Some supporting research conducted at New York City follows the news item below. h/t to WUWT reader Phil (not the grouchy one) -A
Heat islands: Cities heat quickly, cool slowly
By DEEPTI HAJELA
Associated Press Writer
NEW YORK (AP) — Hot town, summer in the city? No kidding.
The high temperatures blanketing the Northeast and mid-Atlantic regions of the country are making many people miserable, but those in New York City, Philadelphia and other dense, built-up areas are getting hit with the heat in a way their counterparts in suburbs and rural areas aren’t.
Cities absorb more solar energy during the day and are slower to release it after the sun sets, making for uncomfortable nights and no real relief from the heat. And because they haven’t cooled down as much overnight, mornings are warmer and the thermometer goes right back up when the sun starts beating down the next day.
Scientists have known for years about so-called heat islands, urban areas that are hotter than the less-developed areas around them.
Cities are just “not well designed to release that summertime heat,” said William Solecki, geography professor at Hunter College and director of the City University of New York’s Institute for Sustainable Cities.
The lack of nighttime relief can make the daytime high temperatures even more difficult for people to take as the days pass and the heat continues, he said.
That’s “where you start to have real problems, if your body’s not cooling down,” Solecki said. “You’re not getting that break.”
Deaths blamed on the heat included a 92-year-old Philadelphia woman whose body was found Monday and a homeless woman found lying next to a car Sunday in suburban Detroit.
The heat-islands effect is significant in the East because “we have a large population living in heavily built-up areas with lots of concrete and lots of steel, good absorbers of heat,” National Weather Service spokesman Sean Potter said.
full story here at Tampa Bay Online
=================================================
Here is some supporting research from NASA (not NASA GISS).
Keeping New York City “Cool” is the Job of NASA’s “Heat Seekers”
Jan. 30, 2006
The “heat is on” in New York City, whether it’s summer or winter. This is due to a phenomenon called the urban heat island effect that causes air temperatures in New York City and other major cities to be warmer than in neighboring suburbs and rural areas. And, in a big city, warmer air temperatures can impact air quality, public health and the demand for energy.
Image to right: A thermal satellite image of New York City captured by NASA’s Landsat satellite on August 14, 2002 at 10:30 a.m., shows the locations of the warmest air temperatures as seen in red. The blue indicates areas with cooler air temperatures. Click on image to enlarge. Credit: NASA
Recently, several innovative approaches developed by scientists, public officials, environmental activists, community organizations and others have been put in place to take a bite out of the Big Apple’s temperature problem. NASA researchers, using NASA satellite observations, weather pattern data and computer models, have recently assessed how well those strategies are working. Their study results will be discussed during the 2006 American Meteorological Society’s annual meeting in Atlanta, Ga., Jan. 29 through Feb. 2.
“We need to help public officials find the most successful ways to reduce the heat island effect in New York. With ever-increasing urban populations around the world, the heat island effect will become even more significant in the future,” said Stuart Gaffin, an associate research scientist at Columbia University, New York, and a co-author of the new NASA study. “The summertime impacts are especially intense with the deterioration of air quality, because higher air temperatures increase ozone. That has health effects for everyone. We also run an increased risk of major heat waves and blackouts as the heat island effect raises demand for electricity.”
In cities, the urban heat island effect is caused by the large number of buildings, sidewalks and other non-natural surfaces that limit the amount of land covered with vegetation like grass and trees. Land surfaces with vegetation offer high moisture levels that cool the air when the moisture evaporates from soil and plants.
Image to left: This image indicates case study areas in New York City used in the NASA study, and weather stations. Click on image to enlarge. Credit: NASA
In large cities, land surfaces with vegetation are relatively few and are replaced by non-reflective, water-resistant surfaces such as asphalt, tar and building materials that absorb most of the sun’s radiation. These surfaces hinder the natural cooling that would otherwise take effect with the evaporation of moisture from surfaces with vegetation. The urban heat island occurrence is particularly pronounced during summer heat waves and at night when wind speeds are low and sea breezes are light. During these times, New York City’s air temperatures can rise 7.2 degrees F higher than in surrounding areas.
