Jump to content
Sign in to follow this  
bubba

Zone 11

Recommended Posts

bubba

There is alot of discussion on this Board about Zone 11. The definition of Zone 11 seems nebulous at best when it discusses "an average minimum temperature of 40 degrees F."What does that mean?The last time I remember it dropping below 40 degrees F. in this area was 1989.(Palm Beach)At anyrate, the National Arbor Day Foundation completed an extensive revision of this map ,which is available on the Wikipedia Hardiness Zone article. This article also lists the Hardiness Zones for numerous American cities.In California,San Diego,Los Angeles and San Francisco are identified as Zone 10. The only American cities designated Zone 11 are Miami,Florida and Honolulu,Hawaii.As it relates to California, Desmond Muirhead in his book"Palms" states that their are really no frost-free areas in California.He details the cyclical bad frosts that hit in 1913,1922,1937 and 1949.The book was written in 1961 so you can fill in the rest of the blanks.He also indicates that a freezing temperature was recorded on the Catalina docks and states that even the banana belts above La Jolla and Golita are not immune.Although "urban myths"may detail certain hot spots that defy this analysis,and may allow for a coconut palm, I do not believe these areas are large enough to qualify for a Zone 11 designation.

Share this post


Link to post
Share on other sites
alex_7b

An occasional frost will not kill a coconut. Even if it occurs every 10 years, a coconut will gain alot of mass in the intervening 9 years. What will kill them of faster, is the low average temperature of the air and the soil.

Although they're not as sensitive as Latania, even a few cool weeks with soil temps in the 60's will cause problems.

Share this post


Link to post
Share on other sites
spockvr6

(bubba @ Oct. 11 2007,15:56)

QUOTE
The last time I remember it dropping below 40 degrees F. in this area was 1989.(Palm Beach).

Bubba-

I hate to accuse you are having a short memory.....but the WPB AP logged 36F just last February!  And, there were probably half a dozen nights in 2006 where the temp was below 40F.

Share this post


Link to post
Share on other sites
spockvr6
The definition of Zone 11 seems nebulous at best when it discusses "an average minimum temperature of 40 degrees F."What does that mean?

It means that, for the time period that the data represents (and this time period varies with each map that out there), if the lowest temperature of each winter were averaged over that designated period, the value would be 40F or greater to get the Zone 11 designation.  It doesnt mean that there werent certain events below 40F, only that the average of the extremes of each year were above 40F.

In the case of the 2006 Arbor Day map, I believe they used the last 15 years worth of data.  So, its probably based on 1990-2005.   So, its easy to see how some zones got bumped up without all those nasty 1980's winters averaged in.  Whether or not the 1980's were a recent anomaly or a cyclical trend....who knows!  I guess we shall see over time.

Share this post


Link to post
Share on other sites
NBTX11

(spockvr6 @ Oct. 11 2007,22:06)

QUOTE

(bubba @ Oct. 11 2007,15:56)

QUOTE
The last time I remember it dropping below 40 degrees F. in this area was 1989.(Palm Beach).

Bubba-

I hate to accuse you are having a short memory.....but the WPB AP logged 36F just last February!  And, there were probably half a dozen nights in 2006 where the temp was below 40F.

Wouldn't the wpb airport be 5 degrees or so cooler than PB itself, so I can see how PB may have not dropped below 40.

Share this post


Link to post
Share on other sites
NBTX11

(spockvr6 @ Oct. 11 2007,22:08)

QUOTE
The definition of Zone 11 seems nebulous at best when it discusses "an average minimum temperature of 40 degrees F."What does that mean?

It means that, for the time period that the data represents (and this time period varies with each map that out there), if the lowest temperature of each winter were averaged over that designated period, the value would be 40F or greater to get the Zone 11 designation.  It doesnt mean that there werent certain events below 40F, only that the average of the extremes of each year were above 40F.

In the case of the 2006 Arbor Day map, I believe they used the last 15 years worth of data.  So, its probably based on 1990-2005.   So, its easy to see how some zones got bumped up without all those nasty 1980's winters averaged in.  Whether or not the 1980's were a recent anomaly or a cyclical trend....who knows!  I guess we shall see over time.

Larry, if you look at every zone map that has ever been created, even going back to the map made in the 60s, the 1990 map is the one that sticks out like a sore thumb.  Every other map has been in line more with the 2006 map and the 1990 map is an anomoly.  Some people say the 1989 freeze was a 50-100 year freeze...we probably won't see that again in our lifetimes.

