Tectonic modeling casts (apparently legitimate) doubt on previous assessments of dramatic sea level rise, allegedly due to continental ice sheet melting — a comment regarding the difficulty of obtaining measuring perspective, when having nothing unmoving to stand on

Citation — to study

David B. Rowley, Alessandro M. Forte, Robert Moucha, Jerry X. Mitrovica, Nathan A. Simmons, and Stephen P. Grand, Dynamic Topography Change of the Eastern United States Since 3 Million Years Ago, Science Express,  DOI: 10.1126/science.1229180 (16 May 2013)

Citation — to press release

Canadian Institute for Advanced Research, World’s biggest ice sheets likely more stable than previously believed, CIFAR.ca (17 May 2013)

Findings

From the abstract:

Sedimentary rocks from Virginia through Florida record marine flooding during the mid-Pliocene.

Several wave-cut scarps that at the time of deposition would have been horizontal are now draped over a warped surface with a maximum amplitude of 60 m.

We modeled dynamic topography using mantle convection simulations that predict the amplitude and broad spatial distribution of this distortion. The results imply that dynamic topography and, to a lesser extent, glacial isostatic adjustment, account for the current architecture of the coastal plain and proximal shelf.

This confounds attempts to use regional stratigraphic relations as references for longer-term sea-level determinations.

Inferences of Pliocene global sea-level heights or stability of Antarctic ice sheets therefore cannot be deciphered in the absence of an appropriate mantle dynamic reference frame.

© 2013 David B. Rowley, Alessandro M. Forte, Robert Moucha, Jerry X. Mitrovica, Nathan A. Simmons, and Stephen P. Grand, Dynamic Topography Change of the Eastern United States Since 3 Million Years Ago, Science Express,  DOI: 10.1126/science.1229180 (16 May 2013) (at Abstract) (paragraph split)

Why this matters — disregarded common sense

I have always thought that the confidence some researchers placed in their calculations regarding sea level rise (or fall) and its causes was misplaced.

Common sense should indicate that — when both water and land are moving in unknown ways relative to each other — it is going to be difficult to assess what portion of the overall movement came from which source.  Yet, that has not stopped claims that proportionately dramatic sea level rise (or fall) occurred in the geologically not so distant past.

When young, I presumed that these people knew something that I did not, even though what they were saying seemed scientifically questionable, at best.  The results of the above cited study support my doubts:

For decades, scientists have used ancient shorelines to predict the stability of today’s largest ice sheets in Greenland and Antarctica.

Markings of a high shoreline from three million years ago, for example – when Earth was going through a warm period – were thought to be evidence of a high sea level due to ice sheet collapse at that time.

This assumption has led many scientists to think that if the world’s largest ice sheets collapsed in the past, then they may do just the same in our modern, progressively warming world.

However, a new groundbreaking study now challenges this thinking.

Using the east coast of the United States as their laboratory, a research team led by David Rowley, CIFAR Senior Fellow and professor at the University of Chicago, has found that the Earth’s hot mantle pushed up segments of ancient shorelines over millions of years, making them appear higher now than they originally were millions of years ago.

“Our findings suggest that the previous connections scientists made between ancient shoreline height and ice volumes are erroneous and that perhaps our ice sheets were more stable in the past than we originally thought,” says Rowley.

“Our study is telling scientists that they can no longer ignore the effect of Earth’s interior dynamics when predicting historic sea levels and ice volumes.”

© 2013 Canadian Institute for Advanced Research, World’s biggest ice sheets likely more stable than previously believed, CIFAR.ca (17 May 2013)

Caveat — and caveat rebutted

Certainly, the team’s computer modeling may be incorrect.  And certainly the Earth’s ice sheets may be noticeably dynamic.

But neither of these potential criticisms is the point.

The take-away gist is that past claims regarding sea level change depended on minimizing the effects of vertical vector land shifts.  But if we do not know (and haven’t thoroughly investigated) the magnitude, cause, or location of these — what business do we have:

(a) making seemingly precise claims about past sea level changes

and

(b) attributing those to alleged changes in the mass(es) of past ice sheets?

The moral? — If you are a sound and knowledgeable thinker, it is okay to be skeptical about a great many obviously invalidly supported scientific claims

Scientists are often just as likely to overlook analytical common sense, in situations in which they are motivated to say something dramatic, as anyone else is.

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Published:
18 May 2013 – 13:42
Author:
By BrainiYak
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Methane emission levels across the southern US are apparently higher than suspected — says a comparatively low budget science project

© 2013 Peter Free

Citation — to study

Ira Leifer, Daniel Culling, Oliver Schneising, Paige Farrell, Michael Buchwitz, and John P. Burrows, Transcontinental methane measurements: Part 2. Mobile surface investigation of fossil fuel industrial fugitive emissions, Atmospheric Environment, http://dx.doi.org/10.1016/j.atmosenv.2013.03.018 (in press, early online publication, 11 May 2013)

Citation — to press release

George Foulsham, UC Santa Barbara Scientist Studies Methane Levels in Cross-Continent Drive, University of California – Santa Barbara (15 May 2013)

Method

The team drove an RV — fitted with a roof air scoop and a gas chromatograph — (a) across the southern United States from Los Angeles to Florida in 2010 and (b) across southern California in winter 2012:

“We tried to pass through urban areas during nighttime hours, to avoid being stuck in traffic and sampling mostly exhaust fumes,” Leifer said.