In the recent project, NASA researchers set out to recommend ways to reduce the urban heat island effect in New York City. They looked at strategies such as promoting light-colored surfaces such as roofs and pavements that reflect sunlight, planting “urban forests” and creating “living roofs” on top of buildings where sturdy vegetation can be planted and thrive. Using a regional climate computer model, the researchers wanted to calculate how these strategies lower the city’s surface and close-to-surface air temperatures and what the consequences of these strategies would be on New York’s energy system, air quality and the health of its residents.
The researchers conducted a city-wide case study over the summer of 2002 to measure changes in air temperatures. They also used six smaller case studies during the same period in places like Lower Manhattan, the Bronx’s Fordham section, Brooklyn’s Crown Heights section and the Maspeth section of Queens. The areas were chosen for the different ways land is used and their nearness to areas with high electrical use. They also had warmer-than-average near-surface air temperatures called “hot spots” and boasted available spaces to test ways to reduce the urban heat island effect.
“We found that vegetation is a powerful cooling mechanism. It appears to be the most effective tool to reduce surface temperatures,” Gaffin said. “Another effective approach is a man-made approach to cooling by making very bright, high albedo, or reflected light, on roof tops. These light-colored surfaces, best made using white coatings, reflect the sun’s light and thereby, its heat. Interestingly, more area is available to create the lighter surfaces than to add vegetation in a city such as New York.”
This project is being conducted by and funded by the New York State Energy Research and Development Authority (NYSERDA). For more information on the NYSERDA’s Environmental Monitoring, Evaluation, andProtection (EMEP) project, please visit on the Web: http://www.nyserda.org/programs/Environment/EMEP/project/6681_25/6681_25_pwp.asp.
Reference
Rosenzweig, C., W. Solecki, L. Parshall, S. Gaffin, B. Lynn, R. Goldberg, J. Cox, and S. Hodges 2006. Mitigating New York City’s heat island with urban forestry, living roofs, and light surfaces. Presentation at 86th American Meteorological Society Annual Meeting, Jan. 31, 2006, Atlanta, Georgia.
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ONe thing I found interesting from the landsat image was, even in an area as heavily developed as NYC, the hottest locations were still the airports. Both JFK and LaGuardia have the deepest reds visible in the photo.
zilla,
looks like you are new here.
welcome. if you stick around, you will find that
1: most folks here are fair
2: and they are smart and generally sort through multiple causes & effects.
and yes, everyone knows weather is not climate.
And that’s why in many central european villages grapevines have been grown to cover south facing walls for centuries. In the summer the leaves shade the walls and help to cool the house by evaporation. In the winter the leaveless vines let the sun through to help warm the walls. And in the fall you can harvest the grapes to make the wine that helps you get through the winter. One old vine that covers a medium sized 2-story house can produce up to 300 Liters of wine/year.
Show me another air-conditioning system that can do that.
gary gulrud says:
July 8, 2010 at 1:40 pm
“This January through June has been a record setting period according to those satellites. That is the GLOBAL PERSPECTIVE”
That is also a very short-term perspective, i.e., not climate, comprende?
VILLABOLO:
“ERES TU QUE NO COMPRENDES.
Why are you emphasizing longer term climate than the one I Mentioned when the CONTEXT was the cherry picked REGIONAL climates such as Australia and the Eastern states? Do you “comprende” that the very topic of this thread is, to put it in your own words, “. . . a very short-term perspective . . .” in both time and space?
You can actually measure the difference very roughly using a car with an inbuilt thermometer that measures outside air temps. I have noticed in the city of Memphis a 3c difference from the city centre to the edge of the city where I live on sunny days. Try it for yourself it gives you an idea of how much of a difference there is.
tarpon says:
July 8, 2010 at 11:59 am
I’m really getting tired of seeing that link. SB is merely an equation tying together temperature, surface (emissivity), and flux. If you want to include thermal inertia, it takes more physics and heat transfer away from or to the surface.
