Environmental scientists have new tools for monitoring the health of northern forests — and they’re orbiting many miles above Earth.
Using sensor data collected by satellites, scientists have developed an index to track photosynthesis in evergreens, revealing subtle natural rhythms and seasonal cycles that signal how these trees adapt to climate change.
“Past satellite studies have focused primarily on using ‘greenness’ indices … as indicators of seasonally photosynthetic activity,” project lead Dr. John Gamon told Digital Trends. “While these approaches work well for some types of vegetation, they work poorly in evergreens that lack large seasonal changes in green leaf display — after all, they are ‘evergreen!’”
To see these hidden rhythms on a large scale, Gamon and his team used new combinations of satellite frequency bands, including one that NASA uses to study oceans and one that tracks what Gamon calls the “invisible glow” of chlorophyll. They then developed an index to analyze the changes.
“Satellites are now starting to have the right tools for the job,” Gamon said. “This understanding of how these things are connected in a coherent way depends not only on new satellite data but on a network of collaborating scientists and field sites … and involves a lot of on-the-ground validation.”
Virtually all life on Earth depends on photosynthesis in some way so it is a vital sign of the planet’s overall health.
“Besides releasing oxygen,” Gamon said, “photosynthesis helps regulate our atmosphere by absorbing carbon dioxide … which helps regulate our climate and slow down climate change.” The process also helps humidify Earth by releasing water vapor. “In a warming world, active photosynthesis means a productive world and a more stable climate, which are all indicators of planetary health,” he added.
Slowing photosynthesis, meanwhile, indicates something in the system is failing, Gamon said. It is important then to keep track of even the subtle pigment changes in evergreens, which are particularly telling because they occupy 14 percent of all land on Earth and significantly impact environmental productivity.
“As an example of ‘ill health’ conveyed by evergreen photosynthesis, the recent declines of evergreen forests in much of the western U.S. and Canada due to warming, drought, insects, and wildfire are all indicators of severe stress and can be seen as a decline in planetary health in the face of changing climate,” Gamon said. “In this way, forest activity is a key indicator of planetary health.”
Gamon is now focused on analyzing these changes in photosynthesis detected with the new tools and index in an effort to determine how these vital systems will respond to a changing climate. His study appeared in the journal Proceedings of the National Academy of Sciences this week.
In the broad context of AI and its perceived harms, health and medical risks often pop up in the conversation. The warnings even come from frontier AI labs, such as ChatGPT-maker OpenAI and Anthropic, both of which have warned about misusing AI to cook up bioweapons. Security experts have already spotted a few such incidents in the wild, especially with the usage of AI models without any solid guardrails.
Well, it appears that the risks run deeper. As per an analysis appearing in the British Medical Journal (BMJ), AI bots are now being deployed to influence public policies governing health risks to citizens. In this instance, an attempt was made using AI bots to thwart regulations that aim to restrict the sale of disposable vapes, all while disguising the manipulation efforts as a response from real humans.
What if checking your drinking water for dangerous chemicals were as simple as plugging a tiny gadget into your smartphone? Researchers in Japan have developed a compact sensor that could make that possible, potentially bringing sophisticated water contamination testing out of expensive laboratories and into people's hands.
Scientists at the Okinawa Institute of Science and Technology (OIST) have created a portable device capable of detecting extremely low concentrations of PFAS, commonly known as "forever chemicals." The findings were published in the journal Biosensors and Bioelectronics, which demonstrate how an inexpensive sensor and a smartphone could make identifying potentially harmful chemicals in water a lot easier.
Comets probably weren’t reliable couriers for the ingredients that helped life begin on Earth. A new Cambridge-led study found that fragile organic molecules would usually have been destroyed when the comets carrying them struck the surface.
Published in Scientific Reports, the research tracked hydrogen cyanide, a molecule involved in chemistry that can precede life. Rare successful deliveries remain possible, but the simulations offered little support for a steady supply from comets.