“Someone was always monitoring the chromatograph, and when we would see a strong signal, we would look to see what potential sources were in the area, and modify the survey to investigate and, if possible, circumnavigate potential sources.”

© 2013 George Foulsham, UC Santa Barbara Scientist Studies Methane Levels in Cross-Continent Drive, University of California – Santa Barbara (15 May 2013) (paragraph split)

The group compared its results with data that had been collected from the European Space Agency’s now defunct (as of 08 April 2012) ENVISAT satellite.

The satellite had been equipped with the “Scanning Imaging Absorption Spectrometer for Atmospheric Chartography” (SCIAMACHY).

Findings

Emissions were most heavily concentrated around refineries, but levels varied by location and time of day:

Nighttime concentrations were dramatically enhanced when the winds died down, forming a calm, shallow atmospheric layer near the surface, according to Leifer.

© 2013 George Foulsham, UC Santa Barbara Scientist Studies Methane Levels in Cross-Continent Drive, University of California – Santa Barbara (15 May 2013) (paragraph split)

Team’s conclusion

Some of the data indicated higher levels of methane emission than scientists had previously surmised.  A portion of the discrepancy may be due to contributions from natural sources like wetlands.

Given that methane is a significantly more potent greenhouse gas than carbon dioxide, but is atmospherically active for shorter periods, Dr. Liefer thinks that it might be a more immediately productive political target for lowered emissions:

“Methane is the strongest human greenhouse gas on a political or short timescale, and also has more bang for the buck in terms of addressing climate change,” said Leifer.

“This research supports other recent findings suggesting that fugitive emissions from fossil fuel industrial activity actually are the largest methane source. This clearly indicates a need for efforts to focus on reducing these methane emissions.”

© 2013 George Foulsham, UC Santa Barbara Scientist Studies Methane Levels in Cross-Continent Drive, University of California – Santa Barbara (15 May 2013) (paragraph split)

A bit of cynicism

Given the American gas and oil industry’s political clout and conservatives’ ability to deny both science and Reality, I doubt that anyone with the ability to get things done  is going to jump on the Stop Methane bandwagon soon.

The moral? — Tracking gas emissions, their sources and volumes is difficult

Slips through our fingers, so to speak.

Predictably injected self-interested hot air means that, “We ain’t gonna be going nowhere soon” on the methane issue.

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Published:
16 May 2013 – 11:28
Author:
By BrainiYak
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Earth’s core apparently speeds up and slows down relative to the mantle — an investigation using earthquake “doublets”

© 2013 Peter Free

Citation — to study

Hrvoje Tkalčić, Mallory Young, Thomas Bodin,  Silvie Ngo and Malcolm Sambridge, The shuffling rotation of the Earth’s inner core revealed by earthquake doublets, Nature Geoscience, doi:10.1038/ngeo1813 (advance online publication, 12 May 2013)

Citation — to press release

ANU News, Earth’s centre is out of sync, Australian National University (13 May 2013)

What is an earthquake doublet — how did the team use them — and what did they find?

These are pairs of earthquake waves, of very similar magnitude, that produce very similar seismic wave forms.  According to the press release, they can occur 2 weeks to as much as 30 or 40 years apart.

The investigative idea is that, if one has paired waves of similar magnitude, one can estimate the temporal deviation between them that results from encountering variably spinning components of the Earth’s cross-section:

Here we investigate the inherent assumption of a constant rotation rate using earthquake doublets—repeating earthquakes that produce similar waveforms.

We detect that the rotation rate of the Earth’s inner core with respect to the mantle varies with time.

We perform an inverse analysis of 7 doublets observed at the College station, Alaska, as well as 17 previously reported doublets, and reconstruct a history of differential inner-core rotation between 1961 and 2007.

We find that the observed doublets are consistent with a model of an inner core with an average differential rotation rate of 0.25–0.48° yr−1 and decadal fluctuations of the order of 1° yr−1 around the mean.

The decadal fluctuations explain discrepancies between previous core rotation models and are in concordance with recent geodynamical simulations.

© 2013 Hrvoje Tkalčić, Mallory Young, Thomas Bodin,  Silvie Ngo and Malcolm Sambridge, The shuffling rotation of the Earth’s inner core revealed by earthquake doublets, Nature Geoscience, doi:10.1038/ngeo1813 (advance online publication, 12 May 2013) (at Abstract) (paragraph split)

Put into context by the press release:

“This is the first experimental evidence that the inner core has rotated at a variety of different speeds,” Associate Professor Tkalcic said.

“We found that, compared with the mantle, the inner core was rotating more quickly in the 1970s and 1990s, but slowed down in the 80s.

The most dramatic acceleration has possibly occurred in the last few years, although further tests are needed to confirm that observation.

“It’s stunning to see that even 10, 20 or 30 years apart, these earthquakes look so similar. But each pair differs very slightly, and that difference corresponds to the inner core. We have been able to use that small difference to reconstruct a history of how the inner core has rotated over the last 50 years,” he said.

© 2013 ANU News, Earth’s centre is out of sync, Australian National University (13 May 2013) (paragraph split)

Caveat

Some of the reasoning involved seems backward to (probably ignorant) me.

How can we be sure that the seismic doublets from 30 to 40 years apart are actually near identical?  What if one wave had been altered by something that we have not considered, so as to have made it come out as having been presumably identical to the one we wanted to pair it with?  Why are we assuming that the planet, as a whole, is virtually identical even decades apart?

By presuming that two temporally far apart waves are (or were) close to identical — and then looking for a core speed-induced differences between them — we may be overlooking other reasons for doublet arm’s differences or similarities.

