Thursday, February 26, 2015

The President Vetoes Keystone XL Pipeline Bill

On Tuesday President Obama vetoed a bill from congress that would have authorized construction of the final segment of the Keystone XL pipeline and taken the authority from the U.S. Department of State. However, with the President’s veto the Keystone XL pipeline appears to remain permanently in limbo with the state department.

There is currently a pipeline Keystone I that runs east from Hardesty Saskatchewan to Manitoba and then south through the Dakotas to Steel City, Nebraska. It is a less direct route and is a lower volume pipeline than the proposed Keystone XL.The Keystone XL would replace Keystone I with a  a new and better pipeline. Keystone I is old and this would be an upgrade to the oil transport infrastructure. Keystone II runs from Steel City to Cushing, Oklahoma at the Oklahoma storage facilities. Keystone III running from the Cushing Oklahoma to the Nederland, Texas began delivering crude oil from Cushing, OK, to the oil refineries in Texas on Wednesday, January 22, 2014. The Gulf Coast Project, Keystone III, did not require a Presidential Permit because it does not cross an international border..

On January 31, 2014, the U.S. Department of State released the Final Supplemental Environmental Impact Statement for the Keystone XL Pipeline. The executive summary states that Keystone XL is “unlikely to significantly impact the rate of extraction in the oil sands or the continued demand for heavy crude oil at refineries in the United States based on expected oil prices, oil-sands supply costs, transport costs and supply-demand scenarios.” In other words, no matter what action the Administration does the oil sands are not staying in the ground in Canada. There is world demand for heavy crude oil and it will be met. The Texas refineries are optimized for heavy crude either from South America or Canada. The crude oil will come by pipeline, boat, truck or rail road. As Marcia McNutt, the editor in chief of the AAAS journal Science stated in a recent editorial moving the Canadian crude by pipeline is the least environmentally damaging and safest method of transporting oil.

The Department of State opened a second 30 day comment period on February 5, 2014 then in April the administration announced that they would be delaying the decision until after the Nebraska Supreme Court decided the case which happened last month. Citing uncertainty from a February court decision that struck down a Nebraska state law (LB1161) allowing the Governor to approve the route in Nebraska the Department of State comment period was kept open. However, on Friday, January 9, 2015 the Nebraska State Supreme Court ruled that the measure passed in 2012 “must stand by default.” The law under question was Nebraska law LB 1161 that Governor Heineman used to sign the January 2013 recommendation to the U.S. Department of State for a Presidential Permit for the Keystone XL pipeline to cross the international boarder.

Back on May 4th 2012 TransCanada Corporation made a new application for a Presidential Permit to construct and operate the Keystone XL Pipeline after the Department of State rejected their original 2008 application in January 2012. At the time, the Department of State was under a deadline imposed by Congress and rejected the application because of inadequate time to determine the environmental impact of the proposed pipeline.

TransCanada Corporation turned around and on May 4th 2012 announced a new application for a Presidential Permit to build the northern most section of the Keystone XL pipeline (Phase IV) from the Canadian Border from where Saskatchewan meets Montana using a route that would cross South Dakota and a new route to cross Nebraska and meet up with the Keystone Phase II which runs from Steel City, Nebraska to Cushing, Oklahoma. On January 22, 2013 Governor Heineman of Nebraska signed the recommendation to the U.S. Department of State for a Presidential Permit for the Keystone XL pipeline to cross the international border after the Nebraska state regulators recommended approval of the revised route selected (with their guidance) for the Keystone XL Pipeline.


Monday, February 23, 2015

NASA Probe to Improve Climate and Weather Forecasting

from NASA
On January 31, 2015 NASA successfully launched the SMAP (Soil Moisture Active Passive) mission satellite.  The SMAP mission will provide global measurements of soil moisture and its freeze/thaw cycle from a near-polar sun-synchronous orbit. The plan is for SMAP to measure soil moisture every 2-3 days over at least a three year mission.

