Climate of Tamil Nadu

Climate of Tamil Nadu (State in South India)

Daytime view of an almost lifeless expanse, dry rocks and sand marked only by the odd lone shrub. The dry terrain reaches to a chain of mountains in the far distance, near the horizon. A bank of clouds soars above the void, but it does not appear to hold the promise of rain. A far darker, larger, more turgid cloud bank sits above the and distant mountains, above the horizon.
A semi-arid wasteland near Tirunelveli, Tamil Nadu. Monsoon clouds dump torrents of rain on lush forests only kilometres away in windward-facing Kerala. The Agasthyamalai Range mostly stops them from reaching Tirunelveli.
Late daytime view looking far out over an ocean from a beach, which is out of view off the bottom margin. Three-fourths of the shot features a sky marked by heavy cloud cover, which is parting near the middle, revealing a dazzlingly bright cerulean blue sky that darkens near the margins. The ocean is striated with waves coming in parallel to the horizon.
Late-season monsoonal sunset, Coromandel Coast
Chill climate view of tamilnadu from a house
Life in Tamil Nadu
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The Climate of Tamil Nadu, India is generally tropical and features fairly hot temperatures over the year except during the monsoon seasons. The city of Chennai lies on the thermal equator,[1] which means Chennai and Tamil Nadu does not have that much temperature variation.

History

Under the Köppen climate classification the greater part of Tamil Nadu fills under Tropical savanna climate and smaller portions of the state fall under Humid subtropical climate; the climate of the state ranges from dry sub-humid to semi-arid.

Seasons

Summer

The summer in Tamil Nadu runs throughout March, April and May and is characterized by intense heat and scant rainfall across the state.

Monsoon

The state has three distinct periods of rainfall: advanced rainfall; rainfall from the tropical cyclones emerging in the neighbourhood of the Andaman Islands during the Retreat of Monsoons(October–November): and the North-East monsoon during the months of October–December, with dominant northeast monsoon winds from the western disturbances emerging over the Bay of Bengal. The dry season is from February to early June. Mid-June to December is the monsoon months.

Since the state is entirely dependent on rains for recharging its water resources, monsoon failures lead to acute water scarcity and severe droughts.

Tamil Nadu is classified into seven agro-climatic zones: north-east, north-west, west, southern, high rainfall, high altitude hilly, and Cauvery Delta (the most fertile agricultural zone).

Statistics

Temperature

Average temperatures in various cities of Tamil Nadu (°C)[2][3][4]
Winter
(Jan
– Feb)
Summer
(Mar – May)
Monsoon
(Jun – Sep)
Post-monsoon
(Oct – Dec)
Year-round
City Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Avg
Chennai 24 25 27 29 31 30 30 28 27 26 25 24 31
Coimbatore 25 26 28 29 29 27 25 26 25 24 23 24 29
Madurai 25 27 29 31 32 30 29 28 27 25 24 25 32
Tiruchirapalli 25 26 28 29 31 32 30 29 29 27 25 24 32

Precipitation

Average precipitation in various cities of Tamil Nadu (mm)[2][3][4]
Winter
(Jan – Feb)
Summer
(Mar – May)
Monsoon 1
(Jun – Sep)
Monsoon 2
(Oct – Dec)
Year-round
City Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total
Chennai
Coimbatore
Madurai
Tiruchirappalli