The moral? — Cool reasoning, but I am a bit skeptical of the method

I would have been happier, if the team had restricted itself to using doublets that occurred very close together in time.  That way we could infer that the planet (as a whole) was pretty much identical for each.

But this skepticism may simply be my ignorance speaking.

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Published:
14 May 2013 – 12:46
Author:
By BrainiYak
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Parental addictions forecast 69 percent higher rate of depression in their eventually adult children — as compared to children of non-addicts

© 2013 Peter Free

Citation — to study

Esme Fuller-Thomson, Robyn B. Katz, Vi T. Phan, Jessica P.M. Liddycoat, and Sarah Brennenstuhl, The long arm of parental addictions: The association with adult children’s depression in a population-based study, Psychiatry Research, doi:10.1016/j.psychres.2013.02.024 (in press, early online publication of corrected proof, 06 May 2013)

Citation — to press release

Dominic Ali, Parental addictions linked to adult children’s depression, University of Toronto (09 May 2013)

Methods and findings

From the press release:

[I]nvestigators examined the association between parental addictions and adult depression in a representative sample of 6,268 adults, drawn from the 2005 Canadian Community Health Survey.

Of these respondents, 312 had a major depressive episode within the year preceding the survey and 877 reported that while they were under the age of 18 and still living at home that at least one parent who drank or used drugs “so often that it caused problems for the family”.

© 2013 Dominic Ali, Parental addictions linked to adult children’s depression, University of Toronto (09 May 2013) (paragraph split)

From the abstract:

Using a regionally representative sample of 6268 adults from the 2005 Canadian Community Health Survey (response rate=83%), we investigated the association between parental addictions and adulthood depression controlling for four clusters of variables:

adverse childhood experiences,

adult health behaviors,

adult socioeconomic status

and other stressors.

After controlling for all factors, adults exposed to parental addiction had 69% higher odds of depression compared to their peers with non-addicted parents . . . .

The relationship between parental addictions and depression did not vary by gender.

These findings underscore the intergenerational consequences of drug and alcohol addiction and reinforce the need to develop interventions that support healthy childhood development.

© 2013 Esme Fuller-Thomson, Robyn B. Katz, Vi T. Phan, Jessica P.M. Liddycoat, and Sarah Brennenstuhl, The long arm of parental addictions: The association with adult children’s depression in a population-based study, Psychiatry Research, doi:10.1016/j.psychres.2013.02.024 (in press, early online publication of corrected proof, 06 May 2013) (paragraph split and reformatted)

Caveats

Two sample questions (from a larger pile of such):

(1) Are depressed people more likely to recall crappy childhoods than not depressed folk?

(2) Are adult children of addicts more likely to have inherited genes for mood disorders?  Yes, according to previous research.

If largely so, the study’s implied causative connection between a crappy childhood (and no more) and depression may vanish.

The moral? — Sounds hypothetically probable — but 69 percent more likely is a surprisingly small effect, given the purported causation

Giving from an identical background myself, I often wonder whether my unpleasant childhood molded my often less than sunny outlook — or whether I simply inherited some of the genes my parents carried, which encouraged them toward mood disorder(s) and self-medication.

And, in both cases, I wonder whether I simply lack a protective gene cluster that protects other people from similar backgrounds.

I am pretty sure there is scientifically a lot more to this association between childhood quality and depression.

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Published:
13 May 2013 – 16:13
Author:
By BrainiYak
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Yersinia pestis is now demonstrated to have caused the 6th through 8th Century Justinian equivalent of the “Black Death” — allegedly making Yersinia pestis the causative agent for three pandemics, including the two more recent ones which spanned the 14 – 17th and 19th – 21st Centuries

© 2013 Peter Free

Citation — to study

Michaela Harbeck, Lisa Seifert, Stephanie Hänsch, David M. Wagner, Dawn Birdsell, Katy L. Parise, Ingrid Wiechmann, Gisela Grupe, Astrid Thomas, Paul Keim, Lothar Zöller, Barbara Bramanti, Julia M. Riehm, and Holger C. Scholz, Yersinia pestis DNA from Skeletal Remains from the 6th Century AD Reveals Insights into Justinianic Plague, PLoS Pathogens 9 (5): e1003349, DOI: 10.1371/journal.ppat.1003349 (02 May 2013)

Citation — to press release

Press and Public Relations, Scientists confirm that the Justinianic Plague was caused by the bacterium Yersinia pestis, Johannes Gutenberg Universität – Mainz (10 May 2013)

Background

From the abstract:

Yersinia pestis [see here], the etiologic agent of the disease plague, has been implicated in three historical pandemics.

These include the third pandemic of the 19th and 20th centuries, during which plague was spread around the world, and the second pandemic of the 14th–17th centuries, which included the infamous epidemic known as the Black Death.

Previous studies have confirmed that Y. pestis caused these two more recent pandemics.

However, a highly spirited debate still continues as to whether Y. pestis caused the so-called Justinianic Plague of the 6th–8th centuries AD.

© 2013 Michaela Harbeck, Lisa Seifert, Stephanie Hänsch, David M. Wagner, Dawn Birdsell, Katy L. Parise, Ingrid Wiechmann, Gisela Grupe, Astrid Thomas, Paul Keim, Lothar Zöller, Barbara Bramanti, Julia M. Riehm, and Holger C. Scholz, Yersinia pestis DNA from Skeletal Remains from the 6th Century AD Reveals Insights into Justinianic Plague, PLoS Pathogens 9 (5): e1003349, DOI: 10.1371/journal.ppat.1003349 (02 May 2013) (at Abstract) (paragraph split)

Method

The team assumed that plague might claim enough lives simultaneously to result in people being buried together.  They collected teeth from 19 people, from 12 separate burials, from the 6th Century cemetery at Aschheim.

