On Dec 28, 10:22 am, Eric Swanson <[email protected]> wrote:
> I must strongly disagree with what you wrote.
>
> On Dec 27, 4:22 pm, Robbo <[email protected]> wrote:
>
> > Temperatures peaked (in every record of monthly temperature anomalies)
> > in the big El Nino of 1998. A wider significance of this is addressed
> > in the Tsonis et al and Swanson and Tsonis papers referenced - a
> > sudden climate shift in 1998/2001. Climate seen as a nonlinear
> > oscillator - a complex system in chaos theory. It seems possible that
> > the current cool mode will persist for another decade or two - until
> > the next multidecadal climate shift. New and startling science I know
> > - but as implacably logical as the Special Theory of
> > Relativity.
>
> There's another situation which may have impacted the climate of the
> late 1970's. It was called The Great Salinity Anomaly and was a large
> pool of relatively fresh water which circulated around the North
> Atlantic Sub Polar Gyre. About the same time, measurements indicated
> that the formation of bottom water in the Greenland Sea had ceased.
> That's like what may happen if the Thermohaline Circulation (THC) were
> to weaken or stop and most climate models coupled to dynamic ocean
> models predict that the THC will stop as the climate warms.
>
> http://www.whoi.edu/oceanus/viewArticle.do?id=2344&archives=true
>
You complain about Christy in 2003 - but use a 1996 (non peer
reviwed?) article on THC. If you had looked at the peer reviewed
science I referenced you would know that climate shifts - mini climate
tipping points - occur when global ocean states synchonise and then
shift into a different state.
THC is one of many nonlinear components of climate that has the
potential tobite us on the bum.
> One area in the Western Greenland Sea has exhibited changes associated
> with a reduction in THC in that area for the past two winters. The
> same pattern appears to be repeating so far this winter. Note the
> suggestion that the GSA was the result of increased flow of sea-ice
> out of the Arctic in 1967. That outflow has happened again these past
> few years. Only this time, it may not stop if the Arctic sea-ice
> melts away and opens the floodgates...
Short term characterisation of ocean elements that have obvious
decadal variability. THC in the Atlantic is one of those elements
that may result in an extreme nonlinear climate shift - morphing into
ice growth and an ice age over the next 10,000 years. Interesting -
but what do you want me to do about it? I already agree that we
should stop destabilising climate.
>
> > The current temperature trend is flat but any trend is masked by large
> > interannual variation mostly due to ENSO - making it impossible to be
> > definitive especially over shorter periods. Over longer periods of 50
> > or more years - the trend is about 0.1 degrees centigrade/decade.
> > Using the period of recent warming - 1976 to 1998 - includes two
> > periods of large climate fluctuation - the 1976/1977 'Great Pacific
> > Climate Shift' and the 1998/2001 climate shift - and distorts the true
> > rising trend. The other reference I cited was Thompson et al - who
> > filtered ENSO, volcanos and 'dynamically induced variability' from the
> > record. Reasonable estimates of the recent trend are about 0.1
> > degrees/decade.
>
> See above. The PDO may be associated with changes in the THC in the
> North Atlantic.
As above - the PDO and the IPO (Interdecadal Pacific Oscillation - a
Pacific wide phenomenon) - are probably an emergent global property of
climate as a dynamically variable complex system.
>
> > My post is a little disjointed - I started writing about scientific
> > uncertainty. But I think that greenhouse gas emissions need to be
> > reduced ASAP. The policy question is what the most effective way of
> > doing that is. My belief is that continued economic growth and the
> > technological path is the way to go. There are numbers of options for
> > power and transport. Cheap solar photovoltaic would be fantastic for
> > the developing world. Solar accumulators, high temperature nuclear
> > reactors, energy efficiency - literally dozens of emerging
> > technologies. Peak oil is a nonsense - there are many alternative
> > sources of carbon. Including coal gasification and liquefaction, tar
> > sands and shale oil - literally a thousand years of fuel supplies.
