Final Assessment

Mount Roraima is a tepui, which is a table-top shaped mountain. Tepuis form from the remains of sandstone once covered in granite, from an area between the Orinico River and the Amazon Basin. Due to the Earth's changes, tepuis abruptly rise from the giant plateau through erosion. These land formations are deemed some of the oldest in the world, resulting in surface features such as sinkholes and sometimes, caves. The climate at Mount Roraima is also very unique. Due to the location directly in the middle of a rainforest, heat from the forest rises, condenses, then cools, and creates day long rain showers and thunderstorms. Though Mount Roraima sees mass amounts of rainfall throughout the year, excess water drainage creates some of the tallest waterfalls in the world. Since Mount Roraima stands alone and is somewhat of a floating island, it is home to species that are unique to Mount Roraima and have adapted to the harsh conditions the mountain inhibits. 

A beautiful view of the Roraima Tepui, the largest of the Pakaraima mountain chain

But what about in.....10,000 years from now:

Mount Roraima is covered in joints due to the movement of plate tectonics, giving weathering a head start as these foster the movement of decayed material on the large rock. There are two types of weathering that this landform is exposed to: mechanical and chemical. Physically (mechanically) speaking, pressure release processes could very well be exhibited in this area as time goes on due to the massive amount of both sandstone and granite that the rock contains. With this happening, smaller tepuis could pop off and form around the larger mountain when under pressure. Though this type of weathering and its effects are possible, chemical weathering is by far the biggest threat to Mount Roraima due to the extraordinarily high amounts of rainfall. Rain absorbs sulfuric and carbonic acid from the surrounding atmosphere and although the levels can be weak, the amount of rain Mount Roraima sees is unusually high, as well as constant, resulting in more acidic exposure to the rock. Over long periods of time, rain can change the shape and mineral makeup of rock formations, as well as create more drastic surface features. 

Joints are spaced fissures in rocks that allow different types of weathering to occur

....in 1,000,000 years from now:

The levels of sulfuric and carbonic acid in rain are going to get increasingly higher as time goes on due to the ever-rising amount of pollution and negligence of said problem (hopefully this disaster can be avoided, as it would effect much more than just this very landscape). If this does happen, however, Mount Roraima would heavily reap the effects as not only the hydrology of the landscape would be full of chemicals as it repeats the cycle through the convection process, but its entire zoology of endemic species would become extinct.

....in 100,000,000 years from now:

Rain erosion is also a huge threat to Mount Roraima. By this point in time, Mount Roraima could very well be much smaller in size (in both perimeter and height), as the excess of rainwater falling over the top of the tepui would continually erode the side of the mountains. Though there are already heavily indented joints where waterfalls gather, these will become much deeper and wider, eroding much of the minerals and bringing them down to the base of the mountain. At the base, mass amounts of ground water would be collapsing and causing much larger and deeper sinkholes. Much of the landscapes unique design and shape would be deteriorated and hikers ability to scale the mountain may be no longer. Quartz, another mineral present in Mount Roraima's landscape as well as the most stable, is the last to crystallize and will likely be the last mineral holding up the massive tepui.

Excess rainwater falling down the tepui side in waterfalls. This image will look much different in millions of years to come. 

Though Mount Roraima's beautiful landscape is unique to this area, it is not a landform that will last through time due to its extreme climate. If the rainfall levels were not as high, I surmise that Mount Roraima would remain in amazing condition due to the lack of human intercept. But, its harsh climate will be the beautiful areas drastic downfall. 

http://www.montessoritraining.net/elementary_program2/courses/physical_geography/sample_lessons.pdf
http://www.beyondnootka.com/articles/roraima.html
http://www.bestepics.com/photo/5419.aspx

Weather Patterns

To branch off of Mount Roraima's hydrologic cycle, Mount Roraima has an extremely unique and quickly changing weather pattern due to two factors: its 1) mass and 2) surroundings. I will be primarily focusing on the impact of the tepui's surroundings which create its fickle weather.

