On Thu, 20 Mar 2008 14:09:35 +0100, Mxsmanic
wrote:
>EvelynVogtGamble(Divamanque) writes:
>
>> Have you ever spent any time at all in an adobe structure from the
>> early days of the Southwest?
>
>Yes. As you observe, in the open desert, it can stay cool during the day ...
>but only because the nights are cold. Essentially, it smooths out the ups and
>downs of daily temperature variations. However, if it is hot 24 hours a day,
>as it is in Phoenix today, a structure with thick walls serves no purpose. It
>will still become hot inside.
>
>> "Delay" may be all that's needed, when the
>> nights are cold and the days hot.
>
>Unfortunately, in Phoenix, the days AND the nights are hot.
See my previous post on diurnal range. Today's range in Phoenix
will be 83F high and an ovenight of 52F. While Phoenix has messed
up its atmosphere enough to restrict it's diurnal range somewhat,
that's still pretty respectable. In the summer it might be
typically 110F for the day's high with an 80F nightime temp. 80F
(27C) might seem warm to those who live in more humid climates,
it can feel downright chilly here in the desert. In any case, 80F
is not "hot".
I remember one evening my wife and I were sitting out on our
patio and there was slight breeze. We commented that it seemed
kind of chilly, but a glance at our patio thermometer showed it
was nearly 90F giving us considerable amusement.
Monsoon season can be more problematic; the increased atmospheric
humidity reduces heat radiation to space making the nights more
humid and higher temp. Fortunately, monsoon season lasts from
about 15 June to 15 Sept, and the worstof the humidty is perhaps
20% of that time.
I lived here in Tucson for over a decade without refrigerated air
conditioning, and evaporative coolers ("swamp boxes" are worse
than useless since they add humidity to your room ( a deirable
characteristic during the hot, dry days of May and June). On the
other hand, at no time during a monsoon season did I feel as
uncomfortable and unable to sleep as I had on hot summer nights
in Ohio without any air conditioning.
Consider, for instance, that the the onset of the monsoon season
required a dew point of 54F (12C)for three days. So at 90F (32C)
the relative humidity will be about 37%. This isn't exactly
sweltering humidity. Of couse, at times the dew point goes higher
than that, but we like to joke about the fact that the humidity
goes up to about 50% when it's raining.
Still, we're so used to humidity under 10% that 50% can seem
downright sweaty.
--
************* DAVE HATUNEN (hatunen@cox.net) *************
* Tucson Arizona, out where the cacti grow *
* My typos & mispellings are intentional copyright traps * |