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healyje
Trad climber
Portland, Oregon
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Oct 23, 2012 - 05:58am PT
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One such thing is the boundary of the possible trajectories, and how that boundary depends on physical parameters.
This is an important distinction since it may not be important to be able to accurately predict weather to be able to accurately predict climate.
Both pretty spot on with regard to modeling...
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Chiloe
Trad climber
Lee, NH
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Oct 23, 2012 - 09:53am PT
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Ed's reference to the North Atlantic cod collapse seems relevant to this thread in another respect as well. Although cod populations were depleted by sustained overfishing, the final collapse of Greenland and Newfoundland stocks coincided with and was deepened by adverse climate/oceanographic conditions. Emphasis added below:
Northwest Atlantic cod illustrate the negative synergy of environmental adversity coming atop overfishing. West Greenland stocks (first graph in Fig. 2) were reduced by peak overfishing in the early to mid-1960s. The fall after this peak coincided with the abrupt arrival in 1969–1970 of a pulse of cold, fresh Arctic water (see Fig. 1). Although warmer conditions eventually returned to West Greenland, they were punctuated by further episodes related to circulation changes and Greenland ice-sheet attrition (Belkin et al., 1998; Belkin, 2000) that created conditions off West Greenland periodically too cold for local spawning. Moreover, wind and North Atlantic Oscillation (NAO) related shifts in flow of the Irminger Current resulted in fewer cod being imported from Icelandic waters (Buch, 2000; Buch et al., 2003). After a small terminal spike in fishing between 1988 and 1990 (mainly exploiting a 1984 cohort arriving from Iceland), Atlantic cod virtually disappeared from West Greenland. Several other demersal species had declined steeply as well (Ratz, 1992, 1999). After cod declined, northern shrimp (Pandulus borealis) became more abundant, a trophic-level shift consistent with Pauly et al.’s (1998) description of “fishing down food webs.” An emerging shrimp fishery took the place of cod as Greenland’s economic staple (Hamilton et al., 2000, 2003; Rasmussen and Hamilton, 2001).
The 1990s collapse of Newfoundland’s cod fishery (second, third and a share of the fourth graph in Fig. 2) followed a similar pattern of overfishing compounded by adverse climate, near-disappearance of the dominant species, then a new ecological and economic prominence for crustaceans. Biological analyses point to overfishing, first by international fleets in the postwar years, then after 1977 mainly by Canadian vessels, as the primary cause of the cod collapse (Hutchings and Myers, 1995; Sinclair and Murawski, 1997). Cod stocks eroded to historically low levels in the mid-1970s, and made no more than a partial recovery before the Canadian effort ramped up. Climate added to the resumed fisheries pressure in the late 1980s and early 1990s, when unusually cold, icy waters off east, north and northwest Newfoundland (Drinkwater, 2002) reflected some of the same NAO/circulation anomalies that beset the final years of Greenland’s cod fishery. Cod abundance, size-at-age and catches all began falling after the mid-1980s peak in catches that Palmer and Sinclair’s (1997) northwest Newfoundland fishermen described as their “glory years.”
 Hamilton (2007)
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dirtbag
climber
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Oct 23, 2012 - 10:49am PT
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I do not understand MODERN science
So Chief Running Mouth, if you don't understand it why don't you do everyone a favor--especially yourself--and shut your fat IGNORANT mouth?
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raymond phule
climber
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Oct 23, 2012 - 11:00am PT
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The very recent peer rev'd ref I posted regarding the North Atlantic COD fisheries, SUPERCEDES your personal non-peer reviewed OPED!
OPED? It looks like a published conference paper to me.
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Chiloe
Trad climber
Lee, NH
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Oct 23, 2012 - 11:01am PT
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SUPERCEDES your personal non-peer reviewed OPED!
Not a reading man, are you chief?
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Chiloe
Trad climber
Lee, NH
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Oct 23, 2012 - 11:05am PT
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That is a peer-reviewed paper published in the oceanography journal Deep Sea Research II. The papers it cites have been peer reviewed too.