Carbon dating was done on three sets of remains, resulting in individual death dates between 431-544, 443-566, and 435-631.

Teeth from all 19 individuals were analyzed by a DNA laboratory in Munich.  And those from an included 4 were also analyzed by a lab in Mainz:

We attempted to genotype all of the positive samples.

However, likely due to differences in DNA preservation among the samples we were only able to gain reproducible results from samples from one individual, A120 (Table 2).

Note that this was the only individual that was found to be Y. pestis-positive with all three PCR approaches (Table 1).

© 2013 Michaela Harbeck, Lisa Seifert, Stephanie Hänsch, David M. Wagner, Dawn Birdsell, Katy L. Parise, Ingrid Wiechmann, Gisela Grupe, Astrid Thomas, Paul Keim, Lothar Zöller, Barbara Bramanti, Julia M. Riehm, and Holger C. Scholz, Yersinia pestis DNA from Skeletal Remains from the 6th Century AD Reveals Insights into Justinianic Plague, PLoS Pathogens 9 (5): e1003349, DOI: 10.1371/journal.ppat.1003349 (02 May 2013) (at Genotyping Analysis) (paragraph split)

Authors’ conclusion — Yersinia pestis did it

From the paper’s Discussion section:

Our analyses conducted in two separate aDNA laboratories independently confirmed our previous results [15] that some humans buried in the 6th century Ascheim cemetery were infected with Y. pestis.

These findings confirm that Y. pestis was the causative agent of the Justinianic Plague and should end the controversy over the etiological agent of the first plague pandemic.

This outcome is contrary to a recent study [3] that questioned whether Y. pestiswas indeed the causative agent of the first pandemic based upon the assumption that only strains from major branches one and two are pathogenic to humans, which they estimated to have emerged only in the 13th century AD.

However, Cui et al. [11] recently determined that most Y. pestis lineages are capable of causing human plague and suggested that this capability has been present since Y. pestis evolved from its Y. pseudotuberculosis ancestor approximately 1,500–6,400 years ago.

Thus, they concluded that Y. pestis strains pathogenic to humans already existed long before the beginning of the first pandemic.

© 2013 Michaela Harbeck, Lisa Seifert, Stephanie Hänsch, David M. Wagner, Dawn Birdsell, Katy L. Parise, Ingrid Wiechmann, Gisela Grupe, Astrid Thomas, Paul Keim, Lothar Zöller, Barbara Bramanti, Julia M. Riehm, and Holger C. Scholz, Yersinia pestis DNA from Skeletal Remains from the 6th Century AD Reveals Insights into Justinianic Plague, PLoS Pathogens 9 (5): e1003349, DOI: 10.1371/journal.ppat.1003349 (02 May 2013) (at first paragraph under Discussion) (paragraph split)

Caveats — too few sample cases

I doubt that this paper will end the controversy.  Nineteen people from one cemetery across such a widely involved region “ain’t” many.  And having had only 4 of the 19 results confirmed in different lab is still fewer.

Given these (i) low and geographically unrepresentative numbers, in combination with  (ii) what can go wrong with testing poorly preserved DNA, my hunch is that the authors’ confidence in the persuasiveness of their conclusion is optimistic.

If the authors are going to assume that 19 people, in one cemetery, can reliably sit in for hundreds of thousands (if it be that) across three centuries, they are probably going to have a spirited evidentiary fight.

This is so because they are implicitly assuming that:

(a) these 19 people shared symptoms that the historical record ascribes to the Justinian Pestilence,

(b) that symptoms of the Justinian Pestilence were reliably unique enough to distinguish its causative organism from all others,

and

(c) that their 19 people died from the organism that had caused the preponderance of all Pestilence deaths — rather than from a sideshow organism that reared its head where they lived, while another, and more numerically devastating one, was carrying out its carnage elsewhere.

In other words, the authors — with significant rational justice — are assuming that the nastiness that we attribute to Yersinia pestis during the second two outbreaks can be assumed to have been representative of it during the first.

But that is (arguably) circular logic.  What if their Yersinia was an evolving predecessor to those which went rampant later in time, and something else had actually caused the bulk of the Justinian deaths?

If the authors’ sample of Yersinia during the Justinian epidemic is confined to only 19 people in 1 cemetery, we cannot be sure that it was prevalent across a wider region and range of time.  Nor can we be sure that it was as virulent as the second two epidemics are assumed to have been.

Until we have more numbers, in more places, we cannot be sure of Yersinia’s geographic or temporal range (even within the Justinian outbreak) — or, given disputes over the meaning of the organism’s mutations and possible DNA contamination, its mortality-inducing virulence.

The moral? — Nice work, but arguably too confident a conclusion

As is typical with science, we will have to wait for confirmatory studies — not only of the 19 set samples this study took, but from additional ones taken across a wider geographic region.

