Study Says Climate Models Miss 80% of Drivers Behind Rising Plant Carbon Uptake
Updated
Updated · JNS.org · Jun 12
Study Says Climate Models Miss 80% of Drivers Behind Rising Plant Carbon Uptake
1 articles · Updated · JNS.org · Jun 12
Summary
Less than 20% of the global rise in maximum plant carbon uptake came from higher optimal photosynthesis temperatures, challenging a core assumption used in many climate models.
Data from 2000 to 2019 showed ecosystems absorbed more carbon mainly through better water-use efficiency and expanded leaf cover, while the best temperature for photosynthesis changed little, especially in dry and cold regions.
Plants now absorb about a quarter of human-caused CO2 emissions, so misreading those mechanisms could skew forecasts of how much land ecosystems can keep slowing warming.
The findings also raise questions for carbon-offset projects that assume forests will keep absorbing carbon at set rates, because drought risk and long-term water availability may be bigger constraints than models assume.
If plants' carbon absorption depends on water, are billions in carbon-offset projects now at risk from future droughts?
Climate models got plant behavior wrong. What other critical assumptions about our planet's future might be dangerously inaccurate?
Is nature's enhanced carbon uptake a sign of resilience or a final surge before a climate-driven ecosystem collapse?
Rethinking Plant Carbon Uptake: Water-Use Efficiency and Canopy Growth as Key Drivers for Climate Policy and Modeling
Overview
Recent scientific research has revealed that improved water-use efficiency and increased canopy growth are the main drivers behind the rise in plant carbon uptake, challenging the long-held belief that temperature adaptation is the key factor. Plants are now better at using available water, which allows them to maintain higher rates of photosynthesis even as environmental conditions change. At the same time, larger and denser canopies provide more surface area for absorbing carbon dioxide. These findings highlight that climate models must be updated to reflect these true drivers, as missing them can lead to inaccurate predictions about how much natural vegetation can help slow global warming.