By using tree ring data taken from long-lived juniper trees—some of which are more than 1, years old—in the northern part of Yellowstone National Park, scientists can infer approximately how much water was available during a given year.
Without enough rain to recharge groundwater reserves, Old Faithful—likely along with many of the surrounding geysers—went dry. During the 13th century, Yellowstone was experiencing a prolonged period of severe drought.
A series of earthquakes in the area starting in caused the intervals between eruptions to increase by several minutes. The timing between intervals was further increased by the Turn of the Century Drought that struck the western United States between the years and , the worst dry spell in the region since the Medieval Climate Anomaly.
Pinson, J. America is changing faster than ever! Add Changing America to your Facebook or Twitter feed to stay on top of the news. And according to Cathy Whitlock, co-lead author and a professor at Montana State University, changes and preparation need to be made now if the ecosystem will be preserved.
Whitlock specializes in long-term environmental and climate change, and has spent four decades sifting through these sediment-rich lakes, publishing more than scientific papers on the topic.
Such a small shift may seem benign — until you realize that the last Ice Age was only about F 2. In recent decades, the average temperature in the park has been as high as or higher than in any period in the last 20, years, and could be the warmest of the last , years, according to the recent Yellowstone climate assessment. One clue as to what will happen next can be found by looking at plant fossils. Modern Yellowstone is known for thick pine forests, expansive geyser basins with grassy vistas that break the tree cover.
When the team analyzed the pollen buried in Goose Lake, they found that once the temperature heated up, the pine stopped growing and there was a sudden explosion of sagebrush and other grasses that do well in hotter climates. This points to drought at the time, Whitlock says. But as trees die off due to the hotter climate, forests may shrink in the coming decades, which will have a cascading effect: less forest and fewer tree roots mean more grass and more erosion.
Drier grass means fewer nutrients for large mammals. The severe 13 th century drought had significant effects well beyond Old Faithful Geyser. In fact, severe and persistent droughts impacted large parts of the USA and had a tremendous impact on indigenous peoples, including the Anasazi , Fremont , and Lovelock cultures. The full length of this sample covers the time period CE.
Since climate influences tree growth and the width of annual rings, the relation between ring widths and recent instrumental climate records air temperature, precipitation and river discharge is used to interpret climate variability in the distant past.
Wood from the lodgepole pines was preserved for over years on the geyser mound because it was near-continuously wetted by the alkaline, silica-rich thermal waters erupted from geysers. These waters deposit the mineral opal on tree stems and wood tissues which prevents the disintegration of cellulose by fungi, bacteria, and insects—it causes silicification , or mineralization, of the wood!
This silicification process can be rapid and take only days or weeks. Because climate models forecast increasingly severe regional droughts by the mid st century , results from the new study suggest that geyser eruptions could become less frequent in the future.
Indeed, periods of decreased precipitation have been shown in modern times to result in less frequent eruptions of Old Faithful , and the new research indicates that severe, long-duration droughts can terminate eruptions. For now, Old Faithful remains just that—faithful, with eruptions occurring about every 90 minutes. But this was not always the case in the past, as the new research demonstrates, and might continue to evolve in the future. But why. Volcanologists have a variety of ways of measuring present-day gas emissions from volcanoes.
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