American History – June 2019

(John Hannent) #1

The white-capped world into which Hazard Stevens and Phi-


lemon Beecher Van Trump clambered is disappearing. Ice


cloaked the Cascade Range long before Mount Rainier’s vol-


canic cone rose 500,000 years ago. Although Rainier remains


the most glaciated American peak outside Alaska, in the last


50 years its ice fields have shrunk at least 14 percent.


Four have disappeared.


Many scientists blame global warming. Since 1895 the


average Pacific Northwest temperature has risen 1.4° Fahren-


heit. Forecasting is difficult in regions where mountain and


ocean weather systems collide, but digital models predict that


this century will see temperatures continue to climb, with


more precipitation taking the form of rain instead of snow.


This scenario spells trouble for Rainier’s 26 named glaciers,


formed in prehistory when heavy snowpack in the high, fro-


zen reaches of the mountain compressed into slow-moving


rivers of ice. When a glacial system is in balance, each winter


new ice accumulates, keeping pace with losses incurred


through summer melting at the system’s foot. At Rainier, this


is no longer happening. Between 1970 and 2008, only two of


the peak’s glaciers gained volume. For a decade, the Nisqually


Glacier, on which Van Trump lost his climbing staff, has been


shrinking in length an average 140 feet annually. The Para-


dise-Stevens Glacier, which feeds the waterfall that raged


beside the first summiteers’ base camp, has lost well over half


of its mass and now comprises two stagnant ice fields.


Glacial melting is a part of normal climate variation;


Rainier’s glaciers have fluctuated in size for millennia. Thir-


ty-five thousand years ago, the now four-mile long Cowlitz


Glacier stretched 60 miles to the mountain’s southeast.


What’s troubling today is the speed of melting—estimated at


six times the historic rate—and the consequent dwindling of


a vital regional water source.


Ecologists and engineers cringe at the long view. As tem-


peratures rise and glaciers recede, so do the alpine and


sub-alpine habitats of signature Rainier residents like pink


mountain heather, a ground cover, and the shrill-whistling


pika, a small herbivore. Accelerated run-off is dumping dis-


proportionate amounts of debris—boulders, gravel, and silt


glaciers scraped from the mountain as they creep—into the


five major river systems that Rainier’s ice fields feed.


As a result, river beds are rising; today’s Nisqually flows


some 40 feet higher than in 1910. Other streams are rerout-


ing themselves, sometimes through trails, roads, and camp-


grounds. The National Park Service has built dikes and


levees to protect key infrastructure and the settlement


of Longmire, now 29 feet below the Nisqually. A major


flood, like one in 2006 that did $36 million in damage and


closed the park for six months, easily could overwhelm


these locales, threatening access for the 1.7 million people


lured to the park annually by Rainier’s ever-changing


charms. —Jessica Wambach Brown


83 Years’ Difference


A 1934 photo of Paradise Valley and


Stevens glaciers, top, contrasts with


the bare rock visible in 2017.


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JUNE 2019 49


Melting Away

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