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IPCC - Climate Impact Risk set to Increase

#1 Guest_Chris Lloyd_*

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Posted 18 November 2011 - 13:10

A good article by the BBC on the IPCC's most recent report on climate change.

http://www.bbc.co.uk...onment-15745408

Make of it what you will.

#2 User is online   ldavidcooke 

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Posted 18 November 2011 - 16:02

Hey Chris,

What an opportune segway, given the point that the basis of the IPCCs conclusion appears to be false. The large body of the IPCCs conclusion is in part based on the 2005 work of Dr. Kerry Emmanuel and Dr. Judith Curry.

The 2005 Emmanuel et al, primarily reviewed satellite images of hurricane cloud tops to obtain estimated wind speeds. Though the observations were correct as was an apparent trend the conclusions were likely wrong. It was clear that the greatest influence in the warming conditions were more likely due to the long duration of a El Nino condition during the period being evaluated. When this was pointed out to Dr. Curry, she appeared to reconsider her pov.

The problem was that the counter paper generated by Dr. Landsea and later by Dr. Chang did not have enough evidential support and sought to challenge Dr. Emmanuel's conclusion due to the changes in the observation technique. Now 6 years later we can see that a large portion of his position is bring supported by the evidence stream, at least in the Atlantic. The problem is it will require a new paper to challenge the original work.

At issue with a more recent paper will be that most of the observations will be dominated by a La Nina. Hence, drawing a conclusion based on the same evidence stream is as error prone as the prior effort. The real issue is how to examine the evidence in light of measurable changes and one that extends past the satellite era.

The best bet for this effort will likely be to use SSTs. The basis of the Dr. Emmanuel work was that the increase in solar surface heat gain would result in an increase in ocean heat content. It would be from this well that the convective plume would grow and become impervious to shear forces. In truth, the ocean heat content does not increase much. The surface area at or above 82F/28C has increased as has the surface salinity. Both of these conditions are clear indications that the additional heat is more likely to go into water vapor then the ocean.

Hence, increases in SSTs should result in, more storms as the season would expand to take advantage of the longer duration SSTs at or above 28C. Next, due to the increase in covered area, there should be a two fold condition, one is that there should be an increase in sub-tropic storm development and two an increase in concurrent storm development. Both of which would likely reduce storm intensities as they would weaken any surrounding Anti-Cyclonic Dryline feeder bands.

As to confusing these patterns with the effects of the ENSO phase, if nothing else, the trending of the SSTs has been constant over time. The biggest changes we have seen over the past 30 years has been not only the SST and SSS values; but, also the cross zonal flow of the Polar Jet Stream.

It is more likely that the change in the Jet Stream flow is being driven by the increases in both specific humidity and atmospheric heat content. With most of the water vapor cycle being a closed system and the heat content being a open system the combination have changed the atmospheric heat flow resulting in more heat content in the Polar and Equatorial Jet Streams invoking greater zonal variation.

It is the change in the heat flow that we appear to be seeing resulting in greater shear forces, both reducing land crossing and development of TCs into impervious warm core systems. It is this change that seemed to follow the 2004 and 2005 TC seasons that appeared to create the, "2006- The year without a land-crossing Hurricane".
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#3 Guest_Chris Lloyd_*

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Posted 18 November 2011 - 19:47

Thank you for the reply Dave. The IPCC report was discussed on the news this evening. A chap (name escapes me now) from the University of East Anglia pointed out that it is very difficult to attribute the effects of human emissions to specific extreme events that occur around the world. References to a 66 percent probability that these events should occur is by no means compelling evidence.

#4 User is online   ldavidcooke 

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Posted 18 November 2011 - 21:17

Hey Chris,

Mainly as long as most WX events occur within 1 standard deviation and the median over the years has changed so little, the chance any one activity may be responsible may be small or an even chance it was not responsible (50/50). However, where an extreme event exceeds a prior maximum range value it suggests that the maximum possible influence of human activity could be equal to the amount the range has been exceeded. When you have no less then 10 official degrees of freedom which can drive the possible extreme it is likely that human activities can be the sole source; but, as to whch activity is primarily responsible it is very hard to say.)

However, as to the influence in the extreme it can be said with a high degree of certanity that human activity could have responsibility for the extreme measured for the time period the value has been measured. Meaning, the possibility that fossil fuel emissions are responsible for the Moscow Heatwave is little more then 10%. But, the probahility that the Moscow heatwave occurred due to human activity is likely greater then 97%. If we can ever get to the point that we can measure the amount of influence human activity alone has on extremes, it s very likely that the science defining the influence of the 10 possible degrees will be fairly accurate.

For instance if you wanted to suggest the potential human influence in the conditions that caused the Moscow Heatwave. You could take note of all the values whch exceeded 1 standard devation based on the annual median value for say the last 130 years. If you graph those values you will get a near step up pattern with a period near to 60 years. If you remove the trend and then instead simply create a dot plot where the center point is the median value of the range and the dot is the degrees above the median for each observation, you should get a nice one sided bell curve. The end result is the outliers are the extremes of the extreme highs, the amount of dots containing up to 67% of the data points are your normal variation, the values between 67-97% of your dots are those events likely driven by multiple influences, you will be able to tell because there will be some values showing a bunching or multiple peaks within the tail. Then at the end you will have few and scattered values these values are likely human driven. They will not bunch up as the influences will rarely be a repeat these represent a combination of natural variation and human activity. If you remove the value for the natural influences these values will likely point to how much humans add to natural varibility.

