The Climate of the Sumatra Rainforest

Sumatra is an island of Indonesia. The climate is unique with monsoon circulation and other weather phenomenas.

Zachary Luna

The Sumatra rainforest takes up 2.5 million hectares of land on the island according to UNESCO. It is considered one of the largest conservation areas in Southeast Asia. The unique climate of Sumatra allows it to have exceptional biodiversity. Image above by whereandwhen.net

The equator goes directly through the center of Sumatra. This in one of the factors that results in year round warm temperatures and high levels of precipitation. However, due to Sumatra being located on the equator, day length is approximately 12 hours with very small fluctuations throughout the year. The longest day is actually only 6 minutes more than the shortest day of the year. Image by lonelyplanet.com.

This image shows a map of the incoming solar radiation for all of Indonesia. Solar radiation for Sumatra is substantial. The annual incoming solar radiation ranges anywhere from 1600-1800 kWh/m^2 according to Hafizh (2016). The Sumatra rain forest has a low albedo due to the canopy of the forest covering most of the land surface (Poussart et al 2004). The dark shades of the forest allow for incoming solar radiation to be absorbed rather than reflected. Image by Hafizh (2016).

Sumatra has many mountains with an average elevation of 1,500 meters above sea level according to UNESCO (2004). There is little to no snow present ever on any mountains in Sumatra. The high mountains are able to trap moisture and even make the atmosphere unstable which leads to a squall line. Image by Stefanie Weijsters.

Monsoon circulation on the island can cause weather phenomena such as squall lines. These squall lines can cause heavy rainfall, large hail and intense winds according to Lo et al (2016). During the monsoon season, southwest winds pass over the mountains. This results in mountain waves that cause the surrounding atmosphere to become unstable. This results in thunderstorms. The thunderstorms begin to merge into each other and create a squall line according to Lo et al (2016). Image by Fred Roswold.

The image above shows the Malayan tapir. One of the unique species that lives on the island of Sumatra. Sumatra’s unique climate is able to house 10,000 plant species, 201 mammal species and 580 bird species (UNESCO 2004). Over 60 of these species are endemic, meaning they are only found on the island of Sumatra. Image by Daniel Sendecki.

Overall, Sumatra is a valuable ecosystem with a very special climate. It has warm temperatures and high precipitation caused by monsoon circulation. The monsoon circulation and terrain of the island result in interesting weather phenomenas such as squall lines. The region being on the equator also contributes to this along with low day length variability. Its climate is able to house species that are not found anywhere else on the planet. The island has exceptional biodiversity and needs to continue to be a focus for conservation. Lots of new, unknown information can be acquired from this vast region.

References:

Lo, J. C.-F., and T. Orton. 2016. The general features of tropical Sumatra Squalls. Weather 71:175–178.

Poussart, P. F., M. N. Evans, and D. P. Schrag. 2004. Resolving seasonality in tropical trees: multi-decade, high-resolution oxygen and carbon isotope records from Indonesia and Thailand. Earth and Planetary Science Letters 218:301–316.

Centre, U. N. E. S. C. O. W. H. (n.d.). Tropical Rainforest Heritage of Sumatra. https://whc.unesco.org/en/list/1167/.

Hafizh, H. 2016. Performance Analysis of Solar Updraft Power Generator in Indonesia. KnE Engineering 1.

University of Illinois Urbana-Champaign: DAS, 2010. Squall Lines. Ww2010.atmos.uiuc.edu,.  http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/svr/modl/line/squall.rxml .

The equator goes directly through the center of Sumatra. This in one of the factors that results in year round warm temperatures and high levels of precipitation. However, due to Sumatra being located on the equator, day length is approximately 12 hours with very small fluctuations throughout the year. The longest day is actually only 6 minutes more than the shortest day of the year. Image by lonelyplanet.com.

This image shows a map of the incoming solar radiation for all of Indonesia. Solar radiation for Sumatra is substantial. The annual incoming solar radiation ranges anywhere from 1600-1800 kWh/m^2 according to Hafizh (2016). The Sumatra rain forest has a low albedo due to the canopy of the forest covering most of the land surface (Poussart et al 2004). The dark shades of the forest allow for incoming solar radiation to be absorbed rather than reflected. Image by Hafizh (2016).

Sumatra has many mountains with an average elevation of 1,500 meters above sea level according to UNESCO (2004). There is little to no snow present ever on any mountains in Sumatra. The high mountains are able to trap moisture and even make the atmosphere unstable which leads to a squall line. Image by Stefanie Weijsters.

Monsoon circulation on the island can cause weather phenomena such as squall lines. These squall lines can cause heavy rainfall, large hail and intense winds according to Lo et al (2016). During the monsoon season, southwest winds pass over the mountains. This results in mountain waves that cause the surrounding atmosphere to become unstable. This results in thunderstorms. The thunderstorms begin to merge into each other and create a squall line according to Lo et al (2016). Image by Fred Roswold.

The image above shows the Malayan tapir. One of the unique species that lives on the island of Sumatra. Sumatra’s unique climate is able to house 10,000 plant species, 201 mammal species and 580 bird species (UNESCO 2004). Over 60 of these species are endemic, meaning they are only found on the island of Sumatra. Image by Daniel Sendecki.