The problems for the new Obama administration keep adding up; in the current issue of the prestigious journal Science, researchers led by the US Geological Society, have noted that forests in the US are dying at an alarming clip. Analysis of old-growth forests have showed that the mortality rate has more than doubled since 1955, and global warming appears to be the main culprit. According to the study, “regional warming and consequent increases in water deficits are the likely contributors in the increase in mortality,” and other possible factors, including insect attacks and pollution, exerted less influence than climate change.
Old growth trees are usually the most hardy and most resistant to stress. If older trees are dying, then younger trees would not be able to withstand the same conditions, and that’s exactly what this study has found. Furthermore, the death rate cuts the widest possible swathe, affecting dozens of species, and working through all elevations.
The scientists noted that this mortality rate will have a huge impact on the forests’ ecology and carbon storage capabilities. “We may only be talking about an annual tree mortality rate changing from 1 percent a year to 2 percent, but over time a lot of small numbers add up,” said co-author Professor Mark Harmon from Oregon State University.
Harmon fears that the die-back is the first sign of a developing “feedback loop” that will lead to more regional warming and a higher tree mortality rate. It hurts in two ways: Fewer living trees will be available to absorb carbon dioxide, and decaying trees will release carbon that had been sequestered for centuries.
Editor’s Note: Back in October, for my day job, I wrote a story about the value we should assign to forests and what they do for our economy. It ran:
Although the Wall Street bailout is garnering headlines around the world, the disappearance of forests and ecosystems carries a far steeper price, according a European Union commissioned study that puts the annual loss at between $2 trillion and $5 trillion US. That figure isn’t arbitrary — it comes from adding together the various services that forests perform, including filtering and purifying water, absorbing carbon dioxide from the atmosphere, and providing food for billions of people.
The study, headed by a Deutsche Bank economist, covers much of the same ground as The Stern Report released in 2006, and provides ammunition for policymakers who want the developed world to do more to slow deforestation in developing countries. It’s called The Economics of Ecosystems and Biodiversity.
Lead author Pavan Sukhdev emphasized that the cost of natural decline dwarfs losses on the financial markets. “It’s not only greater but it’s also continuous, it’s been happening every year, year after year… So whereas Wall Street by various calculations has to date lost, within the financial sector, $1-$1.5 trillion, the reality is that at today’s rate we are losing natural capital of at least between $2 to $5 trillion every year.”
Overall, forestry decline comes with a heavy price tag approaching 7 percent of global GDP. This study is ongoing, and research on its second phase will be collected over the next two years and compiled in a second report to be presented in 2010.