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Yes, but a 10 minute drive inland and you've got yourself average summer temps in the 90's and over 3000 hours annual sunshine. And a crap load of palm trees aswell. That to me spells "Mediterranean" more than any cold and gloomy climate with short lukewarm summers ever will just because some of those climates have summer min and winter max rainfall pattern.
In any case, even the extreme coastal spots in Southern California make a meal of anywhere in the Pacific Northwest, particularly in winter. I'd regard palm trees, 19C winters and sunshine as more evocative of the Mediterranean than 5C drizzly wet gloomy muck.
Going by this rule, the border between Mediterranean and Oceanic in the US is a bit south of Eugene, OR. Going east of the Cascades, shouldn't count, as the mountains are creating another climate, not a micro climate.
Eugene and northward gets so much precipitation annually and the dry season is short enough that the vegetation has little in common with a Mediterrean climate.
Further ammunition to my case. To regard a temperate climate (group C, and summer letter b) with a true dry season as oceanic is stupid. Whether you decide to label it "Mediterranean" is something else, but a dry-summer temperate classification is obviously warranted. The very definition of this climate, and the definition of Mediterranean climate, is a climate with temperate or subtropical temperatures that has a true dry season in the summer months. I don't know why it is so hard for so many people to accept that these West Coast climates do have a summer dry season and thus do have a Mediterranean climate. It is merely baseless emotionalism, to say "oh, that climate can't be Mediterranean, it doesn't fit my stereotype", and it is equally baseless to say that about subtropical, continental, subarctic, or any other kind of climate. It would be like me saying that any location that can get above 40F in the winter isn't a real continental climate, and try to shoehorn "subtropical climate" to fit the tossed-aside portions of the continental zone when they are obviously not subtropical. It's the same thing as tossing out a good chunk of the Mediterranean zones and trying to shoehorn oceanic climate to fit them when obviously they are not oceanic.
Kaul's position notwithstanding of course. He's using the oceanic/maritime label to apply to any place with a maritime influence, i.e. tighter annual range, lower daily range, less variability. This is regardless of temperature or temperateness, which is a completely different animal than the conventional Cfb/Cfc types being under that umbrella. In that respect Seattle and Portland are maritime, but so is Ust'Kamchatsk, Russia, Nome, Alaska, Nain, Labrador, and Boston, Massachusetts. As far as this climate classification goes Kaul's position is irrelevant.
This is far more interesting than the old warm vs cold debate
No doubt you have unarguable point: If one uses the original Koppen definition of what was classified as Csb (C=Temperate, s = dry summer, b= cool summer )…Seattle and Portland fit into this climate classification. Relative to their annual rhythm of rainfall, there is no doubt that these cities have a distinct dry season, fleeting as it may be. I also agree that there is an “emotionalism” to climate classification (and even climate data) that often smothers the facts and true character of any climate. As I have mentioned several times, one of my biggest sources of general amazement is that this “emotionalism” is often used to define a climate based on extremes or sensible weather elements that occur 1% of the year (and using this 1% to define the other 99% –lol).
Having said that, when you look at climate classifications (or the grouping of any scientific data) it seems only logical to group things that share similar properties. In climate classification there has always been a motivation to group climates using genetics (i.e causative factors, like air masses, wind zones…etc) and less into just using a certain threshold of temp or rainfall. It that regard, I disagree this you (and less you, than the use of the Koppen system which you seem to base much of this on). The wording used in the grouping is really the real problem I think.
IMO, it seems stupid to group locations like Seattle or Portland, places where stormy weather, fast changing pressure graindents, unstable weather, frequent cloudy skies, many rain days, frequently cool/chilly weather, moderate to high annual rainfall totals, and a flow of high dew point/humid air flow occurs much of the year…into the same group as say Los Angeles or Greece, where much of the year the weather is dominated by deep high pressure (both at the surface and aloft), stable weather conditions, a dearth of weather disturbances, blazing sunny skies, warm to hot temps, desert like humilities/dew points (and much different rates of evaporation), and a marked nocturnal cooling (the opposite of oceanic climates).