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Published:
10 May 2013 – 13:19
Author:
By BrainiYak
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Somewhat botched communication from the US Forest Service — regarding the carbon sequestration value of urban trees — an example of dumbed down science analysis that goes nowhere — and a comment on the desirability of not using imprecise language to communicate units of measurement

Citation — to study

David J. Nowak, Eric J. Greenfield, Robert E. Hoehn, and Elizabeth Lapoint, Carbon storage and sequestration by trees in urban and community areas of the United States, Environmental Pollution 178: 229–236, http://dx.doi.org/10.1016/j.envpol.2013.03.019 (July 2013)

Citation — to Forest Service press release

Press Office, US urban trees store carbon, provide billions in economic value, US Forest Service (07 May 2013)

The supposedly good news about urban trees contribution to carbon sequestration in aid of slowing global warming

From the study’s abstract:

Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change.

Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover.

These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m−2 [meaning kilograms of carbon per square meter of ground area] of tree cover and sequestration densities average 0.28 kg C m−2 of tree cover per year.

Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes ($50.5 billion value . . . ) and annual sequestration is estimated at 25.6 million tonnes ($2.0 billion value . . . ).

© 2013 David J. Nowak, Eric J. Greenfield, Robert E. Hoehn, and Elizabeth Lapoint, Carbon storage and sequestration by trees in urban and community areas of the United States, Environmental Pollution 178: 229–236, http://dx.doi.org/10.1016/j.envpol.2013.03.019 (July 2013)

The Forest Service synopsized this to mean that:

From New York City’s Central Park to Golden Gate Park in San Francisco, America’s urban forests store an estimated 708 million tons of carbon, an environmental service with an estimated value of $50 billion, according to a recent U.S. Forest Service study.

“With expanding urbanization, city trees and forests are becoming increasingly important to sustain the health and well-being of our environment and our communities,” said U.S. Forest Service Chief Tom Tidwell.

“Carbon storage is just one of the many benefits provided by the hardest working trees in America.

“I hope this study will encourage people to look at their neighborhood trees a little differently, and start thinking about ways they can help care for their own urban forests.”

The total amount of carbon stored and sequestered in urban areas could increase in the future as urban land expands.

Urban areas in the continental U.S. increased from 2.5 percent of land area in 1990 to 3.1 percent in 2000, an increase equivalent to the area of Vermont and New Hampshire combined.

If that growth pattern continues, U.S. urban land could expand by an area greater than the state of Montana by 2050.

© 2013 Press Office, US urban trees store carbon, provide billions in economic value, US Forest Service (07 May 2013) (paragraphs split)

If you were paying attention, you will have noticed that the numbers for “tonnes” and “tons” don’t match up in the two publications

That’s because there is a scientifically noticeable difference in magnitude between the two units:

In American English, a ton is a unit of measurement equaling 2,000 pounds.

In non-U.S. measurements, a ton equals 2,240 pounds. A tonne, also known as a metric ton, is a unit of mass equaling 1,000 kilograms.

American English speakers generally have no use for tonne, so the spelling rarely appears in U.S. publications.

Elsewhere, fastidious publications use the appropriate spellings for the units of measurement.

© 2013 Ton vs. tonne, Grammerist.com (21 March 2011)

I would say that the alleged US practice has its unscientific head up its behind.

The Forest Service Press Office competently changed the study’s metric tonnes into American tons — but without telling its often ignorant readers what it was doing and why.

That is a missed opportunity for science education.  And the oversight confirms the Grammerist’s tacit indictment of American sloppiness.

More important, what about the study’s questionable methodology?

Six states and 28 cities?  Is that supposed to statistically represent the geographic diversity of the United States?

I don’t think it is mathematically possible to generalize data from only 6 states to represent approximate urban tree coverage across even the contiguous states.

My substantial American travels indicate that landscapes, cities, neighborhoods, and even streets are so radically different that coming up with a model to represent the totality is highly questionable — without first gathering an enormous amount of urban data that the Forest Service, being focused primarily on non-urban land, is unlikely to have or be able to obtain.

And then there is the press release’s clumsy segue into reality

Recall that the press release said:

The total amount of carbon stored and sequestered in urban areas could increase in the future as urban land expands.

But then it turns on a metaphorical dime and adds:

Last year, Nowak and Eric Greenfield, a forester with the Northern Research Station and another study co-author, found that urban tree cover is declining nationwide at a rate of about 20,000 acres per year, or 4 million trees per year.

© 2013 Press Office, US urban trees store carbon, provide billions in economic value, US Forest Service (07 May 2013) (paragraphs split)

And the press release concludes without making any analytical attempt to harmonize the two competing statements.

This lack of intellectual rigor is further highlighted by a list of the fifty American states and the estimated mass of stored carbon that their urban trees hold

Again, with no mention of how legitimate it was (or wasn’t) is to extrapolate from a model based on only 6 states to all the rest.

The moral? — Questionable numbers and mostly meaningless implications

The only reasonably solid impression one might get from both publications is that urban trees may be an environmentally good thing.  Which is almost certainly all that the Forest Service cared to convey.

But the Service lost a valuable opportunity to educate the public about the ins and outs of scientific research, analysis, and units of measurement language.

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Published:
8 May 2013 – 13:27
Author:
By BrainiYak
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An apparently clever way of collecting and treating beach seaweed for other purposes, including biofuel

© 2013 Peter Free

Citation — to press release

Asociación RUVID, The University of Alicante invents a system to clean seaweed from beaches, AlphaGalileo Foundation (03 May 2013)

Moving bulky things around has obvious costs, and sometimes it’s better to get most of the processing done on site

From the press release:

A research group at the University of Alicante (Spain) has invented an algae removal and treatment system that turns this underused residue into a renewable source of energy: biomass.

