http://tinyurl.com/gubph

You will also notice at the bottom of this they refer to their model outputs as “data.”

http://tinyurl.com/hj7uq

Freudian slips? Clearly they think they have eliminated all potential uncertainty. It would be nice to have that crystal ball…

Although there are cherry-picked anecdotal studies in either vibrant and robust, or on the other end nutrient poor conditions, competent studies indicate that there will be some increase in arable land with an increase in CO2. Balance that against the the fact the magnitude of the CO2 component to increased warming is highly uncertain. The question is: should we be looking to limit CO2 emissions at all?

We just don’t know, and the risk that just eliminating that food enhancement could be devastating to a large part of the world’s population means the Precautionary Principle really says don’t waste money throttling back productivity, instead spend money realistically researching climate components and fine tuning models.

The key word here, of course, is “realistically.”

“The value lies in isolating and defining at least one element of uncertainty. That allows policymakers a view into potential effects of their actions.”

That’s a nice theory, but the fact of the matter is that ALL the scenarios in the IPCC Third Assessment Report are based on no government intervention (at least specifically for climate change).

So policymakers are told that, without government intervention:

“The globally averaged surface temperature is projected to increase by 1.4 to 5.8°C (Figure 5d) over the period 1990 to 2100″…

…but the IPCC Third Assessment Report doesn’t say whether the warming is likely to be in the lower part of that range (or even BELOW that range) or in the upper part of that range.

Could someone recover my comments/questions to Hugh? No need to recover my request for recovery…when I also forgot to sign in.

Thanks!

I had comments to Hugh that I just sent. It’s taken me a while to finish them. I swear I was signed in when I started them. But now I’m not. Again, I forgot to cut/paste them to my email. (I probably should just do everything by my email.)

Could someone retrieve them? Sorry!

Thanks,
Mark

You write, “Okay, I’m biting my lip here a bit because I seem to be walking headlong into one of your booby traps…”

One of my “booby traps?”

???

“Any device or material which is designed, constructed or adapted to kill or injure and which functions unexpectedly when a person or object (vehicle) disturbs or approaches an apparently harmless object or performs an apparently safe act.”

Geez! I think I have a bit more sense of perspective than to use those!

Anyway, your opinion is that the statement, “The globally averaged surface temperature is projected to increase by 1.4 to 5.8°C (Figure 5d) over the period 1990 to 2100″…is a “projection” rather than a “prediction.”

I guess I shouldn’t even have asked, because I’m still confused. I apologize, I have more questions:

1) Since that statement is a “projection” rather than a “prediction,” is it falsifiable? That is, is there any future that renders the “projection” false?

2) The temperature “projection” of 1.4 to 5.8 degrees Celsius is presumably based on supporting “projections,” e.g., methane atmospheric concentrations and CO2 emissions and atmospheric concentrations. For example, if I go to Figure 5 of the IPCC TAR, I see these “projections” for CO2 emissions and atmospheric concentrations:

http://www.grida.no/climate/ipcc_tar/wg1/figspm-5.htm

Are there any future events which can falsify those “projections” (i.e., show them to be wrong)?

3) Of what possible use for policy making is a “projection” of 1.4 to 5.8 degrees Celsius temperature rise? Don’t you think it makes a big difference, from a policy standpoint, if the warming is 1.4 degrees Celsius vs 5.8 degrees Celsius?

4) Suppose I told you (and I do! ) that I predict there is approximately 50% probability that warming in the lower troposphere from 1990 to 2100 will be less than 1.4 degrees Celsius. In your opinion, is my “prediction” compatible or incompatible with the IPCC TAR “projection?”

Best wishes,
Mark

One way to look at it is to say that a prediction is unconditional, such as “x will happen”, whereas a projection is 2 or more conditional predictions: “if a, then x will happen; if b, then y will happen”.

The value lies in isolating and defining at least one element of uncertainty. That allows policymakers a view into potential effects of their actions.

Roger – thanks for posting the direct link to the McCracken paper. I think it is useful. I also saw the link to your projection book, and the chapter headings that are available online make it look quite pertinent. But I’m not sure why you say that the prediction/projection distinction is meaningless in the case of climate science. If you mean that the distinction is lost on people, then we must educate.

Certainly the names of the government agencies don’t help. At DOE “Climate Change Prediction Program” is unfortunately presumptuous and misleading at best. Then the “Accelerated Climate Prediction Initiative” within that group again says “Prediction”. Unfortunate.

Steve H – if your parameters of albedo, transpiration, and solar forcing turn out to be controlling, time will tell. But it’s worth a look at IPCC TAR and following research to see why that’s not looking likely.

Okay, I’m biting my lip here a bit because I seem to be walking headlong into one of your booby traps…but…

In my (very) humble opinion the statement:

“The globally averaged surface temperature is projected to increase by 1.4 to 5.8°C (Figure 5d) over the period 1990 to 2100.”

Means that, dependent on the emissions scenario applied, global…blah blah..will rise to a point where the mean temperature will end up at a point somewhere within the range of 1.4-5.8°C. i.e. a low emissions scenario will result in mean temp being in the bottom end of the range and a high emissions scenario will result in the mean being in the upper end.
This makes these *projections*

A *prediction*, again IMHO, would require the analysis of current global energy policies (to identify current and planned levels of capital expenditure on emitting /non-emitting power sources), and various business plans/trends (e.g. automobile manufacturers) to assess how such businesses’ emissions are being planned to increase decrease in the future.

I understand the issue about the investigation of such plans stepping across the divide into *projections* but major infrastructure (e.g. a power plant)does have a design lifetime and I therefore suggest that *predictions* can at least be guided up until the end of this period.

As I read it *projections* are there to *guide* energy policy i.e. if we rely on coal-fired energy production the global temp is going to be toward 5.8°C.

Projections therefore indicate choices

Where am I going wrong????

Also, his discussion of strictly albedo changes of land use changes without considering the effects on transpiration is interesting. How valuable is an assessment of -0.02 deg per century based on land use changes without considering transpiration? I suggest it is wholly irrelevant to the big picture.

While he touches on the differences between forcings and feedbacks, his analysis has a strictly anthrocentric view, dismissing the fact that CO2 follows temperature.

The possibility that land use changes from our current burgeoning population (not to mention black carbon) are decreasing transpiration leading to decreased cloudiness is outside his paradigm, therefore beyond his comprehension.

Then again, this is an old paper. 4 years is a long time in climate science – although not so long considering the entrenchment from the inbreeding, strengthening the alarmists’ credo.

Many thanks for recovering my comments to Hugh Deeming.

Best wishes,
Mark