Re: [asa] Subglacial Water System Moving Faster Than Previously Thought

*What you suggest as for the "appropriate" reaction to the current
> uncertainty reminds me of the reaction to Paul on Mars Hill.
Interesting. Let's discuss this some more.*
**
Well, I don't think that was how the Athenians reacted to Paul. Acts
17:32-34 says *"When they heard about the resurrection of the dead, some of
them sneered, but others said, "We want to hear you again on this subject".
At that, Paul left the Council. A few men became followers of Paul and
believed. Among them was Dionysius, a member of the Areopagus, also a woman
named Damaris, and a number of others." *So, some sneered, some seemed
genuinely interested but wanted to hear more, and some became believers.
Interestingly, we're not told exactly when those converts accepted Paul's
message; perhaps some were among those who wanted to hear more after Paul's
initial speech.
**
Anyway, this is sort of what I've been going on with Randy about -- the
question of authority. Paul was an Apostle commissioned by the Holy Spirit
to preach the Gospel to the Gentiles. The message he brought was a
proclamation of the one true God's exclusive claims to worship, made in the
context of Paul's Apostolic mission. The fact that this event was
enscripturated, given the context of Acts 17, suggests that there is
something normative in this account beyond its immediate
historical context. Arguably, it's a missiological model for the Church as
well as a general statement about the revelation of the one true God in
contrast to man-made idols.

Given all this, we can say that "let me study this some more" isn't a fully
adequate response to Paul's proclamation in Acts 17. Some people may need
time to hear more, but at some point everyone must make a decision about
whether to acknowledge the one true God. The reality is that no one is
justified ("justified" used here in an epistemic sense) in rejecting God's
exclusive claims.

I think you'd agree that the epistemic imperative must be different when it
comes to a scientific consensus -- right?