Share this post


Link to post
Share on other sites
happ

Bottom line is frost  :o If you do not experience temperatures below 32F/0c then your area is in a 365-day growing season.  San Francisco is at latitude 37.775N [same as Virginia/Kansas/Colorado] but is frost-free [50 yr event].

Technology & weather nerd/squad reports to NWS has allowed better identification of climate ["1961" a little dated  :laugh:

So what happens is that Californios introduce palms/tropicals incompatible with growth.  Watched a once healthy bethel nut not produce a leaf in a year  :o nothing dies until you end it  :laugh:

to be honest I seriously injured catechu by way of a disastrous/shameful  transplant.  Tropical palms don't grow well in California [ex freakish micro-climates/ie. Newport Beach.  It is too cool for too long to allow anything beyond 6-months of growth.  Just when the beauties fully leaf out the cold season is upon us  :(  probably half the heat of SoTexas/Florida.

A cruel joke on anxious Cali growers who wait & wait. On the other hand, Texas/Florida are prone to devastating freezes far more often than in California.

We do our best with what we got, right  ???

Share this post


Link to post
Share on other sites
NBTX11

(happ @ Oct. 11 2007,22:29)

QUOTE
Bottom line is frost  :o If you do not experience temperatures below 32F/0c then your area is in a 365-day growing season.  San Francisco is at latitude 37.775N [same as Virginia/Kansas/Colorado] but is frost-free [50 yr event].

Technology & weather nerd/squad reports to NWS has allowed better identification of climate ["1961" a little dated  :laugh:

So what happens is that Californios introduce palms/tropicals incompatible with growth.  Watched a once healthy bethel nut not produce a leaf in a year  :o nothing dies until you end it  :laugh:

to be honest I seriously injured catechu by way of a disastrous/shameful  transplant.  Tropical palms don't grow well in California [ex freakish micro-climates/ie. Newport Beach.  It is too cool for too long to allow anything beyond 6-months of growth.  Just when the beauties fully leaf out the cold season is upon us  :(  probably half the heat of SoTexas/Florida.

A cruel joke on anxious Cali growers who wait & wait. On the other hand, Texas/Florida are prone to devastating freezes far more often than in California.

We do our best with what we got, right  ???

Exactly why you see a handful of Cocos Nucifera in deep S. TX (RGV)  along with quite a few royals, etc.  I don't think a lot of people would say S. TX has warmer winter lows than LA or SD, but they are much, MUCH hotter year round, and the occasional frost/freeze is usually very brief (unless of course an 80s type freeze hits).

It can be 90F every month of the year in S. TX, it has hit 100F in Feb for the Feb record high in San Antonio for example.

On the other hand, we can count of those stupid cold fronts that blow through a handful of times each winter, ruining otherwise warm winters.

Share this post


Link to post
Share on other sites
mnorell

Remember that the USDA-defined zones are indeed only a mathematical average of one factor in climatology, and that doesn't take into account the accumulated heat of the growing season, the average temp in winter, etc. and their effects on growing plants. Many coastal areas, especially in California or in other areas that have large bodies of water between colder air-sources and themselves, can make much more use of climatological averages than can areas that come under the influence of landmasses periodically hit by waves from the Arctic or Antarctic, such as the "semi-tropical" Gulf South and Atlantic Southeast.

I was born in Southern California, and lived there for decades, for years in the air-drained "banana belts" of Hollywood, and those areas in particular must be a relatively safe zone 11; it was consistently above 40F each year...but of course the constant nighttime chill year-round and the relatively cool days go a long way toward compromising the ability of many lower-elevation tropicals to thrive or even survive. You can go years in coastal SoCal remaining pretty close to climatology, but then you get a 1913, 1937, 1949, 1990, 2007 that knocks you out of the ballpark with some temps in low-lying areas as low as the teens! Also warm-water-bathed places like Miami Beach and the Keys, and I'm sure many areas within sight of the ocean along the lower east coast of Florida also can pretty well go by climo averages until you get a 1989 event.

Here in Natchez, Mississippi I now live in a 9a microclimate with 8b in the surrounding areas, with much variation due to very hilly topography, lake/river influences and cold and warm air-mass influences...and averages are about 43/60 in January where I live; 3-12 degrees colder at night in the outlying suburbs and countryside. That said, I think we may have had our "average" 43/60 one day last winter. Usually it's either about 35/52 or 55/75, with some miserably overcast 40/45 mixed in just to make us dream of spring; and two-thirds of the winters will be on target at 20-25F for a minimum. But it also has hit 5-10F a good ten times at least since the 4F event in 1899. But even so, it's still a zone 9! And many heat-loving tropicals, especially herbaceous plants and root-hardy woody shrubs/vines, grow gloriously here where they sulk in frost-free areas of SoCal. There's where the map and the plant-zone folks fall down making gross generalizations.