Somehow I got the wrong link into the Phil Jones article. Here it is:
http://www.agu.org/pubs/crossref/2008/2008JD009916.shtml
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 113, D16122, 12 PP., 2008
doi:10.1029/2008JD009916
Urbanization effects in large-scale temperature records, with an emphasis on China
Urbanization effects in large-scale temperature records, with an emphasis on China
P. D. Jones
Climatic Research Unit, University of East Anglia, Norwich, UK
D. H. Lister
Climatic Research Unit, University of East Anglia, Norwich, UK
Q. Li
National Meteorological Information Center, China Meteorological Administration, Beijing, China
Global surface temperature trends, based on land and marine data, show warming of about 0.8°C over the last 100 years. This rate of warming is sometimes questioned because of the existence of well-known Urban Heat Islands (UHIs). We show examples of the UHIs at London and Vienna, where city center sites are warmer than surrounding rural locations. Both of these UHIs however do not contribute to warming trends over the 20th century because the influences of the cities on surface temperatures have not changed over this time. In the main part of the paper, for China, we compare a new homogenized station data set with gridded temperature products and attempt to assess possible urban influences using sea surface temperature (SST) data sets for the area east of the Chinese mainland. We show that all the land-based data sets for China agree exceptionally well and that their residual warming compared to the SST series since 1951 is relatively small compared to the large-scale warming. Urban-related warming over China is shown to be about 0.1°C decade−1 over the period 1951–2004, with true climatic warming accounting for 0.81°C over this period.
Nuke says:
July 8, 2010 at 1:52 pm
wayne says:
July 8, 2010 at 1:07 pm
Correction to wayne says: July 8, 2010 at 12:26 pm :
You can’t have it both ways, physics won’t allow it.
A quantum physicist might disagree with that.
LOL! Ok, you got me, I’ll bow to that!
In Rocky Mountain National Park, snow closed trail ridge road overnight.
George E. Smith says:
July 8, 2010 at 10:07 am (Edit)
The building I am working in right now; has both the heating and the air conditioning running all the time.
Is this some kind of integrated system which uses heat from the A/C exhaust to heat the parts of the building which are underground or something?
The IPCC will tell all those city dwellers that they are imagining the heat … after all, Phil Jones told them so.
“”” Dave Dardinger says:
July 8, 2010 at 10:37 am
George,
You say hot things don’t cool more slowly than cooler things, but that’s only true in one sense and not the one which is being talked about. It’s true that a hot object will release more heat and thus cool more than a cooler object, but the question at hand is how soon a given object will cool to a certain temperature (one that is comfortable to humans in this case.) For this question the answer is that a hot object will take longer than a cooler one to reach a given temperature.
Your other points have some validity, but if you work the numbers you’ll likely find the majority of excess heat at night in a city is from more difficult path heat must take to escape from the city rather than absorbing windows or AC venting. “””
So what you are saying Dave is; that hot things are hotter than cold things, and always will be; izzat about right ?
So why do the car companies make the radiators of their cars so hot; when the aim was to cool down the engine so it doesn’t melt. They even pressurize the water jacket to raise the operational boiling point of the cooling water, so it can carry off more heat.
Maybe we should be putting ice in our radiators, instead of hot water.
But the bottom line is Dave; there is absolutely NOTHING wrong with Urban Heat Islands. The crime comes in reading the Thermometer in the owl box in one of these heat islands; and then assuming that is a perfectly good temperature reading to represent some place that is 1200 km away from the thermometer; that is where the problem lies.
Anyone familiar with communication engineering; including high capacity digital data transmission, is fully familiar with the Nyquist Sampling theorem; which tells you how often; and at what intervals (in however many variables you have) you have to take samples, in order to be able to recover the original signal.
And in the world of climate; recovering the origininal signal doesn’t mean being able to replicate the original Temperature readings; but it does mean sampling at the correct intervals so that at least the average value (DC VALUE) of the function is recoverable. You only have to violate the Nyquist criterion by a factor of two in the direction of two low a sampling rate, in order for the spectrum folding caused by the aliassing noise; folds back all the way to zero frequency; which is the value of the function average that you were trying to determine.