Weatherboxes

Climate data for Chennai (Köppen Aw)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 34.4
(93.9)
36.7
(98.1)
40.6
(105.1)
42.8
(109.0)
45.0
(113.0)
43.3
(109.9)
41.1
(106.0)
40.0
(104.0)
38.9
(102.0)
39.4
(102.9)
35.4
(95.7)
33.0
(91.4)
45.0
(113.0)
Mean daily maximum °C (°F) 29.3
(84.7)
30.9
(87.6)
32.9
(91.2)
34.5
(94.1)
37.1
(98.8)
37.0
(98.6)
35.3
(95.5)
34.7
(94.5)
34.2
(93.6)
32.1
(89.8)
29.9
(85.8)
28.9
(84.0)
33.1
(91.6)
Daily mean °C (°F) 25.2
(77.4)
26.6
(79.9)
28.7
(83.7)
30.9
(87.6)
32.9
(91.2)
32.4
(90.3)
30.9
(87.6)
30.3
(86.5)
29.8
(85.6)
28.4
(83.1)
26.5
(79.7)
25.3
(77.5)
29.0
(84.2)
Mean daily minimum °C (°F) 21.2
(70.2)
22.2
(72.0)
24.2
(75.6)
26.6
(79.9)
28.0
(82.4)
27.5
(81.5)
26.4
(79.5)
25.9
(78.6)
25.6
(78.1)
24.6
(76.3)
23.1
(73.6)
21.9
(71.4)
24.8
(76.6)
Record low °C (°F) 13.9
(57.0)
15.0
(59.0)
16.7
(62.1)
20.0
(68.0)
21.1
(70.0)
20.6
(69.1)
21.0
(69.8)
20.5
(68.9)
20.6
(69.1)
16.7
(62.1)
15.0
(59.0)
13.9
(57.0)
13.9
(57.0)
Average rainfall mm (inches) 25.9
(1.02)
3.4
(0.13)
3.5
(0.14)
14.4
(0.57)
34.2
(1.35)
55.8
(2.20)
103.8
(4.09)
126.8
(4.99)
147.7
(5.81)
315.6
(12.43)
399.9
(15.74)
177.4
(6.98)
1,382.9
(54.44)
Average rainy days 1.4 0.8 0.3 0.8 1.8 4.0 6.5 7.7 7.3 10.9 11.5 5.8 58.8
Average relative humidity (%) (at 17:30 IST) 67 66 67 70 68 63 65 66 71 76 76 71 69
Average dew point °C (°F) 20
(68)
20
(68)
22
(72)
24
(75)
24
(75)
23
(73)
23
(73)
23
(73)
24
(75)
24
(75)
23
(73)
21
(70)
23
(73)
Mean monthly sunshine hours 232.5 240.1 291.4 294.0 300.7 234.0 142.6 189.1 195.0 257.3 261.0 210.8 2,848.5
Mean daily sunshine hours 7.5 8.5 9.4 9.8 9.7 7.8 4.6 6.1 6.5 8.3 8.7 6.8 7.8
Average ultraviolet index 7 7 7 8 8 8 8 7 7 6 7 7 7
Source 1: Indian Meteorological Department
Source 2: Japan Meteorological Agency[5] Weather Atlas[6] Time and Date (dewpoints, 2005-2015)[7]
Climate data for Coimbatore (Köppen BSh)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 35.9
(96.6)
38.8
(101.8)
40.8
(105.4)
42.6
(108.7)
41.2
(106.2)
38.0
(100.4)
36.2
(97.2)
36.0
(96.8)
37.8
(100.0)
36.8
(98.2)
34.2
(93.6)
34.4
(93.9)
42.6
(108.7)
Mean daily maximum °C (°F) 30.8
(87.4)
33.6
(92.5)
36.0
(96.8)
36.7
(98.1)
35.4
(95.7)
32.4
(90.3)
31.6
(88.9)
31.9
(89.4)
32.7
(90.9)
31.9
(89.4)
30.1
(86.2)
29.6
(85.3)
32.7
(90.9)
Mean daily minimum °C (°F) 18.8
(65.8)
19.8
(67.6)
21.8
(71.2)
23.7
(74.7)
23.7
(74.7)
22.6
(72.7)
22.0
(71.6)
22.0
(71.6)
22.1
(71.8)
22.0
(71.6)
20.9
(69.6)
19.0
(66.2)
21.5
(70.7)
Record low °C (°F) 12.2
(54.0)
12.8
(55.0)
15.8
(60.4)
18.2
(64.8)
15.6
(60.1)
18.3
(64.9)
16.1
(61.0)
16.1
(61.0)
16.7
(62.1)
15.9
(60.6)
14.1
(57.4)
12.4
(54.3)
12.2
(54.0)
Average rainfall mm (inches) 7.5
(0.30)
4.2
(0.17)
25.7
(1.01)
43.6
(1.72)
55.2
(2.17)
23.7
(0.93)
25.3
(1.00)
36.1
(1.42)
52.8
