[Geology2] Re: your opinions

Those precessions of the poles and the eccentricity of the earth's orbit have affected earth's climate in cycles for the whole history of the planet. The climatic changes result in periodic fluctuations of sea level and the height of tides on a regular, long term schedule and we can see the affects of that in the rock record. It shows up most obviously in cycles of deposition where a sequence containing several different types of rocks is repeated upward.

The subject is pretty techie, but if you want to get an idea of what the they are talking about you can take a look at this article:

http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3091.2011.01255.x/abstract

--- In geology2@yahoogroups.com, John Rasmussen <john@...> wrote:
>
> not to mention the precession of the poles, which also has a great effect
> on the climate. and just for the fun of it, what is the effect of the
> reversal of the poles? There are many other things that will effect
> climatic change other than CO2 levels in the atmosphere. Until we can
> integrate all the possible causative agents, and formulate a conclusion
> that fits ALL the data, we really don't have any idea what will happen.
> and then it will be a theory, as there will always be the possibility that
> a datum will be found that won't fit.
>
> John
>
> John
>
>
> On Tue, Aug 20, 2013 at 10:25 PM, fossrme <fossrme@...> wrote:
>
> > **
> >
> >
> > This is a great description of dating with tree rings! Would you mind if I
> > posted it on the Panentheism Group where we've talked about the subject
> > recently?
> >
> > As an aside on this topic I have two pieces of very impressive silicified
> > wood from a place somewhere in western Wyoming. They are sections of broken
> > branches about 5 inches long and 1 inch wide, that are so perfectly
> > preserved in color and texture that they could easily be taken for modern
> > woody fragments until they are lifted. The bark is partly scaled off on
> > one, which adds to the realism. Unfortunately they don't show any internal
> > rings, because they were formed as simple cavity fillings after the wood
> > disappeared. But some of the petrified wood in the western US was created
> > by replacement of the wood by silica on a molecular scale, and the rings
> > are well preserved. Have you heard of any use of rings in fossilized
> > material for dating purposes? Just curious.
> >
> > Below, you say, "No one seriously denies that CO2 levels affect
> > change". I am sure that is true for those who have looked into the science
> > seriously, but not so sure it is the case for people who haven't. We have
> > nearly 900 members in our group, which is devoted primarily to geology, and
> > I have no idea of their range of interest and level of knowledge on the
> > subject of climate change. So much disinformation and distortion have crept
> > into this area that I think it is useful on occasion to go back and restate
> > that basic relationship that is at the core of AGW, and how we know that it
> > exists.
> >
> > The trapping of heat by CO2 is only the starting point of a process that
> > includes many other modifiers, some quite powerful in their own right, but
> > if we are not clear on that starting point, the rest of it is always in
> > question. Maybe the few words I had to say were too basic for this group,
> > but they can also be a starting point for anyone who wants to add more. In
> > another post Eman provided some very informative details that help in
> > building a mental and visual framework for what happens during the process
> > of warming.
> >
> > My last sentence there "So the question for me has
> > always been, how can the atmosphere not heat up as CO2 levels rise" simply
> > poses the question of what other forces could act to counter the warming
> > from CO2.
> >
> > > I kind of like the idea of us all living in a pre-industrial age but
> > with all the benefits we have today :-).
> >
> > Hmm. There's one to think on. A pre-industrial age with cars, televisions,
> > modern medicine and twitter. Yeah!!! Do you suppose people were happier in
> > the old days?
> >
> > Your experience in the climate business makes it sound pretty cut-throat
> > and cynical. Maybe because it is so competitive? I'm glad I haven't been
> > involved in that area. There are so many ego issues there, and
> > intellectuals of all kinds tend to believe that their beliefs are their
> > identity. Not that everyone, or even the majority are that way, but it is
> > hard not to in this world anyway, and that culture seems to foster it.
> >
> > Clay
> >
> >
> > --- In geology2@yahoogroups.com, Tricks <richard.tyndall@> wrote:
> > >
> > > Home now so happy again. :-)
> >
> > >
> > >
> > >
> > > In theory if you have enough of a sample of wood in a particular area
> > then
> > > you can get an absolutely accurate date. Basically all the trees in a
> > region
> > > sharing similar climatic conditions should exhibit similar growth
> > patterns
> > > each year depending on the annual changes in temperature, rainfall, light
> > > and whatever else affects growth.
> > >
> > >
> > >
> > > So within the UK they archaeologists have now built up a record of tree
> > > rings that goes back well into the Mesolithic (around 6000 BC) and it is
> > > possible to match any given pattern to that record and come up with a
> > date.
> > > When they discovered Sea Henge off the coast of Norfolk a few years ago
> > they
> > > were able to use tree rings to date the structure to not only a specific
> > > year but even the season. This was not based just on the dendro date but
> > > combined it with RC dating and also Bayesian Mathematics which is a
> > > statistical technique which is being widely used in archaeology in recent
> > > years to tighten up on RC dates.
> > >
> > >
> > >
> > > We use dendro dates to calibrate Radio carbon (RC dates) as the amount of
> > > carbon of the various isotopes in the atmosphere is not as fixed as
> > people
> > > first thought when the system was devised. As a rule if you see a date
> > that
> > > has a small `bc' it will be an uncalibrated RC date and if it has a big
> > `BC'
> > > then it is a calibrated date. This can be very useful to know when
> > looking
> > > at dates for stuff as it is often not made clear by authors which dates
> > they
> > > are using.
> > >
> > >
> > >
> > > The question of CO2 levels and its relationship to temperature is not
> > quite
> > > as clear as you set out. No one seriously denies that CO2 levels affect
> > > change. That is not where the controversy lies (except perhaps amongst
> > the
> > > creationists who deny everything scientific). The question of impact is
> > > primarily concerning feedback mechanisms and whether the positive
> > feedback
> > > mechanisms outweigh negative feedback mechanisms. That is where the
> > > modelling arguments come in and where the real controversies lie.
> > >
> > >
> > >
> > > Personally I am a bit of a sad greenie and old hippy on most things. I
> > kind
> > > of like the idea of us all living in a pre-industrial age but with all
> > the
> > > benefits we have today :-). But my own concerns about the line being
> > taken
> >
> > > by some (though not all) AGW advocates came about when some prominent
> > voices
> > > decided that many of the events I had studied in depth for much of my
> > life
> > > such as the Bronze Age, Roman and Medieval Warming periods simply hadn't
> > > happened. Once they were challenged on this they then changed their
> > position
> > > and claimed that they had happened but had not been worldwide and so
> > didn't
> > > count. Now we are finding that they were indeed worldwide it needs some
> > > reassessment of their positions. I don't think this necessarily changes
> > much
> > > in the overall picture and doesn't prove or disprove anything but it
> > > certainly gave me serious pause for thought about the honesty of some of
> > the
> > > people concerned when it appeared they were trying to railroad events
> > out of
> > > existence to improve their arguments.
> > >
> > >
> > >
> > > Richard
> > >
> > >
> > >
> > > _____
> > >
> >
> >
> >
>
>
>
> --
> John Atwell Rasmussen, Ph.D., AJP
> Rasmussen Gems and Jewelry LLC
> <http://handmadeartists.com/shop/rasmussengems>
> "A Time to Stop Living at Work; A Time to Start Working at Living."
>




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