Now if the USDA and NOAA would realize that it's ridiculous to base these zones on short-term data, as they did with the 1990 map, and it's sad that it it has become the de facto map published in every book...it would be good for all of us to do our own calculations for as much data as exists and then compare them with these maps. Hopefully the new "official" map (Tony Avent is working on this one, which means that hopefully we will get our beloved a/b zones back!) will be much more accurate.

On that topic, has anybody else noticed that every AHS-published book has a completely wrong climate-zone map, with zones that don't correspond to the text? If I'm remembering correctly, their map is all wrong, showing 10 (incorrectly mapped) zones, and their text refers to something like 15 zones, it's nuts that they've perpetuated this mistake across so many publications, making the books utterly useless to the reader! They show plants that should be listed as zone 8 or 9 as being only applicable to zones 13-15...crazy!

Sorry for the long post!

Share this post


Link to post
Share on other sites
NBTX11

Michael, good post.  We're a lot like you, I'm 9a/b most years averaging between 23-27F in recent

winters, but if you look at the 1990 map we're zone 8b.  The zone 8 winters are few and far between, but they can and do happen.  I think we have had approximately 6 temps on record below 10F, the last one coming in 1989.

Share this post


Link to post
Share on other sites
amazondk

(mnorell @ Oct. 12 2007,00:01)

QUOTE
On that topic, has anybody else noticed that every AHS-published book has a completely wrong climate-zone map, with zones that don't correspond to the text? If I'm remembering correctly, their map is all wrong, showing 10 (incorrectly mapped) zones, and their text refers to something like 15 zones, it's nuts that they've perpetuated this mistake across so many publications, making the books utterly useless to the reader! They show plants that should be listed as zone 8 or 9 as being only applicable to zones 13-15...crazy!

Sorry for the long post!

Michael,

Regarding the 15 zones you mentioned what are the 5 zones higher than 10?  Climate zones aren't really much of an issue where I live except I guess if you wanted to grow cold climate plants.  The all time low here I think was 58 F.  And, that was a very rare event.  As to growing tropical plants how much of an impact is solar radiation on their health?  Here the light intensity is always quite strong even though we never have days much over 12 hours.  I would imagine this would also impact the growth of many tropical plants.

dk

Share this post


Link to post
Share on other sites
mnorell

Don--

I really don't know what the AHS means, if you read their text they say something about the old 10-zone system, and then mention a new system that's been developed specifically for subtropical regions, going to I think 15, and then they never show a map that goes anywhere beyond 10 (at least I don't remember them even showing the standard zone 11 areas such as the Florida Keys or zone 12 areas further south), but the text rates every plant based on something like 15 zones, and I can't imagine what areas they mean...I've looked at this book several times in bookstores trying to figure out if I'm just not seeing something in the text, but it looks like just a tremendous gaff on the part of their editorial staff or that of DK, the actual publisher of these books by AHS.

Likewise I've seen terrible errors in zone maps published elsewhere. In Barnes & Noble's U.S. republication of a Random House Australia title, "Botanica," they use a map that shows zone 8 extending down to the tip of Baja California as well as covering the entire state of Florida through Miami! This also shows a large chunk around Tokyo (not just the urban heat-island) on Honshu as zone 10 and the entire coast of Queensland/NSW (from far north of Brisbane to south of Sydney) as zone 9. In DK's "Flora," it looks like they're using the same map as "Botanica" except that they've corrected the Florida gaff by showing zones 9 and 10. It's just bizarre that these can get past horticultural writers and editors without even a mention or an erratum-insert or corrected, revised edition being issued. It's the primary use for these plant-guides, to look up climate zones and plant hardiness, and they're terribly flawed!

Share this post


Link to post
Share on other sites
bubba

The point of my post is that there cannot be any true Zone 11's in California.Admittedly, the USDA system is fatally flawed.At best it is a plane crash.However, I believe the nuance that the USDA attempts to articulate with this designation is to mathmatically describe what is tropical.Unfortunately, there arbitrary designation does not work.To me the proof is in the palms. The palms do not lie.