(2.08)
157.5
(6.20)
134.6
(5.30)
33.3
(1.31)
599.5
(23.61)
Average rainy days 0.4 0.6 1.3 2.9 3.5 2.7 2.9 2.8 3.5 8.2 6.6 2.2 37.6
Average relative humidity (%) (at 17:30 IST) 41 33 31 42 56 66 68 68 66 67 64 53 54
Source: India Meteorological Department[12] [13]
Climate data for Madurai (Köppen Aw/As/BSh)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 39.1
(102.4)
38.5
(101.3)
41.7
(107.1)
42.1
(107.8)
44.5
(112.1)
42.2
(108.0)
40.6
(105.1)
40.0
(104.0)
39.8
(103.6)
40.0
(104.0)
38.0
(100.4)
37.0
(98.6)
44.5
(112.1)
Mean daily maximum °C (°F) 30.8
(87.4)
33.3
(91.9)
36.0
(96.8)
37.2
(99.0)
37.9
(100.2)
37.2
(99.0)
36.5
(97.7)
36.2
(97.2)
35.1
(95.2)
33.1
(91.6)
30.6
(87.1)
30.0
(86.0)
34.5
(94.1)
Mean daily minimum °C (°F) 19.6
(67.3)
21.5
(70.7)
23.4
(74.1)
25.6
(78.1)
26.3
(79.3)
26.2
(79.2)
25.9
(78.6)
25.5
(77.9)
24.6
(76.3)
23.7
(74.7)
22.7
(72.9)
21.3
(70.3)
23.9
(75.0)
Record low °C (°F) 15.6
(60.1)
10.5
(50.9)
16.9
(62.4)
19.4
(66.9)
17.8
(64.0)
17.8
(64.0)
19.4
(66.9)
20.6
(69.1)
18.5
(65.3)
18.9
(66.0)
17.2
(63.0)
16.7
(62.1)
10.5
(50.9)
Average precipitation mm (inches) 8.5
(0.33)
11.0
(0.43)
18.3
(0.72)
60.1
(2.37)
80.6
(3.17)
34.3
(1.35)
56.9
(2.24)
93.9
(3.70)
121.5
(4.78)
185.8
(7.31)
147.2
(5.80)
51.3
(2.02)
869.4
(34.23)
Average precipitation days 0.8 1.1 1.2 3.3 4.0 2.2 2.9 4.6 6.6 9.7 6.8 3.4 46.6
Average relative humidity (%) 77 77 76 72 70 68 70 71 71 76 78 78 74
Average ultraviolet index 7 7 8 8 8 8 8 8 7 7 6 6 7
Source 1: Indian Meteorological Department Mean data from 1981–2010[14][15]
Source 2: Weather Atlas[16]
Climate data for Tiruchirappalli (Köppen Aw/As)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 35.6
(96.1)
40.0
(104.0)
42.2
(108.0)
42.8
(109.0)
43.3
(109.9)
43.9
(111.0)
41.1
(106.0)
40.6
(105.1)
40.6
(105.1)
38.9
(102.0)
36.7
(98.1)
35.6
(96.1)
43.9
(111.0)
Mean daily maximum °C (°F) 30.3
(86.5)
32.8
(91.0)
35.7
(96.3)
37.5
(99.5)
38.2
(100.8)
37.1
(98.8)
36.3
(97.3)
35.8
(96.4)
35.0
(95.0)
32.8
(91.0)
30.4
(86.7)
29.6
(85.3)
34.3
(93.7)
Mean daily minimum °C (°F) 20.6
(69.1)
21.5
(70.7)
23.5
(74.3)
26.1
(79.0)
26.8
(80.2)
26.6
(79.9)
26.1
(79.0)
25.7
(78.3)
24.9
(76.8)
24.2
(75.6)
22.8
(73.0)
21.2
(70.2)
24.2
(75.6)
Record low °C (°F) 14.4
(57.9)
13.9
(57.0)
15.6
(60.1)
18.3
(64.9)
19.4
(66.9)
18.0
(64.4)
20.1
(68.2)
20.6
(69.1)
20.6
(69.1)
18.9
(66.0)
16.7
(62.1)
14.4
(57.9)
13.9
(57.0)
Average rainfall mm (inches) 13.3
(0.52)
3.6
(0.14)
5.3
(0.21)
29.6
(1.17)
67.0
(2.64)
38.3
(1.51)
60.5
(2.38)
69.9
(2.75)
153.4
(6.04)
153.9
(6.06)
168.0
(6.61)
81.4
(3.20)
844.2
(33.24)
Average rainy days 0.9 0.4 0.6 1.7 3.8 2.6 2.7 4.1 7.1 9.2 8.1 5.1 46.3
Average relative humidity (%) (at 17:30 IST) 54 43 37 41 42 44 45 46 52 64 70 65 50
Source: India Meteorological Department[17][18]

