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Mediterranean vs. sub-Mediterranean
As you might guess I'm trying to narrow down and capture the concept for a book that I may eventually write if I ever have time (maybe I'll have something before I die, LOL). I'm thinking the title may have to include the word 'sub-Mediterranean' (thanks Eric!)
The following thread was started by Ian on March 01, 2009 at 1:04 am PST
some of my impressions---generally, "sub-M" climates tend to have cooler moister winters with a greater frequency of cold temps for longer durations with shorter, cooler summers whose extreme high temps are of shorter duration. the differences can be subtle---medford, oregon is pretty dry and thus similar in winter rainfall to redding, california but its liability to more cold in the winter and less heat in summer would put it out of the "classic-m" that redding enjoys (or endures). gardening wise, you can get by with most of the standard rhododenrons, heathers, etc. of cooler climates fairly easy (using proper siting and watering) in medford but they are much more difficult in redding and similar climates. on the other hand you can grow citrus and date palms in most of the med. areas but in sub areas they are generally not long term out door prospects. my two cents on the subject????
The above followup was added by georgeinbandon,oregon on March 01, 2009 at 8:31 am PST.
"Subtropical" and "subarctic" (literally "under the tropics" and "under the arctic") are reasonable terms because "tropical" and "arctic" are defined by latitudinal bands. Those are climates found just outside the latitudes where the arctic or tropics begin. Mediterranean climates are created by oceans. So how would "under the Mediterranean" make sense?
The above followup was added by Steve in Brookings on March 01, 2009 at 8:36 am PST.
Steve, i would think that the "sub" here means "less than" in a climatic sense rather than geographical location. perhaps "para" (or even "pseudo") in the sense of similar to might be a "better" designation????
The above followup was added by georgeinbandon,oregon on March 01, 2009 at 8:51 am PST.
As far as I know mediterranean climates are defined almost entirely by the yearly pattern of rainfall, with a marked summer drought and moist winters. because this pattern occurs only on the west coasts of continents from around 30 deg north to say 43 or so (it obviously varies from continent to continent) temperatures are usually subtropical - bit they needn't be hot...look at San francisco for example. I think temperature is of secondary importance when classifying a med-type climate, because there's so much variation in this factor.
Personally, I've always thought "west coast temperate with Mediterranean characteristics" best describes our climates in inland/rainshadow areas of the PNW best describes our climate. Arbutus, garry oak, manzanita, etc are certainly well adapted to the med characteristics of our climate. Our main difference is not a lack of summer heat though (because many coastal areas with a med climate like San francisco, northern Portugal, etc have moderate temps as well). Rather I think the difference is that our own drought is less severe even though we're dry in the summer, because our year round insolation is simply too low.
The above followup was added by Dave, Vancouver Island, z8b on March 01, 2009 at 9:52 am PST.
I just re-read my post and noticed the syntax errors. Sorry...I'm typing all this from an iPhone!
The above followup was added by Dave on March 01, 2009 at 9:54 am PST.
If you think of the name for the climate of your area as well as Puget Sound, Southern Gulf Islands and Victoria that's the term that is used in various publications I have seen in BC. The 1959 Soil Survey of Southeast Vancouver Island and Gulf Islands, British Columbia noted that this area is influence by the ‘rain shadow’ effects of the Olympic and Insular Mountains and described the Cool Mediterranean Climate as follows:
The natural environment throughout the Saanich Peninsula and on the adjacent islands is, in many respects, similar to that of much of the northern Mediterranean region. The summer temperatures are somewhat lower but the drought during the summer months is, generally speaking, just as marked. Rainfall for the two-month period, July and August, does not average more than 1.3 inches. Bright sunshine, too, is a feature of the area, particularly adjacent to Victoria where an annual average of 2193 hours is recorded. That is more sunshine than is recorded in any parts of the Province. The oak parkland vegetation and the Black or ‘prairie-like’ soils add further support to the statement that the Saanich Peninsula has a cool Mediterranean type of climate. It is interesting to observe that this represents the farthest poleward advance of a true Mediterranean climate on the earth’s surface.