As it relates to frost, the National Weather Sevice reports the lowest teperature at the San Francico Airport to be 20 degrees F.and the Los Angeles Airport to be 23 degrees F.I cannot imagine that these cold temperatures did not include frost and one would believe these areas to be warmer than surrounding areas given there close proximity to large bodies of water.

In the Palm Beach area of Florida, geographically we are at the furthest Eastern point of the State.Correspondingly,the Gulf Stream is at it's closest proximity and generally one to three miles maximum off our coast.This large body of moving water remains at a constant 85 to 90 degrees F. year round, including our winter.Our airport is approximately four miles from the ocean and the low temperatures recorded inland bear limited relationship to those experienced on an island surrounded by the Intracoastal Waterway and the nearby Gulfstream.

That, however, is not the point. In order to qualify for inclusion in a Zone,it is my contention that it must be an area large enough to show up on a map.The smallest area to fit this designation would be an area of atleast ten miles.While there may be microclimates in Califonia that fulfill this designation from a temperature point of view,(1000 feet on the side of a hill under an escarpment)there is no way that this qualifies for a Zone 11 designation.A zone must be large enough to show up on a map and the Californian microclimates are simply not large enough to entitle them to be referred to as Zone 11 and to do so is inaccurate.

Share this post


Link to post
Share on other sites
happ

Bubba

Not very scientific "contention" [like saying that since my house doesn't have termites, they don't exist  :laugh: bad analogy [since my house has termites  

Micro-climates can be the crucial factor in where palms live or die.  Los Angeles is quite mountainous.  In a low inversion, I can drive less than a mile and experience a 5 degree jump in temperatures  :P The foothills are becoming more crowded w/ houses barely clinging to the cliff.  Can't estimate the actual population but think it is more than Palm Beach metro [ie Malibu to Montebello 20 miles.

Palm Beach/Miami have also experienced all-time minimums in the 20/snow 1977 but that doesn't mean zone 8.  Conceptually, it is common to think tender palms=Florida/Hawaii.  You are right.  But that doesn't exclude Cali gardeners from succeeding; just takes a hell of a lot longer  :( 2007 freeze didn't effect LA as much [36F/2.2c downtown] due to nocturnal down-slope winds.  Lowest minimum in 1990 freeze:  34F/1.1c  

Zone 11 is frost-free/average lowest minimum 40F/4.4c but there are more concerning issues for palm growers in foothill LA : wind/extremely low RH/dewpoints/40's for weeks  :o

Hope this makes sense  ???

Share this post


Link to post
Share on other sites
bubba

Happ, Your analysis is flawed and you apparently missed the entire point.Your "microclimates" are too small to be considered Zones, even under this admittedly incoherent system devised by the USDA.Your sidehill spotty areas that may qualify are too small, will never be capable of showing up on a map and any reference to your inclusion in Zone 11 is one of your own rendering.Similarly, I could proclaim myself Prime Minister of the Universe but I would be making a false statement.

Share this post


Link to post
Share on other sites
NBTX11

(happ @ Oct. 12 2007,10:56)

QUOTE
Palm Beach/Miami have also experienced all-time minimums in the 20/snow 1977 but that doesn't mean zone 8.  

No, not really.  Most weather sites show the all time record low for Miami as about 32F, some say 31F.  Some say that Miami once got down to 29 or 30, but that usually doesn't show up on the weather data sites.

I am sure PB has had a few temps in the upper 20s.

They lower keys have never dropped below 40F.

There are true zone 11's in S. Florida, including the keys and areas along the coast in the greater Miami areas.

As far as snow in 1977, from what I have heard it was more "flakes" that snow, of course I was not there.

Share this post


Link to post
Share on other sites
happ

Jim

You are correct.  Here's an interesting article

http://www.islandnet.com/~see/weather/alma...02/alm02jan.htm

It has also snowed in LA & especially in 1949 [last occurrence 1962

http://www.laalmanac.com/weather/we17.htm

Here's the critical factor for growing palms & how chilly it is currently in the West:

http://www.hpc.ncep.noaa.gov/heat_index_MAX/bchi_day3.html

Bubba, you are incorrigible  :laugh:

Share this post


Link to post
Share on other sites
fastfeat

"Tropical" is not a designation of a certain range of temperatures, it is a geographical description of the area between the Tropics of Cancer and Capricorn. There are indeed many high-elevation areas, some along the Equator, that are snow-bound 365 days of the year!