If you wish you could probably apply the IPCCs 10 degrees of freedom values and confirm that the value that would result matches up with the local or regional trend in the average temperature. (IE: If you remove the trend and variation from the Moscow temperature extreme we see a balance of nearly 3 deg C. If we apply the AR4 percentages roughly 30% of the estimated value or 0.9degC can be attributed to fossil fuel emissions. This comes dramatically close to the estimated value of 0.85C trended average increase suggested for this region.)

Ifwe had come to this conclusion independent of any knowledge of the best science had to offer it could be believable. What worries me is when we already have scientific knowledge how much does this influence our results or modeling constructs? That there is an underlying 1 degC rise through out the record that cannot be explained I find concerning, it is not rebound based, nor can it be attributed to emergence from the ice age. I know it is not a UHI factor because it is too high. It is not fossil fuels as emissions did not achieve critical levels until nearly 60 years after the record started.
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#5 User is offline   John Mason 

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Posted 18 November 2011 - 21:23

Hey Dave,

That last sentence - would you clarify what you mean by it please? - e.g. what are "critical" levels and why?

Cheers - John
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#6 User is online   ldavidcooke 

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Posted 18 November 2011 - 21:40

Hey John,

It is a combination of factors, prior to the 1950s, most heating, in the Eastern European region, would have been peat based meaning little contribution in this instance was due to coal. As most forest were the domain of nobility little if any generation by individuals or small businesses could have contributed much. It was not until standing timber was struck, and the resulting fields tilled to support the growing population that humans had much influence in weather patterns. However, post the 1920s, when the advanced demand for energy began to affect the global emissions and the natural sequestration could no longer absorb the emissions, that the condition turned critical. Not unlike the current economic issues, as long as payments could be banked to meet the demand for credit everything was fine. Once a payment was missed or threatened... Hence, once human activities reduced land sequestration of CO2 and the ocean surfaces began to warm reducing the uptake even more the system was over drawn.

As long as we can return the atmospheric system to a carbon negative environment things should improve it just means we have to either emit less or uptake more. Currently sitting on our hands does little. As an aside, I have little problem with fossil fuels if the fossil fuel consumers would implement carbon sequestration either in their processes or set up a business to balance off their emissions... Does that help?
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#7 User is offline   John Mason 

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Posted 18 November 2011 - 21:59

Yes Dave, but I'd take odds with your contention that most heating prior to the 1950s was peat-based.

I'd be more inclined to look to the start of the Industrial Revolution as the point at which the escalator was started - though I'd need to get hard data to quantify that. But Europe was certainly burning huge amounts of coal annually by the 19th Century and - OK it's one tiny sample of Europe - the very extensive woodlands had been decimated before then, because of the demand for fuel to smelt the metal-ores that were mined in the country. I wonder if you are viewing the world through American eyepieces, while I'm doing the same through European ones!!??

Agree though - fossil fuels could become carbon-neutral. There would need to be a reduction in usage, sure, but that can be achieved via innovation that leads to far greater efficiency, innovation that leads to alternatives becoming mainstream and behavioral change to less wasteful practices. All of these are do-able: the technology is there, but will the behavior change? It'll have to one day, and it doesn't matter if supplies of coal or shale-gas peak in 100 or 500 years: the bottom line is that the economically-recoverable fossil fuels will run out one day, and the longer lead-in to that point in History we have, the better!

Elsewhere on the internet, I see a firestorm is ongoing on this topic, but these days that is not that unusual. These are strange days indeed......

Cheers - John
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#8 User is online   ldavidcooke 

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Posted 18 November 2011 - 22:48

Hey John,

Up through the 1870s most transportation systems such as steam engines primarily were wood burning, except for the co-dependent relationship which developed between France and Germany. The greatest transportation consumers of coal in the late 1800s were ships as they required the most efficent energy possible with the minimum bulk possible. Most heating systems were wood based here in the States, until large urban areas sprung up around new immigrants, requiring the minimum of bulk and the highest efficiency possible. Wood was simply more economic... Later the move to coal oil or gas which could be piped instead of trucked in became more cost efficient.

The biggest demand was as you said, for smelting. Most textile mills in the North were powered by the same systems that powered the grain mills. It was not until the expansion of lumber mills requirng processing where there was little fast moving water that the demand for steam was required; however, most ran off of their scrap. As to Europe it was the introduction of personal property allowing the ability to harvest forests to the point that coal would be required to meet heating demands outside of the Steel mills and large cities.

Though the total tonnage may have been high, in the latter half of the 19th century, it was a pittence compared to what the environment could process... at least up till the forests were converted to farmlands. As to the East European needs, much was powered with wood or peat. Matter of fact, one of Moscow's main siteing benefits was the neighboring peat bogs...
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