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dirtbag
climber
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Oct 23, 2012 - 11:12am PT
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Nah... I believe I will stay awhile so maybe I can... understand your bullshet junk science.
Then try LISTENING for a change.
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raymond phule
climber
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Oct 23, 2012 - 11:25am PT
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Sure is but it AINT peer reved as all you warmist dictate a valid pub'd paper should be.
Why do you just make up stuff? Is that the military way to discuss?
You say it is a OPED when it is not a OPED. You say that it is not per reviewed when you didn't know if it was per reviewed or not.
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Chiloe
Trad climber
Lee, NH
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Oct 23, 2012 - 12:01pm PT
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Negative.... clarifying who and what.
Bullsh#t. You did not ask, or make any attempt to clarify.
your personal non-peer reviewed OPED!
and
it AINT peer reved as all you warmist dictate a valid pub'd paper should be.
A more honest man might have noticed the source, Deep Sea Research II, or taken 15 seconds to look it up if he wanted to "clarify."
A smarter man might have read what was in the passage I quoted, and recognized that it does not resemble an op-ed in any way whatsoever.
What percent of the 38.95 do you get btw???
Zero.
LARRY
Hey chief, I have a proposal for you, since you're so devoted to attacking people by name. How about signing your own name, Rick Poedtke isn't it, each and every time you feel that need to personally attack somebody else using their name.
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213
climber
Where the Froude number often >> 1
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Oct 23, 2012 - 01:11pm PT
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Cool, thanks for the great reply Ed! As you probably can tell, my 'trolling' is done in an attempt to elicit useful knowledge for the masses (or just for myself haha). Gotta take advantage of learning from those who have been in science for a while! I've studied a bit of deterministic chaos on my own (check out 'Determinisitic non-periodic flow' by Lorenz for some mindboggling stuff), but will be diving in deeper with Strogatz's fine text after I finish working through Mary Boas' book and honing my mathematical methods to a sufficient level. So much to learn, so little time!
If the terrestrial, atmosphere, ocean, biosphere system is such a dynamical system, then no matter how powerful our computer models are, we cannot predict the evolution of this system in time in principle.
Well said. The observational or measurement problem of the initial conditions is huge. Some other keys to understanding the problems with such modeling efforts lie in how the equations of motion are solved. The Navier-STokes have so far, no analytic solution, thus they must be solved numerically. This brings up the fun and games of rounding errors (since computers can only store a finite number of digits) and truncation errors (we cannot calculate infinite sums for each equation/gridpoint etc such as in a Taylor approximation, thus our answer is limited to some degree of error). Now we are in trouble, for the true evolution of the system will diverge from our numerical representation (forecast) as the errors grow. Some go as far as to argue that we lose the real physics of the system with certain numerical approaches.
The bridge between weather and climate is highlighted by this issue. Weather is the transient (day-to-day) phenomena whereas climate is a time-averaged mean state.
This is an important distinction since it may not be important to be able to accurately predict weather to be able to accurately predict climate.
The problem with this view, is that of the 'energy cascade'. How does energy flow, or cascade both up and downscale? If nothing else, running crazy high spatial resolution (1-10km**2 resolution) shows just how important energy transfer from small space and time scales is between atmospheric scales of motion. The climate models are unable to capture/represent fine scale phenomena such as convective clouds, heat fluxes from air-sea interactions, and other very important features relevant to forcing local and regional weather but also impacting the longer term atmospheric state (climate on the 'quick' end). The features which cannot be captured must be parameterized. In doing so, we lose the true evolution of the system. The worse our parameterizations (or observations) are, the further the model drifts from reality as time goes on. We miss capturing the energy cascade, therefore we don't get all of the key features necessary to develop a realistic model scenario. When this is done for a long run, or integration period, our modeled system drifts and we lose the grasp of 'is this really how the system will respond?'
The long-term weather/short-term climate forecasting problem has many of the climate secrets hidden within it. This, I think, is perhaps the most fruitful area of research that should be far more well funded than it is. Millions of dollars to develop downscaled projections (sorry LLNL people) or the same amount to develop improved physical understanding of how ENSO develops? I know where my pen will sign...