This is why I think the Koppen system and classifications are not nearly as accurate as the more modern Terwartha classifications. Koppen attempted to put the whole North American West Coast from northern Mexico to almost Alaska into the same Cs zone (though he did use a third letter to make the distinction of cool vs warm summers). Trewartha effectively split this massive zone based to a great deal on the genetics of climate. It seems to make far more sense:
This is far more interesting than the old warm vs cold debate
No doubt you have unarguable point: If one uses the original Koppen definition of what was classified as Csb (C=Temperate, s = dry summer, b= cool summer )…Seattle and Portland fit into this climate classification. Relative to their annual rhythm of rainfall, there is no doubt that these cities have a distinct dry season, fleeting as it may be. I also agree that there is an “emotionalism” to climate classification (and even climate data) that often smothers the facts and true character of any climate. As I have mentioned several times, one of my biggest sources of general amazement is that this “emotionalism” is often used to define a climate based on extremes or sensible weather elements that occur 1% of the year (and using this 1% to define the other 99% –lol).
Having said that, when you look at climate classifications (or the grouping of any scientific data) it seems only logical to group things that share similar properties. In climate classification there has always been a motivation to group climates using genetics (i.e causative factors, like air masses, wind zones…etc) and less into just using a certain threshold of temp or rainfall. It that regard, I disagree this you (and less you, than the use of the Koppen system which you seem to base much of this on). The wording used in the grouping is really the real problem I think.
IMO, it seems stupid to group locations like Seattle or Portland, places where stormy weather, fast changing pressure graindents, unstable weather, frequent cloudy skies, many rain days, frequently cool/chilly weather, moderate to high annual rainfall totals, and a flow of high dew point/humid air flow occurs much of the year…into the same group as say Los Angeles or Greece, where much of the year the weather is dominated by deep high pressure (both at the surface and aloft), stable weather conditions, a dearth of weather disturbances, blazing sunny skies, warm to hot temps, desert like humilities/dew points (and much different rates of evaporation), and a marked nocturnal cooling (the opposite of oceanic climates).
This is why I think the Koppen system and classifications are not nearly as accurate as the more modern Terwartha classifications. Koppen attempted to put the whole North American West Coast from northern Mexico to almost Alaska into the same Cs zone (though he did use a third letter to make the distinction of cool vs warm summers). Trewartha effectively split this massive zone based to a great deal on the genetics of climate. It seems to make far more sense:
.
I agree with you, but your statement that the dry season of the PNW is only a short fleeting 1% is an exaggeration. In general climate patterns, the PNW fits closely with its west coast counterpart in Europe. But for summers, at least 3 months, the Pacific Northwest feels nothing like North Western Europe. Its unusual summer patterns are too large to be ignorable. In many ways, the Pacific Northwest is the biggest outlier among "oceanic" climates in the world, and that's why we're having this argument. Southern England in the summer feels like a cooler version of New England; dew points are lower but relative humidity is not all that low. Convective is possible, it's cloudier than the Northeast but the cloud patterns are similar. The Pacific Northwest feels more like coastal California: mostly cloudy in the morning, clouds burn off to create mostly clear skies. Some drizzle but not convective and very little rainfall. Sunshine percentages relatively high. The summer weather patterns of NW Europe felt less "foreign" to me than the Pacific Northwest. As Trewatha listed the Pacific Coast as an "unusual climate". Nowhere else on earth does the summer high pressure dome extend so far poleward on the west coast. It's telling that Northwestern Europe's vegetation is more similar to the US Northeast than to the Pacific Northwest. And Coastal California has unusually cool summer for a Mediterranean climate.
