Over the Pass

A pass is a route over a mountain range.

The route of a mountain pass typically takes advantage of a low point in a ridge called a topographic saddle.

Saddle point (red dot)

A topographic saddle is analogous to a saddle point in mathematics.

A saddle point, indicated by a red dot (right), marks the lowest point along a ridge that also represents the highpoint between two valleys.

Finding passage through a mountain range is often a matter of locating a saddle. A saddle is also known as a gap, a notch, or a col.

Arthur Cayley advanced a theory of continuous surfaces in 1859 which is the mathematical foundation for contemporary topographic maps. Cayley proposed contour lines connecting points of constant elevation and slope lines perpendicular to the contour lines. Such maps assist hikers planning a route through mountainous terrain.

Over every mountain there is a path, although it may not be seen from the valley.
— Theodore Roethke

View below the Beartooth Pass, 19 September 2014

Historically mountain ranges have been formidable barriers to human travel. Mountain passes have played a role in migration, trade, and battle. Khyber Pass is part of the ancient Silk Road which has been a trade route between Central and South Asia for centuries.

Notable Mountain Passes

Thorung La	17,769 ft	Through the Damodar Himal, north of the Annapurna Himal, in central Nepal.
Beartooth	10,947 ft	Through the Beartooth Moutains on the border of Montana and Wyoming.
Donner	7,056 ft	Through the northern Sierra Nevada, above Donner Lake.
Brenner	4,495 ft	Through the Alps along the border between Italy and Austria.
Khyber	3,510 ft	Part of the Silk Road connecting Afghanistan, Pakistan and India through the northeastern part of the Safēd Kōh mountains.

It is not the mountain we conquer but ourselves.
— Edmund Hillary

REFERENCES

• Geographic Information Science and Mountain Geomorphology, edited by Michael Bishop, John F. Shroder, Springer 2004.
• Mountain Pass, Wikipedia.

Nature Beckons

Paul Hawken's commencement address to the University of Portland class of 2009 is a call to action:

You are going to have to figure out what it means to be a human being on earth at a time when every living system is declining, and the rate of decline is accelerating. Kind of a mind-boggling situation... but not one peer-reviewed paper published in the last thirty years can refute that statement. Basically, civilization needs a new operating system, you are the programmers, and we need it within a few decades.

— Excerpt from Paul Hawken's commencement address.

Civilization's operating system, seized up by superstition, fear, ignorance and tribalism, seems destined to a harrowing ride toward extinction.

While there might not be subsistence-wage jobs for graduates, there is perhaps an existential mission. Hawken's speech is titled,

You are Brilliant, and the Earth is Hiring

The plea to reboot comes from the motherboard of rational thinking, self-awareness, and introspection.

Hawken's message is inspired by the sublimities that surround us:

Ralph Waldo Emerson once asked what we would do if the stars only came out once every thousand years. No one would sleep that night, of course. The world would create new religions overnight. We would be ecstatic, delirious, made rapturous by the glory of God. Instead, the stars come out every night and we watch television.

— Excerpt from Paul Hawken's commencement address

Nature Beckons

Earth's abundance has obscured the realization that civilization has been motivated by self-interest and ruled by ignorance and fear. Nevertheless hope springs forth with each generation.

They got distracted and lost sight of the fact that life is a miracle every moment of your existence. Nature beckons you to be on her side. You couldn’t ask for a better boss. The most unrealistic person in the world is the cynic, not the dreamer. Hope only makes sense when it doesn’t make sense to be hopeful. This is your century. Take it and run as if your life depends on it.

— Closing from Paul Hawken's commencement

REFERENCES

• Commencement: Healing or Stealing? The unforgettable Commencement Address 2009, Paul Hawken, University of Portland.
• Best Environmental Commencement Speech Ever? by Paul Loeb, Huff Post Green, 2 July 2014.

Geothermal Energy

What is the origin of the heat energy erupting from Earth's surface?

Earth formed by accretion from solar nebula — an interstellar cloud of dust, hydrogen, helium and other ionized gases — about 4,540,000,000 years ago.

Extreme volcanism and collisions with other bodies made much of the nascent planet's surface molten. Volcanic gases formed a fledgling atmosphere.

Bárðarbunga Volcano, 4 September 2014

Image: Peter Hartree

As the planet cooled, it formed a solid crust. Rocks in the core and mantle remain hot from the original materials colliding at high speeds.

Terminology:
Magma refers to molten rock still underground. If molten rock erupts onto the surface, it is called lava. Lava is liquified rock at 1,292 to 2,192 °F (700 to 1,200 °C).

Bárðarbunga Volcano, 2 September 2014

Image: Arctic-Images/Corbis

Collision energy is the source of heat trapped below Earth's crust. Heat below Earth's crust is called geothermal energy.

May not subterraneous fire be considered as the great plough which Nature makes use of to turn up the bowels of the earth?
— Sir William Hamilton

REFERENCES

• 11 Photos of Iceland's Bardarbunga Volcano Erupting That Are Just Unreal, Mashable, 12 Sep 2014.
• Bárðarbunga, Wikipedia.
• How is lava formed, Oregon State University Volcano World.

Inhospitable Beauty

Acidic lakes can form in volcano craters because of volcanic gases creating a stunning, but inhospitable environment.

Never say there is nothing beautiful in the world anymore. There is always something to make you wonder in the shape of a tree, the trembling of a leaf.
— Albert Schweitzer

Kawah Ijen

The turquoise-colored lake in the crater of the Kawah Ijen volcano appears serene but the water has a prohibitively acidic pH of 0.3 because of an influx of sulfuric gas from the volcano. For comparison, the pH of pure drinking water is 7 (neutral), while the pH of lemon juice is 3.

Acidic lake in Kawah Ijen crater

The Kawah Ijen crater lake the world's largest acidic lake.

Each volcano is an independent machine—nay, each vent and monticule is for the time being engaged in its own peculiar business, cooking as it were its special dish, which in due time is to be separately served.
— Clarence Dutton

Kawah Ijen at Night

At night, a blue glow emanates from the cracks in the Kawah Ijen volcano where sulfuric gases are emitted. Sulfuric gas escapes from the subsurface under high pressure and temperatures up to 1,112°F (600°C).

Blue flame of sulfuric gases igniting in the Kawah Ijen crater.
Photograph by Oliver Gunewald

The super-heated stream of sulphuric gas ignites when exposed to atmospheric oxygen causing the intense blue flames observed at night.

At times our own light goes out and is rekindled by a spark from another person. Each of us has cause to think with deep gratitude of those who have lighted the flame within us.
— Albert Schweitzer

REFERENCES

• Ijen, Wikipedia.
• Report on the Geology of the High Plateaus of Utah, by Clarence Edward Dutton, 1880.
• Satellite Image of Kawah Ijen Volcano, NASA Earth Observatory, 22 August 2013.
• Stunning Electric-Blue Flames Erupt From Volcanoes, by Brian Clark Howard, National Geographic, 30 January 2014.
• Welcome to the largest, most highly acidic crater lake in the world, by Bec Crew, Science Alert, 10 August 2014.