A very cogent comment on 'planetary boundaries'

[raja]

Re: A very cogent comment on 'planetary boundaries'

Can you point me to one of these articles?

Ice core data in particular is very problematic with regards to a time scale as fine as 1 decade. Snow has to fall, get compressed, then turn to ice.

This seems to suggest that decade-long data can be assessed:
http://www.washington.edu/news/2013/...und-of-normal/

The researchers’ results are based on their analysis of a new ice core from the West Antarctic Ice Sheet Divide that goes back 2,000 years, along with a number of other ice core records going back about 200 years. They found that during that time there were several decades that exhibited similar climate patterns as the 1990s.

[Polish_Silver]

About exponentials

"The extinction of the human race will come from its inability to EMOTIONALLY comprehend the exponential function."

- usually attributed to Edward Teller, but more likely from Albert A. Bartlett

It should also be remembered that exponential trends do not usually last very long.
They encounter some sort of limiting factor.

One of the most impressive impressive exponential relationships I know of occurs in bipolar transistors. The collector current is exponentially dependent on the base-emitter voltage, and this relationship can extend from 1x10^-9A to 1x10^-3A, a range of about 6 powers of 10.

However, bipolar transistors are not a danger to the human race.

[c1ue]

Re: About exponentials

This seems to suggest that decade-long data can be assessed:
http://www.washington.edu/news/2013/...und-of-normal/

Steig - the author of the report noted above - has very little credibility in my book.

He's the one who tried to show Antarctica was warming by including defunct stations as well as heavily weighing the 2 (out of dozens) of stations which would support his thesis. That paper was crushed when it finally exited its (pal)peer review and was published.

If Steig is saying ice cores can show decade level sensitivity, I'd pretty much automatically assume it is a lie.

If you're interested in what Steig attempted to do (and which was debunked), see this link:

http://wattsupwiththat.com/2009/02/2...tic-heartburn/

[Polish_Silver]

I love Steig??

Steig - the author of the report noted above - has very little credibility in my book.

He's the one who tried to show Antarctica was warming by including defunct stations as well as heavily weighing the 2 (out of dozens) of stations which would support his thesis. That paper was crushed when it finally exited its (pal)peer review and was published.

If Steig is saying ice cores can show decade level sensitivity, I'd pretty much automatically assume it is a lie.

If you're interested in what Steig attempted to do (and which was debunked), see this link:

http://wattsupwiththat.com/2009/02/2...tic-heartburn/

C1,

You are so on top of the literature somebody should pay you for it!

But the recent Steig reference was claiming something you might agree with, that
AA warming and ice melting on a par with 1990 had ocured several times in the last few centuries, just not on the peninsula.

Why we obsess so much over the peninsula, I'll never know.

[c1ue]

Re: I love Steig??

But the recent Steig reference was claiming something you might agree with, that AA warming and ice melting on a par with 1990 had ocured several times in the last few centuries, just not on the peninsula.

The article above does carefully note a couple of times that Steig's work applies only to the Antarctic Peninsula, and the more recent work involves the West Antarctic ice sheet.

However, the fundamental problem is the extrapolation. There are any number of assumptions underlying the ability to say that:

If we could look back at this region of Antarctica in the 1940s and 1830s, we would find that the regional climate would look a lot like it does today, and I think we also would find the glaciers retreating much as they are today

This may be true, but it is far from clear that it is given the very short time scale of modern data vs. the period of time being extrapolated to.