It seems that the Northern California “green” culture is rather different than the L.A.-based Southern California lifestyle. Where would the dividing line between the two be located? Are their outlying islands of either culture? And are there other geographically identifiable cultures in California?
Well, I think the state is pretty clearly divided right about King City on Hwy 101 over to Visalia in the Central Valley.
I think California is really divided into more groups then that; Northern California, Eastern Sierra, Central Valley, Central Coast, Southern California, Mojave Desert. Northern California is from King City North or Monterey if you’re looking for a city you’ve heard of, it stops just east of Sacramento and goes up to the Oregon border. The eastern Sierra takes up the north Eastern part of the state and is basically the good ski towns but is sparsely populated. The Central Valley boils down to Fresno and Bakersfield. The Central Coast is San Luis Obispo, Santa Barbara, and Ventura County the culture here is much more laid back then their brethren to the south. Southern California is from Oxnard (northern most tip of LA in my opinion) south along the coast and is pretty much exactly what you think. The Mojave is the southern part of the Eastern Sierras in my mind bound by Barstow to the Northwest.
But I think every one divides the state up differently in their mind, as far as sub regions but I don’t too many will argue with my north/south line.
If you are looking for a simple line to split cultural SoCal from NorCal, I would say it is roughly the Tehachapi Mountains. Looking at a map of counties, the dividing line would be the northern border of SLO, Kern, and San Bernardino Counties. It’s more of a cultural divide than a 50-50 geographic split.
This puts Bakersfield in an odd spot. If push came to shove, would folks in Bako consider themselves SoCal or NorCal? Fresno?
I can’t imagine Monterey and Sac as the division. That’s too far north unless you live in the Mt. Shasta area.
There are many ways to carve up California. If you want a simple 3-way split that includes Central California, then I would say Central California includes Monterey, SLO, and Ventura Counties, going roughly east from there. Maybe Santa Cruz County… maybe.
You could divide the state even more if you wanted… Mohave, Sierra, Central Valley, Shasta, South Coast, North Coast, Delta, Bay Area, etc. The Central Valley can be split into the Sacramento Valley and San Joaquin Valley. The Sierras can be divided into north and south, too, and maybe even east and west.
If either North or South, Bakersfieldians would probably consider themselves more So Cal than NorCal, seeing as how we’re only about an 1.5 hour drive away from LA.
In my head there are three Californias: Northern California (where all the hippies live), So Cal (just what you expect SoCal to be) and The Central Valley (where all the farmers/Republicans are).
Randmcnally
Born and raised in Bakersfield, although I do try to forget sometimes.
When I lived in Santa Cruz, we felt like we were on some sort of border. To the north was definitely Bay Area (and Northern California in general- the parts North of Sacramento got lumped into “doesn’t exist” California) and yet south of us was the nebulous space between Northern and Southern California (which seemed to start in earnest around Santa Barbara.) If push comes to shove I’d lump central California in with the North.
Every year at UC Santa Cruz there were fights among the incoming freshman (split equally among the Californias), primary about the use of the word “hella”, which is basic vocabulary to a Northerner and a horrible obscenity (so it would seem) to those from the Southern reaches.
In short there is a split and it is hard to pinpoint. Furthermore, in a state bigger than many countries and with an almost unheard of geographic diversity (desert! mountains! beaches! plains!) there are a number of smaller subcultures.
Q: How many NorCalers does it take to change a light bulb?
A: Hella.
The basic problem is that neither NorCal or SoCal wants either place. 
Sorry, I forgot Santa Barbara County
Carmel is definitely Northern, and San Luis Obispo (not to mention Santa Barbara) is definitely southern. I’d agree that King City is a reasonable dividing point. I also agree that the Central Valley is not either. Different climate, different occupation, and different politics.
Looking at a map, I guess King City and the northern border of SLO county aren’t that far apart.
Ain’t that the truth.
I vote for Bakersfield in Southern CA, and Santa Barbara is the starting point on the coast. SLO and the rest of the Central Coast is just very different.
I live way up north, so even the Bay Area doesn’t feel like Northern CA to me.
Yeah, I think of it basically this way too, in a broad brush sense. However, I was very pleasantly surprised when I came to San Diego to actually live…in our little neighborhood there are several cool cafes, bars (I don’t actually go to bars, but I’m just saying), used bookstores, African stores and people, yoga places, good restaurants, and other cool funkiness that defied my perception of So Cal as fake-y, suntanny, suburban-sprawlish hell. And there are a good number of neighborhoods like this.
OB?
Well, Ventura is just across a river from Oxnard, and is farther along the 101, so I think most people would redraw that boundary to include Ventura, at least. You can leave out Carpinteria if you like.
Yep. SoCal can be a very cool place, if you know where to look.
ETA- and yeah, include Ventura in SoCal, since it’s mentioned in a Beach Boys song… 
Living in Santa Cruz I say the northern Monterey Bay area.
I see where your coming from but except for the hill going into LA, there are no breaks between Oxnard and LA. Also they still barbque Tri-tip in Ventura which is a clear sign that you’re still on the Central Coast.
I think the dividing line is really between those who don’t like L.A. because it’s too freaking big and… well… the system breaks down after that.
The ever-enthusiastic Huell Howser did an interesting “California’s Gold” episode with a similar topic:
He also did some shows in search of the furthest “edges” of the state. If you haven’t ever seen the show, and are interested in finding out about the sights, culture, and history of the Golden State, it is well worth checking out.
Me: I divide California into the “redwood” half, and the “desert” half.