The SMAP mission will provide global mapping and monitoring of landscape freeze/thaw cycle and surface soil moisture content. The data will be used to model and estimate the earth carbon/ carbon dioxide fluxes and underlying environmental controls. Scientists hope that these observations will allow them to link together the terrestrial water, energy and carbon cycle processes and identify why the climate models have failed to predict the last 15 years of near stable global temperatures. Scientists hope to use this and other global data to identify the functioning of the “missing carbon sink” that has slowed the predicted rise in global temperatures. NASA hopes that SMAP will bring us some of the data we need to better understand our planet and predict its future. Though, the most immediate benefit will be drought prediction.

SMAP will accomplish its mission by measuring how much water is contained in the top layer of soil and identifying when the ground is frozen. This is accomplished using an instrument that combines an L-band radar and an L-band radiometer that both share a 6 meter in diameter aperture reflector. The reflector will rotate to scan a 621 mile wide swath of earth on each orbital pass of the observatory. The radiometer provides “passive” measurements of the microwave emissions of the upper soil. The radar makes the “active” back scatter measurements of the surface. Thus, the name of the mission- Soil Moisture Active Passive.

The ground processing systems run by the NASA Jet Propulsion Laboratory and the Goddard Space Flight Center will combine the data sets. Combining the active and passive datasets increases the resolution and accuracy of the data. Together the instruments will be able to measure the moisture in the top two inches of soil to a spacial resolution of under two miles.

The SMAP mission will also collect data on the frozen/thawed state of the soil. This information is important to understand the length of the plant growing season and will increase our understanding the contribution of the boreal forest to the global carbon balance and contribute to a better understanding of droughts and climate.

A high-resolution, space-based measurement of soil moisture is a new capability. Scientists will be able to better predict natural hazards of extreme weather, climate change, floods and droughts, and help reduce uncertainties and unknowns that now exist in our understanding of Earth's water, energy and carbon cycles. Several of the data gathering techniques grew out of previous NASA missions of this century including the Aquarius project and the cancelled Hydros project.

The microwave portion of the electromagnetic spectrum (wavelengths from a few centimeters to a meter) is used to estimate the surface soil moisture. Passive microwave sensors measure the natural thermal emission emanating from the soil surface. The intensity of this radiation depends on the dielectric properties and temperature of the target medium, which for the SMAP mission is the surface soil layer and is a function of the amount of moisture present. The low microwave frequencies used offer additional advantages; the atmosphere is almost transparent in that wavelength so weather does not impact the sensing, transmission of the data from the soil is also possible through sparse to moderate vegetation water content, and the microwaves measurements are not impacted by daylight to allow for 24 hour observations.


The SMAP mission will map the entire globe every two to three days for at least three years and provide the most accurate and highest-resolution maps of soil moisture ever obtained. The spacecraft's final circular polar orbit will be 426 miles (685 kilometers), at an inclination of 98.1 degrees. The spacecraft will orbit Earth once every 98.5 minutes and repeat the same ground track every eight days.

Weather forecasting, accurate modeling and forecast of climate variability and change, planning and predicting agricultural productivity, effective water resources management, drought prediction, flood area mapping, and ecosystem health monitoring all require information on the status of soil moisture. Soil moisture affects plant growth and agricultural productivity, especially during times of drought or water shortages. This can improve our ability to monitor and forecast agricultural productivity and allow for a famine early warning in the most food insecure regions of the earth.

Thursday, February 19, 2015

No Water from the Well it Could be Frozen Pipes

my well in the snow
I live in the Rural Crescent in Northern Virginia, a lovely place with moderate four season weather. Though we have snow, it usually doesn’t stay on the ground too long because it is rare to have more than a week of freezing weather. This winter I watched in wonder as my brothers sent me pictures of how high the snow is in Boston. My older brother is several inches more than six feet tall and the last picture he sent, the snow was above his head.