In some ways, California gets similar weather patterns to the Pacific Northwest: it just gets much more of the dry season type weather and much less of the wet season type weather. (I'm referring mostly California north of 35°N, Southern California is borderline semi-arid). Coastal California has a similar or small diurnal range, especially in summer (compare Oakland to Seattle). But there's a sharp transition around 40° or so, matching your map.
I would place the Pacific Northwest in the Oceanic climate type with a big asterisk.
I agree with you, but your statement that the dry season of the PNW is only a short fleeting 1% is an exaggeration. In general climate patterns, the PNW fits closely with its west coast counterpart in Europe. But for summers, at least 3 months, the Pacific Northwest feels nothing like North Western Europe. Its unusual summer patterns are too large to be ignorable. In many ways, the Pacific Northwest is the biggest outlier among "oceanic" climates in the world, and that's why we're having this argument. Southern England in the summer feels like a cooler version of New England; dew points are lower but relative humidity is not all that low. Convective is possible, it's cloudier than the Northeast but the cloud patterns are similar. The Pacific Northwest feels more like coastal California: mostly cloudy in the morning, clouds burn off to create mostly clear skies. Some drizzle but not convective and very little rainfall. Sunshine percentages relatively high. The summer weather patterns of NW Europe felt less "foreign" to me than the Pacific Northwest. As Trewatha listed the Pacific Coast as an "unusual climate". Nowhere else on earth does the summer high pressure dome extend so far poleward on the west coast. It's telling that Northwestern Europe's vegetation is more similar to the US Northeast than to the Pacific Northwest. And Coastal California has unusually cool summer for a Mediterranean climate.
In some ways, California gets similar weather patterns to the Pacific Northwest: it just gets much more of the dry season type weather and much less of the wet season type weather. (I'm referring mostly California north of 35°N, Southern California is borderline semi-arid). Coastal California has a similar or small diurnal range, especially in summer (compare Oakland to Seattle). But there's a sharp transition around 40° or so, matching your map.
I would place the Pacific Northwest in the Oceanic climate type with a big asterisk.
To be fair there is a considerable differences in degree in dryness. Most places in the PNW average at least .5 inches of rain even in the driest month, and nearly 1 inch per month if you look at summers as a whole.
Places in the Bay Area may have more than one month where precipitation is less than 0.1 inches.
I know we are talking about very small numbers here but still, NoCal gets 5 to 10 times less precipitation during summer months than PNW.
I agree with you, but your statement that the dry season of the PNW is only a short fleeting 1% is an exaggeration. In general climate patterns, the PNW fits closely with its west coast counterpart in Europe. But for summers, at least 3 months, the Pacific Northwest feels nothing like North Western Europe. Its unusual summer patterns are too large to be ignorable. In many ways, the Pacific Northwest is the biggest outlier among "oceanic" climates in the world, and that's why we're having this argument. Southern England in the summer feels like a cooler version of New England; dew points are lower but relative humidity is not all that low. Convective is possible, it's cloudier than the Northeast but the cloud patterns are similar. The Pacific Northwest feels more like coastal California: mostly cloudy in the morning, clouds burn off to create mostly clear skies. Some drizzle but not convective and very little rainfall. Sunshine percentages relatively high. The summer weather patterns of NW Europe felt less "foreign" to me than the Pacific Northwest. As Trewatha listed the Pacific Coast as an "unusual climate". Nowhere else on earth does the summer high pressure dome extend so far poleward on the west coast. It's telling that Northwestern Europe's vegetation is more similar to the US Northeast than to the Pacific Northwest. And Coastal California has unusually cool summer for a Mediterranean climate.
In some ways, California gets similar weather patterns to the Pacific Northwest: it just gets much more of the dry season type weather and much less of the wet season type weather. (I'm referring mostly California north of 35°N, Southern California is borderline semi-arid). Coastal California has a similar or small diurnal range, especially in summer (compare Oakland to Seattle). But there's a sharp transition around 40° or so, matching your map.
