Trees in California are most affected

Feb 16, 2010 10:03 GMT  ·  By

According to a new scientific investigation, the amount of fog surrounding redwoods in California, on the West Coast of the United States, has been declining steadily for the past century. The new data, which were obtained from the US National Climate Data Center, paint a bleak future for these trees. They are very beautiful and old, but susceptible to changes in their ecosystems. Investigators believe that dwindling amount of fog could be endangering the trees to a point where the situation may require human intervention, the BBC News reports.

“Fog prevents water loss from redwoods in summer and is really important for the tree and the forest,” explains University of California in Berkeley (UCB) researcher professor Todd Dawson. He is also the coauthor of a new scientific investigation on the issue, which appears in the latest issue of the respected journal Proceedings of the National Academy of Sciences (PNAS). The initial research was focused on determining how the amount of fog on the coast related to the “symptoms” of climate change and global warming. While investigating this connection, team members noticed that records showed a considerable drop in fog, including in areas covered by redwood.

One of the main reasons why redwood grow along the coast, researchers say, is the fact that these trees have yet to adapt to living in the hot summers that are a hallmark of California. Therefore, they need the moisture and relatively cool temperatures that are brought on by fog. The local climate forming in the redwood forests is precisely what these trees need to endure, and without them, they may be doomed, experts say. UCB expert Dr James Johnstone was the leader of the team that conducted the investigation, looking at tree rings to determine whether less fog had an effect on the trees.

“The evidence that you see in the tree rings is consistent with drought stress produced by drought reduction. We're concerned for certain, we expect some impact on the ecology but we don't have clear evidence that the redwoods are about to go extinct in the near term. We need further analysis to find out whether the effects are as we expect,” he concludes.