The Cool Mediterranean Climate then changes to what they call in the publication as Transitional Climatic Type (north of Saanich to Comox) and Maritime Climate on the other side of Insular Mountains (west of the Vancouver Island mountain range).
The above followup was added by Vlad Pomajzl, Saltspring on March 01, 2009 at 2:29 pm PST.
Lots of near-Med climates
You've got the Victoria / Gulf area, the valleys of western Oregon, and even the eastern Columbia Gorge, all of which share some quasi-Mediterranean characteristics: summer drought, winter rain and oak woodlands. While none of them are probably Mediterranean proper, there are enough similarities that a resident of one of these three areas who moved to an appropriate subdivision of the true Med climate would probably feel at least somewhat at home. A Victorian would have little trouble adapting to the weather near San Francisco; a resident of the Willamette Valley would find certain sub-coastal parts of Norcal to be notably familiar, and someone who grew up in The Dalles would feel at home in parts of the Far East Bay or Sacramento area, at least in summer.
The above followup was added by Eric, eugene on March 01, 2009 at 6:05 pm PST.
I'm a CA transplant
I agree with a lot of what everyone is saying. There are many similarities I have found with the Bay area to western Oregon where I lived for 25 years. Everywhere I go down here I find things that remind me of home. I find the climate not all that disimilar with similar temps in the summer but a little warmer in the winter with less rainfall (although not looking at the last 3 weeks where it has rained nonstop!). You also get the occasional warm winter day down here. January had several days in the 70s. The biggest difference is the scarcity of arctic events and big freezes. My low for this winter was 34F. One of my tomatoes that is protected from the roof overhang is even still alive from last summer. the wooded areas along the western santa clara valley look almost identical to the forest flora that I was used to in Oregon just replace Redwoods with Douglas Fir. Climate has been the easiest transition. Getting used to the giant urban sprawl mess that is the city of San Jose has been quite an adjustment but I don't need to get started on that.
The above followup was added by Eric, San Jose CA z9b on March 02, 2009 at 8:00 am PST.
shades of Med
Dave put his finger on the issue. Mediterranean climates are defined by a precipitation pattern. We might make certain assumptions about thermal characteristics, but they might not hold true throughout the range of Med climates. The term "Mediterranean" describes a family of climates that includes USDA Zones ranging from 7 to 11. It includes coastal climates that are relatively homeothermic (not much thermal change from winter to summer) as well as inland and valley climates that are relatively heterothermic (summer is markedly warmer than winter). Within these two categories, Med climates differ by how high or low the average annual temperature is. San Francisco would be an example of a cool homeothermic Med. climate. A warm homeothermic Med. climate would be San Diego. Medford would be an example of a cool heterothermic Med. climate and Fresno would be a warm heterothermic climate.
It seems to me that there are three characteristics that make a winter-rainfall climate "less Mediterranean," if you will:
1. Average annual total rainfall above 700mm
2. Cool summers
3. Cold winters
One way of illustrating this (based on the familiar soil composition triangle), would be with a nested set of concentric equilateral triangles. The vertices of the triangle would be labeled as above. In the very center of the triangle would be climates like those of Cape Town, Syndey or Los Angeles that have none of the "diminishing criteria" listed. They are classic Mediterranean climates: they have a winter rainfall peak, but low annual rainfall --soil moisture is exhausted by mid-summer. They are relatively cool to mild in winter; frosts are rare, but not unheard of. They get warm in summer, but scorching desert-like conditions only occur during heat streaks.
Outside of this central triangle of classic Med. climate would be those climates that show greater heterothermy: Sacramento, Redding, Bakersfield. One more level out and moving toward a vertex would be climates that show a strong diminishing criterion like Medford (vertex 3 - cold winters) and San Francisco (vertex 2 - cool summers). In the outlying triangle, we might find cities like Portland and Seattle -- places that have Med. tendencies, but show at least two diminishing criteria (cool summers and high annual rainfall in this case) and cannot therefore really be called "Mediterranean climates" overall even though they show a Med precipitation cycle and many Med plants will perform adequately there.
