Peru is a country of varied climate because the influence of the following phenomena:
To visualize Peru geography, imagine a sheet of paper crumpled lengthwise down the middle from top to bottom, smooth on both sides.
That might describe basic Peru geography.
a flat sheet of paper, many milenia ago, the land forming
the current geography
of Peru apparently had been a vast plain. Then, geological forces compressing the two sides towards the middle produced the upward crumpling of the central spine.
These geological processes resulted in what is called the Cordillera of the Andes, that central spinal column that runs down the middle of the Andean countries from north to south.
This central spine of mountain highland separates the two flat areas of Peru geography: the coastal zone to the west and the jungle zone to the east.
These three regions or zones with their distinctive and varied altitudes and climates provide a key to the identity of Peru as a whole as well as the challenges presented to living in such a highly complex and varied territory.
To get an idea of the size of Peru, we can say that
The Andean mountain range
defines the three macro regions that make up the geography
of Peru: the coast, the moutains, and the jungle. Although
this classification is somewhat simplified, it actually gives us a very
clear overall idea of what makes up Peru geography.
The sector of Peru geography referred to as the coast, or "la costa" is
a strip of desert consisting
of rolling plains that runs parallel to the coast
of Peru from Tumbes in the very north to Tacna in the extreme south.
The width of the Peruvian coastal region is generally narrow but does vary, reaching its widest point in the northern department (province) of Piura in the desert of Sechura. At that point it is 180 km (112 miles) wide.
Its narrowest point is located in southern Peru in the department (province) of Arequipa, where the coast practically disappears into rocky cliffs or escarpments that are actually what remains of an ancient coastal mountain range.
At the point of the coastal city of Lima, Peru's capital, the Peruvian desert has an average width of only 15 km (9.3 miles).
The central of the three
which make up the geography of Peru is the sierra (mountains) formed by
the rugged heights of the Andes mountain range.
These mountains are actually three parallel mountain chains in the north and middle of Peru, tapering to two parallel chains in the southern part.
The three northern Andes chains join the three chains of mid Peru geography at El Nudo de Pasco and these go on to join the mountain chains of the south at El Nudo de Vilcanota.
In spite of the common characteristics of the central strip, ie, high mountains and deep valleys, not all these mountainous areas are the same.
The northern Andes are lower and wetter than the mountains farther south. This has enabled some of the moisture and vegetation of the northern forest to reach to the coast.
Also, in the northern Andes you find the lowest point of the entire Andean Cordillera or range: the Abra de Porculla is a pass of 2145 meters (7,037 feet) altitude that allows relatively easy access to the jungle side of the mountains.
The central Andes are the highest and steepest and that makes the central mountain region a place of difficult access. The only real reason for routes across the Andes in this challenging area is its proximity to the dynamic capital city of Lima, Peru.
The southern Andes are thicker than the northern and central Andes; a cross section of the moutains going from Arequipa to the border with Bolivia shows a distance of over 500 km. (311 miles) in width at high altitudes in excess of 4,000 m (13,000 feet).
It is in the valleys of this thick strip of southern mountains that the largest concentrations of remnants of ancient people and cultures is found. Some of the most important cities or centers of ancient cultures of Peru in this area are Ayacucho and Cusco among others.
The third region is the
(la selva) to the east of the mountains, also referred to
the oriente (east). Like the coast and mountains, the jungle also has
its share of variety.
If the Peruvian jungle had to be divided into just two sub regions, these two would most like be from north to south, also, based on the difference between the highland forest and lowland forest.
The high rain forest or cloud forest is found on the eastern slopes of the Andes from 1000 meters (3, 280 feet) on up, where the very warm conditions give it a characteristic appearance: very wet, rainy, cloudy and with an average temperature between 25 degrees to 30 degrees Centigrade (degrees Fahrenheit).
The jungle forest, on the contrary, is flat, is surprisingly almost at sea level, and is the warmest region in Peru, with high temperatures usually above 35 degrees Celsius (95 degrees Fahrenheit).
Much of this forest floor is flooded, especially in areas where two or more rivers come together.
There is generally a cycle of heavy rains/dry season, rivers overflowing/dropping. This constant change impedes year around cultivation in many areas and favors the development of activities related to fishing and harvesting of wild fruits.