[A] according to the team led by Professor Irene Sentana Gadea, the system is cheaper, efficient and more environmentally friendly than the procedure used now by local authorities.

The system is based on a moving platform with wheels where three hoppers are installed. The first receives shovelfuls of wet seaweed with sand attached. Seawater is pumped in and poured back into the sea dragging the sand with it.

In the next hopper, water purified with a solar-powered device would wash most of the residual salt from the algae, and in the third hopper it would be dried with air heated also by solar energy.

The clean and dry seaweed could be then pressed by a system similar to the one used by rubbish trucks or converted into bales or pellets, ready to be commercialized. No chemical products would be used in the process.

© 2013 Asociación RUVID, The University of Alicante invents a system to clean seaweed from beaches, AlphaGalileo Foundation (03 May 2013) (paragraphs split)

This method contrasts with the one in current use, which collects seaweed from beaches, without processing it and moves it to landfills — along with its integrated sand, water, and salt — where it sits (mostly) wasted and acts as a salt polluter.

The moral? — An apparently beneficent combination of science and engineering

It will be interesting to see the mechanism in action, once it is manufactured.

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Published:
6 May 2013 – 12:26
Author:
By BrainiYak
Categories:
Comments:
None

Sahara’s Laperrine’s olive tree — its clonal survival strategy worked for in the past — but allegedly may be unavoidably self-defeating now — (i) an illustration of possible diminished genetic fitness in climate changing times or (ii) biologists jumping to unwarranted conclusions

© 2013 Peter Free

Citation — to study

G. Besnard, F. Anthelme, and D. Baali-Cherifc, The Laperrine’s olive tree (Oleaceae): a wild genetic resource of the cultivated olive and a model-species for studying the biogeography of the Saharan Mountains, Acta Botanica Gallica 159 (3): 319-328, DOI: 10.1080/12538078.2012.724281 (26 November 2012)

Citation — to press release

Media Centre – Scientific Newssheets, The Sahara olive tree: a genetic heritage to be preserved, Institut de Recherche pour le Développement (IRD) (March 2013)

Background

From the abstract:

The Laperrine’s olive is an iconic subspecies of Olea europaea (Oleaceae) with a narrow distribution in the Saharan Mountains, from south Algeria to northeast Sudan.

In natural habitats, multi-centennial individuals occur in very harsh environmental conditions and mainly reproduce vegetatively, but it appears that sexuality may be easily restored under favourable conditions.

Crosses between the Laperrine’s olive and other olive diploid subspecies (subspp.cuspidata and europaea) have been recently reported.

Plastid DNA analyses also indicate that the Laperrine’s olive has already been used during the secondary diversification of the cultivated Mediterranean olive in the Maghreb.

This taxon could therefore be used as source of genes for the breeding of new olive cultivars, particularly to improve drought tolerance.

© 2012 G. Besnard, F. Anthelme, and D. Baali-Cherifc, The Laperrine’s olive tree (Oleaceae): a wild genetic resource of the cultivated olive and a model-species for studying the biogeography of the Saharan Mountains, Acta Botanica Gallica 159 (3): 319-328, DOI: 10.1080/12538078.2012.724281 (26 November 2012) (paragraph split)

Of specific interest — evolutionary fitness now limited by past climate accommodations

From the press release:

It grows in the middle of the Sahara desert at an altitude of between 1400 and 2800m, spanning southern Algeria , Niger and northern Sudan.

In order to survive in this inhospitable environment over the past several million years, it had to adapt to extremely arid conditions.

In order to preserve this exceptional genetic heritage over the course of time, it developed an unusual reproductive strategy. As researchers have demonstrated in a recent synthetic study, it reproduces through vegetative or clonal growth.

The limited gene flow among populations and its vegetative reproduction method resulted in less genetic mixing over long periods of time.

Under current climatic conditions, the number of trees also tends to decrease.

This combination of factors leads to the gradual erosion of the genetic diversity, which lowers the ability of the Laperrine’s olive tree to adapt to environmental changes and means this subspecies is potentially endangered in the long term.

© 2013 Media Centre – Scientific Newssheets, The Sahara olive tree: a genetic heritage to be preserved, Institut de Recherche pour le Développement (IRD) (March 2013) (paragraphs split)

The idea here is that having had to resort to clonal reproduction (so as to cope with its isolation in the harshness of the high Sahara) Laperinne’s olive tree lost access to sexual gene mixing, which might have given it a better statistical stab at coping with anticipated coming climatic change.

Isn’t this a form of jumping to conclusions?

I have a few problems with the press release’s analysis:

First, nobody knows how the Saharan climate is going to develop with the generalized global warming that we are experiencing.

Implicitly assuming that Laperrine’s current (clone-based) fitness will somehow be dramatically reduced in the foreseeable future seems too much of leap.

Second, human beings (presumably) have been chopping Laperrine’s olive trees down for fuel and other purposes, thereby (at least partially) leading to their endangered status.

That hardly qualifies as an indicator of reduced genetic fitness — unless one assumes that a “fitter” plant would have grown both legs and the ability to shoot back.

Third, increasing severe aridity always leads to diminished macro-sized plant populations.  Just because populations are reduced in numbers doesn’t make those that are left less fit.

Presumably, those specimens that are left are the most suited among their “clan”. Which, in the case of the mouth-drying Sahara, would be an enviable performance by any macro organism.

The moral? — A biologically admirable tree and without more, conclusions about its allegedly diminished future fitness should probably not be drawn

Our assumptions often get the best of us.

