"Improper" Tree Hazard Assessments?

The Summer 2020 issue of FSEEE Forest News argues that the Forest Service improperly uses tree hazard assessments to justify closing public lands.

Based on the article, it appears that FS spokespeople have not always done a good job communicating the reason for post-fire closure areas.  There are many reasons to close areas post-fire, but tree risk assessments by themselves would probably not justify backcountry trail closures. 

The FS Field Guide for Hazard Tree Identification and Mitigation cited in the article applies a numerical probability assessment to hazards by scoring Failure Indicators and adding these with Damage Potential to obtain a numerical Hazard Rating.   This methodology would be familiar to any arborist and follows standard arboriculture practices.  If there are dead or damaged trees around developed FS facilities or campgrounds than clearly there would be a high Hazard Rating and it would make sense to close those areas until the hazard can be mitigated.  But applying this same methodology to backcountry trails would result in scores that are relatively low because of the sparse or nonexistent targets for the hazard trees. So on this point the Forest News article is correct: hazard trees alone do not justify backcountry forest closures.

However, there are other hazards in recently burned areas besides dead trees, including active restoration/revegetation projects, burned-out root systems, unstable soils, potential debris flows, and obscured or impassable trails.  It may make sense to close these areas to the public until trails can be repaired or ongoing restoration work is completed.  

Carbon offset controversy

 

https://carbon180.medium.com/in-search-of-carbon-removal-offsets-42abf71b3ccc

https://forestpolicypub.com/2020/12/10/bloomberg-green-on-the-nature-conservancy-and-meaningless-carbon-offsets/

The Problem with Nutrigenomics

"Personalized nutritional counseling is a burgeoning field. Several companies, including Vitagene, Nutrigenomix and DNAFit, are already offering individualized dietary counseling.  Their efforts are based mostly on genetic testing, but scientists have only just begun to explore the links between DNA and good nutrition. “I think companies offering personalized dietary advice are probably running ahead of the evidence,” said John Mathers, director of the Human Nutrition Research Center at Newcastle University in Britain." [NYTimes Blog]

Introduction

Science skeptics have recently reviewed these services, and found plenty of quackery. [Science Based Medicine] [Skeptical Raptor]

However, there is some research to back up the idea that genetic testing can provide insights into metabolic disorders.  There may be as many as 200 SNPs for which there are proven metabolic effects, and only a subset of these alter nutrient requirements in a significant portion of the population [e.g., the rs1801133 MTHFR SNP and folate requirement in 15–30% of the population (Solis et al., 2008) and the rs12325817 PEMT SNP and choline requirement in 20–45% of the population (da Costa et al., 2006)].

What do genetic testing services measure?

The human genome consists of about 3 billion nuceleotide bases, each of which is either A,C, T, or G.  A reference genome based on the similarities of all genotyped humans has been assembled, along with a corresponding reference database of all of the point "mutations" where individuals differ from that baseline.  So far, scientists have documented about 150 million of these single nucleotide polymorphisms, called SNPs.  The average person doesn't have all of these differences, however; most people have about 3 millions SNPs that differentiate them from the reference human genome.   Since 3 million is about 0.1% of the 3 billion base pairs, most humans differ from each other by about 0.1% of our DNA. Ancestry genomic testing services like 23andme test for a few hundred thousand SNPs for $100-$200.  For $1000-10,000 a complete genomic sequence can be obtained.  (there are about 3 billion bases total.  

Examples: MTHFR – metabolic pathways and nutrigenomics

In humans, SNPs in the gene MTHFD1 increase the demand for betaine as a methyl-donor, thereby increasing the dietary requirement for choline. Another SNP in the gene PEMT prevents the activation of this gene by estrogen, thereby decreasing endogenous production of phosphatidylcholine (a source of choline) in the liver and increasing the dietary requirement for choline. [Choline: Critical Role During Fetal Development and Dietary Requirements in Adults. Ziesel]

But note that it is not so simple.  There are several forms of the MTHFD1 gene, for example MTHFD1L and MTHFD2. If MTHFD1 is commonly mutated, it may be a pseudogene.