We bought our home in Virginia about 8 years ago when we retired. Unfortunately, because of the usually mild winters, our house was built with a Jack and Jill bathroom partially above the garage. The year we bought the house I insulated the heck out the garage and the dormer above it, replaced the garage door with an insulated door, and wrapped the pipes in foam. However on Saturday night while my husband and I were enjoying a pot of goulash, fresh baked bread (thanks Deborah for your bread recipe) and a great bottle of Cabernet Sauvignon a winter storm blew this way with temperatures dropping into the single digits and a wind of 50 miles an hour. With the wind chill, I am told it “felt like” -14 degrees. In the morning there was nothing coming out of the sink and tub in that Jack and Jill bathroom. The pipes in one of the sinks and tub in the Jack and Jill froze overnight. If on a very cold day you turn on a faucet and either get nothing or just a trickle comes out, suspect a frozen pipe. If your well supply line or the water main is not frozen, you may have water in part of the house.

The likely pipes to freeze are against exterior walls of the home, or are exposed to the cold, like outdoor hose bibs, and water supply pipes in unheated interior areas like basements and crawl spaces, attics, garages, or kitchen cabinets. Pipes that run against exterior walls that have little or no insulation are also subject to freezing. In sub-zero weather wells with separate well houses can freeze. Keeping the temperature in a well house above freezing will prevent this. Sometime in the middle of the night as the wind howled, I thought about that bathroom, discarding my first thought of letting the water drip to keep the pipes flowing. Letting the water run can work, but can also create other problems. Though if you are on city water and sewer then a low flow can keep the pipes from freezing, it can overwhelm a septic system or worse a dribble into the septic could have frozen. Drain pipes are not insulated and can freeze.

When I got up I checked the kitchen, bathrooms and laundry sink and all but the Jack and Jill bathroom were working fine. I made sure that the toilets could flush and thought about my options and consulted with my friend Ron Jones from Chantilly Plumbing while I had coffee. The well supply line runs under the garage slab. At that corner of the house where the well supply line connects to the pressure tank the basement is more than 8 feet below ground and the well line enters the basement mid wall-several feet below ground and significantly below the frost line here. The main water supply to the house was fine, only a small section of piping was frozen.

I spend a lot of time and effort conserving energy so it was fairly difficult for me to do what I had to do next. I pumped up the heat in the house to 70 degrees from 65. I opened the cabinet under the sink in the Jack and Jill, and went down to the cellar to get the two old ceramic heating cubes we had ($39 but great). I put one cube in the garage and the second one upstairs facing the sink. I opened the faucet a touch in the sink and tub. I needed to get the pipes warm enough for the ice to melt. The house has plastic piping that is considerably more tolerant of freezing than copper pipes. There is a real shot that a plastic pipe can freeze without bursting if all the connections and elbows are sound.
The little heater that saved the day in my garage. Yes, I finished my garage.


However, the only way you will know if the pipe has burst (other than ripping out the ceiling) is to defrost the pipe and run the water and look for the leak. Water expands when it freezes applying force in all directions, but damage done by the ice occurs typically at elbows and joints where the force is constrained. Some plumbers believe that toilet valves and pressure tanks (used in homes with private wells) can allow a plumbing system to absorb the increased pressure and reduce the likelihood of a burst pipe. The open faucets in the Jack and Jill bathroom were intended to offer another source of relief of pressure as the pipes defrosted and allow the water to flow as the pipe defrosted.

I did not run the water during the coldest part of the night before. While running water may prevent the water supply pipes from freezing, in the coldest weather the slowly running water might cause the drain pipe to the septic system to freeze and block the flow or even burst. I would much rather deal with a frozen possibly burst pipe in the garage of fresh water from the well than a burst septic pipe or a backed up septic system from a flooded tank. Burst supply pipe- much nicer to clean up. So, to make sure that the drain line to my septic tank was clear, I ran the hot water a while in the working bathroom and kitchen. Then to flush the line and not totally waste water I put up a load of laundry in hot water.
My septic tanks in the snow
Okay, what next. I needed to wait. Patience. It was late Sunday afternoon by this time ( yeah, yeah, yeah we stayed up too late Saturday night drinking that fabulous bottle of wine), the wind was still whipping around at 30 miles an hour and the temperature never rose above the mid-teens. So Sunday turned to Monday. The wind died down the thermometer we put in the garage was climbing into the forties. Finally, I heard it -water flowing. Lucky me it was the sink and tub and not coming out of the ceiling. I took a bath in the Jack and Jill and then checked the ceiling of the garage-nothing. Yeah, lucky me.

