(Santa Barbara, Calif.) The fog comes in, and a drop of water forms on a pine needle, rolls down the needle, and falls to the forest floor. The process is repeated over and over, on each pine needle of every tree in a forest of Bishop pines on Santa Cruz Island, off the coast of Santa Barbara. That fog drip helps the entire forest ecosystem stay alive.
Thousands of years ago, in cooler and wetter times, Bishop pine trees are thought to have proliferated along the West Coast of the U.S. and Mexico. Now, stratus clouds the low-altitude clouds known locally as "June gloom" help keep the trees growing on Santa Cruz Island, Santa Rosa Island, and on one island off Baja California. Other than these locations, Bishop pine trees grow only farther north in California where it is cooler and wetter.
Mariah S. Carbone, first author of a new paper, titled "Cloud Shading and Fog Drip Influence the Metabolism of a Coastal Pine Ecosystem," and her co-authors, studied the influence of clouds on the largest Bishop pine forest of Santa Cruz Island. Carbone is a postdoctoral fellow with UC Santa Barbara's National Center for Ecological Analysis and Synthesis (NCEAS). Their study was published in the journal Global Change Biology.
"When people think about climate change, they're often thinking about temperature and precipitation," said Carbone. "When you think about precipitation, it's rain and snow, depending on where you are. What this study showed is that you can have really important water inputs coming from clouds that influence the carbon cycle."
She explained that clouds are one of the largest uncertainties in global climate, and that the forest ecosystem interactions with clouds have a large impact one that has rarely been studied before, particularly in Southern California.
Changes in cloudiness or cloud height with global warming will alter the types of forest ecosystems that grow in coastal California, explained Car
|Contact: Gail Gallessich|
University of California - Santa Barbara