On 2/16/07, Rich Blinne <rich.blinne@gmail.com> wrote:
> This is in the overall context of underestimating the ice melt and a
number
> of unexpected, negative surprises. The IPCC acted appropriately in the
sense
> there is no consensus on this. The "this" here is not the consensus that
we
> will have an overall total 7m sea level rise in the business as usual
> scenario -- and that could be worse if there is significant ice melt in
> Antarctica which is not included in the 7m. The "this" is how fast we
reach
> the 7m equilibrium, centuries vs. decades. The effect we are discussing
> could speed up that process considerably but we just don't know.
>
>
> What you suggest as for the "appropriate" reaction to the current
> uncertainty reminds me of the reaction to Paul on Mars Hill. Interesting,
> let's discuss this some more. I'll take the passionate "need to know now"
> vs. the dispassionate "interesting question" any day. I'm sticking with my
> uh oh.
>
>
> On Feb 16, 2007, at 7:35 AM, David Opderbeck wrote:
>
> Ok - I'm not trying to play the skeptic here, and I confess ignorance
> of the primary literature, but it seems to me that a very recent
> discovery of this magnitude in relation to glacial stability is not
> really supportive of alarmism. On the one hand, you can say "this
> system may be even more fragile than we thought"; but OTOH, you can
> just as well say "this system seems very capable of handling melt
> water and runoff -- it's a much more flexible and dynamic system than
> appears on the surface." If we really don't know where between those
> two responses the truth lies, isn't the appropriate scientific stance
> a dispassionate "interesting question; let's try to find out" rather
> than necessarily an "uh-oh?" (And so the IPCC's stance is indeed
> vindicated at least as far as these data are concerned?)
>
> On 2/16/07, Rich Blinne <rich.blinne@gmail.com> wrote:
>
> This is recently discovered. The disturbing part is not the existence of
> this system, but the rapidity of the change and unexpected nature of the
> change over a period of months. The water acts as a lubricant and can thus
> act to accelerate deglaciation. Also, this change can both rapidly start
and
> stop, see
> http://sciencenow.sciencemag.org/cgi/content/full/2007/215/2
>
>
>
> Glaciologist Richard Alley of Pennsylvania State University in State
College
> agrees. "Lots of people were saying we [IPCC authors] should extrapolate
> into the future," he says, but "we dug our heels in at the IPCC and said
we
> don't know enough to give an answer." Researchers will have to understand
> how and why glacier speeds can vary so much, he adds, before they can
trust
> their models to forecast the fate of the ice sheets, much less sea level.
>
>
> The bottom line is the models for glaciers are not at all good and have
for
> the most part underestimated the ice melt. This was why this effect got
> completely pulled from AR4. We simply don't know but it doesn't mean we
have
> nothing to fear. Since this is so chaotic we may not know until it is too
> late. What we do know suggests that a rapid and catastrophic failure of
the
> arctic (and now antarctic) glaciers is very, very possible. We just don't
> know enough to effectively predict it. Think of it this way. The failure
> mechanism for the New Orleans levees was not effectively predicted, yet
they
> did in fact fail catastrophically. Glaciers may in an unpredicted fashion
> deglaciate rapidly in an analogous way as a levee failure where the
> structural integrity of the bottom is compromised. Thus, the uh oh.
>
>
>
>
> On Feb 16, 2007, at 6:27 AM, David Opderbeck wrote:
>
> Rich, was this subglacial water system recently formed, or has it been
> around for a long time and only been recently discovered? It seems that
if
> this is a recent phenomenon, it would perhaps be an "uh oh." If it has
been
> around for a long time and has only been recently discovered, however,
> couldn't that suggest that some fears about deglaciation are overstated --
> that glaciers are always very dynamic systems that aren't likely to
collapse
> catastrophically due to some kind of meltwater feedback loop? I'm
thinking
> of the scenes in An Inconvenient Truth concerning water on top of the
> glaciers in Antarctica (if I'm remembering this right).
>
>
> On 2/15/07, Rich Blinne <rich.blinne@gmail.com> wrote:
> >
> > From today's Science Express:
> >
> > http://www.sciencemag.org/cgi/content/abstract/1136897v1
> >
> > An Active Subglacial Water System in West Antarctica Mapped from Space
> > Helen Amanda Fricker 1*, Ted Scambos 2, Robert Bindschadler 3, Laurie
> Padman 4
> >
> > 1 Scripps Institution of Oceanography, University of California, San
> Diego, La Jolla, CA 92093, USA.
> > 2 National Snow and Ice Data Center, University of Colorado, Boulder, CO
> 80302, USA.
> > 3 NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
> > 4 Earth & Space Research, Corvallis, OR 97333, USA.
> >
> >
> > * To whom correspondence should be addressed.
> > Helen Amanda Fricker , E-mail: hafricker@ucsd.edu
> >
> >
> >
> >
> > Satellite laser altimeter elevation profiles from 2003-2006 collected
over
> the lower parts of Whillans and Mercer ice streams, West Antarctica,
reveal
> 14 regions of temporally varying elevation which we interpret as the
surface
> expression of subglacial water movement. Vertical motion and spatial
extent
> of 2 of the largest regions are confirmed by satellite image differencing.
A
> major, previously unknown subglacial lake near the grounding line of
> Whillans Ice Stream is observed to drain 2.0 km3 of water over ~3 years,
> while elsewhere a similar volume of water is being stored subglacially.
> These observations reveal a widespread, dynamic subglacial water system
> which may exert an important control on ice flow and mass balance.
> >
> >
> > Fast flowing subglacial ice streams are important indicators of climate
> change and will be helpful in improving our predictions of sea level rise.
> The author of this paper was quoted by New Scientist as following:
> >
> >
> > >
> > > We didn't realise that the water under these ice streams was moving in
> such large quantities and on such short time scales. We thought these
> changes took place over years and decades, but we are seeing large changes
> over months," says Helen Fricker at the University of California San
Diego's
> Scripps Institution of Oceanography in the US, who led the study.
> > >
> >
> >
> > Uh, oh. Most of the worry was concerning Greenland and it has been
> generally assumed that Antarctica would as it has in past deglaciations
lag
> the Northern Hemisphere. This appears to challenge that assumption.
> >
> >
> >
> >
> >
> >
> >
> >
>
>
>
> --
> David W. Opderbeck
> Web: http://www.davidopderbeck.com
> Blog: http://www.davidopderbeck.com/throughaglass.html
> MySpace (Music): http://www.myspace.com/davidbecke
>
>
>
>
> --
> David W. Opderbeck
> Web: http://www.davidopderbeck.com
> Blog: http://www.davidopderbeck.com/throughaglass.html
> MySpace (Music): http://www.myspace.com/davidbecke
>

-- 
David W. Opderbeck
Web:  http://www.davidopderbeck.com
Blog:  http://www.davidopderbeck.com/throughaglass.html
MySpace (Music):  http://www.myspace.com/davidbecke
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