I was lucky this time, but repeatedly freezing and thawing a plastic pipe can cause it to stress fracture. So I need a new and improved plan for freezing weather. The obvious answer is the next cold front (due in today) I turn on the heating cube in the garage open the cabinet below the sink and run the extra heater overnight. From now on when the weather is forecast for the single digits overnight that is the plan. For those of you with separate well houses that are far more likely to freeze overnight and no longer have access to the 100 watt bulb that kept the old below grade well house warm enough during  New England winters, there are Thermocubes, heating tape and heating pads.

Monday, February 16, 2015

The CarbFix Pilot Project and Carbon in the Atmosphere

The capture and storage of carbon dioxide and other greenhouse gases in deep geologic formations has been part of every proposed plan to reduce greenhouse gases in our atmosphere. Carbon capture is really three activities: Gathering or capturing of CO2 from point sources (power plants, industrial plants, and refineries), transporting the captured CO2 to a geological storage site, and injecting the CO2 into the ground for permanent storage and monitoring the site for eternity. The standard approach to geologic storage of CO2 is to capture and separate CO2 and then inject the CO2 into geologic formations at depths greater than 2,600 feet. According to the researchers efficient underground storage of CO2 requires that it be in the supercritical (liquid) phase to minimize required storage volume.

In order for CO2 to remain in a supercritical phase, the pressure in the storage reservoir must be greater than about 68 atmospheres and at temperatures above 31.1°C. (Sminchak et al., 2001). These conditions require that the CO2 be injected at high pressures, which can only be achieved at depths greater than 2,600 feet below the earth’s surface. Unfortunately at this depth CO2 is both supercritical and buoyant. As a result, the buoyant CO2 may migrate back to the shallow subsurface and surface. Keeping the CO2 within the formation forever is the challenge. The effectiveness of geologic storage of CO2 depends on the retention time, reservoir stability, and the risk of leakage which is a huge technical hurdle. Long term the geologic formation may allow the buoyant CO2 to bubble up and leak out of the rocks, reducing the effectiveness of the scheme and potentially contaminating shallow groundwater. Injection sites would have to be monitored for decades if not centuries.
Image from J.M. Mather presentation


Another approach for the permanent storage of CO2 is the mineralization of CO2 into stable carbonate minerals such as calcite (CaCO3), dolomite (CaMg (CO3)2), magnesite (MgCO3) and siderite (FeCO3) that would lock up the CO2 in the rocks themselves. It was proposed that this mineralization could be accomplished in-situ in basaltic (silicate) rocks using CO2 fully dissolved in water. Mineral carbonation can theoretically occur in many kinds of rock, but often it is extremely slow. The CarbFix approach accelerates the process by injecting into basalt, a very reactive rock. Basaltic rock is young rock forming where basaltic magma rises from deep within the earth to form new crust. There are many places on earth where this is occurring: the Mid-Atlantic Ridge Mid-Atlantic Ridge, the Pacific Northwest and Iceland are three. Small scale testing of the concept showed that CO2 could be locked in rocks and currently the Big Sky Carbon Sequestration Partnership project in Washington and CarbFix project in Iceland are testing the concept.

Big Sky Carbon Sequestration Partnership relies on existing technologies and is a small scale demonstration of concept project. CarbFix is a pilot project designed to inject 2.200 tons of CO2 per year in Iceland to test the feasibility of in situ mineral carbonation in basaltic rocks in the real world. At the test site in Hellisheidi in the southwest portion of Iceland, the CarbFix project has been in operation for several years. The project was created to optimize in situ mineral carbonation in basalt. The pilot consists of a CO2 pilot gas separation plant, CO2 injection pilot test, laboratory-based experiments, confirmation testing and numerical modeling.
Image from J.M. Mather presentation


The CarbFix group developed a new injection system was used to mix the captured and separated CO2 with groundwater in a ratio of one pound of CO2 per 28.5 pounds of groundwater. The injection system delivers the water and CO2 mixture 1,600 feet beneath the surface into the target storage formation. The scientists tagged the CO2 collected with radiocarbon (14C) by adding 14C to the groundwater so that they track and document the mineralization process in basaltic rocks in Icelandic geothermal fields and differentiate between the natural mineral formation and the in-situ CO2 fixing.