Twice a day (min/max) temperature sampling; already violates Nyquist by at least a factor of two; so you cannot even recover the correct daily average temperature from a min/max regimen (the daily temperature cycle would have to be a pure sine wave to allow that). So who was it who said the temperature rises rapidly after sunup, and then decays slowly after sundown. Now hands up everybody who believes that is a description of a sinusoidal function. Ergo the daily temperature cycle is NOT sinusoidal; therefore it must contain at least some second harmonic component (12 hour period) since we are talking about a repetitive cyclic change here; so you need at most a six hour maximum time between temperature readings to be able to properly get the true daily average temeprature; min/max will not do that.
And let’s not even talk about the sampling errors in the spatial sampling. The total number of Temperature measuring stations in the Arctic (above +60 deg North Latitude); is not even enough to properly sample the Temperature map of a small area like the San Francisco bay area nine counties region or however many counties we actually have; so it is laughable to claim they are properly sampling the Arctic temperatures.
Oh I forgot to mention the clouds; how the hell do you get a true daily average temperature when you have clouds running around all the time, blocking out sunlight for minutes to hours. So it’s a joke to claim you are properly sampling even the true daily temperature of any single location; let alone the entire planet.
And if you could get the correct answer; it would be meaningless; because nobody has ever shown any causal relationship between the global mean temperature, and the net energy balance of the planet.
Other than that, I generally agree with your points.
“”” tallbloke says:
July 8, 2010 at 3:04 pm
George E. Smith says:
July 8, 2010 at 10:07 am (Edit)
The building I am working in right now; has both the heating and the air conditioning running all the time.
Is this some kind of integrated system which uses heat from the A/C exhaust to heat the parts of the building which are underground or something? “””
Not that I know of; that’s just the way it works; same goes for my automobile (Ford Taurus), if my AC is not turned down to the lowest setting, than both hot and cold are running together.
My son is a building (Plant) manager, who has to deal with those sorts of issues, and he says that system is quite typical; well at least in Silicon valley buildings. They mix hot air from the heater; with cold air from the refrigerator, since both of those things tend to produce air at just one Temperature either cold or hot; and the building Tempoerature control simply adjusts the air mixture to produce air at a set temperature. Depending on the ambient of course; the AC or the heater; will be cycling more or less often; so one will consume less power if it is needed less.
Office workers take a dim view of climate control systems; that simply blast freezing air or boiling air in bursts as needed in order to warm or cool their office cube; they want the air coming out of the system to be always at the comfort temperature; whatever that is set to.
Adn I believe you can prove on thermodynamic grounds; that when you mix cold air/water with hot air/water to reach some desirable Temperature set point; the resultant energy usage is higher, than if you simply supply enough heat or cold to counterract the ambient tendenccy.
The proper way to set the hot water heater in your house; is to adjust the hot water Temperature setting down until you can comfortably take a shower in hot water; with ZERO cold water running. Of course hopefully your dish washer has a built in heater; to cook the dishes at some autoclave Temperature.
If you have to mix cold water with your hot to get a comfortable shower; then your hot water setting is TOO HIGH.
And the lost heat due to having the hot water hotter than needed, and then pump it aound in pipes where it will lose more; also dictates that you should set the Temperature as low as it takes to comfortably shower in pure hot water with no cold.
Of course if you are like me; and take a cold water Navy shower instead; then you never find out how hot the hot water is; since you never have to use it.
I know this is off topic and I realize that these polls are worthless but MSNBC is running a poll on the public’s opinion concerning the vindication by the British panel of so the insultingly called “climategate” scientists.
WUWT is already on the warpath telling their members to chime in. The current results are 42% in our favor and 58% against.
http://msnbc.newsvine.com/_question/2010/07/07/4630892-are-you-satisfied-with-the-british-panels-conclusion-that-while-climategate-scientists-were-not-always-forthcoming-their-science-was-sound#comments
Dave Springer, thanks for the following quotation from Phil Jones:
“these UHIs however do not contribute to warming trends over the 20th century because the influences of the cities on surface temperatures have not changed over this time”.
