gas. This characteristic is highly unusual for any compound in the chemical world. When I think of a compound, I visualize molecules dancing around within its structure. Each molecule does so to its own tune. So compounds composed of different types of molecules react differently. In the case of water, I see the molecules becoming very agitated when the liquid is heated, so at a boiling temperature of 212° F the water molecules are flying around like mad and leave the water as steam. Between 212° F and the freezing point of 32° F water is more stable, but molecules still leave from time to time, their numbers depending upon the temperature of the water and the condition of the air. Water does evaporate. Below 32° F, the water molecules line up, become ice, and remain reasonably stable. Ice does evaporate slowly, however, as some molecules can't stand the confinement of ice and fly away as evaporation. Ice can disappear from your sidewalk, slowly but surely. Liquid water can yield a record of its environment. Water occupies the lowest part of its immediate space, and therefore becomes Mother Nature's sewer. What goes up most come down, and when it comes down, into the sewer it goes to remain as a precipitate, a sediment, if it doesn't flow away. So, the sedimentary beds of lakes, wetlands, rivers, and oceans can serve as environmental books to read. Many areas of the world have sedimentary beds dated hundreds of millions of years ago and are most valuable in tracking the history of our earth. Ice, however, seems to deliver the cleanest and clearest record of what occurred at any particular time within its existence, which can be anything from yesterday to a million years ago. Sediments can deliver records of the environment dated hundreds of millions of years ago, but the data is limited. It has been proven that glacial ice is a breed of its own, being most stable and able to retain records of diverse environmental factors and components, including fossil gases. Nothing is perfect and retrieving a complete and accurate record of hundreds of thousands of years ago with today's sophisticated equipment is still a matter of "you get what you get," but what you get is most valuable. I started this article with the intention of detailing ice-coring on Greenland, a project that has been underway for several years under the auspices of several nations, including America. The whole thing is fascinating and awesome when you consider a team is drilling a five to eight inch hole through ice 10,000 feet thick, bringing ice cores to the surface and preserving them for detailed study in laboratories around the world. The cores are like vertical tree rings, bands of annual happenings such as variations in temperatures, precipitation, deposits of volcanic ash, gases trapped in bubbles, and other items of the atmosphere that were affecting our world in times past. However, starting work on such an article led me quickly to the proposition of structuring several more articles. These will be intended to show the preservative powers of ice, especially when under great pressures. Stay tuned! ; ~~~i ~h ~~f/. .~!ii: ~. 1(~~; ri ~~1,C..i~d~~t1-'t ~r)~1 .: ~(~~14 +iui -lilt ).1(, ~'. ! ii~~~ll ~t1i2ti ~i~I~ . ~~(' I J i COY; i! ~i'~(i ~ ~ ] ~~'~il ~L Ih~+ .f' 4~~ UIfF:-~ ~t~l hiii~ ~ ~~'~i i ~~~ ~'f-~~U~:'i7l i~~ll'r'. ~~ << t,~~~il , ~,~a(i~r~ FACETS Summer 2002 Glacier ice retains records of diverse environmental factors and components.