> Not to be contrary, Russell, Contraryness is always welcome :-) But I can be happy with non-contraryness too. > but the data seems to be very compelling for > some and hardly impressive for others within the community of scientists. > This is not the case for gravity, or electric field, etc. How can it be a > sound principle if there is so much controversy, and there is clear > definition of its nature? Second things first. 2. The definition is far from clear. This is outlined nicely in the summary of an ebook in one of the references I gave and in various papers. People are agreed that the climate is varying. Some say we are driving it towards a warming cycle. Others say we are pushing it towards triggering an ice age. Some, wisely, say that that A MAY cause B. Some say that's just the way it goes and we are not having a significant effect. The most alarming of the true scientific positions is that we MAY be pushing the climate into a toggling mode where it changes almost instantly into a completely different way of working - past history seems to indicate you MAY be able to swing mean global temperature by over 15C in around 50 years. Now THAT would be a time to live through (if you were lucky :-) ). Note that Northern Summer 2003 was the hottest ever recorded. (I was there at the peak - it was very interesting). Note El Ninya weather patterns of a decade or two back - never *known* to have been seen before. And changes since. Some say we are doing this. others say it just happens. 1. We don't know enough, the reality is vastly complex, our computers and our knowledge cannot model the system well enough to be certain that our assumptions are good. Some people just decide that they know their assumptions are the correct ones, and away we go. They MAY be right. They may not. God knows who is right. Just as well ;-) While gravity and electric fields are at core a pure mystery (even though we may pretend otherwise), we can model their effects very very very well indeed. In fact our models work better than we can measure reality and we have cause to believe that our models are far better than our measurements. eg Gravity seems to work by inverse law to power 2.000000000000000000000000000000..... . Our measurements run out long before the 0's do. Fundamental laws generally allow of good prediction and modelling, even if we don't understand how they work. Even Quantum mechanics, which we completely don't understand, is superb for predictions (most of the time until we find another wrinkle). But atmosphere is not based on simple single fundamental laws but on vast interactions (obviously enough). The only computer we have that will model it accurately is an analog one and its in constant use for other purposes and only gives results in real time. Maybe we could ask the mice to fund a second one ? Russell McMahon Did I pass ? ;-) -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body