How deforestation can be stopped is a central theme at the ongoing UN Climate Conference (COP30), which is being held in the Amazon, to drive home the importance of rainforests in arresting climate change, according to Brazilian president Lula da Silva.
But it is important to ask: where are these most critical ecosystems? A few satellite images can tell us how high and dense rainforest ecosystems are.
The Global Forest Canopy Height tool, with 10m spatial resolution, tells us where the world’s densest and tallest (and often oldest) rainforests are located.
They are in Brazil’s Amazon rainforests, in Africa’s Congo basin, and in parts of Indonesia and Malaysia. In India, they are in the northeast, the Western Ghats and also the Andaman and Nicobar Islands.
The Andaman and Nicobar region has dense forests of canopy height of over 25 to 30m in many regions, similar to the Amazon. What does a 30m canopy height mean? According to a paper published by Nature Ecology and Evolution in Nature journal in 2023: “A high-resolution canopy height model of the Earth”, only 5% of the global landmass is covered by trees taller than 30 m and only 34% of these tall canopies are located within protected areas.
But satellite data has its own limitations. It gives a sense of what is at stake but tends to underrate canopy height and density of rainforests. The Nature study said that canopy height estimation with existing standard tools tends to struggle with the underestimation of tall canopies, as the height estimates saturate around 25 to 30m. This is a fairly severe limitation in regions dominated by tall canopies, such as tropical forests, and deteriorates downstream carbon stock estimation, because tall trees have especially high biomass.
According to Joice Nunes Ferreira, researcher at Embrapa Eastern Amazon, old-growth Amazonian forests are highly species-rich, with a great diversity of large trees and significant environmental and structural heterogeneity. The height of trees in the Amazon can reach up to 60-80m and tree density is more than 500 stems per hectare.
In lowland rainforests, the canopy height can be 40-50m range and 30-40m in lower montane rainforest. HT had reported on October 6 that the density of trees in Great Nicobar may be far higher than understood. It is between 500 to 800 trees per ha, of at least 30cm girth size or larger.
Rainforests are so dense that at times it’s difficult to see the open sky through the canopy, according to ecologists.
“Rainforests in general are almost identical/similar functionally: We have big trees, they have big leaves, most trees belong to a few species there and here, the total number of species is similar. There are also a lot of parallels despite their differences: They have lots of forest palms, we have fewer palms but compensate with climbing canes or/rattan; a lot of the Amazon floods for some time of the year; our rainforests don’t flood as much but a lot of Southeast Asian rainforests sit on perpetually boggy peat swamps,” said Akshay Surendra, an ecologist and wildlife biologist studying tropical forests in the Andaman Islands.
Both the Amazon and Great Nicobar face similar threats. In the Brazilian Amazon, in the most intact areas (western part of the basin), the main threat is climate change, followed by planned road paving projects. Mining also poses a localised threat in certain regions, according to Ferreira. In the Great Nicobar, the government has planned four projects in the region — International Container Transshipment Terminal (ICTT), Greenfield International Airport, Gas and Solar based Power Plant and Township; Area Development Projects — for which an area of 166.10sqkm is required. Of this, forest area is 130.75sqkm.
Of the forest area under the project, tree felling is envisaged in 47.75 sqkm according to Andaman and Nicobar Islands Integrated Development Corporation Limited (ANIIDCO) call for EOI for tree enumeration and felling. The government has said the project is critical from the strategic, national and defence point of view.
Some of this tree felling may affect tall trees, whose loss may take decades to replace. According to a Meta-World Resources Institute global map of tree canopy height — it tells average canopy height at a one metre resolution — around 75% of the island’s area has a canopy height of more than 10 metres, 59% of more than 15 metres, and 33% of more than 20 metres. Around 10% of the island has an average canopy height of over 25 metres. To be sure, like all averages, an average height over even 1sqm is likely to underestimate the tallest trees.
In India’s northeast, forests are at risk from mining, hydropower projects, logging, and agriculture, among others. For example, the Etalin Hydropower Project (3097 MW) on Dri and Talo rivers in Arunachal Pradesh’s Dibang Valley is coming up in a “ high conservation value area.” The project will involve felling of 270,000 trees and diversion of 1,175.03ha of unclassed forest land. And that the area harbours important wildlife including the Himalayan Serow, Asiatic Golden Cat, Leopard Cat, Indian Wild Dog, Assam Macaque, Himalayan Black Bear, Barking Deer, Wild Boar, Hoary Bellied Squirrel, Bengal Monitor Lizard, Burmese Python, and King Cobra.
Rainforests are facing existential threats. This is accentuated by the fact that these forests are home to hundreds of rare, endemic species and indigenous populations.
The Nicobar Islands fall in the Sundaland Biodiversity Hotspot. This region covers the western half of the Indonesian archipelago, a group of some 17,000 islands stretching 5,000km, and is dominated by the islands of Borneo and Sumatra.
For the Shompen, a particularly vulnerable tribal group, these rain forests are foraging ground mainly for food. They take pandan fruits from here apart from other foods that are an integral part of their diet. “Plantations typically contain one or a few tree species, low fauna diversity and are vertically homogeneous. These cannot replace rainforests,” added Ferreira. “Old growth or primary forests are irreplaceable for the diversity of trees themselves, and definitely for other plants and animals that depend on the trees, “ said Surendra.
According to a 2011 paper published by Gibson and co-authors in Nature journal titled “Primary forests are irreplaceable for sustaining tropical biodiversity”, most forms of forest degradation have an overwhelmingly detrimental effect on tropical biodiversity. The results indicated that when it comes to maintaining tropical biodiversity there is no substitute for primary forests. The team conducted a global assessment of the impact of disturbance and land conversion on biodiversity in tropical forests using a meta-analysis of 138 studies.
“In terms of ecology, there is no scenario in which compensatory afforestation can match diverted rainforest land. In the case of Great Nicobar, I would argue that the scale of dissonance is too staggering, too great. For example, the extent of mismatch between Haryana (where compensatory afforestation is taking place) and Great Nicobar in carbon / biodiversity cannot be greater,” Surendra said.
Island rainforest ecosystems are particularly important for the endemic species they harbour.
The Crab-eating Macaque, Nicobar Tree Shrew, Dugong, Nicobar Megapode, Serpent Eagle, saltwater crocodile, marine turtles and Reticulated Python are endemic and/or endangered in GNI.
Brazil launched the Tropical Forest Forever Facility (TFFF) on November 6. The TFFF is an initiative that incentivises the conservation and expansion of tropical forests by making annual payments to Tropical Forest Countries that maintain their standing forests.
It was endorsed by 53 countries with rainforests and those without rainforests on the day of its launch including China, Canada, UAE, Finland, United Kingdom, Japan, Australia to Indonesia, Germany, Antigua and Barbuda, Armenia, Bolivia, Ecuador, Colombia, Democratic Republic of the Congo, Rwanda, and Peru, among others. India has not endorsed the scheme yet according to the list provided by the Brazilian Presidency.
In total, 34 tropical forest countries endorsed the TFFF Declaration, covering over 90% of the tropical forests in developing countries, including Indonesia, the Democratic Republic of Congo and China. India has joined the coalition but only as an “observer.”
The valuation of environmental preservation through the TFFF stems from the understanding that ecosystems such as the Atlantic Forest, the Amazon, and the Congo and Mekong basins are essential to sustaining life, as we know it today.
Experts are not sure if TFFF can help reverse deforestation. The facility’s reliance on private investors makes it vulnerable to financial market volatility, potentially creating unstable funding and a reduced ability to generate capital if returns are perceived as risky.
Tropical forest countries that may become dependent on this funding going forward could get a shortfall where they don’t have funding that they’ve been counting on, and then that contributes to tropical forest loss down the road, some experts have suggested.
Nevertheless, Brazil sees huge potential in TFFF and also sees forests as a major issue at COP30.
