SINGAPORE - In a bid to protect the tropical forests of the world, American Topher White has scaled the trees from Cameroon to Sumatra with gadgets and gizmos aplenty.
In this photo, he is dangling high in the rainforest canopy in Cameroon. But he is not there for the bird's eye view.
It is sound he is after - and the solar-powered sensors he installs on the tree-tops that will help him eavesdrop on the forest and the threats that confront it.
The tropical forest can be an assault to the senses.
The air is laden with strong scents, and the bright colours of flora and fauna are distracting.
Above all, it is hard to miss the hum of life.
This is what a healthy rainforest in west Sumatra sounds like.
Sometimes, however, the forest orchestra is interrupted by uninvited guests. Listen out for the sounds of their interruption at the 50 second mark in this next clip.
It may be clear in the clip, but surrounded by the cacophony of the forest-dwelling creatures, rangers or forest protectors can easily miss the low growl of the chainsaw or the sound of vehicles carrying poachers into the forest belly.
Yet what the human ear misses, technology will not, at least that is what Mr White, 39, is banking on to help save Earth's natural carbon sinks from the axe (or the saw.).
In 2013, he founded Rainforest Connection - a non-profit organisation that creates acoustic monitoring systems to help communities detect illegal deforestation in real-time.
The system works this way: A network of sensors mounted high on trees continuously transmit the forest soundscape via a cellular or satellite network to its "brain" - a computer algorithm developed by Rainforest Connection to detect the sounds of threats.
There is nowhere to plug these sensors in, so each one is powered by array of solar panels arranged like petals of a flower.
"Protecting forests is necessary if we are to fight or reverse climate change," said Mr White, speaking virtually in September at the Ecosperity Week sustainability conference in Singapore convened by state investor Temasek.
"It is these (forest guardians) out there who can do the most - and it becomes our responsibility to build technological solutions for them."
While some forests are protected by rangers, others rely on the communities that live in and around them. These villagers are informally called forest guardians or protectors.
After installing the sensors, Mr White also trains villagers to use the system on their mobile phones.
If the system detects a threat, an alert is sent to a mobile application, which forest protectors in the field can review on their devices and respond in real-time.
The appeal of using tech for conservation
Earlier this year, Singapore announced plans for Climate Impact X - a global carbon exchange and marketplace where "high-quality" carbon credits can be traded.
But Mr Frederick Teo, managing director of sustainable solutions at Temasek said there were challenges at scaling up such nature-based projects.
"The monitoring and verification process for nature-based projects today often rely on infrequent and manual auditing," he said. "There is also limited transparency around the level of impact and potential risks associated with different projects."
But technological solutions, such as the one offered by Rainforest Connection, can help ensure that these biodiversity treasure troves remain standing - for wildlife, and for people too.
Listening to more than forests
The non-profit's acoustics monitoring solution is in use in over 18 countries, including forests in Indonesia and even underwater off Vancouver's coasts, to monitor the activity of whales, dolphins and porpoises.
In this clip, the technology picked up the sound of a travelling pod of orcas near Vancouver.
Speaking to The Straits Times over a video call from San Francisco in September, Mr White said his team is continuously "training" the algorithm to recognise a whole variety of sounds.
More than just the sounds of chainsaws or passing ships, Rainforest Connection is also working with wildlife scientists to build a repository of animal calls.
"Our technology protects forests through avoided deforestation, but other than that, it also showcases the co-benefits of forest preservation," said Mr White.
He cited less tangible aspects such as biodiversity preservation and community involvement which may be of interest to investors looking to put their money into forest conservation projects.
An accelerator for green tech
The Californian start-up was one of five firms shortlisted earlier this year for the Sustaintech Xcelerator - a six-month programme focusing on increasing confidence in carbon credits from nature-based solutions.
The programme is an initiative of DBS bank, Google Cloud, the Centre for Nature-based Climate Solutions at the National University of Singapore, Temasek, Verra, and the World Bank.
The other four - Treevia, Farm-Trace, Cloud Agronomics and Sylvera - also use technology to improve the monitoring or verification of nature-based solutions, such as using artificial intelligence to quantify the amount of carbon locked up in soil.
The five finalists were shortlisted from over 200 applications and were each given resources such as a $50,000 grant. They also had the chance to showcase their work at events, such as at Ecosperity Week.
Mr Teo said the Sustaintech Xcelerator aims to improve nature-based solutions verification and improve investor confidence in such projects.
Projects that have verifiable biodiversity and social impact - such as protecting critical species or benefiting rural communities that support natural ecosystems - have the potential to be traded as "high-quality" carbon credits on the voluntary carbon market, he said.
This is provided that they are also able to deliver emissions reductions that are real, permanent, additional, without leakage and without double counting.
"Climate Impact X is constantly exploring technology partnerships to improve the trust and credibility of the high-quality carbon credits that are traded on its platforms," he said, adding that details on potential partnerships will be unveiled later.