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/

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

 

Observing the Earth – Journey of Indian Earth observation satellites from Bhaskara to EOS

 

From the humble start from Bhaskara I to EOS-1, the Indian Earth observation satellite technology has advanced significantly. Earlier, the technology required by the Indian satellite system was imported from foreign nations, however with time state of the art technology has been developed indigenously. In this short journey, there has been remarkable advancement of technology in the earth observation satellite in resolution, sensor technology, application areas, coverage etc.

Experimental stage - The beginning of the Indian earth observation satellite journey started with experimental satellites like Bhaskara I in 1979 followed by Rohini RS-D1, Bhaskara II and Rohini RS -D2. These had limited capabilities in terms of sensor and resolution.

IRS series - In 1988, Indian Space Research Organization launched the first indigenous operational remote sensing satellite in the IRS series, i.e  IRS – 1A. After this came the many satellites in IRS series i.e. 1A, 1B, 1E, P2,1C, P3, 1D, P4 and P6, each with improved capabilities than the previous one. IRS- P6 (which was continued as Resourcesat), launched in 2003, employed advanced multi-spectral LISS IV, LISS III and AWiFS sensor. The latest in this series is Resourcesat 2-A, launched in 2016, with much improved technology.

Oceansat series – The IRS – P4 satellite, launched in 1991, specifically for ocean applications was first one in the Oceansat series. The second satellite in this series is Oceansat -2 launched in 2009 with Ocean Colour Monitor-2 (OCM-2), Scatterometer and Radio Occultation Sounder for Atmospheric (ROSA) sensors.  SCASAT – 1 is the continuing mission for Oceansat series with wind scatterometer sensor. The third one in this series Oceansat -3 is expected to be launched in 2020.

Cartosat series –The first satellite, Cartosat - I was launched in 2005 with resolution of 2.5 meters. Then came Cartosat 2 in 2007, 2A in 2008 and 2B in 2010, 2C in 2016, 2D and 2E in 2017, 2F in 2018 and the latest one is Cartosat 3 in 2019. The imaging capability of each is better than the last one. The latest in the series, i.e. Cartosat – 3 can produce scene specific spot image with high resolution of 0.25 meters.

RISAT series – India entered into radar imaging through RISAT – 2 satellite in 2009. The second in the series, RISAT – 1, was delayed and launched 2012. The next in the series was RISAT – 2B and 2BR -1 in 2019 and the latest one in the series is EOS-1 launched in 2020.

INSAT series – INSAT series satellites are advanced meteorological satellites There are two satellite in this series i.e. INSAT – 3D launched in 2013 and INSAT – 3DR launched in 2016.

Other than these, there are few individual special earth observation satellites were launched for specific purposes.

Technology experiment satellite (TES) - Experimental high resolution Technology experiment satellite (TES) launched in 2001.

Megha torpiques- An indo-french satellite mission launched in 2011.

SARAL (Satellite with ARgos and ALtiKa)- Another Indo – France collaboration mission, launched in 2013

HysIS - Hyperspectral imaging satellite launched in 2018.

The Indian earth observation satellite journey is not finished here but has just started. The present observation satellite system with high resolution multi-spectral remote sensing data is delivering data which is not only an asset for the scientific community but also for development of the nation.

 

Reference - 

ISRO website, Department of Space, Indian Space Research Organization, https://www.isro.gov.in/about-isro

Image source - Free-Photos from Pixabay