Creation of glacial landscape:
The
Himalayas were formed through convergent processes. During the collision of the
Eurasian and Indian plates, the large mountain range was formed over millions
of years. The Himalayas are among the youngest mountain ranges on the planet
and are growing at approximately 5 mm per year.
Glacial
ice is formed due to the compaction of snow and ice over time; where
accumulation exceeds ablation. Alpine glaciers surrounding the Mount Everest
region of the Himalayas are all currently in a state of retreat. The Rongbuck
glacier, draining the north side of Mount Everest into Tibet, has been
retreating 20 meters per year.
The Himalayas in 1,000 years from now:
An earthquake is
likely to occur in the Himalayas near the border of Nepal in 1,000 years from
now. Being that the mountains are atop the Eurasian and Indian tectonic plates,
the convergence of the continental plates will likely cause a sudden release of
energy. The plates shift several millimeters each year. These yearly shifts
cause an estimated 140 earthquakes annually. Not only are earthquakes going to
occur, the Himalayan Mountains will continue to rise as well. In China, the
current elevation of the Himalayan Mountains is between 4,000-45,900 meters and
is estimated to be growing 5 millimeters annually. In 1,000 years from now, the
Himalayas will have grown roughly 5 meters, increasing the elevation to
4,005-45,905 meters.
Glacial landscape of the Himalayas in 10,000 years:
Earth has been in an ice age for the last 2.5 millions
years. Since then, the world has seen cycles of glaciation with ice sheets
advancing and retreating in 40,000 and 100,000-year intervals. Earth is currently in an interglacial
period and had its last glacial period was roughly 10,000 years ago. Arguably,
Earth will likely experience a period of glaciation in another 30,000 – 100,000
years. Until then, Earth will probably remain in its interglacial period with
warmer temperatures and receding glaciers. It’s likely that the Rongbuk glacier
will retreat roughly 200,000 meters in 10,000 years.
Rongbuck glacier in 1921: Notice the downward movement of the glacier due to the slope. Notice also the formation of a lateral (or medial) moraine. There also looks to be one cirque in this photo. (Retrieved from: http://www.glacierworks.org/glacier/main-rongbuk-glacier/)
Rongbuck glacier in 2007: Notice the glacier has retreated. There also looks to be a knife-like ridge, or an arête, on the right. The cupping of the snow is due to sublimation. (Retrieved from: http://www.glacierworks.org/glacier/main-rongbuk-glacier/)
The Himalayas in 1,000,000 years:
In 1 million years, assuming Earth is still in an
ice age since glacial ages come about every 250 million years, the face of the
Himalayas will look quite different from today. Glaciers will advance and
retreat about 10 times (100,000 x 10) and will be retreating in 1,000,000
years. As glaciers retreat, they leave behind till and other depositional
landforms. There will likely be more extensive lateral moraines, which are
mounds of till that collect on valley sides due to rock falls and plucking of
valley walls. Glacial lakes may form, since near the end of the last glacial
period about 10,000 years ago, the retreating glaciers often left behind large
deposits of ice, melting and creating tarns. Flora and fauna will likely
advance further into U-shaped valleys as well.
Notice the medial moraine development in the lower photo. Notice also the tarn in the upper photo. The comparison of both photos shows Rongbuk glacier in a state of retreat.
(Retrieved from: http://www.markhorrell.com/blog/wp-content/uploads/comparison_2009.jpg)
Conclusion:
Overall, the Himalayas will likely change over the
next thousand, ten thousand and one million years in the future. Different
processes, such as plate convergence, will create earthquakes and new
mountains. Depositional, as well as erotional, landforms will be created due to
receding glaciers, changing the face of the Himalayan landscape.
References:
