*This post is technical in nature, hence better suited if you have geography as optional.

Stable oxygen isotopic composition (δ18O) of foraminifera from the sediments of the Northern Indian Ocean has been used to decipher past changes in the intensity of the South Asian Monsoon. The interpretation of planktonic foraminifera δ18O is mostly based on a combination of sea surface temperature, monsoon runoff and the global ice-volume effect.

During summer, the eastward flowing summer monsoon current carries the high salinity water from the Arabian Sea to the Bay of Bengal, whereas the Bay of Bengal receives fresh water both from direct rains and runoff from the Ganga-Brahmaputra rivers.

This low salinity water is transported from the Bay of Bengal to the southeastern Arabian Sea during winter by the winter monsoon current (WMC) driven by the dry northeasterly winds.

The West India Coastal Currents (WICC) carries this low saline water from southeastern Arabian Sea to the northern Arabian Sea (Fig. 1b).

During the winter monsoon, high precipitation occurs over southeastern India (the southern states of Tamil Nadu and southeast coastal Andhra Pradesh), while rainfall at this time is quite low over Kerala compared to the summer monsoon.

Duplessy (1982), analyzing several sediment cores from the Bay of Bengal, showed that the summer monsoon rain was significantly reduced during the Last Glacial Maximum (LGM).

Oxygen isotopes of LGM planktonic foraminifera were relatively higher, resulting from reduced freshwater discharge from the major monsoon fed Indian rivers.

Likewise, Sarkar et. al. (1990) showed that the winter monsoon rains intensified during LGM by analyzing four different species of planktonic foraminifera from a sediment core from the Eastern Arabian Sea. Kudrass et. al. (2001) showed that the runoff into the Bay of Bengal had steadily increased from 21 ka (LGM) to ~4ka.

Seawater sampling locations in the Eastern Arabian Sea (Deshpande et al., 2013), sub-divided into four regions: I 6oN-12oN, II 12oN-18oN, III 18oN-22oN and IV 4oN-10oN/79oE- 60oE. b Locations of sediment cores. Region IV marked here is smaller because high resolution analyses of sediment cores have not been reported west of this box.

Seawater sampling locations in the Eastern Arabian Sea (Deshpande et al., 2013), sub-divided into four regions: I 6oN-12oN, II 12oN-18oN, III 18oN-22oN and IV 4oN-10oN/79oE- 60oE. b Locations of sediment cores. Region IV marked here is smaller because high resolution analyses of sediment cores have not been reported west of this box.

Using a fresh data set (Deshpande et. al., 2013) of seawater δ18O and salinity from the Eastern Arabian Sea (Fig. 1a), it was investigated that the seasonal variation in the salinity-δ18O relation in the Eastern Arabian Sea, dividing the latter into four major regions (Fig. 1a), three of which fall under the influence of the WICC, and one under the influence of the WMC.

The seasonal variation in the salinity-δ18O relation for all four regions shows (except for region II that receives copious summer monsoon runoff from the Western Ghats), the summer monsoon runoff from the subcontinent to the Bay of Bengal, propelled by winter monsoon winds towards the Arabian Sea, appears to be the dominant control on the modern salinity-δ18O relation in the surface regions of the eastern Arabian Sea.


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  • Context:-

    At the recently concluded Leaders’ Summit on Climate in April 2021, Lowering Emissions by Accelerating Forest Finance (LEAF) Coalition, a collective of the United States, United Kingdom and Norway governments, came up with a $1 billion fund plan that shall be offered to countries committed to arrest the decline of their tropical forests by 2030.

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    What is LEAF Coalition?

    • Lowering Emissions by Accelerating Forest Finance (LEAF) Coalition, a collective of the United States, United Kingdom and Norway governments, came up with a $1 billion fund.
    • LEAF is supported by transnational corporations (TNCs) like Unilever plc, Amazon.com, Inc, Nestle, Airbnb, Inc as well as Emergent, a US-based non-profit.

    Why LEAF Coalition?