Horticulturally, Med climates are often identified by their amenability to the culture of Mediterranean fruits and nuts. The classic four are: fig, olive, grape, and pomegranate. In a true Med climate, these should grow easily. Mandarin, persimmon, pistachio and almond are sometimes included as well, though they did not actually arise in the Mediterranean basin.
The above followup was added by Steve in Brookings on March 02, 2009 at 1:58 pm PST.
According to Koppen, I live in climate Csa, and much of the PNW is Csb classification. This is consistent with a classification of "Mediterranean".
Still, there are other things to keep in mind, like Steve mentioned. Does one look at evaporation vs precipitation, or xerophytic / indicator plants? For what it's worth, I'm confident that I live in a "cold winter" Mediterranean climate here in Southern Oregon. We get around 18-19" of rain in an entire year, with almost all of that falling between October to May.
The local forcasters are happy to say it will rain, something I rarely heard on the news living in Corvallis. (Steve, you can relate, you get Medford stations in Brookings).
Here are a few links that describe So.Or. as "Mediterranean" (just for fun). This is the main reason I moved down here!!! :)
Pic I've posted before, near my house in Talent, OR.
The above followup was added by Brenton on March 02, 2009 at 8:11 pm PST.
Brenton: Looks just like The Dalles
...well almost at least. I guess you could say that the eastern Gorge would be an "icy winter" Mediterranean climate, even if it's not icy all the time during the winter months.
The above followup was added by Eric, Eugene on March 02, 2009 at 9:45 pm PST.
The oaks in The Dalles / Gorge would be Q. garryana, while the deciduous oaks down here are heavily Q. kellogii.
I love the look of the landcape around Arlington and etc! If I lived in PDX, I'd go over there often for that semi-arid landscape!
The above followup was added by Brenton on March 02, 2009 at 10:16 pm PST.
Arlington almost looks a little too dry and barren...and the landscape starts to get flatter and flatter the further east you go. Well I guess the arid flatlands are interesting in their own way, and it gets much nicer towards Pendleton and beyond. It's worth going through there every once in a while. As for culture, economy/job opportunities and politics however, no thanks.
The above followup was added by Eric, Eugene on March 02, 2009 at 11:05 pm PST.
Have you ever been to Walla Walla, a bit farther up the gorge, Eric? That is a nice town. A mix of green valley and arid slopes. Lots of sunshine. Progressive people who appreciate culture, lots of wineries and art studios. Nice scenery, good hiking opportunities. It gets cold in winter but the growing season is longer than Portland's. Only problem is that it is rather isolated.
The above followup was added by Steve in Brookings on March 03, 2009 at 8:54 am PST.
Seems like everyone has slightly differing, but frequently overlapping perspectives on this one. Defining a Mediterranean climate by wet winters/dry summers alone doesn't quite work for me - although it is perhaps the most significant factor. There needs to be some temperature criteria involved.... that or else 'if you can grow X then you're in a Mediterranean climate' (P. canariensis? Arbutus unedo?). The problem with not having a temperature criteria is then you have places like Winthrop, WA as a Mediterranean climate where the all time low is -48F. You have to cut it off somewhere. Steve I suppose you might have meant Perth not Sydney.
So I've got a concept for the category of plants I want to write about but I'm just not sure what to call it. 'Sub-Mediterranean' almost works but it could be confusing. 'Para-Mediterranean' almost seems more appropriate but even more off the wall as far as inventing new terms. Some of you who are interested in the same plants as me have hit the concept on the head but it took a paragraph or so to do it. Sort of a western/maritime/Mediterranean/exotic/xeric mix. How can I put all that into one word?
The above followup was added by Ian on March 03, 2009 at 9:55 am PST.