> > More exotic means of fuel production include high temperature
> > hydrolosis to create hydrogen which can then be combined with carbon
> > dioxide to produce liquid fuels.
>
> Peak Oil is a fact. Every oil field goes thru a period of growth then
> followed by decline requiring ever more effort to continue
> production. The sum of all the oil fields on Earth will also provide
> a similar production path. At some point in time, production or
> conventional oil will peak and begin to decline. Surely, there are
> other sources of hydrocarbons which can be used to make liquid fuels,
> but the Energy Return On Energy Invested (EROEI) for all these sources
> is less than that for the easy to get at oil we so carelessly burned.
> Tar Sands are a prime example, as natural gas is used to separate the
> dense tar from the mixture. There are no commercial operations which
> produce oil from oil shale, so we don't know how that might work out,
> but we do know the processes so far proposed use lots of energy. When
> the cheap energy is used up, the remaining fossil energy sources will
> become quite expensive to produce. That will make the products from
> that energy more expensive in dollar terms and that includes the
> renewables.
>
> Worse yet, the reserve data is subject to debate, witness the EIA's
> projections which look worse each year as the reality of the situation
> hits home. Sorry, the party is over.
Australians are building liquefaction plants for conversion of brown
coal to fuel. The cost of mining brown coal (it doesn't have a
commercial value) in the Latrobe Vally is a couple of bucks a tonne -
and I hasten to add - with sequestration of production CO2 in Bass
Strait oil fields. It is commercially feasible at US$70/bbl and with
a coal price of $20/tonne.
I read yesterday that the Canadians are looking at nuclear power for
fuel extraction from their huge coaltar sand deposits - oh horror.
It is really only an interim solution to part of the problem. Keeping
suppliers honest while real alternatives are developed.
>
> > It is interesting that Lomberg is wrong and a skeptic because - pretty
> > much as I do - he accepts that greenhouse gas emission reductions are
> > necessary. It shows that the issue is not scientific - science is a
> > threadbare justification for ever wilder claims of imminent doom. It
> > is economics and politics.
>
> The scientific part of AGW has just about been put to bed. Now, it;s
> a question for the politicians and the people to decide.
I think that there is a great deal of scientific uncertainty.
However, as I said, it hardly matters for sensible public policy. What
matters is the most efective way of reducing greenhouse gas
emmissioons. Bring it on.
>
> > 'Limits to growth' ideas are dangerous bullshit that put many lives
> > and legitimate human aspirations at risk. It matters a lot because we
> > have already seen food riots as a result of the misallocation of
> > global resources. But ecosocialism is not going to happen. Most of
> > the world want cheaper and more abundant fuels - and cars, washing
> > machines and air conditioners.
>
> Limits to growth is reality. We live on a finite planet and there's
> no obvious cheap energy source ready to replace the oil after the Peak
> is seen. I'm an engineer too and have studied solar and wind
> systems. They can be used to produce enough energy to keep things
> going, but not enough to allow everybody on the planet to live like
> the (formally) rich Americans who were able to waste oil and other
> energy sources with abandon. The suburban lifestyles we think is
> normal may pass away. Whether we find a rational path or return to
> the days of the tooth and claw with the meanest knuckle draggers
> running the show, only time will tell.
>
I have actually installed a solar voltaic system in my inlaws grass
hut on the Island of Misima. Bloody expensive way to run a few 12V
lamps, a DVD and a battery charger. A range of solutions is good - no
silver bullet. 4th generation nuclear - molten salt or pebble bed -
has to be an option for all of the cost, non-proliferation and waste
advantages it brings. Cheap power is all that is needed and
everything is possible including space colonisation for gods sake. If
you are an engineer - engineers (like Barack Obama) say yes we can.
I think the era of the meanest knuckle draggers was last century in
the operation of all of the socialist states. Dismantling democratic
and capititalist structures creates a power vacuumn in which scum
rises to the top. All of the best intentions of people from Shaw to
Einstein ending in the murder of hundreds of millions of people. To
me the rational path is economic growth and development and stable
democracies.
> E. S.
> ---
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