In my opinion, we will learn far more about the coupled Earth system by learning more about the dynamics and trying to understand how the energy relationships and exchanges occur at small space and time scales than we will spending mad money merely running GCMs with all the 'switches' in different places and different values for pCO2.
The answers are in the clouds!
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213
climber
Where the Froude number often >> 1
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Oct 23, 2012 - 01:50pm PT
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Example of 'weather' driving 'climate extremes' from my research:
Planetary wave breaking (largest scale) kicks off a synoptic scale polar outbreak of cold Siberian air.
Intensive mesoscale air-sea interaction of the cold air and warm Kuroshio current drives mesoscale convection which helps to develop a large height gradient environment that in turn accelerates the merged polar and subtropical jetstreams from a synoptic scale to planetary scale phenomenon. Significant weather impacts observed on the North American west coast and hemispheric wave reorganization occurs for nearly three weeks after. A GCM at 50km^2 resolution will capture the general picture, but will miss out accurately capturing the mesoscale processes that make these events so interesting. Our model outer domain was 60km^2 but we had a 10km^2 inner domain centered over the Kuroshio region. Major differences were observed in heat fluxes between the model and the buoy observations (the model greatly underestimated the fluxes).
So, we have the energy cascade: downscale, upscale, downscale.
Weather does matter with regards to climate, it is misleading to say that we can get long term climate predictions without being able to forecast weather features well. The small stuff matters, and if we miss it, we miss a chunk of the big picture.
Significant precipitation events (read floods, major snowfalls) are often linked to similar conditions as are shown.
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healyje
Trad climber
Portland, Oregon
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Oct 23, 2012 - 02:00pm PT
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Dr. F: The genetically modified plants have been modified by laboratory insertion of specific DNA sequences that code for favorable attributes. Like resistance to Roundup, etc.
Normal breeding techniques just select for desirable attributes by breeding select clones together.
I would probably tend to clarify this statement by saying "modified by laboratory insertion of specific DNA sequences which could never be selected for traditionally or are sourced from another species"
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213
climber
Where the Froude number often >> 1
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Oct 23, 2012 - 02:05pm PT
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Healyje +1
If you can't select for the trait via breeding and must utilize modern techniques to insert genetic material into the host genome, that is where the difference appears to be between genetic engineering and breeding. But I am no biologist!
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healyje
Trad climber
Portland, Oregon
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Oct 23, 2012 - 02:21pm PT
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The bolts are already spaced close enough without breeding shorter climbers.
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healyje
Trad climber
Portland, Oregon
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Oct 23, 2012 - 05:27pm PT
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Viral insertional mutagenesis, like transposon mutagenesis and bacterial conjugation ('gene swapping'), is certainly a significant factor in evolution, but to equate that to what we are doing the lab is a stretch at best. Both are certainly natural processes, but are not open to human manipulation by traditional breeding practices other than indirectly and incidentally.
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Chiloe
Trad climber
Lee, NH
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Oct 23, 2012 - 08:24pm PT
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without any higher education
I know dull people with degrees and sharp people without them, so there's more than that to it.
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Lennox
climber
just southwest of the center of the universe
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Oct 23, 2012 - 08:31pm PT
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Are those breasts??? Perhaps he suffers from 'roid-rage?
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rottingjohnny
Sport climber
mammoth lakes ca
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Oct 23, 2012 - 09:20pm PT
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Rick...Question..? In the first picture you seem to be suppressing something....? Were you thinking about Lance Armstrong or the nice looking lady in powder blue to your left....? RJ
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BASE104
Social climber
An Oil Field
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Oct 23, 2012 - 09:20pm PT
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Frontline is airing a show about the politics which surround climate science at 9:00pm central time.
Not sure the time on the west coast. Channel is PBS.
Frontline is probably the only investigave jounalism left on TV. Should be interesting.
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rottingjohnny
Sport climber
mammoth lakes ca
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Oct 23, 2012 - 09:31pm PT
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Rick...I like sheep also and can relate...RJ
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