Thursday, December 24, 2020

Meteorological Sub-divisions of India 2020


India has been divided into 36 subdivisions by Indian Meteorological Department on the basis of meteorological data and also considering practical applicability.

For reasons of practical convenience, compilation of statistics, issue of weather warnings to government functionaries and informing the general public, the sub-divisional boundaries were always made to conform at least to the jurisdiction of basic revenue districts.

R. R. Kelkar and O. P. Sreejith (2020), IMD Pune

This process was undertaken as -
  • Large states with varying climate were divided into smaller divisions on meteorological grounds.
  • Small states and Union Territories with similar meteorological climate were combined together.
  • Finally, IMD gave names to those sub-divisions that did not follow existing political subdivisions.
To simplify for understanding, the 36 meteorological subdivisions of India can be classified as-

Criteria of sub-divisions

Number of subdivisions

States

Named after the state

9 subdivisions

o  Arunachal Pradesh,

o  Odisha,

o  Jharkhand,

o  Bihar,

o  Uttarakhand,

o  Punjab,

o  Himachal Pradesh,

o  Chattisgarh,

o  Telangana.

Group of smaller states or UTs - States and UTs with small area and similar climate

6 sub-divisions

o  Assam and Meghalaya,

o  Nagaland, Manipur, Mizoram and Tripura,

o  Haryana, Chandigarh and Delhi,

o  Jammu and Kashmir and Ladakh,

o  Tamil Nadu, Puducherry and Karaikal,

o  Kerala and Mahe.

Larger states divided into two

12 sub-divisions

o  East Rajasthan,

o  West Rajasthan,

o  East Uttar Pradesh,

o  West Uttar Pradesh,

o  East Madhya Pradesh

o  West Madhya Pradesh.

o  Gujarat Region

o  Saurashtra and Kutch.

o  Sub-Himalayan West Bengal and Sikkim

o  Gangetic West Bengal.

o  Rayalaseema,

o  Coastal Andhra Pradesh and Yanam.

Larger states divided into three  and more than 3 - Larger states which have a greater variation in climate

7 sub-divisions

o Karnataka,

o North Interior Karnataka  

o South Interior Karnataka

o Konkan and Goa,

o Madhya Maharashtra,

o Marathwada,

o Vidarbha.

Islands

2 sub-divisions

o Andaman and Nicobar Islands in the Bay of Bengal

o Lakshadweep islands in the Arabian Sea.


To further understand the history of Meteorological sub-divisions of India, refer to this research article by R. R. Kelkar and O. P. Sreejith (2020),

Reference –

IMD website, India Meteorological Department, Ministry of earth Sciences, Government of India. Accessed on 24/12/2020. https://mausam.imd.gov.in/

Map Data Source – Meteorological Subdivisions map, IMD website, India Meteorological Department, Ministry of earth Sciences, Government of India. Accessed on 24/12/2020. https://mausam.imd.gov.in/imd_latest/contents/index_rainfall_subdiv.php

R. R. Kelkar and O. P. Sreejith, (2020). Meteorological sub-divisions of India and their geopolitical evolution from 1875 to 2020. Mausam, 71, 4 (October 2020), 571-584. https://metnet.imd.gov.in/imdmausam/

Wednesday, December 16, 2020

Blue carbon

 
Mangrove Forest, Andaman and Nicobar Islands, India.

 Blue carbon is the carbon stored in coastal and marine ecosystems such as mangroves, tidal marshes and coastal seagrass meadows. These systems store large amount of carbon not only in the above and below ground biomass of the plants i.e. tree trunks, stems and leaves and root systems but also in the carbon-rich organic soils. 

 

Watch this video by Conservation International, to understand What is Blue carbon ?

 

These ecosystems are valuable to coastal communities as they provide food, timber, source of livelihood and security from storms/cyclones etc. In the same way, they have many environmental benefits such as filtration of saline water, prevention of coastal erosion and biodiversity protection.


Mangroves are estimated to be worth at least US$1.6 billion each year in ecosystem services that support coastal livelihoods and human populations around the world*.

The Blue Carbon Initiative

 

Recently their role for mitigating climate change effects has also been recognized due to their ability to remove carbon dioxide (CO2) from the atmosphere. They can act as huge carbon sinks due to their capacity to store more carbon than the terrestrial forest.

Conversely, if they are degraded or damaged, not only their carbon sink capacity is lost but it releases the stored carbon causing carbon dioxide (CO2) release that can contribute to rise in greenhouse gases. 

 

Experts estimate that as much as 1.02 billion tons of carbon dioxide are being released annually from degraded coastal ecosystems, which is equivalent to 19% of emissions from tropical deforestation globally*.

The Blue Carbon Initiative

 

On site projects and policy to protect and restore “Blue Carbon” ecosystems are being developed country wise as well as globally. For more information visit the The Blue Carbon initiative Website.


References – 

IUCN. Issues brief - Blue carbon. International Union for Conservation of Nature website, https://www.iucn.org/resources/issues-briefs/blue-carbon. Accessed on 16/12/2020.

NOAA. What is Blue Carbon? National Ocean Service website, https://oceanservice.noaa.gov/facts/bluecarbon.html. 07/24/19

The Blue Carbon Initiative. Mitigating climate change through coastal ecosystem management. The Blue Carbon Initiative website. https://www.thebluecarboninitiative.org/. Accessed on 16/12/2020