I would place the Pacific Northwest in the Oceanic climate type with a big asterisk.
My point about the shortness of the dry season in the Do climate of the PNW is when it is compared to the Cs/Mediterranean climate of California. As MrMarbles quite correctly points out – even the two driest months (July/August) at stations like Portland/Seattle, they still have more than half an inch of rainfall, and the others dry months of June/August/Sept receive 1.50 inches of rainfall (roughly). Seattle averages 4.59 inches of rainfall in the 4 warmest months (June – Sept). Compare that with stations like San Diego, Los Angeles, Santa Barbara,...etc which average about 0.31 to 0.49 inches of rainfall from June through Sept (and 3/4 rainless months are not uncommon). It seems unfair to group these climates together based on their amount of summer precip. Seattle or Portland do have dry summers - but they hardly have the true genetic Mediterranean climate controls with close to zero summer precip, frequent cloudless skies, and desert like humidty values that are often the rule in the Mediterranean summer.
In terms of the Pacific Northwest feeling nothing like North Western Europe, I assume you mean in terms of sensible weather. I would disagree with on that one. Having spent time in the Do sector in NW Europe (London, Paris, Belgium...etc) as well as having been in the Do PNW sector (Seattle)...the sensible weather elements were quite similar to me. Using Paris and Seattle that I spent the most time in – Paris might receive far less precip than Seattle in the summer season, but the overall coolness of the summer afternoons, the feel of the maritime air masses (ever present), the passing puffy clouds, and the weak solar angle felt very similar in both cities. Of course nether Paris or Seattle felt anything remotely like the sensible weather elements of a Mediterranean summer (Los Angeles, Athens, and Naples I’ve been in during summer). The hot temps, intense sun, dry desert like air masses, strong nocturnal cooling, ...etc in Los Angeles for example feels nothing like a summer in Seattle or Paris. To someone who has experienced a summer in all of these climates there could be no mistaking the far different feel in the summer months.
As far as Southern England in the summer “feeling” like a cooler version of New England, again I would have to disagree. I have not spent a great deal of time above NYC/coastal CT on the East Coast nor in England, but a few summer visits and more importantly being familiar with the synoptic elements/daily weather map , I think an average summer would feel different in these two locations; Southern England and New England have quite different source regions for their summer air masses: Cool and stable mP air masses (Maritime Polar) dominate the flow over England and far NW Europe in summer...while a mix of driermodified cPk (Conteintal Polar ) and wet/tropical mTu (Maritime Tropical) are the source regions for summer air masses in New England (even northern New England at times). Dew points in summer in New England reach levels that England will rarely see. While far northern coastal New England (perhaps parts of coastal Maine) might have similar mean temps in the summer months as far southern England... the summer air masses over these regions averaged out are different in summer. Of course in winter the difference is even more prononced, as England sees far less dry continental polar air than New England...and far more moist mild maritime polar influnces the English winter.
Last edited by wavehunter007; 04-11-2012 at 03:16 PM..
My point about the shortness of the dry season in the Do climate of the PNW is when it is compared to the Cs/Mediterranean climate of California. As MrMarbles quite correctly points out – even the two driest months (July/August) at stations like Portland/Seattle, they still have more than half an inch of rainfall, and the others dry months of June/August/Sept receive 1.50 inches of rainfall (roughly). Seattle averages 4.59 inches of rainfall in the 4 warmest months (June – Sept). Compare that with stations like San Diego, Los Angeles, Santa Barbara,...etc which average about 0.31 to 0.49 inches of rainfall from June through Sept (and 3/4 rainless months are not uncommon). It seems unfair to group these climates together based on their amount of summer precip. Seattle or Portland do have dry summers - but they hardly have the true genetic Mediterranean climate controls with close to zero summer precip, frequent cloudless skies, and desert like humidty values that are often the rule in the Mediterranean summer.
