Tuesday, January 10, 2017

Mount Washington During Autumn


A spontaneous mid-semester trip in October to the granite state proved to be a great way to recharge from graduate school and to visit one of the most rugged and alluring areas in the east. We originally set out to attempt the challenging bucket-list "Presidential Traverse" hike that includes ~10 peaks above 4,000' in elevation, and makes up part of the presidential range including Mt. Washington - the second highest peak (6,289') in eastern North America (second to Mount Mitchell). Mount Washington not only draws adventurists from afar with its vista views, but also with unpredictable weather that makes hikes challenging and refreshing year round.

The highest surface wind ever recorded by man (231 mph) was observed on its summit in 1934 when the anemometer broke, which is in part why it was designated as having "the worst weather in America," and the cause of nearly 150 deaths since records began in the mid 19th century. There are plenty of taller mountains in North America, so what makes Mount Washington uniquely dangerous? It really boils down to its geography  in relation to weather patterns. The highly erosion-resistant geology of the white mountains shoots up high above the glacially leveled surrounding area to the west, where the summit of Mount Washington interacts with arctic air from the North American jet stream. The mountain range creates a funnel from the southwest to northeast that channels and accelerates air and virtually any storm system emerging from the west. To make matters worse, the North American jet stream often converges near Mount Washington with warmer systems moving along the cost to provide dangerous and unpredictable extreme weather conditions year round. Sign me up!

During this trip, we traveled southbound and only made it to Mount Washington, but we miraculously drove 1700 miles and hiked 12 miles in 39 hours - we live for short, cheap, refreshing trips like this. The photo below shows our route, which began at the Great Gulf Wilderness trailhead parking lot. Even in October, it was below freezing above tree-line, which made the stop at the Mount Washington Observatory for chilly and cornbread that much better!

The Presidential Range is part of the White Mountains, which makes up one-quarter of New Hampshire's land mass. Some states are ironically named after an unnatural occurrence. For example, Maine is "the pine tree state" even though old growth forests such as Big Reed suggest pines were historically a small component of forests during pre-settlement (on a human timescale) compared to other species. Though, New Hampshire was aptly named the granite state in large part due to granite bedrock commonly found in the white mountains, particularly Osceola (green) and Conway (Pink) stone. 

The white mountains have a long, complex history that can be traced back to half a billion years ago. Since then, a complex combination of processes over space and time helped form the White Mountains. Specifically, the Appalachian orogenies from the creation of Pangea, the White Mountain Batholith of volcanoes formed from the rifting of Pangea, and glaciation and weathering has shaped and greatly defined the region's geomorphology. First, the convergence of Gondwana and Laurentia  to help form Pangea paved way for the Appalachian Orogeny (Taconic, Alleghenian, and Acadian orogenies) to form the Appalachian Mountains. Roughly 200 million years ago, the Pangea rift began to push the North American Plate westward forming the Atlantic ocean, and the movement of New Hampshire over the New England Hotspot between 100 and 120 million years ago caused large volcanoes to create much of the White Mountains, and later formed the New England Seamount Chain. Since then, there have been two large glaciation stages (Illinoian and Wisconsinan) of the Laurentian Ice Sheet that left a great impact on North America. Today, we see evidence of all these processes in the form of folded rock outcrops, large cliffs such as Franconia Ridge and Cathedral Ledge that are cooled magma chambers, glacial erratics such as Boise Rock, glacial grooves, and large cirques such as Tuckerman's Ravine that once housed receding glaciers. To me, the White Mountains represent a beautifully unforgiving, harsh place filled with evidence from the past that is present everywhere you look if you have an eye for it. 


With such steep environmental gradients, change in vegetation also exists rather abruptly from trailhead to summit. At the base of this range, large sugar maples, yellow birches, and other deciduous trees line the path and creeks. It isn't long until spruce and hemlock take over before giving way to the flagging, stunted trees (krummholz) and eventually the low-growing alpine /subalpine vegetation that dominates the rocky outcrops, balds, and alpine meadows above tree-line. This contrast is partly what brings me to the area, where forests turn into a quilt of sedges, rushes, grasses, lichens, mosses, and mat-forming shrubs. In fact, over 60% of all plant species in the Presidential Range are restricted to above the tree-line, including some species that are endemic to northeastern US alpine region such as Boot's rattlesnake root (Prenanthes boottii), and Robbin's cinquefoil (Potentilla robbinsiana) - a species endemic only to the White Mountains. High winds, a short growing season, low temperatures, heavy cloud and fog cover, high precipitation, and well-drained soils with low nutrient availability and high organic matter content all provide adequate conditions to make the White Mountains a great place for high alpine and subalpine biodiversity. Another important factor that dictates vegetation composition and structure in the White Mountains is snow accumulation, which is influenced by a host of landscape attributes such as slope and aspect. Even to native New Englanders like myself, it always feels like the short distance from base to summit is hundreds of miles with the abundance of disjunct vegetation. 





























Mount Washington and the rest of the White Mountains will always have a special place in my heart, not only because I am a native New Englander, but also because of the vast display of changes in landform, geology, weather, and vegetation in such a short distance. It is really an environmental scientist's classroom. Not-to-mention, the surrounding town of North Conway isn't so bad either, with fresh lobster rolls, great local breweries, and rich culture and history in every nook. I could only imagine what this place would look like in winter . . .

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