Now the scientists have taken a series of core samples to examine the extent of in-situ mineralization of the injected CO2. The project’s implications for the fight against global warming are unknown, though basaltic bedrock susceptive of CO2 injections are widely found on the planet, the costs of capturing the CO2, transporting and mixing with vast quantities of water and injecting into the rock are huge. According to recent Department of Energy estimates, the United States and portions of Canada have enough potential capacity in geologic formations to store as much as 900 years of CO2 emissions (at whatever level of emission they used to estimate that).

Capturing and transporting CO2 from industrial plants is technologically possible but is currently prohibitively expensive, and the additional cost for the CO2 fixation is estimated at $17/ton. World emissions were about 38 billion tons in 2012. Nonetheless, the technology may lead somewhere or be useful in our understanding of our planet or the survival of Homo sapiens on the planet.

Thursday, February 12, 2015

Micro Pollutants from Septic Systems

Traces of pharmaceuticals, hormones and personal care products associated with everyday life in the United States are finding their way into groundwater through septic systems and these micro pollutants can find their way into drinking water supplies. This is exactly what is happening in New York and New England, according a recently published study by the U.S. Geological Survey (USGS). The paper, “Concentrations of hormones, pharmaceuticals and other micropollutants in groundwater affected by septic systems in New England and New York” by Patrick J. Phillips, Irene J. Fisher, et. al. details the findings at two different locations that were studied, one in New England and the other on Fire Island in New York.

This study was the first to be published that used a new highly sensitive analytical method developed by the USGS National Water Quality Laboratory that identifies more than 100 pharmaceuticals, pharmaceutical degradates and related contaminants in trace concentrations. This method has detection limits for many compounds in the low nanogram/liter (that is about one thousandth of a part per billion) range, and significantly advances the abilities of the USGS to assess the presence and concentrations of pharmaceuticals in the environment.

The two sites were chosen because high nitrate concentrations in groundwater samples down gradient of these septic systems begged the question of what other chemicals might also be present. Though nitrate can contaminate groundwater from fertilizer use; leaking from septic tanks, sewage and erosion of natural deposits, increased nitrate concentration is usually a sign of improperly operated or failing septic systems and is an indication that septic system waste is contaminating groundwater. The MCL for nitrate is 10 mg/L and easily tested for. The NO3 dissolves and moves easily through soil. Due to plant uptake, there is a seasonal variation, and testing in the spring will usually produce the highest levels of nitrate. Elevated nitrate usually indicates contamination from septic tanks as it did here. What is important about this study is that the USGS scientists also found traces of other chemicals in the groundwater and demonstrated that these pharmaceuticals and related contaminants do not just disappear, but are spreading through groundwater into the environment.

The USGS scientists looking for micropollutants in groundwater collected samples down gradient of septic systems. The scientists tested for items such as pharmaceuticals, personal care products, and plasticizer compounds used in plastics. In New England a series of existing down gradient groundwater wells and wells installed to monitor the leach field were used to collect samples to measure the effect of a single large septic system that serves a nursing home with 65 patient beds and staff. Samples were collected from below the septic system leach field in addition to samples from wells down gradient of the septic system. The USGS scientists found numerous prescription drugs in the groundwater samples, such as anesthetics; a muscle relaxant; an antifungal; an antiepileptic; an antibiotic; a sleep aid; and also a floor cleaner. Total concentrations for these compounds generally ranged from 1 to over 20μg/L in the groundwater samples. High tris(2-butoxyethyl phosphate) plasticizer concentrations in wells beneath and down gradient of the leach beds (>20μg/L) were thought to reflect the presence of this compound in cleaning agents used at the nursing home.

