Right now, in 2015, I know of no one else who is predicting what I'm about to predict: That within 100 years, the part of California currently referred to as Silicon Valley will return to a largely agricultural economy--as it was for a prior 100-year period, roughly between 1860-1960.
On a map, "Silicon Valley" more or less translates into being one and the same with Santa Clara County--an area that, essentially, includes all South (San Francisco) Bay Area cities from Palo Alto to the north, and down to Gilroy in the south. This area includes the large (about 1M population) city of San Jose.
Why will this change, a change that will see the world's most celebrated high-tech Mecca revert back to its agrarian roots, come to pass?
For a few reasons. Firstly, California is drying up. Not only are dozens of current "before and now" photos of the state's once full and flowing lakes, reservoirs, rivers, etc. providing concrete proof of this extreme environmental change: but I see it too from personal experience. The Silicon Valley I left in 2001 (for a 12-year stint in Las Vegas, Nevada) was an area that received plenty of rain, was seemingly blessed with year-round moderate temperatures, and was a place where lush lawns and landscapes were not only encouraged, but often insisted upon by snippety landowners, real estate managers, and Homeowner Associations.
But those days are long gone. Rain is scarce, and many of those same Associations are now encouraging (in fact, some are paying) homeowners to convert those once lush landscapes to...desert landscaping. California has always endured droughts, but nothing on record quite as severe as what's going on here now.
As bleak as this scenario may sound though, the stage is being set for absolutely ideal AG conditions--specifically, for large scale fruit tree production to again flourish in Santa Clara Valley, actually known in years past as "The Valley of Heart's Delight." Those once pesky floods (which sometimes ruined an entire year's crop) have been seemingly replaced by ever more abundant sunshine, critical for abundant plant growth.
Add to that ideal environment some of the planet's most fertile soil, and a burgeoning world population that is currently over 7 billion--and expected (according to one UN estimate) to possibly reach 16 billion by 2100--then it becomes clear that Earth's most fertile lands must be used for AG, in order to most efficiently feed our (mostly) yet-to-be-born 100-year descendants.
Those who are not locals may be skeptical as to just how fertile this land is: So I'll offer an example. Last year I bought a dwarf D'Anjou pear tree and planted it my backyard--as a sort of tribute to the vast pear orchard that, up until around the 1960's, once occupied the North San Jose land on which I live. Typically, pear trees require two specimens in order to thrive, to cross-pollinate; however, I only planted the one. I rarely water it. In fact, I may have watered it three, maybe four times during this entire last winter. Yet sure enough, it was loaded with blooms last month and has now sprouted dozens of tiny green pears. So many, that I am having a difficult time imagining how that modest tree of about 6 feet tall is going to endure the August/September weight of all that mature fruit.
The fact that California is slowly drying up further adds to my hypothesis. Decades ago, when the states's large scale AG production shifted from this valley to the state's Central Valley, irrigation was thought to be the cure-all to counter that area's known arid conditions. After all, rainfall to the north would always be plentiful, right? Sadly for us, wrong.
This prediction is not necessarily bad, nor good--but it will come to pass. Feeding the world's massive population in the year 2115 will require doing so in the most efficient ways possible. Dry conditions and average quality soil (such as those which exist in the Central Valley) simply won't suffice in the not-too-distant future. Drive out that way sometime this summer and you'll see billboards which flat-out declare the current state of their "Congress Created Dust Bowl." Or, just think of that tiny, solitary--neglected, even--pear tree that's currently thriving in my backyard.