My guess would be that Laperinne’s most proprotionally significant “fitness” survival problem has been people, not climate or geography.

And I would not be betting (yet) on which way the Saharan climate is going to go in the foreseeable future.

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Published:
3 May 2013 – 17:11
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By BrainiYak
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Major depression appears to be grossly over-diagnosed and treated in the United States — says an apparently indicative study

© 2013 Peter Free

Citation — to study

Ramin J. Mojtabai, Clinician-Identified Depression in Community Settings: Concordance with Structured-Interview Diagnoses, Psychotherapy and Psychosomatics 82 (3): 161-169, DOI: 10.1159/000345968 (April 2013)

Citation — to press release

Natalie Wood-Wright, Over-diagnosis and over-treatment of depression is common in the U.S., Johns Hopkins Bloomberg School of Public Health (30 April 2013)

Methods

Dr. Mojitabai arranged “structured” interviews with 5,639 allegedly patients, culled from the mental health component of the 2009-2010 National Survey of Drug Use and Health.

These people had been identified by medical providers as suffering from a major depressive episode within the 12 month period prior to the interview.

What is a “major depressive episode”?

The Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) defines it as — accurately synopsized by Canadian psychiatrist Phillip W. Long, MD at his website, Internet Mental Health:

In a Major Depressive Episode, an individual has persistent depressed mood or loss of interest or pleasure for at least 2 weeks, and this negative mood represents a change from previous functioning.

In addition, the individual must have 5 (or more) symptoms, nearly every day, of the following:

(1) depressed mood,

(2) loss of interest or pleasure,

(3) significant weight loss/gain (when not dieting),

(4) insomnia/hypersomnia,

(5) either observable physical slowing of thinking or movements, or the opposite – observable agitation,

(6) fatigue or loss of energy,

(7) feelings of worthlessness or excessive or inappropriate guilt (not merely self-reproach or guilt about being sick),

(8) diminished ability to think or concentrate, or indecisiveness,

(9) recurrent thoughts of death (not just fear of dying) or suicide.

These symptoms cause significant distress or life impairment, and are not due to a drug, medication or general medical condition.

These depressive symptoms are not due to normal Bereavement.

© 2011 Phillip W. Long, MD, Major Depressive Disorder (Unipolar Affective Disorder), Internet Mental Health (2011)

I selected Dr. Long’s description (based on my third year medical school clinical rotation in psychiatry) in preference to WebMD’s.  The latter is surprisingly imprecise and may culturally indicate why Dr. Ramin J. Mojtabai’s study got the results that it did.

Psychiatric diagnoses have critical elements that must be fulfilled, for the diagnosis to apply.  Hence Dr. Mojtabai’s use of structured interviews.

Notice that I am not saying that . . .

. . . the DSM-IV (or its coming successor, the DSM-V) is necessarily an accurate indicator of mental illness.

In school and still today, I suspect that a significant proportion of the DSM’s illnesses are figments of imagination, some based on the medical establishment’s self-interest, that are ultimately based on a misunderstanding of the normal distribution of personal character and culture throughout any human population.

For example, just because someone is a “pain in the ass” or dysfunctional does not necessarily make him or her “nuts”.  To wit, at least some of the DSM’s “character disorders.”

Fringe people — those permanently or temporarily located toward the edges of the bell-shaped curve — are probably not by definition necessarily ill.  Unless, of course, we want to agree that anyone a few standard deviations away from the norm is automatically “sick” or “crazy”.  (Just think what that might do to History’s most exceptionally valuable people.)

Alternatively, given the complexity of the human brain and the many ways in which it can go structurally and biochemically wrong, I do not quarrel with aspects of the “medical model” of psychiatric illness.

Study findings

From the abstract:

Only 38.4% of participants with 12-month clinician-identified depression met the 12-month MDE criteria.

Older adults were less likely than younger adults to meet the criteria – only 14.3% of those 65 years old or older met the criteria, whereas participants with more education and those with poorer overall health were more likely to meet the criteria.

Participants who did not meet the 12-month MDE criteria reported less distress and impairment in role functioning and used fewer services.

A majority of both groups, however, were prescribed and used psychiatric medications.

Conclusions:

Depression overdiagnosis and overtreatment is common in community settings in the USA.

There is a need for improved targeting of diagnosis and treatments of depression and other mental disorders in these settings.

© 2013 Ramin J. Mojtabai, Clinician-Identified Depression in Community Settings: Concordance with Structured-Interview Diagnoses, Psychotherapy and Psychosomatics 82 (3): 161-169, DOI: 10.1159/000345968 (April 2013) (at Abstract) (paragraphs split, underline added)

“Common” is an understatement

If only 38 percent of the people diagnosed were actually ill, that means that 62 percent were not.

Even for complex medicine, that is a horrendous error rate.  For something so comparatively simple (in the psychiatric field) as diagnosing major depression, it’s absurd.

The problem of non-specialists’ frequent arrogance, when it comes to psychiatry and psychology

During my medical training, I noticed a profound cultural disrespect for psychiatrists and, sometimes, psychologists.  I understood where the contemptuous bias came from, given the long road of nonsense that psychiatry has evolved through.

But my personal experience, obtained while training with a handful of talented “medical model” psychiatrists, demonstrated how challenging diagnosis and appropriate treatment are.

I spent many hours with one, in particular, as he honed in on mental problems that has defeated prior providers.  His patients were so effusively grateful that sometimes their expressed gratitude brought a sheen to my eyes.