On Fire Island in New York, groundwater samples were collected from an area of dense summer populations (5 dwellings/acre). The Fire Island septic systems have minimal treatment of wastewater (they are essentially tank only systems) before mixing with shallow groundwater that moves towards a large, estuary where a decline in fisheries and shellfish along with a higher ratio of female-to-male fish had been reported.

Shallow groundwater samples collected along the beach of this estuary down gradient of the septic systems were found to have hormones; detergent degradation products; galaxolide, a fragrance found in various products; insect repellent; sunscreen additives; floor cleaner; and two pharmaceuticals (lidocaine, a local anesthetic; and carbamazepine, an anti-convulsant and mood stabilizing drug). The highest micropollutant concentrations for the Fire Island study found in one of the shoreline wells that had personal care/domestic use, pharmaceutical, and plasticizer concentrations ranging from 0.4 to 5.7μg/L.

Most micropollutant concentrations increased with increasing total nitrogen concentrations for the shoreline well samples. The USGS scientists draw narrow conclusions stating that “these findings suggest that septic systems serving institutional settings and densely populated areas in coastal settings may be locally important sources of micropollutants to adjacent aquifer and marine systems.” The potential for measurable groundwater contamination and environmental impact from septic systems clearly places these systems within the expanded EPA definition of “navigable waters of the United States” and makes regulatory action possible if not likely.

Septic systems are common in rural areas and those lacking connection to larger scale sewage treatment plants. Septic systems consist of holding tank where raw sewage collects and separates into a sludge (solid) and liquid effluent. The liquid effluent either leaches directly into the surrounding soil or goes into a leach field for final treatment by the soil. The liquid effluent from septic systems ultimately moves into the groundwater. There are also alternative septic systems that have a secondary treatment system (be it a secondary aerobic tank or other treatment media) to remove pollutants. Though more than 30% of households are served by onsite septic systems, a significant numbers are quite old and many are not properly operated or maintained. Proper maintenance of septic systems (both traditional and alternative) is essential for protection of public health and local water resources. With new more sensitive testing methods it is possible to measure the impact of these systems on groundwater supplies and the environment. However, a simple annual nitrate measurement would indicate a problem and can be used as a proxy for the more expensive tests.


The article discussed:
Concentrations of hormones, pharmaceuticals and other micropollutants in groundwater affected by septic systems in New England and New York, Science of The Total Environment, Volume 512-513, Issue null, Pages 43-54,P.J. Phillips, C. Schubert, D. Argue, I. Fisher, E.T. Furlong, W. Foreman, J. Gray, A. Chalmers.

Monday, February 9, 2015

Meat, Health and the Environment

A young person I know has recently become a vegetarian and my step sister and her spouse have become vegans. So, I have been thinking about many of the aspects of food sustainability, and the many different styles of being a “vegetarian.” These days a diet limited to only plant based food is called veganism. Vegetarians can include dairy products, eggs and seafood. The most basic definition of vegetarian is someone who eats anything but land based meat.

According to Dr. Vaclav Smil formerly of the University of Manitoba and author of Should We Eat Meat? the various permutations of vegetarianism represent less than 4% of all western societies and the long-term adherence to a vegetarian diet is less than 1%. (My step sister supplements her vegan at home diet with the occasional hamburger which turns out to be probably an excellent diet.) The reasons someone becomes a vegetarian vary from moral to those who become vegetarians for more pragmatic reasons to lose weight, reduce blood pressure, cholesterol or reduce cancer risk.

According to Dr. Smil’s book several large scale national studies into diet, disease and longevity found that Japan and Europe’s three countries with the longest life expectancy all have diets with substantial quantities of meat and/or dairy products. A large scale British study matching vegetarians with “moderate” omnivores and a European investigation found no measurable difference in mortality from circulatory diseases and all causes between meat eaters and vegetarians.

However, according to work done by Anthony Worsley and Grace Skrzpiec in the past 20 years, one of the largest groups of vegetarians are teenagers, specifically upper middle class teenage girls. Their research found that “teenage vegetarianism is primarily a female phenomenon, ranging in prevalence, according to definition, from 8 to 37% of women and 1 to 12% of men. Support for vegetarian practices was high especially from mothers (63%) and classmates (46%).”