Complexities interpreting SNPs

No simple test can unravel the intricacies of the human genome, and consumers should be suspicious of anyone claiming to be able to interpret measurements of tens of thousands of genes, with millions of genetic variations, some of which have effects on hundreds or thousands of the small molecules of metabolism (and perhaps on thousands of peptides or proteins involved in metabolism).

[A grand challenge for nutrigenomics.  Steven Zeisel. 2010.]

Mistakes in genomics data

Note that 23andme data, like any large genome scan, can have mistakes in it.  For example, the Enlis genomics blog found more than 500 likely mistakes in a sample of 23andme raw data!  (Enlis)

Furthermore, many important nutritional SNPs are not testing by 23andme.

Solution: Metabolic Testing
There is a genetic test for MTHFR variations. But there’s also a cheaper and more accurate way to test for whetherMTHFR variations are causing disease. We simply check the levels of homocysteine in the blood...In other words, the homocysteine levels determine our actions, not the MTHFR test results.[Cleveland Clinic]

Paleolithic Nutrition compared to Modern American Diet

From: Lieberman D. The Story of the Human Body: Evolution, Health, and Disease. Knopf Doubleday Publishing Group; 2013.

Scientific Statements Made by a Climate Change Skeptic

A recent op-ed in the Wall Street Journal concludes that "Climate Science Is Not Settled", contrary to activists' and scientists' claims that there is no longer even a debate.

The article, written by Steven Koonin, includes a number of interesting statements and is worth a read in its entirety. Unfortunately, responses to the article have not addressed many of his factual claims, so I wanted to list a few of them here.

Please feel free to comment or link to research that addresses or refutes these statements:

1) "For example, human additions to carbon dioxide in the atmosphere by the middle of the 21st century are expected to directly shift the atmosphere's natural greenhouse effect by only 1% to 2%. Since the climate system is highly variable on its own, that smallness sets a very high bar for confidently projecting the consequences of human influences."

2) "But feedbacks are uncertain. They depend on the details of processes such as evaporation and the flow of radiation through clouds. They cannot be determined confidently from the basic laws of physics and chemistry, so they must be verified by precise, detailed observations that are, in many cases, not yet available."

3) "Although the Earth's average surface temperature rose sharply by 0.9 degree Fahrenheit during the last quarter of the 20th century, it has increased much more slowly for the past 16 years, even as the human contribution to atmospheric carbon dioxide has risen by some 25%. This surprising fact demonstrates directly that natural influences and variability are powerful enough to counteract the present warming influence exerted by human activity."

4) "Even though the human influence on climate was much smaller in the past, the models do not account for the fact that the rate of global sea-level rise 70 years ago was as large as what we observe today—about one foot per century."

5) "[these model discrepancies] are not "minor" issues to be "cleaned up" by further research. Rather, they are deficiencies that erode confidence in the computer projections."

Can we stop megafires before they start?

The Pacific Northwest Research Station has a huge index of "Science Findings" written by science writers. Many of the articles champion fuel-reduction treatments (thinning) to alleviate the risk of extreme fires. But there is a controversy not evident in any USFS document: environmental groups such as the Pacific Rivers Council have questioned the impact of these treatments and whether it is even possible to stop extreme fires. It seems the "torching" and "crowning" indices the USFS uses to measure the effectiveness of fuel-reduction treatments are models that are not directly applicable to real forests. Further, it is clear the fuel-reduction alone will not provide long-term solutions without a return to natural fire frequencies or intensively-managed prescribed fire. Worst of all, thinning has most of the negative impacts associated with logging, such as soil disturbance and compaction, increased road building and use, and, ultimately, increased erosion. The controversial "Beschta Report", which makes these and other arguments, has been used by many to argue against the type of research presented in "Science Findings". The authors of this report, such as the Oregon hydrologist Jonathan Rhodes, have continued to argue that catastrophic wildfire is a natural disturbance than humans should not (and cannot) control. However, recent research from the Ponderosa Pine forests of Arizona and New Mexico does seem to indicate that thinning can decrease burn severity: Cram DS, Baker TT, Boren JC. Wildland fire effects in silviculturally treated vs. untreated stands of New Mexico and Arizona. 2006. Available from: http://www.treesearch.fs.fed.us/pubs/21792

The NRDC has also come out against thinning for biomass energy, based on their analysis of total carbon sequestration.