Share this post


Link to post
Share on other sites
NBTX11

(happ @ Oct. 12 2007,12:35)

QUOTE
Jim

You are correct.  Here's an interesting article

http://www.islandnet.com/~see/weather/alma...02/alm02jan.htm

It has also snowed in LA & especially in 1949 [last occurrence 1962

http://www.laalmanac.com/weather/we17.htm

Here's the critical factor for growing palms & how chilly it is currently in the West:

http://www.hpc.ncep.noaa.gov/heat_index_MAX/bchi_day3.html

Bubba, you are incorrigible  :laugh:

Interesting tidbit, according to the article, Miami Airport never officially recorded snow in 1977 although snow flakes were observed around the city, so Miami "officially" has not seen snow.

Share this post


Link to post
Share on other sites
elHoagie

I think the whole problem is that the USDA presents their zones as a description of what will grow (i.e. "Royal palms are hardy in zone 10 and above").  But, they define their zones based on a single climatic observable.  Since this is probably the climatic observable to correlates best to what plants will grow, it's a reasonable choice.

But, it makes no sense to say "Royal palms cannot grow in my neighborhood, so I am in USDA zone 9 or lower".  It also makes no sense to say "I live in USDA zone 11, so I live in the tropics".  Again, the USDA zones are based on a single climatic observable, they are not based on the total picture of the climate!

The average yearly low for the past 10 years in downtown LA is 39F, for San Diego it's 41F.  So, it's not just small hillsides that are borderline USDA zone 11 in California.  But, the climate here is cold as hell, and it's definitely not tropical....

Share this post


Link to post
Share on other sites
fastfeat

(happ @ Oct. 12 2007,12:35)

QUOTE
Jim

You are correct.  Here's an interesting article

http://www.islandnet.com/~see/weather/alma...02/alm02jan.htm

It has also snowed in LA & especially in 1949 [last occurrence 1962

http://www.laalmanac.com/weather/we17.htm

Here's the critical factor for growing palms & how chilly it is currently in the West:

http://www.hpc.ncep.noaa.gov/heat_index_MAX/bchi_day3.html

Bubba, you are incorrigible  :laugh:

Happ--

Thanks for the links.

Some scanned pics from Jan 2007 Miami Herald, "celebrating" the 30th anniversary of that infamous day.

(Sorry about the format, my scanner only does 8.5X11. I'm sure there's a link to the pages shown here as well...)

Snow01_sm.jpgSnow02_sm.jpgSnow03_sm.jpg

Share this post


Link to post
Share on other sites
happ

If my hyophorbe looks half as good than I am content.  And these photos were taken from a cooler area than the foothills  :P

100_4702.jpg

we decided to try & find a graden we had toured about 5 years ago with the pssc.

after driving up & down every street in point loma/ocean beach we finally found the place:the amazing garden of dennis willoughby!

100_4701.jpg

hyophorbe species.

100_4703.jpg

100_4704.jpg

heres bob!

Share this post


Link to post
Share on other sites
MattyB

Bubba, if some minimum area of 10 miles needs to be fulfilled to be considered a zone then yes, you're right, there's no Zone 11 in California.  Regardless, there are areas that do fulfill the zone 11 rules of staying above 40F.

As it relates to frost, the National Weather Sevice reports the lowest teperature at the San Francico Airport to be 20 degrees F.and the Los Angeles Airport to be 23 degrees F.I cannot imagine that these cold temperatures did not include frost and one would believe these areas to be warmer than surrounding areas given there close proximity to large bodies of water.

Bubba, although you cannont imagine there not being frost, it is a very real possibility that there was not frost, at least for the LA temp.  And the reason is the same reason that these very areas that are near bodies of water might not be warmer on these given cold event nights.  When we get super duper cold, it's ususally from a cold front coming back at us from the high desert areas.  This air is so amazingly dry that even at low 20's we might not be at our dew point yet and therefore no frost will occur.  This also takes the marine influence right out of the picture and as seen this winter, the San Diego Airport can record colder temperatures then other areas that are at a higher elevation.  The cold goes down and offshore.  The ocean is just along for the ride.

I believe the nuance that the USDA attempts to articulate with this designation is to mathmatically describe what is tropical.Unfortunately, there arbitrary designation does not work.To me the proof is in the palms. The palms do not lie.

Bubba, you got it man!  The palms around you are a much more accurate depiction as to what kind of climate (or microclimate) you live in.  This is why Dean has been developing the Palmpedia Survivability Index.  It's a zone system that is built entirely around palm species.  This way you don't have to know what zone you're in to grow stuff, you can just observe what's growing in that neighborhood, refer to the list, and see what other palms will grow there also.  There's a different index for Mediteranean or Subtropical areas due to the climactic discussions we had above.  The Subtropical index needs a lot of work so get in there and start contributing.  Over time, the more people edit, massage, move stuff around, there should be a pretty good list.  Geoff Stein (palmbob) has put in a lot of work adding species to the Mediteranean index.  Check it out.