The findings of the research were that teenage vegetarianism is largely a female phenomenon characterized by meat avoidance, concern for the environment, animal welfare, gender equity, weight-loss behaviors and high concern with body appearance. The scientists found a strong association between adolescent vegetarianism and extreme weight-loss behaviors, which may be according to the authors indicative of eating disorders.

Homo sapiens are an omnivore with a high degree of natural preference for meat consumption. According to Dr. Vaclav Smil only later did increasing density of populations create the need to abandon hunting and gathering and progressively increase permanent settlements with crop farming. The agrarian life was accompanied by cultural adaptions of meat restrictions and taboos turned meat into a relative rare foodstuff for the vast majority of the population in traditional agricultural societies. The return to more frequent meat eating has been a transition in affluent economies.

Meat is one of the best sources of dietary iron because it supplies the mineral as heme iron that is easily absorbed in the small intestine and also helps to absorb the non-heme iron present in plants like spinach. Even modest meat consumption helps to prevent iron deficiency anemia. While men and children only require 8-11 mg/day of iron, pre-menopausal women require 18 mg/day and pregnant women require 27 mg/day of iron. (The groups most likely to be vegetarian needs the most iron- ironic?) Meat followed by dairy products is the single largest source of high quality protein, essential fatty acids and micro nutrients. Meat is also rich in B6, B12 and niacin as well as zinc. A zinc deficiency slows growth, increases infection rates, skin lesions and impairs wound healing. In addition an average weight adult needs 50 grams of protein a day and children must have adequate energy, protein and nutrient consumption to avoid stunting and deficiencies that could cause serious mental and cardiac problems in growing and developing Homo sapiens. The “typical” western diet reportedly contains between 85-95 grams of meat a day, so we could cut back on meat and work to optimize our diets for our tastes, and our bodies. People are different.

According to an interdisciplinary report prepared by the Food and Agriculture Organization of the United Nations, FAO, 26% of the earth’s surface is used as grazing land, 33% of all arable land is utilized to grow feed for animals, as much as 18% of greenhouse gas emissions come from raising primarily beef livestock, and it takes 1,800 gallons of water to produce a pound of beef. According to a recent article in New Scientist magazine “as much as 32% of greenhouse gas emissions come from rearing livestock.” I could not track down the source of that assertion. However, becoming a vegetarian is not necessarily the greenest choice.

According to Dr. Vaclav Smil there is lots of land used as pastureland around the world that cannot be used to grow crops. If this land is grazed properly it can be grazed sustainably forever. The grasses in the pasture cannot be digested by man, but cows and sheep can. This is the philosophy of a nearby farm, Polyface, operated by three generations of the Salatin family. The Salatin family built their farm by first rehabilitating the land. They planted trees, built compost piles, dug ponds, and moved cows daily with portable electric fencing, to create what they call a “perennial prairie polyculture.” Grazing animals in rotation contributes to the biological diversity. The pastured livestock and poultry at Polyface farm are moved frequently to new areas of the farm to allow the landscape healing and nutrient rebuilding. Dr. Vaclav Smil says that if we used only used sustainable grazing and fed livestock on crop residues we could still raise about two-thirds of the meat we do now, and we could extend the meat using plant protein. Still, his suggestions are processed and created food. There may simply be a limit on how much food our earth can produce sustainably.

Thursday, February 5, 2015

Neanderthal Driven Extinct by Homo sapiens or Climate Change?

Kate Wong is an Editor at Scientific American and over the past half a decade has published a series of in depth articles on her favorite topic, the Neandertal. You should check out the latest in this series in the February Scientific American. This species, Neandertal, our closest relatives, ruled Europe and western Asia for 200,000-210,000 years. About 44,000 years ago modern humans, Homo sapiens, who evolved in Africa spread to Europe and western Asia and beyond. Improved dating methods applied by scientists from Oxford University to dozens of Neanderthal and Homo sapiens sites indicate that over a period of about 2,600-5,400 years both species coexisted in Europe until the Neandertal disappeared from the archeological record around 39,000 years ago.

