Tuesday, May 3, 2011

the Amazon River

Peru is host to one of the largest fresh water rivers. The Amazon river is located in the northern part of South America; stretches from the east to west. It supplies 1/5 of earth’s fresh water. The Amazon is a suspended bed load river that transports sediments along the bed of the river by sliding and rolling. 
small debris tumbling along the bed load


The Amazon is a Perennial river which means it flows year round.The rain, flooding of tribute rivers, and snow melting in the mountains supply the rivers water. 
Rainfall over the Amazon

The Amazon is a single channeled river with wiggles across its floodplains. The wiggles are formed when there is a deposition at point bars and cut banks are eroded by high velocity water flows.
Sediments make the water look dirty and muddy

Sometimes high velocities can cause a river to flood and create levees. If the levee does not reconnect with river and turns into a mini-lake it’s called an oxbow. Strangely enough, the Amazon maybe a big river but it carries small particles and it rarely over floods. 

cut banks being formed by erosion and deposition, an oxbow formed from a previous flood

The Amazon River maybe a large fresh water supplier, but its water is drinkable only after proper treatment. People get sick and often die when the river water is not properly treated. The Amazon River does not over flood often, but when it does, cut banks erode and collapse. People who build their houses on the cut banks lose their homes. 

house sitting on a cut bank next to a river

Wednesday, April 6, 2011

Peru blog # 3

(Peru's high and low elevations)
Peru has an exotic mixture of climates. In the Andean Mountains there is a high amount of moistures and pressure changes (mT). On the coastal side there is a dryer climate (cT). 
(el nino ENSO)
(Humboldt currents)
Peru has pressure changes in winds due to the Humboldt currents. The Humboldt is a cold ocean current that flows north along the Pacific Coast of South America before turning west. Its drift is what causes the Peruvian coast to have a desert.  More dangerously Peru has a visitor every 7 years around Christmas time. El Nino Southern Oscillation (ENSO) is a see-saw pattern of reversing surface air pressure between the eastern and western tropical Pacific. ENSO is a global phenomenon that affects global climate like sea surface temperatures which tend to change the regions climate.
(maritime Tropic mT on the equatorial)

In the Andean Mountains there is an unstable cooling. Adiabatic process occurs when temperature changes due to pressure change, causing Peru to have a warm & wet climate.  These changes classify Peru as a maritime Tropic (mT). Air mass is classified by the horizontally uniform levels of temperature, humidity, and pressure. 

(morning advection fog in Cusco Peru)

(Peru shortly after a sandstorm aka: haboob)
If one ever visits the tropic side of Peru one will run into advection fog caused by cold currents. If one ever visits the coastal side of Peru one might get stuck in a sandstorm called haboobs.

Wind currents can alter geography climates that can potentially create chaos. Unfortunately for Peruvians when ENSO comes around it can cause deaths, floods, and droughts. Sandstorms as minor as they may look they can cause significant damage too. It all affects the Peruvian population in one way or another; whether it’s a death or a dry season with no crops.
(some cumulus & strato-cumulus hubbering over Machu Picchu)

Thursday, March 3, 2011

Peru's mass wasting

Peru’s exotic mountains and valleys currently continue to be victims of mass wasting. Mass wasting is the down sloping movement of rocks caused by gravity. This process helps eroding material get from high elevations to low elevations. Although erosion may not sound complex or harmful, it has created fear in Peruvian civilians. Peruvians has been victims to landslides and avalanches due to earthquakes.
Process's of mass wasting

Landslides are when mass movements of rocks, debris, and soil travel down a slope taking weak lose objects in its way. Even though landslides occur as a natural environmental hazard, recent activities have been due to human activity.
mud landsliding occurring
Avalanches can occur under different circumstances. The most common way is through vibrations or silent movements like echoes. They also occur when it rains or snow starts to melt. The liquid starts to roll down the slope causing it to bring down small portions of snow that turn into avalanches.   

In conclusion to mass wasting, it is most unfortunate to see the environments natural occurrences create fatal consequences. It is especially sad to see how some people can be left without a home in a matter of seconds. In Peru mass wasting continues to conquer small villages and towns near the Andean mountain range.  
home eroded by landslides

Monday, February 14, 2011

Peru's Ubinas Volcano

Peru is one of the hosts for the Andes Mountain Range. The Andes are a Mesozoic-Tertiary orogenic belt formed along the Pacific Ring of Fire, formed during the Cretaceous period about 138 million years ago to 65 million years ago.  The Andes were caused by the subduction of the oceans crust beneath the Southern American plate.  

The Pacific Ring of Fire is an area where a number of earthquakes and volcanic activity goes on. The Ubinas volcano is one of the most active volcanoes located in this area (Peru).  The most recent eruption was in 2010 and continues to create disruptions.  Ubinas is a strato-volcano also known as a composite volcano with a summit elevation of 18,609 ft. Ubines has a 1.4-km-wide caldera cut. 

A strato or composite volcano is a tall conical volcano, made up of my strata layers of harden lava and other rock fragments.  A caldera is a large chunk that collapses back in the volcano when an eruption occurs. 
Ubinas active eruptions have left the area bare of no trees, no plants and no wild life. In some cases the hazardous chemicals released by the volcano has caused savior illnesses upon nearby residents.