Desert Soil

Mostly, desert soils are seen around Madurai , Virudhunagar, Sivaganga, Ramanathapuram and some parts of Tirunelveli dist, a few adjoining districts. These districts are formally known as the desert districts of Tamil Nadu.

Disasters

Floods

During the 2015 South Indian floods (most affected districts: Chennai, Kanchipuram and Cuddalore), Chennai received 1,049 mm (41.3 in) of rainfall in November, the highest recorded since November 1918 when 1,088 mm (42.8 in) of rainfall was recorded.[24][25] The flooding in Chennai was described as the worst in a century.[26]

Cyclones

2004 Asian tsunami disaster

Drought & famine

Pollution

The air quality of industrial areas in Ennore, as well as in Poes Garden and Boat Club are above the standards prescribed by the environment ministry, according to a report by Coastal Resource Centre.

The centre took eleven air samples in and around North Chennai and Chennai city as part of their air quality study in Ennore 2016. 24-hour samples were taken using filters fitted to a low volume air sampler and analysed for PM 2.5 (Particulate Matter or dust less than 2.5 micrometres in size). The key documented sources of PM 2.5 pollution are automobile exhaust, burning of coal, burning garbage and landfill, smelting processing of metals.

Surprisingly, 10 out of the 11 air samples were between 1.4 and 3.7 times higher than prescribed by the Ministry of Environment, Forests and Climate Change. The quality of air in Nallathaneer Odai Kuppam in Ennore is the highest with 220 micrograms of particulate matter per cubic meter of air.

Other areas from Ennore include Manali with 156 ug/m3, Sivanpadaiveethi Kuppam with 156. 90 ug/m3 and Kodingayur with 154.90 ug/m3 which is all considered very unhealthy according to the US Environment Protection Agency.

The Ennore region has 3300 MW of installed coal power plant capacity, with more than 1500 acres as dedicated coal ash dumps, says the report.

Highlighting the health effects of bad air quality, Dr Hissamudin Papa, Founder and Director, HUMA Hospitals said, "We visited these areas in Ennore and found various health issues. Children who are 14 to 15 years old look like they are 8 years old. Women have hormonal issues and infertility. Many people have chronic obstructive pulmonary disease in these areas. The pollution needs to be reduced in these areas.

Even areas like Poes Garden and Boat Club ranged 104 and 101 UG/ M3 which is considered unhealthy according to US EPA standards. "The high concentration of polluting industries in the city’s northern and southern edges is affecting all of Chennai," said Dr Rakhal Gaitonde, a public health specialist.

According to the report by the Coastal Resource Centre, the level of manganese in eight of the eleven samples exceed the US EPA reference concentration for exposure to manganese. There are no standards in India for manganese in ambient air. Also, the levels of calcium silicon and crystalline silica, which are enriched in coal ash were found in the air samples.

