Arctic ice melting faster than predicted!

While you're there, given that you've already made a long trip from home, I'd suggest you venture a little further North to see Mount Robson, Banff, and Jasper. The glaciers might last a little longer, but you never know.

 

And let's add Alaska as a destination where the glaciers are also melting. We had a fabulous glacier cruise there in 2009. But I was mystified when the ship captain said, during his speech, that they (Alaska) were not sure if the global warming was man-made or not.

Re: Mountain, glacier ice melting, isn't there some thought that this is also caused by particulates, aside from the +CO2 issues?

 

I believe there is. I read an article on Green Car Congress a while back that discussed this issue at length. the main thrust of it was that we should tackle soot because it's problematic, but has a very short residence in the atmosphere, so massively cutting soot emissions will have an effect in short order.

 

Amazon tree growth rates. I have much interest in this topic. The “slow growth†paper mentioned, I suppose, is Vieira et al. 2005. They used carbon-14, a rather new, expensive and whiz-bang technique (wish I could afford it…). They compared that to repeated (conventional) diameter measurements of tagged stems and found good agreement. They found that smaller trees in the understory grew surprisingly slowly, and were surprisingly old. Big trees (canopy emergents) grew fast and at more-or-less expected rates.

That study was done that 3 lowland Amazonian sites, and trees there do produce growth rings (higher-density wood) because of slower growth during the dry season. But the rings are not always interpretable, especially for those (light-suppressed) understory trees.

There are many other studies done elsewhere in Amazonia, with tree growth measured by diameter re-measurement of tagged stems over time. AFAIK those do not show especially slow growth.

Frankly, I’m not quite sure what to make of the “impact of rainforest on CO2 balance was overestimated by something like x10-x100 timesâ€, so I’d need more help with that.

The other new, expensive and whiz-bang technique for measuring whole-forest net carbon balance is eddy covariance. It is now being done at 100s of sites worldwide including several in Amazonia. I would summarize results there as net carbon uptake of one to a few tons per hectare per year during wet years and about negative 1 ton (release to the atmosphere) during dry years. But wet and dry areas are somewhat localized (except during the 2010 Amazon drought). Every year, some forested areas are dry and carbon-negative and others are wet and carbon-positive, The global net forest carbon flux seems pretty well constrained now. Not to say perfectly known, but (even local) mis-estimates by one or two orders of magnitude would be surprising. Certainly publication worthy, and I’ll be watching for them.

Cosmic rays and climate. Alas poor Svensmark; we knew him. Anyone interested in this will certainly google ‘cosmic rays climate’. The first page includes

http://www.realclimate.org/index.php/archives/2006/10/taking-cosmic-rays-for-a-spin/

and

http://iopscience.iop.org/1748-9326/3/2/024001/

and not much more I can say, not being a cosmic-ray researcher. Cosmic rays follow the 11-yr solar cycle and earth’s temperature has not. It would be even more of a challenge to implicate or imagine a multi-millennial dearth of cosmic rays during the PETM, when (by the way) we know that infrared-absorbing gases were way high in the atmosphere, and the earth was way hotter. Am I beating a dead horse here? Sorry.

Marine influences on climate. Unfortunately I can’t be PriusChat’s go-to guy here. There is way too much I don’t know about the oceans. But I will suggest that we can’t understand the Earth System without oceanographers. So please, keep paying taxes and sending their vessels to sea! Or, if you prefer, ask climate-change skeptics to finance similar missions. I don’t care WHERE the data comes from, as long as it done well and reported in a way that the results can be tested. “Science†doesn’t care and neither do I.

(An aside) fortunately we have wxman here to explain the atmosphere to us. It is another big hole in my brain. I just do terrestrial carbon cycles.

CO2 lead/lag and Richard Alley.

Mojo, I an glad that you are paying attention to Alley, because he really does the work, from high-latitude ice coring to sample analysis. And not least, because he is a better-than-average interpreter of science for the general audience.

As I understand it, matching the timing of CO2 (entrapped in bubbles) with temperature proxies (mostly oxygen isotope ratios of the ice) is problematic. For a section of an ice core that is deep (old, potentially much compressed), the two could differ by centuries or more. Unfortunately I have not located a good publication on that and it is not ‘my area’. An email to Alley or Lonnie Thompson might give us a good lead, so I’ll try that route.

But it seems to me that depending too much on the timings of those two, within the few-centuries time scale, can lead us to poor conclusions. It certainly seems not the place to look for definitive proof that CO2 is not the driver if earth energy balance.

This reply is long enough (and late enough) that I’ll end it there.

 

Around 1824 the famous mathematician Fourier described the Greenhouse effect. Around 1890, Nobel prize winner Arrhenius (1903 electrolytes) and others calculated and warned that CO2 from fossil fuels could be problem - I have one Arrhenius' GW paper from like 1897. Around 1960 we finally confirmed CO2 was rising (difficult to measure). Today, 120-years later, we are arguing about if the temperature is actually rising or not. This is a difficult measurement also, but if you had to bet your life on it, the answer is easy. The only good news here is that the time frame for warming has been a lot slower than some had thought.

 

The pioneering work that Keeling (now deceased) did on accurate CO2 measurements in the ppm range is the stuff of legend. You can read a lot of the history at the Scripps CO2 web site.

For years he did it by manometry, which is so insanely difficult that no one would follow that path today. I think Keeling first got an infrared gas analyzer (IRGA) in the early 1960's and compared it exhaustively to manometry before feeling confident to switch techniques.

Now, IRGAs are commonplace, only a few thousands $$, fast and amazingly accurate. PPM accuracy and precision measurements are routine, and 0.1 ppm 'in expert hands'. Our lab's record is 315 IRGA manual measurements in one day, which is not especially high. But 'the kids' (grad students) were getting fatigued so we did not take a run at 400.

There are also 'IRGA-on-a-chip' for about $200, but they have very short optical paths so 20 ppm is about the resolution limit. This is good enough for some carbon-cycle measurements, but not for many others. But the price is attractive and one could do some interesting experiments with a number of those chugging away at the same time.

Ah well - all that is carbon cycle and not melty ice, so off topic here.

 

Actually we insist it's not human caused. Quit wasting time and tax money trying to prove it is and use those resources on alternate energy so we can become energy independent. K?

 

When you say "it's not human caused" do you completely discard the impact of anthropogenic activity on climate, or you believe that there are different natural phenomena in place influencing GW and human activity is just a contributing factor?

 

I'd like to answer that...

I "believe that there are different natural phenomena in place influencing GW"... the rest of your second choice can be discarded.

 

So, if there is undeniable and proven beyond any doubt case that human activity altered climate somewhere in some way, you would admit that you are wrong, correct?

 

If we are talking green house gases that may or may not cause global warming then anthropogenically speaking I think we have 0.28%, or there about, impact on the climate.

 

actually it is 1.8% if you discard cloud formation. Anthropogenic greenhouse gasses (CO2, NO, CH4, O3, CFC-12, R-410A, etc) account for 2.26wt/m2 warming effect.

with 343wt/m2 solar density at earth orbit about 240wt/m2 gets through atmosphere, of which ~50% gets absorbed. 2.26/120 = 1.8%.

Now there are obviously other factors at play.. obviously planet was warming up and cooling down into ice ages for last several million years w/o any industrial greenhouse gas production.

It would be difficult to say whether planet would be cooling down and heading into ice age or heating up right now if not for human activity. But to say that human activity has no effect??