I was also fortunate in working with a pair of talented psychologists, who kept a group of tragically tormented outpatients on as even a keel as possible.  Those sessions were perhaps the most personally rewarding of my medical training.

There is nothing like raw courage, displayed in those who literally struggle with each minute, to make one appreciate the tragedy of the human condition and the spirit that sometimes triumphs over its immense suffering.

You will not convince me that this small sample of mental health specialists’ insight, expertise, and personal warmth can be capably emulated by any but a vanishingly small group of medical primary care generalists.  The required mindset is radically different.  The challenges more amorphous.  And the time required for exhibiting therapeutic excellence is usually unaffordable in the primary care setting.

The moral? — Diagnostic errors in identifying depression are huge — and are perhaps due to our cultural penchant for avoiding making referrals to mental illness professionals

I could be wrong.  But I think that Dr. Mojtabai’s study strongly points that way.

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Published:
2 May 2013 – 15:07
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By BrainiYak
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The “special section” cancer overview contained in Science’s 29 March 2013 issue is important reading — a reminder that “personalized” medicine claims are mostly nonsense — and that, once the volume of driver mutations get rolling and metastasize, hope for cure fades

© 2013 Peter Free

Citation

Special Section: Cancer Genomics, Science 339 (6127): 1539-1570 (29 March 2013) (the Section’s included articles are free, provider that the reader registers with the Science website)

The two most important insights

From Jocelyn Kaiser:

[T]umors often contain many subsets of cells that are related but genetically distinct. As a tumor evolves, identical cells apparently split off and develop new mutations or other errors, like a tree growing many branches.

This means that two parts of the same tumor, as well as the metastases that form when cancer spreads, can look very different genetically.

The extent of this intratumor heterogeneity has shaken cancer biologists and clinicians.

They’re rethinking major projects to tally up cancer mutations, for example, because the data so far have been based on a single sample for each tumor type.

And physicians worry that the new studies suggest that the growing practice of analyzing the genetic and molecular characteristics of a single tumor biopsy to guide patient treatment may sometimes mislead.

A cancer’s heterogeneity could also account for why much-heralded new drugs that target specific gene mutations may keep tumors in check for a time but almost inevitably stop working; they may merely lift a lid on a small population of drug-resistant cells and give them a chance to grow.

© 2013 Jocelyn Kaiser, The Downside of Diversity, Science 339 (6127): 1543-1545, DOI: 10.1126/science.339.6127.1543 (29 March 2013) (at page 1543) (paragraphs split)

And from Bert Vogelstein et al:

Over the past decade, comprehensive sequencing efforts have revealed the genomic landscapes of common forms of human cancer.

For most cancer types, this landscape consists of a small number of “mountains” (genes altered in a high percentage of tumors) and a much larger number of “hills” (genes altered infrequently).

To date, these studies have revealed ~140 genes that, when altered by intragenic mutations, can promote or “drive” tumorigenesis.

A typical tumor contains two to eight of these “driver gene” mutations; the remaining mutations are passengers that confer no selective growth advantage.

Driver genes can be classified into 12 signaling pathways that regulate three core cellular processes: cell fate, cell survival, and genome maintenance.

Bert Vogelstein, Nickolas Papadopoulos, Victor E. Velculescu, Shibin Zhou, Luis A. Diaz Jr., and Kenneth W. Kinzler, Cancer Genome Landscapes, Science 339 (6127): 1546-1558, DOI: 10.1126/science.1235122 (29 March 2013) (at Abstract) (paragraph split)

One implied assumption may be incorrect, in my biological opinion

Partially implied in the Vogelstein article is the idea that “passenger mutations” don’t do much in regard to driving tumorigenesis.  That is undoubtedly true from a “what’s going on now” perspective.

But what the authors may be overlooking is that any time one has a pool of easily mutated material, one simultaneously has a reservoir from which to mold future, potentially fitness-enhancing mutations.  These supposedly untroubling passenger genes may become functionally more important, after “today’s” driver genes lose their ability (under therapeutic attack) to keep the tumor progressing.

Consequently, I am not as sanguine as the Vogelstein group seems to be that we may be on the cusp of getting a therapeutic handle on intratumoral genetic diversity.

The moral? — Biological goalposts have a way of moving themselves

Were it not for that, Life would have died out under the onslaught of challenging environmental conditions.

Biology’s balance between stasis and “moving” mutation is a tenuously balanced one.  It is not surprising that “mistakes” happen and cells go off in an incredible variety of holistically unhealthy directions.  From a statistical point of view, I imagine that tumorigenesis is going to be with us for a long time.  No sooner will we have conquered one form, when another will raise its head.

Part of my reasoning for this medical realism/pessimism comes from our increasing awareness of the genuinely incredible range and depth of biological mechanisms and interrelationships.

For example, the 05 April 2013 issue of Science takes a look at supposedly “dead” enzymes that aren’t.  What was once thought to be a variety of obsolete biological material turns out to comprise a variety of “pseudoenzymes” that have an apparently wide variety of present day cellular functions.  See:

Mitch Leslie, ‘Dead’ Enzymes Show Signs of Life, Science 340 (6128): 25-27, DOI: 10.1126/science.340.6128.25 (05 April 2013)

None of this intended to discourage our enthusiasm in attacking the variety of diseases that we lump under the generic name “cancer”.

But it is posed as a caveat against making early pronouncements regarding the timely arrival of the Promised Therapeutic Land.

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Published:
1 May 2013 – 12:53
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By BrainiYak
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