Saturday, March 20, 2010

Pass the Brazilian popcorn

There have been a number of developments on the Amazin Amazon Press Release front. Real Climate has a reply from Scott Saleska to Samanta, et al, in which Saleska clearly shows that Samata, et al's data for the short, but intense 2005 Amazon drought matches the greening that Saleska, et al. found in 2007. This getting deep down and dirty, the principals, Ranga Myneni and his student Samanta jumped the land shark here. First we had the "inventitive" quote they manufactured from Jose Marengo, which disappeared after Tim Lambert wrote to Dr. Marengo, and got a never said THAT from him.

One of the commenters at Real Climate, has found a post, flacking the paper apparently from the good Prof. Myneni. And where, the bunnies ask, did this gem show up? On Sean Hannity's web site forum. For outlanders, Hannity is one of Rupert Murdoch's hired hands, makes Chris Monckton look sane and liberal. And what appeared under Myneni's name??

An article published yesterday (March 4, 2010) in the scientific journal Geophysical Research Letters (GRL), the authors report that Amazon forests did not green-up during the 2005 drought, contrary to a 2007 report published in the prestigious journal Science and the IPCC claims about these forest response to precipitation declines. This article corrects much of the mis-information regarding the drought sensitivity of this important biome. The abstract of our article is shown below. I hope you will find this article interesting enough to write about it and/or help disseminate the news. If you wish to talk to us about this article, please contact the first author, Arindam -

The sensitivity of Amazon rainforests to dry‐season droughts is still poorly understood, with reports of enhanced tree mortality and forest fires on one hand, and excessive forest greening on the other. Here, we report that the previous results of large-scale greening of the Amazon, obtained from an earlier version of satellite-derived vegetation greenness data - Collection 4 (C4) Enhanced Vegetation Index (EVI), are irreproducible, with both this earlier version as well as the improved, current version (C5), owing to inclusion of atmosphere-corrupted data in those results. We find no evidence of large-scale greening of intact Amazon forests during the 2005 drought - approximately 11%-12% of these drought-stricken forests display greening, while, 28%-20% show browning or no-change, and for the rest, the data are not of sufficient quality to characterize any changes. These changes are also not unique - approximately similar changes are observed in non-drought years as well. Changes in surface solar irradiance are contrary to the speculation in the previously published report of enhanced sunlight availability during the 2005 drought. There was no co-relation between drought severity and greenness changes, which is contrary to the idea of drought-induced greening. Thus, we conclude that Amazon forests did not green-up during the 2005 drought.
[UPDATE: Eli acknowledges that posting in anothers name is easy on forums, which raises the point of who done it. Emails have been dispatched, but truly evil thoughts are forming. In the spirit of uninhibited bs (blog stuff) the choice appears to be between a rogue grad student, a professor in the early stages of very emeritus, or a public information officer looking for a job with Fox news - place your bets]

As Saleska points out, Samanta, et al. are playing a bit of three card monte here. The total amount of the forest imaged well enough to make a determination of browner, greener or no change was about 34%, which was composed of ~10% greener, 4% browner and 20% about the same, ie, greener was ~2.5 times more likely than browner. Added: To make this all even tastier, Saleska and Myneni were co-authors on a 2006 paper "Amazon rainforests green-up with sunlight in dry season" Fee, fie, foo fiddle-de-de, Eli smells some jealousy.

Stay tuned. Ms. Rabett has sent out for huge supplies of popcorn.

And oh yes, for your guide to all that is Samantagate, Deltoid


Anonymous said...

Interesting. I wrote to Prof. Myneni and got no reply. Then again, I am no Sean Hannity.

WTF is Myneni posting his abstract at a neocon blog for?

Required reading for curious bunnies:

Schwalm et al., Global Change Biology (2010) 16, 657–670.

In which they state:

"In seven biome–climatic season–flux groups drought
acted to increase carbon flux. In EBF climatic winter, the
onset of the tropical dry season (most EBF sites were
tropical and located in Brazil), FNEP exhibited a positive
sensitivity to normalized EF (Table 2), i.e. became more
positive during episodes of relative drought. This suggested
that dry season lamdaE was decoupled from precipitation
and vegetation had access to deep water stores
(Hutyra et al., 2007; Saleska et al., 2007; Bonal et al.,
2008). Furthermore, Amazonia is a radiation-limited
environment (Nemani et al., 2003; Teuling et al., 2009)
with relatively drier conditions linked to decreased
cloudiness, higher insolation, and greater carbon uptake
(Huete et al., 2006; Hutyra et al., 2007; Saleska et al.,
2007; Bonal et al., 2008). In contrast, peak rates of carbon
sequestration occur at light levels less than the clear sky
condition (Gu et al., 1999) and are generally greater
under diffuse light conditions (Knohl & Baldocchi,
2008). At this aggregated spatial scale it was impossible
to resolve which mechanism controlled drought response
in tropical EBF systems. However, simulation
studies suggest that both mechanisms operate simultaneously
(Baker et al., 2008)."

