For the last four years, California has been in a severe drought resulting in record-high temperatures and record-low snow packs. Our state is lacking an alarming amount of water and our trees are starting to be affected.
The National Oceanic and Atmospheric Administration (NOAA) has declared that it is very likely that an El Niño will happen within the next few months, and it will probably cause a significant increase in the amount of rainfall in Southern California.
“[El Niños] are caused by a series of complicated interactions between the ocean and atmosphere in the tropical Pacific,” Joel Michaelsen, a climatologist and professor in the Department of Geography at UCSB, said.
So what should be expected in the next few months?
“Periods of heavy rain probably starting around mid-January or early February,” Michaelsen said. “The rainy spells typically last two to three weeks at a time, with rain several days per week. There will probably be some flooding, at least of small streams, and some mud slides.”
Even with the increase in rainfall, it still won’t be enough to save many of the oak and pine trees here in California. We need a steady income of rain throughout the years so the soil will stay moist for longer periods of time.
“Certainly, our oak woodlands would benefit from a wet year that replenishes deep soil water reservoirs. But don’t expect oaks to recover overnight from such a deep drought. It could take many years,” the director of UCSB’s National Center for Ecological Analysis and Synthesis (NCEAS) Frank Davis said.
Oak trees are generally extremely tough and able to handle hot, dry weather with little to no precipitation, but the severity of this drought is causing these tough trees to dry out. Additionally, bark beetles, insects that survive very well in droughts, are taking over the pine trees and destroying them at rapid rates.
Davis explained what is happening with our oaks and pines.
“Pines stressed by drought may be more susceptible to attack by bark beetles, especially when beetle populations are not knocked back by cold winter temperatures. And many pines are sensitive to whether water is delivered by snowmelt or rainfall,” Davis said. “Oaks are highly adapted our dry climate, but some may be better able to cope with long-term drought than others. Deeper rooter species may fare better than shallow rooted species. And younger individuals of the species may be more vulnerable than older individuals with deeper more extensive root systems,” Davis said.
The high temperatures we are experiencing are causing our soils to dry out, making it very difficult for trees to receive the water and nutrients they need to survive.
Climate change is not only affecting California, but also areas all around the world. Michaelsen shared his thoughts on climate change.
“[Climate change] is already producing measurable effects that will become much larger over the next few decades. Unfortunately, it is not currently possible to predict with much accuracy how these changes will play out on regional and smaller scales, so there will be many surprises. It is likely that droughts in California will become more severe, although uncertain if they will become more frequent,” Michaelsen said.
In a study conducted by students of Yale University, 79% of Californians think climate change is occurring compared to the national average of 63%. This could possibly be because Californians are experiencing the most effects of warming temperatures, including water scarcity. Because climate change is a slow, gradual process and many areas in the United States have not yet been as critically affected, Americans have not yet experienced the radical change they need to help recognize and combat these effects.
“Recent historical climate change is a fact, not a theory. But our ability to predict future climates is still far from perfect. Given our reliance on California’s incredibly diverse and productive ecosystems, I think we should do what we can to mitigate and adapt to human-caused climate change. California is a global leader on both fronts,” Davis said.
So while the rainfall that California will experience will be beneficial, the damage from these four years of drought have been too expansive and intense to allow for our trees to be healthy again.