A recent analysis of U.S. Forest Service data reveals alarming trends in the health of U.S. forests, particularly in the Western regions, as climate change takes a toll on their ability to serve as vital carbon sinks.
Led by UF Biology researchers J. Aaron Hogan and Jeremy W. Lichstein, the study published in the Proceedings of the National Academy of Sciences underscores regional disparities in forest productivity. Over the past two decades, the Western U.S. has experienced a significant slowdown in productivity, while the Eastern U.S. has seen slightly accelerated growth.
Forests, critical in regulating the Earth’s climate, sequester approximately 25% of human carbon emissions annually. However, the delicate balance between positive and negative climate change effects is jeopardizing their carbon-storing capacity.
The study challenges assumptions about carbon storage, revealing that extreme climate effects in the Western U.S. overshadow positive growth trends. It suggests that future climate projections may be too optimistic, with ecosystems likely to store less carbon, contributing to more warming and accelerating climate change.
Climate change is not a uniform force, but a dynamic agent with region-specific influences. The study illustrates how the degree of climate change can push forests past a tipping point, making them sources of carbon rather than sinks.
The decline in productivity in Western U.S. forests is not solely attributed to increased tree mortality from wildfires but is significantly linked to declining tree growth rates. Urgent action to reduce human greenhouse gas emissions is crucial to prevent further weakening of carbon sinks in Western forests.
The researchers emphasize the need for reduced global greenhouse gas emissions to restore the global carbon balance and limit the acceleration of climate change. Governments and industries are urged to collaborate for forest conservation and emissions reduction, emphasizing the critical role forests play in addressing the climate crisis.