Antarctic Ice Increasing?

Most of this post deals with a paper by Turner, 2009.

My confusion started with a Watts Up With That post claiming that Antartica is actually gaining sea ice. As usual, a SkepticalScience page attempts a refutation, but to do so has to get into some complicated details.

So what is the trend?

from: http://nsidc.org/sotc/sea_ice.html

But Antartic sea ice is formed by a number of factors, including UV radiation from the hole in the Ozone layer, and land ice has been decreasing:"Ozone levels over Antarctica have dropped causing stratospheric cooling and increasing winds which lead to more areas of open water that can be frozen"

Apparently, land ice is more important in Antartica, and this had been decreasing. If the Ross Ice sheet collapsed, as it has numerous times in past interglacials, it would raise sea level by 21 feet.

Climate Change: Contrails

Aircraft Contrails Stoke Warming (Reuters, ):"Aircraft condensation trails criss-crossing the sky may be warming the planet on a normal day more than the carbon dioxide emitted by all planes since the Wright Brothers' first flight in 1903, according to a study in Nature Climate Change." [This is about 0.025 Watts per square meter, according to the IPCC (2007)]

Citation: Ulrike Burkhardt & Bernd Kärcher Global radiative forcing from contrail cirrus. Nature Climate Change 1, 54–58 (2011)

Image from Earth Observatory: "NASA scientists have found that cirrus clouds, formed by contrails from aircraft engine exhaust, are capable of increasing average surface temperatures enough to account for a warming trend in the United States that occurred between 1975 and 1994."
Citation: Minnis, Patrick, J. Kirk Ayers, Rabindra Palikonda, Dung Phan, 2004: Contrails, Cirrus Trends, and Climate. J. Climate, 17, 1671–1685.

"Trends in cirrus coverage and 300-hPa relative humidty (1971-19995) and estimated 1992 linear congtrail coverage. (a) Trends in cirrus coverage for all regions with more than 15yr of data. (b) Subset of (1) for all regions having trends sinifcant at the 90% confidence level according to Student's t test. (c) Estimated linear contrail coverage...Only observations taken from land stations and from ships are used for the land and ocean air traffic regions, respectively. (d) Trends in annual mean NCEP relative humidity at 300 hPa."

Citation: Minnis, Patrick, J. Kirk Ayers, Rabindra Palikonda, Dung Phan, 2004: Contrails, Cirrus Trends, and Climate. J. Climate, 17, 1671–1685.

"In response to the Minnis et al. conclusion, contrail Radiative Forcing (RF) was examined in two global climate modelling studies (Hansen et al., 2005; Ponater et al., 2005). Both studies concluded that the surface temperature response calculated by Minnis et al. (2004) is too large by one to two orders of magnitude. For the Minnis et al. result to be correct, the climate efficacy or climate sensitivity of contrail RF would need to be much greater than that of other larger RF terms, (e.g., CO2). Instead, contrail RF is found to have a smaller efficacy than an equivalent CO2 RF (Hansen et al., 2005; Ponater et al., 2005) (see Section 2.8.5.7), which is consistent with the general ineffectiveness of high clouds in influencing diurnal surface temperatures (Hansen et al., 1995, 2005). " (IPCC 2007)

Climate Crunch

Deconstructing Conclusions

During the winter of 2009-2010 I began investigating climate science, and since then have been reading in the field on-and-off. Again this last winter I have been reading way too much, trying to get to the bottom of various intricacies of the coupled earth-human system. Suffice to say, the Earth's climate is extremely complex, and every scientific sub-discipline has made its own peace with the devil in the details. Getting to the bottom of what scientists believe, and why, is no easy task, and after more than a year of research I have learned a huge amount about the Earth, but still am not definitively convinced about every aspect of climate change science.

This is as it should be. Science is complex and ever-evolving, and the Earth is a very, very complicated place. But provisional results and untested assumptions, although ever-present, make soft bedrock for climate policy. The truth is that we simply do not understand many of the key issues, such as feedbacks, in the climate system.

