Tuesday, January 19, 2010
We finished our trip by spending the morning at Mammoth Terraces. Large, perfect snowflakes drifted onto us as we learned about Yellowstone's geysers from Park Ranger Beth Taylor. Beth taught us a neat acronym to remember that it takes a P2HEW (pronounced “few”) for a geyser to work.
We already knew that geysers need water (W) and heat (H) to work. Beth explained that geysers also need earthquakes (E). Earthquakes open and close cracks in underground rocks. These cracks form the so-called “plumbing system” of a geyser. Depending on what cracks are opened or closed during an earthquake, an existing geyser might stop erupting or a new geyser might occur in a location where there wasn’t one before.
Pressure (P) is the driving force behind a geyser's eruption. Water trapped behind constrictions in a geyser's “underground pipes” (cracks in the rocks) is under very high pressure. When the water gets hot enough to flash to steam, the built-up pressure forces the steam to erupt out of the geyser.
While we easliy identified the first “P” as standing for pressure, we had a little trouble guessing what the second “P” represented. Beth told us that of the five places in the world that have concentrations of geysers, three of them — Iceland, South America, and New Zealand — have allowed the geysers and thermal features to be developed and used for energy. As a result, many of the geysers in these countries no longer erupt. In Kamchatka, Russia, the land is not protected and may someday be developed, so the future of Kamchatka's thermal features is unknown. However, due to the foresight of the people who established Yellowstone as the United States' first national park in 1872, the geysers in Yellowstone are protected — the final “P” — for future generations.
Although they did not realize it at the time, the people who protected Yellowstone for its unique thermal features also protected a number of other things: an incredible diversity of wildlife; an undeveloped space where the night sky is brilliant with stars; and a place where, if you walk only a short distance from the road, you can experience the cacophony of natural sounds without human interruption. In the future, if we as a nation continue to value and protect Yellowstone, we may well come to appreciate Yellowstone even more for things we can’t imagine now.
What do you value? If you could protect one thing in perpetuity — your house, your garden, your video game, you school — what would you choose to protect? What is it that you value? And what benefit might the thing that you choose to protect bring to others? Though we value many things, we have chosen to let Yellowstone into our hearts and have come to value this place. We hope you have, too.