“After more than 30 years, after the Earth Summit in Rio, the Climate Convention comes back to the country where it was born. Today, the eyes of the world are now looking towards Belém with great expectation. For the first time in history, a climate COP will take place in the heart of the Amazon. In the global imagination, there is no higher symbol of the environmental cause than the Amazon forest,” Lula said at the Belem Leaders’ Summit earlier this month.
“Here we have thousands of rivers and igarapés that make up the largest hydro basin on the planet. Here live thousands of species of plants and animals that are part of the most diverse biome on the Earth. Here live millions of people and hundreds of indigenous people, where their lives are faced by a false dilemma between prosperity and preservation…So here are the ones that daily, together, they put together the way they live and seeking for existence and livelihood that is legitimate and with dignity and with the main mission to protect one of the highest cultural heritages of humanity, that is nature,” Lula added.
On November 12, more than 200 boats carrying indigenous, riverine, and social movement leaders occupied Guajará Bay, to demand an end to oil drilling in the Amazon and forest diversion, according to Amazon Watch. Chief Raoni Metuktire said at the meeting:“The forest lives because we are here. If they remove the people, the forest will die with them.”
“I can speak for my people (Huni Kuin) and the region where my people live (State of Acre). In Acre, the rivers have become very hot and are contaminated by mining, causing fish to die. Communities have faced difficulties in obtaining food, leading to famine. We have periods of intense drought, and we face floods that cause many inundations where relatives lose agricultural production such as bananas, cassava, and other products for consumption and sale, necessary for the survival of these communities,” said Luciene Kaxinawa, an indigenous journalist from the Kaxinawa tribe from Amazon on the impacts of climate change.
According to Rainforest Foundation Norway and Asia Investor Group on Climate Change (AIGCC) issued on October 20, a group of global investors representing almost USD 3 trillion in assets under management has signed the Belém Investor Statement on Rainforests, calling on governments to adopt and enforce robust policies to halt and reverse deforestation and ecosystem degradation by 2030. The statement urges alignment with international commitments including the COP28 Global Stocktake and the 2021 Glasgow Leaders’ Declaration on Forests and Land Use. While investors acknowledge their responsibility to address commodity-driven deforestation, they emphasise the need for enabling policies that deliver legal, regulatory, and financial certainty in forest-risk sectors.
In 2024 alone, 6.7 million hectares of tropical forest were lost, equivalent to 18 football pitches every minute, undermining climate stability, biodiversity, and economic resilience. This destruction weakens the ecosystem services that underpin global markets, amplifying systemic and financial risks for investors, the statement said.
Further, Brazil has approved the drilling licence for an oil block in the Amazon River basin.
Civil society groups and social movements are taking the case to Brazilian courts, according to a statement by the Fossil Fuel Treaty initiative on October 20.
“The Amazon is dangerously close to the point of no return, which will be irreversibly reached if global warming hits 2°C and deforestation surpasses 20%. Beyond eliminating all deforestation, degradation, and fires in the Amazon, it is urgent to reduce all fossil fuel emissions. There is no justification for any new oil exploration. On the contrary, rapidly phasing out existing fossil fuel operations is essential,” said Carlos Nobre, Co-Chair, The Amazon Scientific Panel in a statement.
India’s extraordinary biodiversity
Within India, tropical rainforests are found in three main regions. One important region is along the Eastern Himalayas in Assam and the hill states (Nagaland, Manipur, Mizoram, Tripura, Meghalaya). The northernmost tropical rainforests on Earth are found at around 28° N along the slopes of the Eastern Himalayas in Arunachal Pradesh. These rainforests are part of two global biodiversity hotspots: Himalaya and Indo-Burma. Another region with tropical rainforests is the Andaman and Nicobar Islands: while the Andamans falls within the Indo-Burma biodiversity hotspot, the Nicobar are unique in their own way and fall within the Sunda Region biodiversity hotspot that extends to Southeast Asia. Finally, tropical rainforests are found in the Western Ghats mountain range along, which is another global biodiversity hotspot. India has parts of four global biodiversity hotspots within the nation’s boundaries and this is mainly because these areas house tropical rainforests, which have extraordinary diversity of species and high levels of endemism, according to TR Shankar Raman, a wildlife scientist.