Recent studies have noticed a strong positive correlation between the concentration of nitrogen in forests and infrared reflectance measured from aircraft and satellites. Some scientists have suggested this demonstrates a previously overlooked role for nitrogen in regulating the earth's climate system.
However, a new paper in Proceedings of the National Academy of Sciences, shows that the apparent relationship between leaves' nitrogen levels and infrared reflection is spurious and it is in fact the structure of forest canopies (the spatial arrangement of the leaves) that determines their ability to reflect infrared light.
The authors, including Professor Philip Lewis and Dr Mathias Disney (UCL Geography), show that the richer in nitrogen individual leaves are the worse at reflecting infrared radiation they become. However, the complex arrangements of trees with radically different arrangements of leaves within a forest can act to mask this effect, making it appear as if higher levels of leaf nitrogen are leading to increased infrared reflection.
Dr Disney said: "It is impossible to understand how forests reflect infrared without taking into account the arrangement of different types of leaf clumps, such as shoots and crowns, which make up the canopy, as well as the internal structure of the leaves.
"This paper proposes a way to account for structure when measuring canopy infrared reflectance. We hope it will improve our ability to measure forest biochemistry from satellites, allowing us to better quantify forests' current state and how they are responding to climate change."
University College London: http://www.ucl.ac.uk
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Researchers have combined nighttime satellite imagery with river maps to quantify where people and property are most in danger of flooding.
Wireless network of radars spots poachers who enter a reserve, or tigers leaving in search of cattle and alerts the wardens
The South African government scrambles to thwart illegal killing and save what remains of its threatened rhino population
NASA has created a new, super high-resolution visualization of a year of CO2 swirling around in the atmosphere. The post Striking Animation Shows One Year of CO2 Swirling Through the Atmosphere appeared first on WIRED.
The Green Climate Fund to help poor nations adapt to climate change may reach its initial target of $10 billion by this week's deadline
A new Toyota model could change the way Americans power their cars
A new study found that polar bears numbers have fallen by 40 percent as they struggle to feed themselves
One scientist is tagging hundreds of sharks in Florida in the hopes that their movements could help forecast extreme weather
Iconic species of the Everglades is shrinking and dying off, and scientists are trying to figure out why
Pacific bluefin tuna, Chinese pufferfish, American eels and Chinese cobras named by conservationists as risking extinction due to overfishing