According to the local blogs, news stories and organization newsletters that I read, there is a cohort of people in Nevada County that have adopted the religious mantra that humans are responsible global warming. Our most vocal liberal blogger at Sierra Foothills Report has decided that skeptics of the anthropogenic global warming are idiots but offers no proof, only telling us “some studies have linked climate change to regional drought.” No proof!
Some studies have linked climate change to California droughts. The drought goes well beyond California too — Colorado, New Mexico, Nevada, Kansas, Texas, Arkansas, Hawaii, Idaho, and Oklahoma.
Well, I am a skeptic and have a couple of questions for our local AGW promoters, including our local liberal blogger. CO2 is increasing more rapidly in the 20th and early 21st Century, and is being attributed to causing California’s current drought. OK, then let me ask, what caused California’s strong droughts, longer then 3 years, ending in 983, 1301, 1581, 1778, 1796, 1829 and 1934? All these droughts were before the increases in CO2.
These droughts were identified in the flow of the Sacramento River by studying tree rings in the rivers watershed. In 1580 the annual tree ring growth was missing, the flow was lower than 1.5 million acre feet for the year. The average flow from 1906 to 1999, was 18.1 million acre feet.
What about beyond California? The analysis of a 121-site tree-ring network in the Colorado Basin covering the period from1600-1962. It identified a four year drought in the 1660s, and a much longer and more severe drought in 1579–1598. CO2 was not a problem during these periods, and cannot be responsible for the droughts now, unless we see some proof from our local lefty blogger.
If these historic droughts were before increased CO2, why are the current droughts caused by CO2? What is the proof? I am currently working on some plots of the data from late 800s to the present. Stay tuned.