The mountain is so massive that it creates its own weather

The climate in this region is constantly hot and humid. The average temperature is 97 degrees Fahrenheit (36 degrees Celsius), but thanks to the Environmental Lapse Rate, the temperature drops dramatically due to the high altitude and falls around 50 degrees Fahrenheit (10 degrees Celsius) at the top of the mountain, night or day. Also once at the top, it is windy and more often than not, raining. (Since there is such extreme wind and rain at the "peak" of the tepui, this is the most acclaimed reason why the top does not complete itself and is in the form of a plateau).

The rain, which varies between 1500 and 1750mm annually, is usually accompanied by thunderstorms. Even in the dry season (a mere three months out of the year), the weather being clear at the top of the tepui is very seldom, hence why this landform is known as one of the wettest places on Earth. There is a saying about Mount Roraima's weather pattern: "If you can see the mountain, it is going to rain. If you can't see the mountain, it is already raining!" 

In the middle of a rainfall, wrapped in dense fog at the top of Mount Roraima

This peculiar weather pattern, though odd, is a daily occurrence for Mount Roraima due to its surroundings. Since the landform is guarded by such a thick rainforest, the extreme tropical heat causes the moisture and humidity in the rainforest to rise, then condense over the mountain. And, since warm air can hold more water vapor, the condensed moisture turns into heavy rain clouds. This process is known as convection. The rain then creates long morning and afternoon thunderstorms, often resulting in flash flooding. 

A typical view of Mount Roraima in the morning hours

The calm after the storm at the summit of Mount Roraima, showing some radiation fogging

Helpful hint to hikers: the best season to climb this ever-popular spot is between July and January. Although it will still be extremely wet, 50% of the annual rain Mount Roraima receives is between April through September, so it is important to dodge the rainy season. Also, it is against national park policies to leave after 2 p.m., again, due to large chance of rain. 



http://dinets.info/roraima.htm
http://www.summitpost.org/monte-roraima/151790
http://www.tourismontheedge.com/best-of/mount-roraima-a-mystified-hiking-experience.html
http://www.vacationideas.me/south-america/mount-roraima-guyana-venezuela-brazil/
http://www.biosferabrasil.com/download/guide%20-%20Roraima.pdf

Hydrologic Cycle

After discussing the formation and origin of the fabled and "lost world" of Mount Roraima, it is important to talk about the unique and ever-changing climate at the tallest tepui of the Pakaraima mountain chain, as well as its effect on the hydrologic cycle of its environment.

Mount Roraima is a very unique part of our world and is mesmerized upon by many for its extremely high mesa cliffs, blackened and sculpted by wind and rain that expose its white and pink quartz crystals. The mountain is also surrounded by a lush rainforest that is endemic to many species of flora and fauna. However, its most gazed-upon characteristic is that it is home to some of the tallest waterfalls in the entire world, rightly named Roraima Falls. 

The climate at Mount Roraima is fickle, but more often than not, the regions atmosphere is home to very moist air from the rainforest. Then, combined with the warm, tropical climate, heavy rain clouds are created and spread all across the summit of the tepui chain, causing frequent downpours and rain showers. 

Moist rain clouds billowing across the mountain chain

Due to the nearly daily rain that the mountain receives, millions of liters of rainwater are drained due to overland flow. This not only makes the soil and vegetation at the top of the cliff extremely bleak, but it weathers the cliffs sides to form torrents for said waterfalls that take a descent down 400 meters worth of cliff. 

(Side note: Since Mount Roraima is very little disturbed by human kind, this weathering is the only type of weathering the mountain sees -- and hopefully will keep the beautiful area preserved for longer!)

Rainwater sweeping down the side of Mount Roraima's tall cliffs

A closer view of the tepuis process of draining rainwater

At the bottom of the cliff, sinkholes, rivers, and small pools are formed from groundwater. 

Pools of groundwater are a popular spot for visitors, hikers, and backpackers

http://www.worldtoptop.com/roraima-falls/

http://wikitravel.org/en/Mount_Roraima

http://www.geographical.co.uk/Magazine/Guiana_-_Nov_08.html

http://www.summitpost.org/roraima-s-venezuelan-side/96693

Formation of Mount Roraima

For my second blog post, I wanted to briefly touch on the origins and basis of the beautiful landform of Mount Roraima: its formation. 