Thanks also for the abstract to a Jones study in which he cites London, Vienna, and a Chinese city as part of his study. All of this makes me want to say three things to Phil. Number One, Phil, it is all in how you pick them. Neither London nor Vienna have experienced, since the end of WWII, the kind of increase in wealth experienced by most American cities. Neither London nor Vienna is adorned like a Christmas tree with air conditioners, dryers, and the many other baubles of modern technology. Those cities might show no UHI effect. But just try the average city in America, Japan, the Shanghai region of China, and all other places that have experienced revolutionary growth in wealth. Number Two, some cities cannot show a UHI effect because they are located in natural wind tunnels. Chicago is the best example, though Denver and many others pop to mind. In Chicago, the wind is always blowing and blowing hard off the lake. If you go downtown to celebrate the 4th, a coat and a blanket might leave you freezing your patootie off. I think your Chinese city fits in this category. Number Three, be precise about your measurements. After all, when measuring UHI we are dependent on measurement stations that might be years old or brand new. I could easily pick and choose measurement stations or make “adjustments” to all of them to show no UHI effect in St. Louis when there is overwhelming empirical evidence of a large UHI effect.
Finally, notice that Jones says “Both of these UHIs [London & Vienna] however do not contribute to warming trends over the 20th century because the influences of the cities on surface temperatures have not changed over this time.” Is this supposed to be an empirical claim, a universal generalization? Is he claiming that all of the heat coming from cities has not contributed to warming in the 20th Century? Please note that the claim is irrelevant to the question whether UHI exists. Please note that the claim, if true, makes the question of UHI quite unimportant to climate science. So, why is it in an abstract of a study done to show that there is no significant UHI effect? Why bother? Why not just explain that UHI, if it exists, is irrelevant to questions of global warming? Is this another case of Jones dreaming up another matter and tossing it out in case his criticism of UHI does not persuade us. If so, it is symptomatic of a serious problem.
@ur momisugly George E. Smith
July 8, 2010 at 3:38 pm
Now George, that’s a real efficient system (cough), run the heat and A/C at full tilt 24/7 and just adjust the mixture to get the correct temperature. Now if that accurately describes most high-rises no wonder this globe is using so much energy and office rent is through the ceiling!
( But I take it you surely jest, could your building manager just be off his rocker or maybe just lazy? )
Everyone talks about the weather, and it used to be the polite thing to do, starting conversations and such. Nowadays, we all still talk about the weather, but with supposedly “vilified” agendas.
By the by, what’s happening in the Northeast right now is weather, not climate. Give it another ten or so days………. This stuff happens all the time people!
Here in Florida we had a heat spell for a week in June with temperatures measured at my station in the ~98 degree F. range and heat indexes all the way up to 117 degrees F. Ten days later, 5-straight days of rain with max temperatures in the high 70’s~low 80’s (love that rain in the summer). Today, not a cloud in the sky and hot again, but not as much – 86 degrees and 96 heat index – it is what it is!!!!
Jose
Jose
KLA says:
July 8, 2010 at 2:12 pm
And that’s why in many central european villages grapevines have been grown to cover south facing walls for centuries. In the summer the leaves shade the walls and help to cool the house by evaporation. In the winter the leaveless vines let the sun through to help warm the walls. And in the fall you can harvest the grapes to make the wine that helps you get through the winter. One old vine that covers a medium sized 2-story house can produce up to 300 Liters of wine/year.
Show me another air-conditioning system that can do that.
___________________________________________________________________
HMMmmm, Great idea except my lawnmowers (goats & sheep) LOVE grape leaves. I have been harvesting wild grape leaves to feed a baby goat I have penned up. She lost her mom at 4 weeks of age and refuses to nurse from a bottle. (and yes she is doing just fine growing before my eyes)
The other problem with some vines is they do a lot of damage to the outside wall depending on the plant and the wall
@george Smith
To be fair, min/max should work fine if you’re looking for a trend instead of a near perfect measure of the average temperture. The climate boffins are very quick to point out that the story isn’t about whether the global average temperature was exactly 52F in 1980 and it’s exactly 53F today. The story is that it’s exactly 1 degree warmer now versus then. For the CO2 narrative to work the daytime maximums should be a tad lower while the night time temperatures should be more than a tad higher. This reflects the fact that CO2 in the upper atmosphere slows down daytime heating by absorbing IR coming in from above and radiating a portion of that back out into space while at night the CO2 in the lower atmosphere slows down night time cooling by slowing down IR from the ground trying to work its way back out into space. The difference that makes the average of the nighttime and daytime day higher is the conversion of visible wavelengths by the ground into infrared. CO2 is transparent to the visible wavelengths so during the day a majority of those (depending on albedo of the ground) reach the ground and heat it up. At night the stored heat is released at a frequency (or rather two narrow bands, three if you count a band that overlaps with water vapor) where CO2 is not transparent to it.