Ian, you might just have a designation of "mediterranean like" (or even "med-LITE" LOL)---described as cliamtes with similar patterns of winter wet/summer drought but with either cooler winters or cooler.wetter summers (ror a combination of all the above). indicator plants for "classic" med climates would include olives, date palms, canary island palm, citrus, oleander. the med-like climates could cultivate a number of "med-native" (italian cypress, holm oak, strawberry tree, rosemary, med fan palm, fig) or plants with similar needs like our "native" madrone/arbutus, canyon live oak, manzanita,, ponderosa, coulter, and digger pine, etc. etc.
The above followup was added by georgeinbandon,oregon on March 03, 2009 at 10:25 am PST.
Wow, those oak-covered hills around Talent truly look classically Mediterranean. I'd have no problem/hesitation whatsoever classifying your part of Oregon as having a "med-type" climate. Even though it can occasionally get cold in the winter in your parts, don't forget that the actual Med basin itself in southern Europe is also sometimes subject to cold blasts (Marseilles, France has hit -17C in the past, for instance).
Other PNW places that really LOOK Mediterranean to me (aside from southern Oregon's valleys) are the southern Gulf Islands and San Juan Islands, some parts around Victoria and the Olympic peninsula that lie under direct influence of the rainshadow.
The above followup was added by Dave, Vancouver Island, z8b on March 03, 2009 at 3:14 pm PST.
Wikipedia: Mediterranean climate
here's an excerpt from the Wiki (including a section that I myself wrote!):
All regions with Mediterranean climates have relatively mild winters, but summer temperatures are variable depending on the region. For instance, Athens, Greece experiences rather high temperatures in the summer (48.0 °C has been measured in nearby Eleusina), whereas San Francisco has cool, mild summers due to the upwelling of cold subsurface waters along the coast. Because all regions with a Mediterranean climate are near large bodies of water, temperatures are generally moderate with a comparatively small range of temperatures between the winter low and summer high (although the daily range of temperature during the summer is large due to dry and clear conditions, except along the immediate coasts). Temperatures during winter only occasionally reach freezing and snow occurs only rarely at sea level, but often in surrounding mountains due to wet conditions. In the summer, the temperatures range from mild to very warm, depending on distance from the open ocean, elevation, and latitude. Even in the warmest locations with a Mediterranean-type climate, however, temperatures usually don't reach the highest readings found in adjacent desert regions due to cooling from water bodies, although strong winds from inland desert regions can sometimes boost summer temperatures, quickly resulting in a much-increased forest fire risk.
Inland locations sheltered from or distant from sea breezes can experience severe heat during the summer. Locations in the Northern half of the Sacramento Valley of Northern California, for example, are subject to summer temperatures characteristic of hot desert at times because of high temperture and very low humidity(often around 40°C/104F), although winters are very rainy and foggy enough to allow lushes vegetation than is typical in deserts but the vegetation because a fire risk at times because of dry summers. The central valley of California is not always very hot because of some ocean fluence known as the "delta breeze" which cools temperture during warm summer days. At times the "delta breeze" is strong enough to bring some coastal fog to the valley which brings cooler weather and higher humidity. Unlike the coastal climates that are designated Csb in the Köppen climate classification—characteristic of places with cooler summers—the hotter, typically inland areas are classified as Csa, which indicates a hot summer. Porto, Portugal, experiences the typical Mediterranean pattern of cool, rainy winters and dry summers, but has relatively mild average summer temperatures.
On another note, locations that are slightly higher latitude or elevation and are cut off from milder ocean winds may have somewhat colder winters and more distinct seasons with occasional snow. This "temperate Mediterranean" climate is most noticeable in the Rogue and Umpqua Basins of southwestern Oregon, central Spain, southeastern France away from the immediate coastline, northern Italy, and northern Greece. In these areas some plants (such as citrus) that are commonly associated with milder Mediterranean climates will freeze to death in a severe winter and are thus not part of the regular landscape.