    • The world lost more than 10 million hectares of primary tropical forest cover last year, an area roughly the size of Switzerland.
    • Ending tropical and subtropical forest loss by 2030 is a crucial part of meeting global climate, biodiversity and sustainable development goals. Protecting tropical forests offers one of the biggest opportunities for climate action in the coming decade.
    • Tropical forests are massive carbon sinks and by investing in their protection, public and private players are likely to stock up on their carbon credits.
    • The LEAF coalition initiative is a step towards concretising the aims and objectives of the Reducing Emissions from Deforestation and Forest Degradation (REDD+) mechanism.
    • REDD+ was created by the United Nations Framework Convention on Climate Change (UNFCCC). It monetised the value of carbon locked up in the tropical forests of most developing countries, thereby propelling these countries to help mitigate climate change.
    • It is a unique initiative as it seeks to help developing countries in battling the double-edged sword of development versus ecological commitment. 
    • The initiative comes at a crucial time. The tropics have lost close to 12.2 million hectares (mha) of tree cover last year according to global estimates released by Global Forest Watch.
    • Of this, a loss of 4.2 mha occurred within humid tropical primary forests alone. It should come as no surprise that most of these lost forests were located in the developing countries of Latin America, Africa and South Asia.
    • Brazil has fared dismally on the parameter of ‘annual primary forest loss’ among all countries. It has lost 1.7 mha of primary forests that are rich storehouse of carbon. India’s estimated loss in 2020 stands at 20.8 kilo hectares.

    Brazil & India 

    • Between 2002-2020, Brazil’s total area of humid primary forest reduced by 7.7 per cent while India’s reduced by 3.4 per cent.
    • Although the loss in India is not as drastic as in Brazil, its position is nevertheless precarious. For India, this loss is equivalent to 951 metric tonnes worth carbon dioxide emissions released in the atmosphere.
    • It is important to draw comparisons between Brazil and India as both countries have adopted a rather lackadaisical attitude towards deforestation-induced climate change. The Brazilian government hardly did anything to control the massive fires that gutted the Amazon rainforest in 2019.
    • It is mostly around May that forest fires peak in India. However, this year India, witnessed massive forest fires in early March in states like Odisha, Uttarakhand, Madhya Pradesh and Mizoram among others.
    • The European Union’s Copernicus Atmospheric Monitoring Service claimed that 0.2 metric tonnes of carbon was emitted in the Uttarakhand forest fires.

    According to the UN-REDD programme, after the energy sector, deforestation accounts for massive carbon emissions — close to 11 per cent — in the atmosphere. Rapid urbanisation and commercialisation of forest produce are the main causes behind rampant deforestation across tropical forests.

    Tribes, Forests and Government

    Disregarding climate change as a valid excuse for the fires, Indian government officials were quick to lay the blame for deforestation on activities of forest dwellers and even labelled them “mischievous elements” and “unwanted elements”.

    Policy makers around the world have emphasised the role of indigenous tribes and local communities in checking deforestation. These communities depend on forests for their survival as well as livelihood. Hence, they understand the need to protect forests. However, by posing legitimate environmental concerns as obstacles to real development, governments of developing countries swiftly avoid protection of forests and rights of forest dwellers.

    For instance, the Government of India has not been forthcoming in recognising the socio-economic, civil, political or even cultural rights of forest dwellers. According to data from the Union Ministry of Tribal Affairs in December, 2020 over 55 per cent of this population has still not been granted either individual or community ownership of their lands.  

    To make matters worse, the government has undertaken systematic and sustained measures to render the landmark Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006 ineffective in its implementation. The Act had sought to legitimise claims of forest dwellers on occupied forest land.

    Various government decisions have seriously undermined the position of indigenous people within India. These include proposing amendments to the obsolete Indian Forest Act, 1927 that give forest officials the power to take away forest dwellers’ rights and to even use firearms with impunity.

    There is also the Supreme Court’s order of February, 2019 directing state governments to evict illegal encroachers of forest land or millions of forest dwellers inhabiting forests since generations as a measure to conserve wildlife. Finally, there is the lack of data on novel coronavirus disease (COVID-19) deaths among the forest dwelling population;

    Tardy administration, insufficient supervision, apathetic attitude and a lack of political intent defeat the cause of forest dwelling populations in India, thereby directly affecting efforts at arresting deforestation.

    Way Forward

    • Implementation of the LEAF Coalition plan will help pump in fresh rigour among developing countries like India, that are reluctant to recognise the contributions of their forest dwelling populations in mitigating climate change.
    • With the deadline for proposal submission fast approaching, India needs to act swiftly on a revised strategy.
    • Although India has pledged to carry out its REDD+ commitments, it is impossible to do so without seeking knowledge from its forest dwelling population.

    Tuntiak Katan, a global indigenous leader from Ecuador and general coordinator of the Global Alliance of Territorial Communities, aptly indicated the next steps at the Climate Summit:

    “The first step is recognition of land rights. The second step is the recognition of the contributions of local communities and indigenous communities, meaning the contributions of indigenous peoples.We also need recognition of traditional knowledge practices in order to fight climate change”

    Perhaps India can begin by taking the first step.