Post by radiant on Sept 25, 2009 8:09:00 GMT
GLC for example has gone to some lengths to minimise the idea there was a little ice age that we can recover from
I haven't gone to any "lengths". I've challenged different posters to define the period of the LIA and the responses indicate a lack of consistency. You say the LIA existed but I'm not sure how you know since you have no trust in the thermometer record.
Can you tell how long the LIA lasted?
How can you be sure?
Do you have a theory for what caused the LIA?
Thermometers are probably not the best measure. How about skating on the Thames? Failure of harvests? Seems we can't measure temperatures accurately even today with thermometers.
In my view thats even our problem today. We have charlatans predicting doom and gloom and empirically we haven't seen zip. Hurricanes are down, tornados are down, sea level isn't visibly up (having lived on the Pacific ocean shore for 60 years), some years its still too cold (and sometimes too warm) for certain sealife. . . .any other negatives to look for?
Thermometers are an interesting example of how ignorant all of us are of the basics of this subject and how we all need to learn more about even the simplest concepts
Air for example does not radiate heat very well. So a ground based thermometer in still air (when it is often hottest by day) will be picking up a very small amount of heat energy from conduction of the air and the remainder from the radiation around it.
Thermometers therefore should be in standard white painted boxes and be calibrated and the recorded reading read from a calibration chart.
But there appears to be little standardisation in practice
1. The standard height of a box is a range of heights.
2. The frequency of painting appears unspecified?
3. The frequency of cleaning appears unspecified?
4. The boxes often house different equipment which may or may not alter the ability of the thermometers to receive additional radiation or less radiation from the sides of the box
5. The boxes are vastly different sizes so they can house the extra equipment being used by those who use the stevenson screens.
6. The boxes are often surrounded by vastly different materials
7. The location of boxes is not constant at one observing site
8. The paint has not been standard
Meanwhile the temperature change for the earth in the last 100 years is said to be 0.6 degrees.
Then there are other issues which are sort of mind boggling but which might be relevant
The temperature scale we are using is based on the triple point of water where water coexists as solid liquid and gas
But this temperature varies depending upon the isotopic composition of water
Water in lakes is enriched to be heavier water at the equator for example. In the oceans it is fairly well mixed. But even some of the labs measuring the national standards were using tap water as their source of 'Earths water'!
And the top UK government lab for example produced triple point cells for an international certification that had 'weird results' that nobody can explain.
Tiny difference perhaps or maybe not if exstremely high levels of cosmic radiation are present to alter the freezing point of precipitated water before people had the slightest idea such things were important? What is more many of the isotopes of water have fairly short half lives so the evidence is long gone after a few generations.
All in all a large number of variables and a proven record of ignorance of what temperature measurement actually means by human beings.
Then there is the curious revelations that people describing their data that they say accurately record temperatures dont want anybody else to review it for mistakes or as was demonstrated here on the board 'mistakes are impossible, the data is valid and it is time to end the bullshit'
Science in action.
If Science were working when people like Anthony Watts educated me and others to the problems associated with temperature measurment so that i went off learning what i did not know then i dont think we would see this kind of thing:
Instead there would be an appreciation of a point of view that was genuninely adding to our combined understanding of this subject.