In terms of the Pacific Northwest feeling nothing like North Western Europe, I assume you mean in terms of sensible weather. I would disagree with on that one. Having spent time in the Do sector in NW Europe (London, Paris, Belgium...etc) as well as having been in the Do PNW sector (Seattle)...the sensible weather elements were quite similar to me. Using Paris and Seattle that I spent the most time in – Paris might receive far less precip than Seattle in the summer season, but the overall coolness of the summer afternoons, the feel of the maritime air masses (ever present), the passing puffy clouds, and the weak solar angle felt very similar in both cities. Of course nether Paris or Seattle felt anything remotely like the sensible weather elements of a Mediterranean summer (Los Angeles, Athens, and Naples I’ve been in during summer). The hot temps, intense sun, dry desert like air masses, strong nocturnal cooling, ...etc in Los Angeles for example feels nothing like a summer in Seattle or Paris. To someone who has experienced a summer in all of these climates there could be no mistaking the far different feel in the summer months.
As far as Southern England in the summer “feeling” like a cooler version of New England, again I would have to disagree. I have not spent a great deal of time above NYC/coastal CT on the East Coast nor in England, but a few summer visits and more importantly being familiar with the synoptic elements/daily weather map , I think an average summer would feel different in these two locations; Southern England and New England have quite different source regions for their summer air masses: Cool and stable mP air masses (Maritime Polar) dominate the flow over England and far NW Europe in summer...while a mix of driermodified cPk (Conteintal Polar ) and wet/tropical mTu (Maritime Tropical) are the source regions for summer air masses in New England (even northern New England at times). Dew points in summer in New England reach levels that England will rarely see. While far northern coastal New England (perhaps parts of coastal Maine) might have similar mean temps in the summer months as far southern England... the summer air masses over these regions averaged out are different in summer. Of course in winter the difference is even more prononced, as England sees far less dry continental polar air than New England...and far more moist mild maritime polar influnces the English winter.
I could have said an English summer feels similar to a Long Island summer but cooler (when I meant New England I was including coastal CT). Of course the dew points are much lower in the UK than in the Northeast, but so are the temperatures. Relative humidity is still high. Summer dew points in London average around 55°F; Seattle low 50s; interior New England low 60s. So yea, the UK is a bit closer to the Pacific Northwest but still noticeably different and the British cloud patterns seem different from the Pacific Northwest. I've seen thunderstorms in the UK in the summer, this wouldn't happen in the Pacific Northwest. The Pacific Northwest is dominated by high pressure in the summer; northwest Europe is not. I've spent months in both the Pacific Northwest and the UK.
Also, we're comparing the Pacific Northwest to coastal California not hot Mediterranean climates (as in Csb climates not Csa ones). Coastal California has similar summer temperatures to the Pacific Northwest and similar nighttime cooling patterns (by a little after sunset it cools down quickly to the daily low). But in any case, the diurnal range of LA is lower than Seattle in July.
I do agree the Pacific Northwest has more in common with Northwestern Europe and other oceanic climates than anything else. However, in the summer, its weather patterns are unusual from its dryness and high pressure. Someone going from the Pacific Northwest down to say, San Francisco would find the summer weather patterns very similar, except for drizzle being less frequent.
This is another issue that sheads some light on how just using summer precip can me misleading. A Cs climate like LA might get the same about a precip in a given month as Seattle - but due to several reasons, water loss is far greater at the surface in LA than it ever would be in Seattle.
A better comparison would be two Csb climates with similar precipitation; San Rafael to [url=http://en.wikipedia.org/wiki/Seattle#Climate]Seattle. Coastal California can get redwood forest; coastal PNW gets temperate rain forests.