More research is necessary.

Of course, this all becomes moot if the Amazon forest continues to burn:


There is much, much more...someone needs to undertake a meta analysis


Steve Bloom said...

Nice catch, Eli!

Erratum: In the fourth line of your first paragraph, the reference should be to Samanta and Myneni rather than Saleska and Ranga.

WV suggests "fundire."

Martin said...

Eli, nice of you to paste in Myneni. I just had a shower.

bluegrue said...

The rmyneni account at Hannity's site has a single post. It could be anyone hiding behind that moniker.

Otherwise, good pop-corn.

bluegrue said...

When I first read this post, I managed to skip over this line in the rmyneni post at Hannity's:

"If you wish to talk to us about this article, please contact the first author, Arindam -"

It's a bit curious, that the poster first refers to "the authors" in third person, then asks Hannity to perhaps contact "us" and refers Hannity to Arindam - using his first name. I find it further of intererst, that the poster points to a gmail account, not a university one. Fearing FOIs? Nah, can't be.

I think your evil thoughts are spot on, Eli.

Hank Roberts said...

Ah, for this:

> a post, flacking the paper
> apparently , from the good
> Prof. Myneni.

substitue this:

| a post, flacking the paper,
| apparently from the good
| Prof. Myneni.

That's appropriate caution, thanks.

Horatio Algeranon said...

As Arindam Samanta says in
"Self-Contemplation - Positive Thinking" "while, every positive thought nourishes our mind, every negative thought ruins it...and as we increase in population, putting ever increasing stress on our resources, we need to think positively rather than reacting sharply to the events occuring around us..."-- Arindam Samanta

Or as Horatio likes to say, "Don't worry, be happy"

Sou said...

A lot is being made of both analyses, much for the wrong reasons as discussed.

What I am interested in is how these satellite analyses relate to on the ground changes in vegetation in the Amazon. I'm sure it's not quite as straightforward as analysing single storey vegetative cover.

The Amazon is mostly multi-storey vegetation AFAIK. Is it a bit simplistic to infer very much at all from either analysis without more study of what vegetation is greening, what is browning etc? Eg is the top canopy opening up exposing lower levels? Is the top canopy greening but lower levels dying?

I'm totally ignorant in this regard and have never been to the Amazon. So maybe someone kind can let me know just how stupid or otherwise are my questions :D

Anonymous said...

Does Brazilian popcorn come with dental floss already included?

arch stanton

Hank Roberts said...

Who says that quote disappeared?

This one?

"The way that the WWF report calculated this 40% was totally wrong, while [the new] calculations are by far more reliable and correct," said Dr. Jose Marengo, a Brazilian National Institute for Space Research climate scientist and member of the IPCC.

It was there at EurekAlert! as of 30 seconds ago.

What changed when and where?

Do you mean the whole press release has rolled off the BU page of press releases? I don't find any archive of older ones.

So did they retract, or are they trying to hide the decline in professional standards, or is it just oh that was then this is now?

Hank Roberts said...

Oh, wait, my bad, here it is at BU,
now without the Marengo quote; no change in the date next to the author's name.

An oversight, no doubt.

EliRabett said...

One of the joys of life is once you let something loose on the web, you can't call it back. There are now at least two versions of that press release out there.

Hank, trust your local bunny

Steve Bloom said...

Arch, in Brazil the dental floss is to be found on the beaches. Not sure about the popcorn.

amoeba said...

"The way that the WWF report calculated this 40% was totally wrong, while [the new] calculations are by far more reliable and correct, said Dr. Jose Marengo, a Brazilian National Institute for Space Research climate scientist and member of the IPCC."

Currently available from google cache.

Perhaps Eli might consider cutting out a copy for his scrap book!

Hank Roberts said...

> trust
Always. I just want to know where to point people with appropriate tip of the hat. For example, I don't know if EurekAlert! expects to be given notice of such little after-the-fact-check emendations, and if they get them, do they correct their copy? They're after all a major redistribution point for information and what passes as information. Heh. I'd rely on their copies if I were, say, looking for a year's best.

If the BU folks are too busy to do that, and note the date of the correction for posterity, it'd throw off my ability to trust _them_.

Anonymous said...

Lewis is taking on Leake.