Sea Level Rise Mapper
Robert A. Rohde
recently created a new tool of hopefully broad utility (and frankly a
bit of fun) that I think people here may have an interest in.
Specifically, I created a Google Maps application that allows one to
explore in detail which regions of the Earth are most vulnerable to
sea level rise.
http://www.globalwarmingart.com/sealevel
As with other Google Maps you can zoom out to identify low lying areas
globally, or zoom way in to focus on a particular part of a particular
city.
Enjoy.
-Robert A. Rohde
http://www.globalwarmingart.com/
David
As for the coming sea level rise, my personal belief
is that Al Gore vastly overestimates it.
I would be greatly interested for NGers to chime in
with their estimates of how concerned the public
should be for what beach erosion etc. will occur.
BTW, we might form a consensus for the coming centuries
on such primary climate factors as increases in
solar radiation and/or changes in the earth's orbit
and/or changes in the earth's cloud cover.
David Christainsen
Michael Tobis
unless CO2 concentrations are actually made to retreat. The only
question is the time scale. Since Gore did not specify the time scale,
he is strictly speaking correct.
On the other hand, the viewer of AIT was left with the impression that
such rises were imminent. This is fair grounds for criticism of the
presentation, and indeed it was the first thing that left my lips on
leaving the movie. That is not generally considered likely. There are
outliers though, notably James Hansen who believes several meters in
the current century under business-as-usual is to be expected.
If you listen to what Gore says in detail, he merely says it is
plausible. That is a defensible position. However, people respond to
symbols rather than words. It may be argued that the constraints on
what Gore says are distinct from those on what a scientist should say.
See
http://pubs.acs.org/subscribe/journals/esthag/41/i21/html/110107viewpoint_fischhoff.html
A decade ago we believed that ice sheets retreat mostly by melting.
This turns out to be false; land ice can simply fall into the ocean by
mechanical processes with weakened ice. So recently the trend among
informed opinion has been to greatly increased concern about this.
The likely mechanism for retreat of the WAIS in particular is not
well-constrained as to time scale. Several meters in the present
century is outside the consensus expectation but within the realm of
plausibility.
mt
Zeke Hausfather
massive sea level rise this century. I wrote a piece on this subject
at the Forum a few weeks back: http://yaleclimatemediaforum.org/dept/0208_sealevelrise.htm
If I had to bet, I'd predict a range of 0.5 to 2 meters this century
given uncertainties in dynamic ice sheet processes. That said, we
really know very little at this point regarding how significant ice
sheet dynamics will be. While we can't rule out Hansen's top end
projections at the moment, there also seems to be no need to stress
them. Instead, we should stress the uncertainties involved at the
moment and encourage more research.
Michael Tobis
mt
David
> There is little doubt that the WAIS and Greenland will melt eventually
For the next century my estimate of sea level rise
is about a foot.
In this scenario not all of the rise is due to global
warming; other factors include calving and ocean current
dynamics.
IOW, no runaway, no Venus, no massive change in
the patterns of agriculture.
Do others agree?
jdannan
> There is little doubt that the WAIS and Greenland will melt eventually
> unless CO2 concentrations are actually made to retreat.
I'm not sure how you mean this to be parsed. It is certainly doubtful
that these ice sheets will substantially melt at a CO2 concentration of
~380ppm. I would accept that is likely that they would melt were the CO2
concentration to kept above 550ppm for an indefinite period, but I'm not
sure even that would leave "little doubt". OTOH maybe your comment is
based on the (reasonable) belief that we will blow past 550ppm and far
beyond anyway.
James
Michael Tobis
already in the Amundsen embayment, and that a sustained 380 ppmv would
suffice. I indeed went as far as "little doubt" on the strength of the
likelihood that we are very unlikely to see 380 as the peak.
The exact threshholds are probably not knowable in advance, but it is
worth noting that these did fail entirely in the previous
interglacial, so we presumably started off quite close to that point.
mt
Steve Bloom
forcings? One thing I've been wondering about since seeing the recent
Rohling et al paper (discussing SLR rates at the end of the Eemian melt) is
the differing character of present vs. Eemian forcing. Eemian Co2 levels
were only ~300 ppm, but increased high-lat insolation changes resulted in ~5
meters additional SLR. This *seems* like it should imply important
differences in the melting. Among other things, would the warming currents
from lower latitudes that appear to be a critical factor at both poles in
the present warming have been as significant in the Eemian? What about the
differing seasonality of forcing from CO2 vs. insolation? I'm sure it's a
longer list, but that's a start. I'm also sure that somebody must have
looked at this, but a few minutes googling turns up nothing.
-- Steve Bloom
Tom Adams
>
> - Show quoted text -
I'm just a layman, but after a good bit a reading, I have the
impression that the risk of drought should get relatively more
attention. It's shorter term concern, I think, for the USA at least.
Partly due to the fact that a good chunk of the USA is already
teetering on the brink of drought.
The IPCC reports do seem to have this problem with having to leave out
various factors in sea level rise that cannot currently be
quantified. Leave them out of sea level rise estimates.