Share this post


Link to post
Share on other sites
paulgila

happ those pix look familiar--shouldn't i get "photocredit"or something :D

how did this thread get so W  I  D  E all of a sudden?

Share this post


Link to post
Share on other sites
mnorell

Bubba--

I think you're getting too wrapped up in the implications of the zone-number designation system. Jack is 100% right, the USDA zone simply describes one mathematical figure: the average minimum temperature over a given period of time. Not only have they screwed it up by using a 12-year data-period for the 1990 map, but note also that most weather-recording stations are placed outside of cities at rural or semi-rural airport stations. Meanwhile most people live in spots that run 3-10 degrees warmer than the official readings for their cities! The map is drawn based on those weather-station figures and so for most of us the truth is that we're a bit warmer than the actual reports from the weather stations. That's why it's a good idea for all of us to invest $500 in a good weather system (I use a Vantage Pro2 and it is great!) and post the real-time data online through wunderground via their GoogleMap system...it gives a great idea of exactly how we compare on any given winter morning to the "official" reading for where we live.

I can tell you for a fact that Los Angeles has a good long strip of zone 11, along the south-facing foothills of the Santa Monica Mountains, and that's plenty big to show on a map. Don't forget that the geography of the west makes everything a microclimate! People live at the mouths of canyons, on ridges, along river-bottom areas that freeze every year, etc. And in 1990 L.A. downtown (actually now USC campus) registered only 34 but in Los Feliz where I lived in a bit of a cold-trap it was about 26...everything looked as if it had been hit by a blow-torch and there was frost galore! And when I was a kid in San Diego in the '70s, about 5 miles from the ocean living on a suburban mesa, I crunched across frost on the grass many a morning as I set out for school!

A "zone" is just applicable to the place(s) where the numbers are recorded. Nowhere is there a rule stating that it must be a certain number of square miles. If someone would actually map the differences in temperature between Miami Beach and the cold areas of the Redlands and western Dade, or the difference between the St. Pete-Sarasota area and the areas just to the east around I-75, you might just be surprised how variable Florida is, and it doesn't match the USDA 1990 map too closely in that regard! There simply haven't been enough NOAA weather stations to accurately show the temperature differences in the U.S. due to the great variation over very small areas.

The fact is that in the Gulf and Atlantic-influenced areas palms (and many other plants) respond very differently than they do in the chilly-Pacific-dominated areas of coastal California. There should really be two separate maps to split the western and eastern U.S., and perhaps also the areas north and south of Central California, because the USDA designations fall down when trying to apply them to plant-hardiness there.

Somewhere perhaps there is a perfect way to rate plants, but old Mother Nature usually has something up her sleeve to prove any zone-map wrong...so the lesson is not to take it too seriously or you are bound to be disappointed. Use it as a guideline, but grow what you like and if it survives be a happy camper...if not, maybe you want to try again to see if the second specimen likes the climate better!

Share this post


Link to post
Share on other sites
amazondk

(fastfeat @ Oct. 12 2007,13:09)

QUOTE
"Tropical" is not a designation of a certain range of temperatures, it is a geographical description of the area between the Tropics of Cancer and Capricorn. There are indeed many high-elevation areas, some along the Equator, that are snow-bound 365 days of the year!

I would have to agree with you about this.  There are places that I have been to that have snow in the tropics.  It is definately not accurate to equate lattitude with temperature without taking altitude into account.  Anywhere on Earth this is the case.  Once you get above the tree line in the Rockies it is like being in the Arctic in reality.  In the Andes it is amazing how the climate changes in a short distance when one goes up or down the mountains.

dk

Share this post


Link to post
Share on other sites
bgl

Definitely true. And here on the Big Island of Hawaii, we can do something that very few people anywhere in the world can do: leave sealevel, drive for just over two hours and see the temperature drop by about 40 degrees F (at the summit of Mauna Kea, 13,792 ft a.s.l.)

Share this post


Link to post
Share on other sites
happ

(bgl @ Oct. 12 2007,19:15)

QUOTE
Definitely true. And here on the Big Island of Hawaii, we can do something that very few people anywhere in the world can do: leave sealevel, drive for just over two hours and see the temperature drop by about 40 degrees F (at the summit of Mauna Kea, 13,792 ft a.s.l.)