I think the climate boffins understand the physics of it at least this much. Few of the unwashed masses do even though anyone who got a passing grade in high school physics should be able to figure out how it works. An interesting phenomenon that emerges and is an acid pass/fail test for CO2 warming is that the lower atmosphere should be warmer and the upper atmosphere cooler as a result of CO2 greenhouse heating. If that isn’t true then CO2 ain’t the bogeyman. Changes in water vapor and cloud cover will leave a different fingerprint. If I’m not mistaken it’s been known for many years that the layers of the atmosphere aren’t behaving very much in the way of CO2 induced heating. Thus the climate boffins made up a story about a little extra CO2 causes a significant increase in water vapor and that extra water vapor is the culprit. The problem with that story is that if there’s a significant positive feedback from CO2 then it would drive a runaway greenhouse and in billions of years of the earth’s history there has been up to and over 10 times the CO2 concentration of today and there was never a runaway greenhouse. On the other hand, there have been plenty of runaway glaciations. The bottom line appears to be the climate boffins have the polarity sign wrong on the water vapor feedback mechanism. The suspicion amongst honest folks who understand all this is that clouds are the negative feedback. High white clouds that work just like painting your roof white does for the structure underneath – it reflects visible wavelengths of light before they get a chance to be absorbed by what’s underneath. The earth, it appears, has a rather fast acting thermostat limiting the maximum global temperature. The thermostat response on the minimum temperature on the other hand appears to be rather slow so we get global glaciations that last for tens of thousands or sometimes millions of years. Interestingly enough it’s CO2 that comes to the rescue, eventually, of a frozen earth. With the surface covered in ice the carbon cycle pretty much screeches to a halt. Over the course of geologic time volcanos continue belching out CO2 until its greenhouse effect is great enough to start thawing the planet. The thaw has a positive feedback associated with it so once it starts thawing it thaws fast and then the clouds quickly return to limit the maximum temperature, the carbon cycle returns with a fury, and all is well until the next runaway freeze.
More along the lines of cloud albedo being the negative feedback that comes with increasing CO2.
Unfortunately measuring the earth’s average albedo is something for which we have no paleo data to reconstruct its history. In the past decade there has been an ongoing study to track it by precisely measuring the brightness of the moon when it’s in the earth’s shadow and the only thing lighting it up is sunshine reflected from the lit portion of the earth (starshine is negligible).
Interestingly, there was a trend found but with less than 10 years of data any correlations with global average temperature are tenuous. The earth’s albedo has been rising. It went up about 1% in the past decade. That is what we would expect from a negative feedback mechanism associated with rising CO2. Unfortunately studies of high altitude cloud formation also indicate that solar magnetic field activity throttles them and there’s a fair amount of correlation with paleo-temperature reconstructions and several hundred years of more or less constant sunspot counting. This complicates the picture. There are about a zillion other complicating factors like amount of mixing of the vast cold deeps of the oceans with warmer surface waters and that is known to vary with periodicities ranging from years to (at least) decades.
The bottom line, near as I can figure, is that whatever global warming is driven by CO2 the signal is buried so far in the noise of those myriad other factors (some factors known and some unknown) it’ll never be pulled out of the noise with any degree of confidence.
NoAstronomer says:
July 8, 2010 at 1:41 pm
Wow! Just. Wow!
…
Well do you see that dark red blob in the lower right. Above and to the right of the nice blue, cool, islands of Jamaica Bay. That blob is JFK airport.
Ok, I see it, red JFK. But look at the red island at the top about 15 miles due north and to the east of the Queens. The red blob below the island is Laguardia Airport and I wonder what is on that Rikers Island just to the north that makes it so bright red (120+ºF). Mostly high-rises? I do see lots of asphalt. Most of the other islands are much cooler and tend to the blues. Are you that familiar with New York City?
