Forests are the largest and one of the most important ecosystems, which are greatly affected by the effect of climate change. Higher temperatures increase the frequency of wildfires, bring greater insect infestations, and cause floods and droughts. This warning was issued by the U.S. Department of Agriculture in a report released earlier this week.
The report compiled more than 1,000 scientific studies and it is a part of the National Climate Assessment that will be used for managing national forests.
The predictions show that the areas affected by wildfires in the next 25 years will double. According to Dave Cleaves, climate adviser to the chief of the U.S. Forest Service, scientists and managers should pay special attention to the influence of climate change as it presents the biggest threat.
In order to combat forest fires, the federal government has already spent $1 billion dollars. In addition, insect infestations have also become larger and have killed millions of acres of trees.
James Vose, the report’s lead author, and a forest service scientist, is certain that warmer temperatures will speed up the growth of trees in wetter areas in the East, but will have the opposite effect on vegetation in drier areas of the West. In order to adapt to the changes, tree species will have to move to higher elevations or simply disappear. Erosion and flooding are also expected to increase in severity. Sedimentation might cause disappearance of some stream fish species.
Statistics show that currently the U.S. forests store 13% of the carbon generated by burning of fossil fuels, which means that saving the trees should be of high importance.
Some scientists opposed to the report including Beverly Law, professor of global change forest science at Oregon State University, who stated that her research in Oregon showed that despite more fire, the amount of carbon stored in forests continues to increase. In addition, Tara Hudiburg, a postdoctoral researcher at the University of Illinois, believes there is little conclusive evidence that burning trees for bioenergy helps reduce overall carbon emissions- something that was also suggested in the report. Another strong opinion is that of Andy Stahl of Forest Service Employees for Environmental Ethics, who stated that the agency traditionally has been guided by political pressures, and he has seen no evidence that climate change determines decisions.
But Cleaves is convinced that the threat of flooding is high and climate coordinators should be placed at every national forest across the country.
The report also says that privately owned timberlands would be much quicker to react to market pressures due to global warming than the national forests.