Ear To The Ground

Global Warming: There are reasonable, cost-effective steps that can slow the temperature rise, but they may be rendered moot by massive increases in CO2

First, some good news. Prior posts have noted repeatedly the key role that methane plays in global warming (the longterm trend in temperature, not seasonal or annual variations). Prior posts have also noted the role that particulates-aerosols play in global warming, and their adverse effect on human health.

Cutting the amounts of methane and "soot" that are poured into the atmospher would diminish warming by half a degree Celsius by 2050, researchers allege. That might buy time for the world to act, by slowing sea level rise, glacial melting, and other problems caused by rising temperatures. Targeting these agents of climate change would also improve air quality, potentially preventing up to 4.7 million premature deaths every year, the researchers believe. Compared to controlling CO2, these strategies are relatively inexpensive.

The researchers found that methane control was a key tool to slow global warming. Implementing controls already being used in various parts of the world would prevent atmospheric loading of methane from coal mines, livestock manure, landfills, and other sources noted in prior posts. Putting filters on cars that burn diesel, for example, could trap the soot which absorbs sunlight and heat the atmosphere. Soot also, as noted previously, darkens snow and glaciers, which hasten their melting. Critics of the latter aspect to the strategy note that some sources of soot also give off particles that reflect sunlight, cooling the planet. Clearly some critical assessment needs to be done.

The report can be found at http://www.sciencemag.org/content/335/6065/183.abstract.

Now the bad news. The increasing use of coal for power generation in China and India, and for that matter across Asia, is likely to lead to a large increase in CO2 emissions. Unfortunately neither solar nor wind will offer affordable electricity on a large enough scale to slow this expansion of coal-fired generation, even with the potential significant increases in efficiency noted in prior posts. It is also unlikely that natural gas will supplant coal in this region.

The International Energy Agency has compared the likely result of this massive increase in coal-fired generation with the goal often put forth of holding global warming to below 2 degrees C this century. Given the plants "in the pipeline" it is likely that enough generating capacity will be online by 2017, believes the IEA, that this goal will not be met.

A discussion of this issue can be found at http://www.economist.com/node/21548237.

California Superior Court blocks regional GHG regulations for failing to undertake CEQA review

In Nov. 2010 the California Building Industry Association (CBIA) filed suit against the Bay Area Air Quality Management District’s (BAAQMD) CEQA Guidelines re GHG emissions. Among other requirements, environmental evaluations were required if a project was to be built within 1,000 feet of a freeway, oil refinery,or other air pollution source. Developments producing 1,100 metric tons of GHG emissions per year would have to draft environmental reports as part of the approval process. [In California, the California Environmental Quality Act (CEQA) is substantive law, not merely procedural law, unlike NEPA.] The Guidelines had been expected to be a model for other air quality management districts in California.

On Jan. 16, 2012, the Alameda County Superior Court struck down the Guidelines on the grounds that the Guidelines themselves must first undergo a CEQA review. Although the Court has not yet issued a written order, it is expected to set aside the Guidelines unless and until BAAQMD conducts CEQA review. The Court noted that the BAAQMD should have reviewed the environmental impact of the Guidelines, including their impact on future growth and transportation patterns. The CIBA had, among other bases, claimed that the Guidelines would exacerbate urban sprawl, thus hindering compliance with AB 32, California's law to reduce GHG emissions to 1990 levels by 2020.

The BAAQMD has not yet announced if it will appeal. [Expect an appeal.]

The case is California Building Industry Assoc. v. Bay Area Air Quality Management District, Alameda County Superior Court, Docket No. RG10548693.

Air pollution may be causing mega-cyclones striking India & the Middle East

It is well known that warm sea-surface temperatures can boost the intensity of hurricanes (known in the Indian Ocean as cyclones).  For many decades water in the Arabian Sea has been warm, which should enhance the strength of cyclones.  However, regional winds in the upper and lower atmosphere tend to blow briskly in opposing directions, resulting in vertical wind shear [see http://en.wikipedia.org/wiki/Wind_shear].  This phenomenon can have a major impact on the strength of storms [see, for example, http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/svr/comp/wind/home.rxml].  Thus, mega-cyclones were relatively rare, until recently.

Researchers analyzed every regional tropical cyclone for the last 30 years.  None had occurred during the monsoon season, and before 1998, cyclones in the months before and after that rainy season seldom reached wind speeds exceeding about 80 kph. But since 1998, five large storms reached wind speeds double the "norm" (sometimes exceeding 185 kph).  The researchers found that in premonsoon months there had been a slow decrease in the average vertical wind shear, from 11 meters per second to 8 meters per second; they concluded that the lower speed appeared to represent some type of threshold.  At the lower range, mega-cyclones were possible.