At one point in time, this area was one gigantic landmass. Eventually, however, the South American and Caribbean tectonic plates collided with one another, breaking up the massive landmass into hundreds of flat-topped mountains, or tepuis, meaning "house of spirits". Thus lifting Mount Roraima, the largest of these tepuis, above land.

Chain of tepuis forced upward by tectonic plates in Pakaraima mountains

Though the collision of tectonic plates causes uplifting of breath-taking landforms, its collision creates other consequences as well. One of the most dramatic consequences of this includes huge sinkholes at the summit of these mountains. In fact, one of the plateaus in the Pakaraima mountain chain has a sinkhole that is almost 1,000 feet deep! 

El Foso, a 300 meter-deep sinkhole at the summit of Mount Roraima shows a more dramatic effect of Earth's plates motion caused by tectonic plate collision

A less dramatic effect of plate collision, visitors and hikers will enjoy the natural jacuzzis Mount Roraima provides

The location of these beautiful tepuis creates isolation. With that being said, geologists have tested the molten rocks that have crept its way up between the layers of sandstone after said tectonic collision to date their origins. They have concluded the sandstone to be at least 1.8 billion years old, thus making this mountain chain to be one of the oldest land formations on Earth. 

Fun fact: Since there are no natural predators or human life atop the large mountain, 30% of all animal and plant species that reside in this area are unique to Mount Roraima, including mosses, flowers, and insects. They have adapted to the harsh conditions the mountains inhibit and cannot be found anywhere else in the entire world! 

Tiny frog endemic to Mount Roraima

http://www.beyondnootka.com/articles/roraima.html
http://www.theorangemango.com/the-lost-world-mount-roraima/
http://books.google.com/books?id=J5F4AgAAQBAJ&pg=PA26&lpg=PA26&dq=mount+roraima+tectonic+plates&source=bl&ots=2nBm3Or0q8&sig=TeADmJfDLTuBtHyGCP4HLdOqy3M&hl=en&sa=X&ei=Ei4TVN_vBNH5yQSY4IK4Dw&ved=0CD8Q6AEwCQ#v=onepage&q=mount%20roraima%20tectonic%20plates&f=false

Introductory Post

Good afternoon! My name is Andrea Petrucelli. I am 21 years old, and I am a Music Business major at University of Colorado Denver. I graduate in the Spring, and could not be more excited about what the world has to offer me. 

For my Introduction to Physical Geography blog, I chose a place that has always been of interest to me since I saw the Disney/Pixar movie, "Up". That place is Mount Roraima. 

A still shot from the Disney/Pixar movie, "Up", of what they call "Paradise Falls"

Though Paradise Falls, the fictional mystery land depicted in "Up" is not a real place, its geography is based off of the highest of the Pakaraima mountain chain in South America, Mount Roraima. Characterized by a 2,700-meter tall mountain, surrounded by 400-meter long cliffs, residing some of the highest waterfalls in the world, and what are thought to be some of the oldest formations on Earth, Mount Roraima is an astonishing piece of our Earth and touches the borders of three countries: Brazil, Guyana, and Venezuela.

Angel Falls, Venezuela is home to the highest waterfalls in the world

Mount Roraima as the moisture from the forest and ocean condenses into clouds and mist and scales the mountainside

Disney depicted this fictional place to be absolutely stunning, so to find out it was based on a real place was even better! The ever-changing weather and basic shape of the landform are intriguing to me, and I am very much looking forward into researching more in-depth about the land formations, surrounding forest, and the weathering of such a massive geographical formation. 

http://all-that-is-interesting.com/post/6485769653/the-mind-blowing-mount-roraima

http://science4grownups.com/archives/2009/05/29/general/the-real-world-behind-ups-paradise-falls-530

http://www.tourismontheedge.com/best-of/mount-roraima-a-mystified-hiking-experience.html