Thanks Anthony, that is a cool (I mean hot) IR picture.
I have been bothered by this paper. How on Earth did they separate the solar heating from the heat released by energy usage, which we all know always eventually devolves into heat energy? I also am dubious about their assertion that cities absorb more solar energy than elsewhere. How can they determine that, in light of electrical usage being higher during the day when the Sun is up, both in doing business and air conditioning?
One of the biggest problems of climate science is separating the multitudinous factors involved. Here we have another example of specifically ignoring the real complexities and presenting a fabrication that sounds logical until you really think about it.
Or is this mostly elaborate opinion and spurious conclusions?
Gail Combs
Hop vines will work better than grape vines. They won’t damage the building because they don’t use tendrils. The downside is you have give them some strings running from the eve to the ground to climb otherwise you’ll get a ground thicket instead of a vertical sheet. If you live at a latitude higher than (IIRC) 35 degrees you can harvest the cones in the fall for beer making. Fresh hops are far superior to dried hops for the beer quality too. If you live further south than that the cones won’t set. They are long-day bloomers and if you don’t get over (again IIRC) 15 hours of daylight durin the year they’ll still grow fine but the cones won’t set. Hops are also extremely fast growers in the spring so by the time you want the full shade from them they’re providing it in spades. They die back to the ground in the fall and reemerge from the roots in the spring. They come in male and female flavors. Only the females produce cones. Propogation for cone production is only rarely done by seed but rather by digging up the thickened portions of the roots of females with known characteristics in the cones. The digging up is routine maintenance in hops farms as the thickened root nodes tend to spread out beyond the neat rows or circles from which want the vines to emerge. March – April is generally the time to buy your roots for planting. You need to order ahead as quantities are usually limited and they don’t store well. They can also be propogated by cloning of the desireable females but they’re very hard to find selling as potted clones.
Just some interesting trivia. I live too far south for cone set but I did consider them for the beneficial effect of shade on the house only in the summer. Harvesting the cones is quite labor intensive so be forewarned about that if you want to make some homebrew. You also need a few different varieties as few beers are made with a single variety of hops. My understanding is you add one kind early in the brew and another kind late in the brew.
Just for general information… the UHI effect where I live, as I measured it
the other evening was 4F at 0200 DST. Wind was SW at 7, humidity 82%.
My house is in a residential neighborhood less than 1 mi from the city limits.
I drove out into the country about 2 mi and then back to my house, so 3 mi overall. It was 80F when I left home and dropped to 76F just as soon as I left
town. I continued westbound for another 2 mi before turning around. Back at the house it was still 80.
The town I live in is in rural mid state Mo….population 2500. The nearest
towns are about 6 mi east and west with populations of less than 500.
Seems a town doesn’t have to be very large to exhibit the effect. In addition we are CONSISTENTLY 5 to 7 degF cooler than St. Louis which is about 50
air miles away. Oh! BTW the pavement temp in front of my house was still
88 deg F at 2 o’clock in the morning.
More info on earth albedo measurements:
http://bbso.njit.edu/Research/EarthShine/literature/Palle_Goode_2008_ASP.pdf
This is worth reading. It’s essentially a blunt indictment of the global circulation models that are being used to frighten the sheeple into global energy use governance.
Several key statements in it are:
1) There is no reliable way to accurately measure the earth’s albedo. The few methods being used are often in “unsatisfactory disagreement”.
2) GCMs assume that albedo is constant but the one conclusive thing found by experimental measurements is that the earth’s albedo varies a lot and it changes quickly.
3) GCM assumptions of albedo vary by as much as 7% from one model to another.
4) A variance of 7% changes the earth’s energy budget by more than all greenhouse gases combined!
Incredible. A climate forcing that can’t be accurately measured, that has an effect potentially greater than all greenhouse gases combined, and the global circulation models just throw a constant arbitrary number in there for it and then pretend like it isn’t a problem. I’m stupified. I mean I knew about the large effect that albedo can have but I wasn’t aware of the problems in measuring it with great enough accuracy to factor it into the GCMs for back-calibration.