Bo,

Been there/done that in both Hawaii & California.  One can experience a 40 degree change in temperature just driving from Santa Monica to the San Fernando valley in about 15 minutes on a summer afternoon.  What state/region can top that?  :P

BTW, sorry for not crediting you for those inspiring photos, Paul  :D

Share this post


Link to post
Share on other sites
fastfeat
One can experience a 40 degree change in temperature just driving from Santa Monica to the San Fernando valley in about 15 minutes on a summer afternoon.

When is the last time you've been able to make it from the beach to the Valley on the 405 (or Topanga Canyon) on a Summer afternoon in 15 minutes ?? :D

Share this post


Link to post
Share on other sites
bgl

Happ,

OK, I guess you got me there! But based on Don's post I thought we were talking about places in the tropics that experience snow. Even so, I don't know what shortcuts you know of that can get you from Santa Monica to San Fernando Valley in 15 minutes!!?? :P  And on a summer afternoon!! That must have been back in 1957....! :D

Bo-Göran

Share this post


Link to post
Share on other sites
mnorell

You can't get from Santa Monica to Santa Monica in 15 minutes! It's difficult enough trying to find your way out of the cloud-bank!

Share this post


Link to post
Share on other sites
amazondk

Maybe climate zones make more sense than plant hardiness zones.  This map shows the world by climate zones.  

Bo, unfortunately they left Hawaii off.

dk

climate_map.gif

Share this post


Link to post
Share on other sites
alex_7b
But Miami is not the only place where snowfall is major news. On wednesday, the mountaintops near Malibu Beach in California were dusted in white.

This is part of the caption alongside the photograph in the Miami Herald. Anyoneone remember the Malibu snow?

Share this post


Link to post
Share on other sites
ruskinPalms

I think there is probably zone 11 in California that is big enough to be painted on a map. I think the point that happ is trying to make is that even though it is zone 11, it still kinda sucks. Too cool for too long for a lot tropical palm species. Way too many nights in the 40's with days that may not warm up much at all. Throw a winter rainfall pattern on top of that with realatively cool summers compared to the southeast U.S. and then you can start to see the challenge of palm growing even if it is technically zone 11 by the USDA definitions. That being said, zone 10 and 11 areas of california can look every bit as tropical and lush as zone 10 and 11 areas of FL, just with different palm species that like the cool, but not freezing, temperate/med climate.  The whole california frost debate continues I see. Like it has been stated, the freeze last year was too dry for frost to form. That is not to say that there is not frost in california.  I can't even guess how often it happens there in cali but for my own record keeping here, I define a "frost event" as any time there is any kind of frozen water not from precipitation observable on anything in the area be it only a few flakes on the tops of the cars, windshields and house roofs to an all out white washing like what happened here most recently in feb 2006.  For time period oct 2006 through mar 2007, I observed "frost" by my definition 3 times at my house. 2 times were only car tops and roofs, 1 time a few blades of grass had some frost very sporadically. I am pretty sure that areas deep into southeast florida had frost by my definition a few times last year too. I remember folks reporting car top and windshild ice with temps as high as the low 40's F last year. So my point with all the talk about frost is that a zone 11 is not necessarily frost free. Anyone know if there has ever been frost of any kind in Key West? Cuba? Bahamas? Bermuda?  Interestingly, I tried to get people to make their own zone map based upon their best guess, data they can find, and what grows in the area. I couldn't find the thread but here is the last revision of the map I tried to make for the Tampa Bay area. I went through a few revisions and made adjustments based upon peoples' critique from this forum. This map is still open for critique and revision :)

ZoneMapwithLegend-1.jpg

Share this post


Link to post
Share on other sites
fastfeat

Curious about the 9b designation around Zephyrhills. Is there elevation ("banana belt" in CA terms) that keeps it warmer than the surrounding 9a areas?

Share this post


Link to post
Share on other sites
bubba

Happ, I am incorrigble but it takes alot to get you California folks to open up to the rest of the world. It seems you have to throw a little dynamite stick at you to even get your attention.I do stand by my statement that there are no ZONE11 climates in California but definitely admit that Zone 11 microclimates exist in many places.As Desmond Muirhead states in "Palms"(old but not outdated)Old Town San Diego recorded 18 degrees F. and the hillsides of all San Diego registered atleast 30 degrees F. when San Diego is supposedly frost-free.Also "frost" is not the entire issue.I dare say few things were growing in San Fran when the temperature hit 20 degrees F.or LA when it hit 23 degrees F.How can these areas report 365 days a year growing sasons. If they can, I guarantee South Florida can inasmuch as my yard is mowed once a week year-round and our air conditioner runs year-round.Your attempted end run regarding Florida is a simple misdirection technique to allow you not to deal with the California Zone 11 issue.

