Saturday, July 27, 2013

India's Wettest Places - Rajamalai, Kerala - Series No.2

Whenever people in India ask for wettest / Rainiest places they only know Cherrapunji or Mawsynaram or Agumbe. In these series, you will come to various places which i have identified to be wettest places of India. This series will be published every weekly. If you are fan of Heavy Rains and want to know more than Cherrapunji. Please Read it. Its only a compilation of data from various sources / articles / research materials.

The Eravikulam National Park is situated in the high ranges of Southern Western Ghats of Idukki district, Kerala, having an elevation up to 2695 mts with an average base elevation of 2000mts. The nearest town is Munnar. The park has the highest peak in South India, Anamudi, scaling to 2695mts and is located in this park. Rajamalai is the headquarters of the park, and is located 16 km from Munnar. There is a motorable road up to Rajamalai. Rajamalai is also known for its heavy rainfall. Here we will analyze the last 10 years rainfall in Rajamalai and the data reveal it is one of the few stations which get very heavy rainfall in this world. 

The park is represented by undulating terrain flanked on all sides by moderate to steep slopes. The major terrain types are slopes (low to steep), flat mountain tops and valleys (water logged and well drained). The main body of the Park is comprised of a high rolling plateau, with a base elevation of about 2000m. Most of the knolls and peaks on the plateau rise 100 to 300m above it. The main plateau area is split roughly in half from northwest to southeast by the Turner’s Valley. The southern fringe of the Park is mostly precipitous with broken cliffs descending from Anamudi, Umayamala and surrounding massifs. In contrast to the sustained and extremely steep escarpment along the eastern fringe of the Nilgiri plateau, the plateau fringe in the Eravikulam area is generally less steep with cliffs often grading into rock slabs with numerous brakes of grassland, shrubs or forests. Only along the west-facing crust between Kattumalai and Kumarikkalmalai, does the edge of the plateau resemble that of the Nilgiri plateau in this regard. In addition, cliffs are usually not abrupt, but rounded both horizontally and vertically. Where exposed, the rock usually has an irregular surface with numerous small dikes and discontinuities. 

Anaimudi - Tallest peak in South India - Photo - Indiareign

Etymologically, Eravikulam denotes streams and pools. Many perennial streams criss-cross the park. They merge to form tributaries of the Periyar river and Chalakudiyar River on the west and the east flowing Cauvery River in Tamil Nadu. Lakkom Water falls is in this region. The Western Ghats, Anamalai Sub-Cluster, including all of Eravikulam National Park, is a World Heritage Site. The Eravikulam ecosystem is a strange admixture of temprature and tropical qualities due to the combined effects of altitude as well as latitude. It is exceptionally rich in orchids and balsams. The spectacular mass flowering of the shrub neelakurunji (Phlebophyllum kunthianum) takes place in the grasslands in cycles of the 12yrs. The next neelakurunji 'outburst' is due in the year 2018.

Rajamalai - Photo - Praveen Emmanuel

During the colonial days, the High Range Game Preservation Association managed the area as a Game Preserve for the erstwhile Kannadevan Hills Produce Company. The Muduvan tribals, known for theit tracking skills, were employed as game watchers. they are the original inhabitants of these hills.  The area was taken over in 1971 by the Kerala Government and declared as a Sanctuary in 1975. It was upgraded to a national park in 1978 in recognition of it's unique ecological values. The planters community and the Muduvans continue their association with the protection and management of the park.

Heavy Rainfall

The climate of the Park is known as tropical montane. The influence of altitude over tropical latitude brings about the characteristic climate. The monsoon dominates the annual weather cycle. The year consists of four seasons: (1) Winter, from December to February; (2) Summer or pre-monsoon, from March to May; (3) Southwest monsoon from June to September; and (4) Northeast monsoon, from October to November. The Park is mostly covered up in mist from June to November. During southwest monsoon, winds are consistently from the west and strong, at times reaching an estimated 80 km/hr. Low velocity winds occur during northeast monsoon and in the winter season. During February-March, dry winds blow from the east, growing stronger at times.

In Eravikulam, the data on rainfall between 2001 and 2010 are collected from the Rajamalai, Vaguvarrai and Nyamakad. More than 70% of the annual rainfall is contributed by the south-west monsoon. Summer rains occur in the months of February, March and April. The rainfall over the last 10 years and month wise rainfall data for 3 years in the nearby estates are tabulated below (Table 1 and 2). But rainfall pattern varies greatly across the Park. The average rainfall in Rajamalai in the last 10 years is around 7000 mm.

Available Rainfall data in the Eravikulam National Park in past 10 years in mm

Rajamalai is not wetter than Walakkad in Kerala but is on par with Pochippara or even better as Rajamalai crossed 9000 mm mark 3 times in last 10 years but Pochippara peak rainfall is only 8400 mm. I would rank Walakkad as the wettest place in Kerala followed by Rajamalai as the second wettest and then Pochippara. 

Source: Compilation from  KFRI, Wikipedia and Rainfall data from own research.


See also previous series


India's Wettest Places - Walakkad, Kerala - Series No.1


chessplayerus said...

Dear Pradeep,
your blogs about rainfall in India are very interesting. I am working at the GPCC (Global Precipitation Climatology Centre) operated by the German Weather Service under the auspices of the WMO. We are generating global analyses of monthly precipitation. Cherrapunji and Mawsynram are amongst the stations with the worldwide highest rainfall amounts. While we do have a long time series for Cherrapunji, we have data Mawsynram only for 1940-1969, with a gap in 1945-1947.
Could you please help us to improve our data base for Mawsynram?
Best regards

Pradeep said...

Thank you. I too have the data series from 1940-1969 only.

Only from 2013, Mawsynram i am tracking it. Before which it was not in public domain.

U have purchase the rainfall from IMD

Karthik Narayan said...

Rajamalai is geographically very close to Cinchona and Valparai as well

Pradeep said...

Karthik Narayan

Chincona is close to Lower Nirar then Chinnakallar and Upper Nirar

Your are spot on. It is also close to Rajamalai

John Richard Thomas said...

IT is really interesting thankyou for your valuable informations..iam also working in climate change regards...

Amarnath A P said...


I am very interested in weather (temp and rainfall) and its data. Thanks for providing these data.

Btw - which is the wettest place in Tamilnadu (I guess chinnakalar - but not sure).

Pradeep said...

Yes Chinnakallar and Upper Nirar are wettest place in Tamil Nadu.

reghuram said...

Dear Pradeep Emmanuel a thousand thanx for your rainfall info. I am an avid weather watcher and my query is regarding any correlation between the mango showers in kerala and the western disturbance of North India. In my small research on this i have noticed that whenever there is a strong western disturbance thee is an appreciable increase in temperature in kerala, and also absence of thunderstorm activity. Could you please enlighten?

alleppey houseboat said...

Thanks for sharing this wonderful post . It is important and very useful, and the articles are nice to share everyone.
alleppey houseboats

Harish Raja said...

What is the highest 24 hour rainfall recorded anywhere in namakkal district