Many issues, such as divergence in tree-ring proxy records, don't by themselves discredit the theory of anthropogenic global warming, even if scientists can't explain everything. But they do begin to cast doubts. The issue of "hide the decline" probably falls into this category, because although some scientists chose to substitute instrument data for the misbehaving paleo data, the divergance can be explained. But is this explanation just hand-waving? How do we really know what happened hundreds or thousands of years ago? Obviously climate proxies may be complicated, idiosyncratic, and only reliable under certain conditions. It has been said that "trees are not thermometers," but this admission, even if carefully defined, can lead to increasing skepticism.

Unresolved Issues

Skeptic Science (SkS) has a great index of skeptic arguments, many of which continue to be problematic. They attempt to "refute" each argument, and they are the best source for good answers to most of these issues. But not every question can be answered definitively. Sometimes one question simply leads to three or four more. For example, they point out that warming is not due to the sun....but it is very, very, complicated. SkS explains why CO2 lags temperature in paleoclimate....but their response is not good system thinking, doesn't address the skeptic arguments about what the Vostok ice core means, and isn't especially convincing.

I've been researching climate change for over a year, and still am not close to understanding many of the major issues. What's worse, I can't find good evidence that the climate scientists understand all of the issues either! Much of science is dependent on good faith and trust, but at some point an explanation has to be convincing. Some theories (and I would put String Theory and Global Warming into this category) are too gnarly to be comprehended by mere mortals. They may be true, but I can't believe in what I don't understand.

The bottom line is that, if you really want to know,... its complicated. I'm officially revoking my previous conclusion, pending better explanations of the science. Maybe I'll have to wait to believe the models until they're proved true: until then I'll continue to entertain belief in multiple possibilities about this weird, beautiful world we live on.

More Paleoclimate Links:

NASA Climate Monitoring

NOAA paleoclimate

A History of Paleoclimatology

Top-Down or Bottom-Up?

A number of science controversies surrounding trophic cascades are well-presented in William Stolzenburg's book, "Where the Wild Things Were: Life Death, and Ecological Wreckage in a Land of Vanishing Predators". 2008. The book deals with the 20th century history of population ecology and the struggle to understand whether populations of animals and plants are controlled from the top by large predators or from the bottom by primary productivity. From Elton's realization of the pyramid of biomass on Spitzbergen to Hairston, Smith, and Slobodkin's Green World Hypothesis, to Paine's experimental verification of top-down control in starfish and mussel systems, the book covers the origin and development of such key concepts in ecology and conservation as keystone species and trophic cascades.

In addition to covering classic work such as Paine's starfish and mussel studies, the book also delves into controversies over killer whales and sea otter populations. While the latter are controversial because the results are relatively new, other controversies such as those over the rise and collapse of deer herds on the Kaibab plateau after the removal of top predators are controversial because the data are so old.

I wish the book had covered more of the controversy surrounding the Yellowstone wolves-grazing story in Wicker 2003 . The classic story of the wolves restoring Yellowstone's ecosystem to equilibrium should be interrogated because of differing interpretations of top-down (predator controlled) or bottom-up (hydrology-controlled) factors. For example, Wolf, Cooper, and Hobbs (2007) call much of Wicker's simplistic assumptions into question. And Meyer and Persico (2009) question Wolf, Cooper, and Hobbs' climate assumptions for the Holocene. The latter are both good papers, coming from different paradigms, all illustrating some of the difficulties for assigning "cause" and "effect" in dynamic and contingently evolving ecosystems.

Stolzenburg writes that "while the fall of the great terrestrial predators can be summed up as a casualty of the agricultural age, the subsequent collapse of their marine counterparts owes itself to the coming of the technological age." The work concludes with an excellent analysis of the conservation biology idea of linked conservation reserves, and the human opposition to acceptance of large wild animals. In the end, whatever the ecological story, the human social story will always get the last word.

Controversial Science Volumes

Sometimes silence speaks volumes about the state of science:

• An Analytical System of Clinical Nutrition. Dr. Schenker.

• Control of Colloid Stability through Zeta Potential.

• Cells, gels, engines of life.

• Maxwell's demon : entropy, information, computing / compiled by Harvey S. Leff and Andrew F. Rex