The 1977 widespread "snow event"was completely blown out of proportion in that the flurries that never hit the ground and occurred in temperatures above freezing.These flurries occurred all the way over to atleast Green Turtle Island in the Abaco chain of the Bahamas, where a friend of mine saw them with his own eyes when the temperature was around 40 degrees F.

Matt, Your points are cogent ,staightforward and appreciated.

Michael, Your thoughts are very well put together and the only disagreement we have regards California and the Zone 11 designation.

Jack,Same straightforward coherency but once againSan Diego's 10 year average is too short for Zone11.

Jim,Thank you for your straightforward imput as usual.

Paul, Show me some love and I will give it back.

Don K, Leave it to the Amazon boys for the winner. The Koeppen's Climate Classification is the closest to rendering a true equilibrium between what the idiotic USDA attempts to artificially calculate whatever and "the truth". The Palms do not lie.

Bo,I guess I got your attention with the National Arbor map, which shows Honolulu and Miami in the same designation.

Bill and Larry,Insightful as usual but I think you Florida West Coasters do not take into account the effect the Gulfstream has on our area.

Fastfeat/Ken, You are fast as hell!

Bottom-line- USDA Zones are plane crashes  and should no longer be recognized by civilization. This includes the Florida folks in Miamah that are supposedly in Zone 11.Happ, one side note-the only way I can get 40 degrees F. from here in 15 minutes or less is in a Gulfstream or Citation vertical/ballastic.

Share this post


Link to post
Share on other sites
spockvr6

(bubba @ Oct. 15 2007,09:42)

QUOTE
Bill and Larry,Insightful as usual but I think you Florida West Coasters do not take into account the effect the Gulfstream has on our area.

No doubt that Gulfstream has an effect.

Between that and the way the fronts tend to come down (at an approximate 45 degree angel from the NW), its easy to see how in SFL, the equivalent latitude can stay warmer on the east coast than on the west.  

The record low temperatures display this as well.  Take a peek at the all time record low of the Flamingo Ramger Station on the southwest tip of the state.  25F!

Share this post


Link to post
Share on other sites
happ
Happ, I am incorrigble but it takes alot to get you California folks to open up to the rest of the world. It seems you have to throw a little dynamite stick at you to even get your attention.I do stand by my statement that there are no ZONE11 climates in California

Have no idea what you are talking about [is this some sort of Florida versus California hang-up?  ???

You can believe whatever you want; maybe someday you will publish your "contentions" [perhaps the "World is Flat Society would be interested  :laugh: just playing

Share this post


Link to post
Share on other sites
elHoagie

(bubba @ Oct. 15 2007,06:42)

QUOTE
or LA when it hit 23 degrees F.

Jack,Same straightforward coherency but once againSan Diego's 10 year average is too short for Zone11.

Bubba,

I'm not sure where you found 23F for LA.  For a brief paper I wrote for the SoCal "Palm Journal" I used all of the historic NOAA publications to determine the yearly low for various places in SoCal going back 100 years (to 1907).  During that time the lowest temperature in downtown LA was 28F, and subfreezing temperatures occurred 4 times (once every 25 years on average).  

Since the USDA bases zones on a 10 year average, I did the same.  Still, using the data I found, the 100 year average low for downtown LA and San Diego is the same, 38F.  Although that isn't zone 11, it's pretty close....

Jack

Share this post


Link to post
Share on other sites
happ

As a serious weather cadet [actually climatology] data has been collected/analyzed since 1980.  It is also a good sampling of my immediate area of Mt Washington/Highland Pk/El Sereno where I have lived.

The only freezing temp recorded in 27 yrs was on 12/23-24 1990 30F-1.1c What's ironic is that I was living down in Aldama canyon at that time [30 feet above the dry creek.

It was the first time I observed ice in a swimming pool & have photos of it  :P    

Here are the years/coldest temps/number of nights  below 40F/4.4c since 1980:

1982: 37F [once

1987: 37F [twice below 40F

1990: 30F [5 below 40F, it was quite a year  :(

1998: 38F [once

2001: 39F [twice below 40F

2002: 39F [once

2007: 37F [twice below 40F

This website is making me work  :laugh: [i still haven't transferred all my written data - a tedious job

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...