Trees a bit taller and more lush for Seattle, but many plant types in common (large conifers but more Mediterranean shrub and short trees for the California views)
In terms of the Pacific Northwest feeling nothing like North Western Europe, I assume you mean in terms of sensible weather. I would disagree with on that one. Having spent time in the Do sector in NW Europe (London, Paris, Belgium...etc) as well as having been in the Do PNW sector (Seattle)...the sensible weather elements were quite similar to me. Using Paris and Seattle that I spent the most time in – Paris might receive far less precip than Seattle in the summer season, but the overall coolness of the summer afternoons, the feel of the maritime air masses (ever present), the passing puffy clouds, and the weak solar angle felt very similar in both cities. Of course nether Paris or Seattle felt anything remotely like the sensible weather elements of a Mediterranean summer (Los Angeles, Athens, and Naples I’ve been in during summer).
The only difference is that the summers you experienced were in the hot summer Mediterranean climates, not the warm summer variety. A more valid comparison would be San Francisco or the immediate L.A. coastline. Just because a place has a summer letter of "b" instead of "a" does not and should not disqualify it from being Mediterranean, much less cause for being classified as oceanic. Are the temperatures similar? Sure. But this isn't about temperatures. Unless anywhere in Northwest Europe receives sparse precipitation and endless sunshine in summertime like Seattle and Portland do, I'd advise you to stop pushing this absurd notion that Seattle/Portland are similar to Northwestern Europe. Do Mediterranean climates have weather similar to oceanic climates in winter or in most of the year? Sure, but that's not the difference between the two. Even Csa climates receive weather like many oceanic climates in wintertime. The difference is that Mediterranean climates have a dry and usually sunny season in the summer. The very nature of Mediterranean climates is to have oceanic weather interrupted by a true dry season in summer.
Nei put it best:
Quote:
Originally Posted by nei
I could have said an English summer feels similar to a Long Island summer but cooler (when I meant New England I was including coastal CT). Of course the dew points are much lower in the UK than in the Northeast, but so are the temperatures. Relative humidity is still high. Summer dew points in London average around 55°F; Seattle low 50s; interior New England low 60s. So yea, the UK is a bit closer to the Pacific Northwest but still noticeably different and the British cloud patterns seem different from the Pacific Northwest. I've seen thunderstorms in the UK in the summer, this wouldn't happen in the Pacific Northwest. The Pacific Northwest is dominated by high pressure in the summer; northwest Europe is not. I've spent months in both the Pacific Northwest and the UK.
Also, we're comparing the Pacific Northwest to coastal California not hot Mediterranean climates (as in Csb climates not Csa ones). Coastal California has similar summer temperatures to the Pacific Northwest and similar nighttime cooling patterns (by a little after sunset it cools down quickly to the daily low). But in any case, the diurnal range of LA is lower than Seattle in July.
I do agree the Pacific Northwest has more in common with Northwestern Europe and other oceanic climates than anything else. However, in the summer, its weather patterns are unusual from its dryness and high pressure. Someone going from the Pacific Northwest down to say, San Francisco would find the summer weather patterns very similar, except for drizzle being less frequent.
-I suggest that Patricius Maximus not let his obsession with precipitation rhythm to overlook the other real weather elements that define a climate, specifically an oceanic climate. The Pacific coastline of the North American continent is inherently different from Northwestern Europe in its ability to produce consistent precipitation throughout the year. Precisely, there is not a single oceanic climate in North America that will give similar precipitation rhythms to Northwestern Europe. Oceanic climates can have variety as well, and the European, or American variety could be said to be a subset of the larger oceanic domain. Using the sensible elements that wavehunter talked about, the maritime climate of Northwestern Europe is indeed very similar to the Pacific Northwest.
- To corroborate my stance on this, Ketchikan, Alaska is a downright classic example of an oceanic climate. Despite of its "oceanic" label, its summers are drastically drier in relative to the rest of the year. The precipitation rhythm of Ketchikan isn't really that different from Seattle or SOCAL. The precipitation ratio of the wettest to driest month in Ketchikan is comparable that of coastal PNW. Ketchikan, Alaska - Wikipedia, the free encyclopedia
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