CNN is reporting on TV that “many firefighters say fires burn hotter than they used to.”
Apparently the heat of combustion of wood has changed, most likely accompanied by the a change in the weight of ducks.
BEDEMIR: What makes you think she is a witch?
VILLAGER #3: Well, she turned me into a newt.
BEDEMIR: A newt?
VILLAGER #3: I got better.
VILLAGER #2: Burn her anyway!
CROWD: Burn! Burn her!
BEDEMIR: Quiet, quiet. Quiet! There are ways of telling whether she is a witch.
CROWD: Are there? What are they?
BEDEMIR: Tell me, what do you do with witches?
VILLAGER #2: Burn!
CROWD: Burn, burn them up!
BEDEMIR: And what do you burn apart from witches?
VILLAGER #1: More witches!
VILLAGER #2: Wood!
BEDEMIR: So, why do witches burn?
[pause]
VILLAGER #3: B--... 'cause they're made of wood...?
BEDEMIR: Good!
CROWD: Oh yeah, yeah...
BEDEMIR: So, how do we tell whether she is made of wood?
VILLAGER #1: Build a bridge out of her.
BEDEMIR: Aah, but can you not also build bridges out of stone?
VILLAGER #2: Oh, yeah.
BEDEMIR: Does wood sink in water?
VILLAGER #1: No, no.
VILLAGER #2: It floats! It floats!
VILLAGER #1: Throw her into the pond!
CROWD: The pond!
BEDEMIR: What also floats in water?
VILLAGER #1: Bread!
VILLAGER #2: Apples!
VILLAGER #3: Very small rocks!
VILLAGER #1: Cider!
VILLAGER #2: Great gravy!
VILLAGER #1: Cherries!
VILLAGER #2: Mud!
VILLAGER #3: Churches -- churches!
VILLAGER #2: Lead -- lead!
ARTHUR: A duck.
CROWD: Oooh.
BEDEMIR: Exactly! So, logically...,
VILLAGER #1: If... she.. weighs the same as a duck, she's made of wood.
BEDEMIR: And therefore--?
VILLAGER #1: A witch!
Ah… Python. When it’s not making you laugh, it’s eating your kids.
And water boils hotter and ice freezes warmer today.
These are only plausible explanations for the upward adjustments of modern urban heat island temperatures and the downward revisions of historical temperature data by NASA.
Well if hurricanes can have a category 6, fires can burn hotter.
Call it Mannian physics with a Gorecle twist.
This is overgeneralizing Spin
Fire behavior triangle is Fuel, Topography, Weather
If the fuel is drier, the fire behavior will be more extreme- some areas have indeed had 2 dry winters in a row, leading to unusually dry fuels and soils and consequently extreme fire behavior.
So if they mean 1 or 2 years ago by “used to”, then CNN may be reporting accurately. The winters before those were, however, some of the wettest winters on record…so if by “used to” they mean more than 2 years ago, that would be incorrect.
And then again, only in those areas that had the consecutive dry winters.
And the wind speed can make a fire burn hotter too.
But these anonymous firefighters’ anecdotal observations don’t mean much and amount to a hill of beans – and they would give even more wind to fan the fires.
I picked up a young lady once. She told me she was a witch and could make me turn into anything she wanted. I told her I did not believe her, but sure enough she made me turn into a motel!
Ah, but you only stayed there for a short spell.
Unfortunately, had this been a true story, my stay would have been relatively much too short.
It’s true, fires do burn hotter.
This video, made by NIST (National Institute of Standards and Testing) shows the danger of “modern” fires compared to the danger of fires occuring 40 years ago. Keep your eye on the clock!
The room on the left is furnished with old fashioned furnishings, made mostly with natural materials (wood, cotton, wool, silk, etc).
The room on the right is furnished with stuff made largely with synthetic material. Most synthetics are petroleum based. Think of them as frozen gasoline….
http://www.youtube.com/watch?v=aDNPhq5ggoE
Actually – modern clear cut GENx forests are designed for rapid growth using trees that are not genetically adapted to an area, and are known to have tree ring gaps measures in furlongs, hence the popularity of chip board. I would not be surprised to learn these instant trees burn like gasoline but being a skeptic I’d like to see some old growth burn tests along side new growth burns. I’ll bring the corned beef and ribs.
The temperature of a wood fire depends (amongst other things) upon its moisture content.
The Combustion Process of Burning Wood
Wood heats up to approximately 212 oF (100 oC) evaporating the moisture in it. There is no heating from the wood at this point.
Wood solids starts to break down converting the fuel gases (near 575 oF, 300 oC).
From 575 oF to 1100 oF (300 – 593 oC ) the main energy in the wood is released when fuel vapors containing 40% to 60% of the energy burn.
After burning fuel vapors and evaporated the moisture, only charcoal remains burning at temperatures higher than 1100o F – 593 oC
http://www.engineeringtoolbox.com/wood-combustion-heat-d_372.html
Another way this could be true is if you consider the amount of burning material in a given volume. If there is a higher density of smaller trees burning, then the temp they produce would be higher than a low density of larger trees.
I disagree. Wood has water in it in two forms – native water in the cells, and the “hydro” part of carbohydrates that the cell walls are made of.
The more water, the cooler the burn. So, living trees burn cool (relatively). Dry wood burns hotter (less native water), and charcoal burns hottest. (In charcoal, the carbohydrates have been reduced to carbon, and when carbon burns it doesn’t produce water.)