"Manganese and nickel are well-known toxins and their effects are well-documented. Manganese is predominantly a neurotoxin, while nickel is a carcinogen. The measurement of such toxic substances from the rooftops of human settlements is indeed a cause of concern," added Dr Rakhal.

The Coastal Resource Centre wants the Tamil Nadu government to take immediate action to improve the air quality in Ennore. "The government needs to impose a moratorium on all industrial activities till the environment is restored, initiate long-term and continuous monitoring in Ennore region," said Nityanand Jayaraman, an environment activist.

He added, "No norms are followed by the Tamil Nadu Pollution Control Board. Why should people living in North Chennai have to bear all the harmful effects of the industries?"

The Coastal Resource Centre also wants the government to apprehend polluters and take corrective actions to bring the levels of dust and heavy metals in the dust below detection limits in residential areas.

See also

References

  1. ^ "About Chennai" (PDF). Chennai Metropolitan Development Authority. p. 1. Archived from the original (PDF) on 22 September 2020. Retrieved 28 December 2012.
  2. ^ a b "Weatherbase". Retrieved 19 October 2012.
  3. ^ a b "Wunderground". Weather Underground. Retrieved 19 October 2012.
  4. ^ a b "Weather.com". The Weather Channel. Retrieved 19 October 2012.
  5. ^ "Normals Data". Japan Meteorological Agency. Retrieved 11 May 2020.
  6. ^ "Climate and monthly weather forecast Chennai, India". Weather Atlas. Retrieved 13 June 2022.
  7. ^ "Climate & Weather Averages in Chennai, Tamil Nadu, India". Time and Date. Retrieved 18 July 2022.
  8. ^ "Station: Chennai (Nungambakkam) Climatological Table 1981–2010" (PDF). Climatological Normals 1981–2010. India Meteorological Department. January 2015. pp. 185–186. Archived from the original (PDF) on 5 February 2020. Retrieved 2 March 2020.
  9. ^ "Extremes of Temperature & Rainfall for Indian Stations (Up to 2012)" (PDF). India Meteorological Department. December 2016. p. M192. Archived from the original (PDF) on 5 February 2020. Retrieved 2 March 2020.
  10. ^ "Table 3 Monthly mean duration of Sun Shine (hours) at different locations in India" (PDF). Daily Normals of Global & Diffuse Radiation (1971–2000). India Meteorological Department. December 2016. p. M-3. Archived from the original (PDF) on 5 February 2020. Retrieved 2 March 2020.
  11. ^ "Chennai Climatological Table 1981–2010". India Meteorological Department. Retrieved 2 March 2020.
  12. ^ "Extremes of Temperature & Rainfall for Indian Stations (Up to 2012)" (PDF). India Meteorological Department. December 2016. p. M193. Archived from the original (PDF) on 5 February 2020. Retrieved 7 March 2020.
  13. ^ "Station: Coimbatore (Peeamedu) Climatological Table 1981–2010" (PDF). Climatological Normals 1981–2010. India Meteorological Department. January 2015. pp. 203–204. Archived from the original (PDF) on 5 February 2020. Retrieved 7 March 2020.
  14. ^ "Climatology of Madurai". Indian Meteorological Department. 2011. Retrieved 11 April 2015.
  15. ^ "Climate - Record highs and lows of Madurai" (PDF). Indian Meteorological Department. 2015. Archived from the original (PDF) on 16 March 2014. Retrieved 11 April 2015.
  16. ^ "Climate and monthly weather forecast Madurai, India". Weather Atlas. Retrieved 19 July 2022.
  17. ^ "Extremes of Temperature & Rainfall for Indian Stations (Up to 2012)" (PDF). India Meteorological Department. December 2016. p. M204. Archived from the original (PDF) on 5 February 2020. Retrieved 30 March 2020.
  18. ^ "Station: Tiruchirapalli (A) Climatological Table 1981–2010" (PDF). Climatological Normals 1981–2010. India Meteorological Department. January 2015. pp. 745–746. Archived from the original (PDF) on 5 February 2020. Retrieved 30 March 2020.