The researchers ultimately linked the steady decrease in vertical wind shear in cyclone seasons with a 3-kilometer-thick brown cloud of soot and other pollutant particles (e.g., aerosols [see http://en.wikipedia.org/wiki/Aerosol]) in the region’s lower atmosphere.  This pollution has increased sixfold in 80 years, and now filters roughly 10% of sunlight, preventing it from reaching the sea surface.  Computer analyses indicated that the pollution cloud’s cooling effect on the ocean below has slowed wind speeds in the atmosphere, and allowed storm intensities to increase.

Critics could not unreasonably focus on the modest data set of mega-cyclones that were available for analysis.  However, the researchers appear to have identified a reasonable causal relationship.

This analysis demonstrates a fascinating interplay between global warming and air quality.

The report can be found at http://www.nature.com/nature/journal/v479/n7371/full/nature10552.html.

For more information on related topics, see http://www.agu.org/pubs/crossref/2005/2005GL023125.shtml and http://www.aoml.noaa.gov/hrd/tcfaq/tcfaqHED.html.

Statistics, a weak link in environmental, medical, & toxicological studies?

Statistics are used throughout science both by those proposing a conclusion and those opposed to said conclusion.

Statistics form the basis for a wide variety of claims made about environmental, medical, and toxicological matters.  I would even go so far as to note that they are often utilized by charlatans to give the illusion of analysis and certainty, when no such conclusions are justified.

An interesting assessment and discussion of the problem one often encounters with statistics used in various studies can be found at http://www.sciencenews.org/view/feature/id/57091/title/Odds_Are,_Its_Wrong.  I commend it to your review.  A skeptical attitude toward any expert needs to be an attorney's SOP, especially in this age of Daubert.  (See http://en.wikipedia.org/wiki/Daubert_standard for an overview of Daubert.)

Another reason to control erosion and nutrient runoff -- Cholera

Numerous prior posts have followed the growing understanding of what factors drive the Gulf of Mexico dead zone.  It pretty much comes down to nutrient runoff into the Mississippi River and its tributaries (e.g., sewage, feedlots, agricultural fertilizers).  Now, another association of such nutrient additions to bays and deltas has been found, cholera outbreaks.

Cholera is caused by a bacterium, Vibrio cholerae.  The accepted wisdow is that it is introduced into an environment by human activities (e.g., fecal matter not subject to sewage treatment).  Among other places, Vibrio lives in water near river mouths, waxing and waning in cycles based on blooms of plankton; the plankton are eaten by tiny crustaceans to whose shells Vibrio attaches.  Since without more warmer ocean surface waters suppress plankton growth, researchers have assumed that cholera outbreaks would decrease with global warming.  To steal a line from Porgy & Bess, it ain't necessarily so (http://www.youtube.com/watch?v=pLLoNi4qHPg).

Plankton growth is driven by two factors.  One is the phytoplankton blooming produced by the upwelling of cold, nutrient-rich deep ocean waters.  The second is produced by nutrient-rich freshwater from the aforenoted sources producing plankton blooms when discharged into river deltas.  At least so far, this factor clearly overwhelms whatever "control" results from global warming.

Thus, nutrient runoff from freshwater rivers into bays and deltas not only poses a risk by triggering dead zones, but by producing plankton blooms it also increases the presence of Vibrio and its potential for causing cholera epidemics.

A report on this phenomenon in the Bay of Bengal can be found at http://www.ajtmh.org/content/85/2/303.abstract.   

What is the source of the oceans' production of N2O, a potent GHG?

The oceans emit an estimated 30% of the nitrous oxide (N2O) entering the atmosphere.  Nitrous oxide gives rise to NO (nitric oxide) when it reacts with oxygen atoms, and this NO in turn reacts with ozone.  As a result, N2O is the main naturally occurring "regulator" of stratopheric ozone.  N2O is also a potent GHG; it has 310-times the heat-trapping potential of CO2.  [In soil, N2O is produced during the microbial processes of nitrification and denitrification.]

Yet the oceanic source of N2O has puzzled researchers for years.  Bacteria, long the leading candidate, can generate N2O, but the seas do not appear (it is believed) to contain enough bacteria to account for all of the N2O that the marine world has been producing.  Now researchers offer an alternative view, archaea (see http://en.wikipedia.org/wiki/Archaea), which were once thought to be a type of bacteria.  Despite their vast numbers, the presence of marine archaea only came to light in 1992.

Researchers have found that archaea transform ammonia into N2O (at least in the lab).  Since there is no shortage of ammonia in the oceans, the researchers believe that they have found a likely key to the "mystery."

The study can be found at http://www.sciencemag.org/content/early/2011/07/27/science.1208239.abstract.

U.S. Supreme Court finds that statutory law of CAA displaces Federal common law and state tort law on issue of GHG emissions

Several States, a city, and land trusts filed federal common law public nuisance claims against various power companies; they requested that the court set CO2 emission limits. 

