Fourth in our intermittent series on climate change in California
The picture is of a dead Ponderosa Pine. The waterfall is Yosemite Falls. The debate is whether bark beetles, drought or climate change caused the tree’s demise. It is a debate we should not be having, and it highlights the divorce within our culture of literate, clear-thinking people from a scientific community that grows a lot of low-hanging thought branches and obscures the forest.
Of course climate change killed this tree. When we speak of climate, we speak of something fixed and indeterminate; a condition or state, if you will. This is as opposed to weather, which consists of events. Consider climate the enabler of weather and natural events such as droughts and beetles — dictionary material.
By definition, climate implies a lengthy time period. This Ponderosa, as a species, has several hundred if not 500 years of potential life. Were it a transplanted sapling from a nursery, we would say a weather or insect event killed it. However, it takes hundreds of years of corresponding destructive force to kill a tree with a 500-year lifespan.
That destructive force is rising forest temperature over a protracted period. The earth warms and hence combusts more readily, as with Yosemite’s tragic Rim Fire. Vegetation stews in increased heat and draws insects, as with bark beetles.
This is not an isolated pine death. Entire mountain slopes in the surrounding Sierra stand brown, with the destructive force no respecter of species. Both Ponderosa and Sugar Pines — another long-lived species — are victimized. An observant tourist notes the orientation — foresters would say “aspect” — of this spectacle. The orientation of those slopes is south and west, toward the Mojave Desert and the hot Central Valley.
Scientists have no instruments capable of measuring conditions 500 years ago. They only have reasoning and instinct, which must be sharpened by immersion in the forests through walking or camping. A reading of John Muir’s The Mountains of California reveals how his glorious paragraphs of nature appreciation are commingled with deductions about the forces behind landscapes and their relation to one another. We lack John Muirs.
Oak trees are supplanting these lost conifers — not succeeding them, which is a natural process; but replacing them, since the conifers represent the climax forest. Muir’s conifers might exist today as stumps within oak woods, proof that a life zone is shifting in elevation. It would only require a forest walk to find out. Then again, that would be too sensible a means to satisfy the conservation organizations who profit from circular thinking.
Meanwhile, I understand that the Yosemite Ponderosa may have been cut by now, ostensibly to protect visitors from windfall. The credit card companies at the gift store also benefit. Who would want to visit a park victimized by climate change? Worse, who wants to admit that the park itself is a mere event within a matrix of millennia and that larger forces govern its very existence?