Bushwalk Australia

This morning answering a question regarding "4 season tents" it occurred to me that maybe some of the side effects of condensation are overlooked.
Typically people want maximum wind protection , that often means lack of ventilation.
If the tent design impedes good air flow we get condensation. The aspect that interests me in this is that above a certain temperature , from 20c up in particular, we feel warmer as the humidity level raises (say 32c in Bali at 90% humidity feels warmer than 32c in Melbourne at 60% ...) but below about 10c it has the opposite effect, it cools us down quicker.
So given that "wind chill" does not affect inanimate objects (ie it cannot cool your sleeping bag if the fabric is wind proof) from my point of view more air flow is better than a "more protected" environment.
BTW, a double skin tent may prevent you from noticing condensation, but it will not prevent your clothing and sleeping bag from doing so.

One index that takes humidity into consideration is ReelFeel by AccuWeather.
See :
http://www.accuweather.com/help.asp
Any thoughts ?
Franco

Do they have data for out of the way places?

Local conditions in the bush are hard to predict. 2 sites 10m apart can be quite different. You can choose a protected site, but that doesn't guarantee that your tent won't get buffeted by wind due to high speeds or direction change. I suspect that in still conditions, moist ground between the fly and the tent may have more effect than how much huffing and puffing you do - due to local high humidity in the enclosed space. Ideal setup is really a tent that has good adjustable ventilation and an owner that understands what's going on. Personally, I don't mind a light breeze, especially if it minimises packup time in the morning but I draw the line at a gale through the tent - you need to be able to batten down the hatches...

Yes , good point about ground evaporation. Small solo tents with a large vestibule tend particularly to suffer from that. Worth using a piece of ground cloth even to cover just that bit .
Franco

Franco wrote:One index that takes humidity into consideration is ReelFeel by AccuWeather.

The accuweather index is interesting but still will be somewhat subjective to the actual people involved and how they rate the relative effect of different factors (like windchill, humidity ..) It would also be know how they deal with the idea of humid cold that you mention because AFAIK its not a concept that is understood very well.

Franco wrote:So given that "wind chill" does not affect inanimate objects (ie it cannot cool your sleeping bag if the fabric is wind proof) from my point of view more air flow is better than a "more protected" environment.

While a sleeping bag does not 'feel' windchill, more heat will be lost when it is windy than when it is not. The rate of heat passed out from your body is proportional to the temperature difference inside and outside the bag. If there is no wind, the air temperature on the surface of you bag will be greater than the air temperature in free space, because this air is heated by your body. Whether or not the effect of this would actually be noticed is questionable. You will basically always loose heat through your head anyway.

Franco wrote:This morning answering a question regarding "4 season tents" it occurred to me that maybe some of the side effects of condensation are overlooked.
Typically people want maximum wind protection , that often means lack of ventilation.

In a double skin tent, the inner will be sealed from the wind, allowing for more ventilation of the fly, hence reducing the humidity (and hence condensation) inside the tent. In this sort of tent, wind protection means stability and cover from blown rain at odd angles.

One day I might find again the formulas for heat sink size and the effect installing a fan has. From memory there was a dramatic saving in heat sink size compare to a rather small fan. Much the same with wind blowing through a tent. For example I froze at Frycient at sea level in a part inner mesh tent and was drench by condensation as well. Yet in the same bag camping on three or more feet of snow with snow falling during the night was comfortable once I put more air in my sleeping mat.

Interesting the tent with mesh does not have a ground sheet while the other ones do so might be ground condensation is more an reason for condensation than we give it credit.

Frankly for Tassie I would be very wary of any tent that did not have at least bathtub type protection from the wind. And as mentioned numerous times I would shy away from any design that does not have vents high up in the fly. Looking at a lot of newer designs or reworking of classic designs I can not but help notice the absence of many features such as vents and pole sleeves. Have these been sacrificed on the alter of weight saving or cost cutting is a "mute/moot" point as the result is the same.

Cheers Brett

Brett wrote:"mute/moot" point

I sense the indecision is strong with this one.

photohiker wrote:

Brett wrote:"mute/moot" point

I sense the indecision is strong with this one.

Interesting thing the English language. Both have distinct meanings but effectively mean much the same, i.e. "does matter what you say it ain't going to change so you might as well be silent (mute)

Cheers Brett