Distinctly Montana Magazine

69 w w w. d i s t i n c t l y m o n t a n a . c o m Classified as a Volcanic Explosivity Index (VEI) 7 event, based on the estimated volume of material that it ejected, Tambora's caldera-forming eruption may have been the most powerful ex- plosion on Earth during the last 12,000 years. It exacerbated the cooling trend initiated by preceding eruptions and, according to Gillen D'Arcy Wood, contributed to an "overall decline of global average temperatures of 1.5°F across the entire decade." Conse- quently, Wood characterizes the havoc that Tambora wreaked as "the most catastrophic, sustained weather crisis of the millenni- um." Historian John Post echoed those sentiments, when he de- scribed Tambora's aftermath as "the last great subsistence crisis in the western world." Instrumental and observational data recorded contemporane- ously by Luke Howard, the English "father of meteorology," cor- roborate these conclusions. Daily temperatures in London from 1807-1815 averaged 50°F, a baseline already suppressed by sev- eral years of volcanic weather. That figure plummeted to 38°F in 1816, the "Year without a Summer," which New Englanders also described as "Eighteen-Hundred-and-Froze-to-Death." Shortly after Tambora-induced cooling finally dissipated, major erup- tions of Zavaritskii (Kuril Islands) and Cosigüina (Nicaragua) in 1831 and 1835, respectively, reactivated atmospheric cooling. For peoples indigenous to Montana, the Neo-Boreal period co- incided with the zenith of communal bison hunting, a practice initially pursued through the antecedent use of buffalo jumps. The era (1770-1850) that Pederson identifies as the climax of the LIA can be described, with equal justification, as the golden age of Plains Indians. Then sufficiently mounted, they harvested their staff of life more efficiently and could fully commit to bi- son-based, equestrian nomadism. The modest increase in annual precipitation that occurred on the northwestern plains may not have been enough to maximize bison carrying capacity. However, environmental historian Dan Flores provides a superb 30,000-foot perspective that illustrates the convergence of factors which contributed collectively to the Serengeti-like landscape that Lewis and Clark witnessed. LIA conditions promoted the growth of C4 grasses, such as buffalo grass and grama grasses, which bison preferentially consume, instead of cool-season grasses. An almost mythical biomass of bison accrued at the same time that virgin-soil epidemics, intro- duced by the first waves of European colonialism, decimated trib- al populations and reduced hunting pressures throughout much of the contiguous United States. As Flores (2016) observes, the herds eventually spilled "out of the Great Plains, both eastward across the Mississippi and westward down the Columbia and Snake River systems," from which they "squeezed like tooth- paste into every nook-and-cranny prairie from Pennsylvania to Georgia, and across Oregon, Idaho and northern Utah." When the Corps of Discovery later made their epic journey, the effect of buffer zones on game populations slowly became evident. William Clark noticed that wildlife invariably was most 40 Spanish Peak Dr. | Bozeman | 406.582.8700 | blacktimberfurniture.com ReclAim YouR spAce DESIGNED AND HAND CRAFTED IN THE GALLATIN VALLEY BY TODD FULLERTON AND HIS TEAM FOR YOUR MONTANA LIFESTYLE WITH A CUSTOM MURPHY BED 2022-24 of B E S T M O N TA N A A S V O T E D B Y R E A D E R S O F Y E A R S WO N W I N N E R !

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