In American Electric Power Co. et al v. Connecticut et al, 2011 U.S. LEXIS 4565 (6/20/11), the U.S. Supreme Court addressed the issue.  The Court found that Clean Air Act (CAA) and the EPA actions authorized by the CAA displaced any federal common law right to seek the relief sought, especially given that the CAA "spoke directly" to such emissions.  42 U.S.C. Section 7411.  Section 7411 directed the EPA to list categories of air pollution and establish emission standards.  GHG emisisons were air pollutants within the meaning of 42 U.S.C. Section 7602(g).  If EPA fails to set appropriate standards, the CAA provides a mechanism for petitioning EPA to set such standards.

The Court also noted that EPA was doing so for greenhouse gas emissions from fossil-fuel fired power plants.  Further, the CAA provides a means to seek limits on the emissions, which is the same relief the plaintiffs sought by invoking federal common law.  Further, the CAA allows for trade-offs and for a sophisticated differentiation between sources, impacts, etc.  Because Congress has delegated to EPA the decision whether and how to regulate carbon-dioxide emissions from power plants, the delegation displaced federal common law.  As such, there was a conflict between what plaintiffs sought in terms of relief from the judicial system and the statutory scheme Congress enacted.

The Court found that it was error for the 2nd Circuit to find that federal judges could set limits on greenhouse gas emissions in face of a law empowering the EPA to set the same limits, subject to judicial review only to ensure against arbitrary, capricious, or unlawful action under 42 U.S.C. Section 7607(d)(9).

Solar cycle is abating impact of GHG emissions, Part 2

A recent posting noted that because the Sun is at a solar minimum, the impact of GHG increases in the atmosphere have been less than would otherwise be anticipated.  Now, a new report suggests that the Sun is entering an unanticipated, a potentially prolonged period of solar minimum.  Some will take a "what, me worry?" attitude in light of this potential "blessing"; others will see it as an opportunity to take corrective action without suffering the full consequences for past activities.

To say that understanding what drives the so-called "eleven year" solar cycle has a ways to go is a statement of the obvious.  What we do know is that a weaker solar cycle is accompanied by a slightly dimmer sun, which changes the average temperature on Earth.  As noted in the prior post, solar cycles are a variable lot, with consistency not being their strong point.  For example, the sun’s brightness did not hit an all-time low during the past solar minimum, even though the sun was unusually quiet.

Nonetheless, the decline in solar brightness from 2002 to 2008 as solar activity dwindled probably countered the warming on Earth that would otherwise have occurred due to GHG increases over that period.  When the Sun does pick up, we can expect that the impact of GHG emissions will be more severe than it now appears to be.

An interesting thesis on what drive's solar cycles can be found at http://www.nature.com/nature/journal/v471/n7336/full/nature09786.html.  However, it should be noted that it is controversial, with critics noting that the speed of the meridional flow, a key factor in the theory, being exactly the opposite to that required by the thesis.

 

Human impacts on the climate preceded the dawn of the petroleum age

Prior posts, occasionally with tongue planted firmly in cheek, have noted that human impact on carbon loading in the atmosphere goes back to well before the industrial era.

A recent assessment has calculated that over the eight millennia before 1850, clearing land (for both hunting and for farming) removed trees that had stored or would store CO2, adding approximately 350 billion metric tons (1 mt = 1,000 kg or 2204.62 lbs) of carbon into the atmosphere by 1850. For purposes of comparison, it should be noted that it has been estimated that humans have added 440 billion metric tons of carbon since 1850, mostly from burning fossil fuels.

As population grew over the 8 millennia before 1850, the Earth's forests were converted to other uses. However, it is not a linear relationship. With irrigation, fertilizer, multicropping, and new tools, crop yields increased and the per capita rate of land use fell.

This new estimate (350 billion metric tons) is much larger than several other estimates published within the last year, and reflects assumptions regarding how carbon is stored in the soil when forests are replaced by grasslands. Critics have noted that the chemical composition of carbon dioxide bubbles in ice cores do not reflect changes that might be expected if forests were removed as hypothecated. In response, researchers have stated that rapidly expanding peatlands could counter-balance some of the impacts.

Other researchers have undertaken more regional studies, and have found that land use often varies significantly. For example, the use of wet-grown rice systems in China required fewer acres to feed people than the cereal grains grown in Mesopotamia. Because of population distribution across the globe, preindustrial emissions goes up for countries like India and China, which emitted a lot of carbon millennia ago. In contrast, North America remained relatively pristine forests until the last couple of hundred years. Thus, the balance between pre-1850 emissions and post-1850 emissions is more complex and nuanced.

The study can be found at http://hol.sagepub.com/content/early/2010/12/24/0959683610386983.short?rss=1&ssource=mfr.

How does one assess the amount of carbon stored in a forest? Lidar

Calibrating measurements from study teams on the ground with the results of a readouts from "light detection and ranging" instrumentation (LIDAR), Arbonaut, a Finnish natural resources management firm, has created the technology to product 3-dimensional images of the trees in a forest, which can be used to estimate the amount of carbon stored.  The information can then be used to verify commitments to prevent forest degradation and also for carbon-trading schemes.  A nice overview of the technique can be found at http://www.economist.com/node/18741402?story_id=18741402.