(MY PART ENDS HERE)
Areas of high altitude adjacent to locations with Mediterranean climates, such as the "Mesetas" or plateaus of central Spain, may have the cold winters that are characteristic of a continental climate (see Continental Mediterranean climate); under Köppen's scheme such places might earn the designation Dsa (at lower latitudes above Csa), Dsb (either at high elevations in the lower latitudes or at lower elevations in the mid-latitudes above Csb) or even Dsc (just below the tree line). An example of a very humid Mediterranean Snow climate Dfsc is the highest summit on Orjen, Zubacki kabao in the subadriatic Dinaric Alps in Montenegro."
There's also a big discussion on the discussion page about whether the PNW counts as Mediterranean. Just go to Wikipedia.org and type in "Mediterranean climate" to read it and get the top page links to the discussion.
The above followup was added by Eric, Eugene on March 03, 2009 at 9:45 pm PST.
I started reading the discussion but it got too frustrating. Too many posters insisting that the PNW is lush and green year-round, constantly rainy, and that mediterranean type climates are always hot, sunny and dry. In other words, people who have no clue what they're talking about.
Your addition to the article sounds good. I would also add to that "rainshadow zones" such as those in the Olympic rainshadow, which experience pronounced summer drought and rainfall amounts about typical of most med climate areas, yet are more susceptible to cold outbreaks in the winter despite overall mildness (like Victoria, SSI, Sequim WA, or other locations in that general area)
The above followup was added by Dave, Vancouver Island, z8b on March 03, 2009 at 10:47 pm PST.
Here's my slice of the Mediterranean
I took this picture last week......
The above followup was added by Matt-Eureka CA on March 04, 2009 at 10:32 am PST.
The Angels trumpet got nailed
I planted it too late in the season and I don't think it had the hardiness development quite yet......others around town look fine.
The above followup was added by Matt-Eureka CA on March 04, 2009 at 10:34 am PST.
This echium sprouted from last years plant, and there's actually 4 other little ones coming from this one.
The above followup was added by Matt-Eureka CA on March 04, 2009 at 10:35 am PST.
Pheonix and trachy
Planted this little trachy last thanksgiving.....it was only a one gallon palm.
The above followup was added by Matt-Eureka CA on March 04, 2009 at 10:36 am PST.
These three self seeded in this location....they are actually much taller now compared to last week.
The above followup was added by Matt-Eureka CA on March 04, 2009 at 10:38 am PST.
Big Phoenix and Cordy
This place is just down the street from me...the cordy is sprouting its seeds.
The above followup was added by Matt-Eureka CA on March 04, 2009 at 10:39 am PST.
Austin Texas "looks" kind of Med.
To me south central TX "Hill Country"--San Antonio, Austin kind of look Mediterranean. I know there not at all but the scrub oak and Cedar from a distance on a dry day almost has a look.
The above followup was added by BillMS7B on March 04, 2009 at 8:03 pm PST.
Austin's subtropical savanna
...or is it just warm temperate?
One thing about Northwest places that look kind of Mediterranean is that we also have the seasonal rain patterns to go along. True, most places west of the Cascades and north of Roseburg are too wet to get the scrubby woodland, but those few spots that do get enough sunshine and summer drought have the classic Mediterranean look AND the wet winters and sunny summers to go along. Again, the Gulf Islands and eastern Columbia Gorge are the two most obvious examples of such an enclave outside the proper Med. zone, with the central Willamette Valley perhaps a distant third were it not for all the agricultural alteration of the landscape.
That doesn't mean, however, that the same vegetative pattern cannot exist in subhumid climates that get the bulk of their rain outside the winter season.
The above followup was added by Eric, Eugene on March 05, 2009 at 3:07 am PST.
One more comment
The Koppen system puts the Mediterranean climates into the Cs category, not the B category. B climates are arid or semiarid, yet many places in California that are marked as Cs have less than 50cm of rain per year. Is there some special exception built into the classification system that allows overall semiarid climates to be classified as C or D if their moisture is concentrated in the winter?
The above followup was added by Eric, Eugene on March 05, 2009 at 3:16 am PST.
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