Scientists have long debated what led to the disappearance of the Neandertal. Before improvements in dating methods showed that rather than disappearing immediately after Homo sapiens invaded Europe, it was believed that Homo sapiens simply replaced the Neanderthal. They were either conquered or out competed. For over a century Neandertals were considered an inferior species to Homo sapiens. However, in this century there has been a major reassessment of the Neandertals. New discoveries about Neandertals in archaeology have forced re-evaluations of their anatomy, the size of their brains, their cognitive ability, and revelations about their genetic makeup.

In 1997 when the first DNA studies using DNA obtained from three Neandertal bones from the Vindija cave in Croatia were done they sequenced Neandertal mitochondrial DNA and did not find any commonality with modern man. Mitochondria have their own DNA, which is distinct from the much longer DNA sequence that resides in the cell’s nucleus. The findings in 1997 were that Neanderthals had not made any contributions to modern Homo sapiens mitochondrial DNA.

However in 2010, the same team successfully sequenced the nuclear DNA and looked at patterns of nuclear genome variation in present-day humans. They identified 12 genome regions where non-Africans exhibited variants that were not seen in Africans and that were possibly derived from the Neandertals, who lived not in Africa but Eurasia (Europe and western Asia). The scientists have since concluded that between 1.5%- 2.1% of the DNA of people today who live outside Africa came from Neandertals, the result of interbreeding.

These results of the DNA sequencing and better dating disprove the strict Out of Africa replacement model of modern human origins. This was the theory that was in vogue when I studied Anthropology. Dr. Christopher B. Stringer of the Natural History Museum in London has revised that theory saying “the Neandertal genome strongly suggests those genes were not lost, and that many of us outside of Africa have some Neandertal inheritance.”

The latest research has found that the Neandertal fashioned and used bone tools for working hides 53,000-41,000 years ago. From a Neanderthal site 90,000 years old is evidence of string making possibly for nets, traps and bags. Traces of worked wood indicating tool making have been found. Work by the Max Planck Institute for Evolutionary Anthropology in Germany has found evidence throughout Europe and western Asia that Neandertals were omnivores that consumed cooked wheat, tubers and barley and were making and using stone tools. Recent discoveries have found that Neandertals were tool makers, omnivores and engaged in symbolic thought (cave art) before the arrival of Homo sapiens. These findings have made the decline and extinction of the Neanderthal more puzzling.

The latest extinction theories focus on climate change and subtle differences in behavior and biology. That is not surprising since all current scientific theories focus on climate change. The theory is that Homo sapiens evolved a unique combination of physical and behavioral characteristics that Neandertal did not possess at least to the same degree. The complex brains of Homo sapiens enabled them to interact with each other and with their surroundings in new and different ways. As the environment became more unpredictable, bigger brains helped Homo sapiens survive. The Neanderthal ruled Europe and Western Asia (Eurasia) for over two hundred thousand years through periods of changing climate, but died out because they did not adapt to climate change.

The Neandertal were a more spread out and less connected population than the more densely populated Africa home of the Homo sapiens. The vast spans of ice isolated the groups from one another. Once the glaciers melted and the European and western Asia continents were more hospitable, Homo sapiens swarmed into Europe and western Asia and lead to the Neandertal demise by dramatic population increases, taking over the Neandertal hunting and gathering grounds and swamping their gene pool.

Population pressure has driven Homo sapiens. In just the past 12,000 years Homo sapiens have transitioned from hunting and gathering to producing food and changing our surroundings. Food and population pressure led to farming and herding animals. As Homo sapiens invested more time in producing food, they ceased to be nomad tribes. Villages became towns, and towns became cities. We learned to build, to move water, build pumps and engines and burn fossil fuels to put ever more Homo sapiens on earth.

With more food available, the human population continued to increase dramatically. Homo sapiens spread to every continent and geometrically expanded their numbers; there are over 7 billion of our species on earth today. Homo sapiens have altered the world in ways that benefit them greatly. The transformation has unintended consequences for other for other species as well as for our own. Our great strength may also prove to be a challenge to our survival.

In 2013 when the Intergovernmental Panel on Climate Change (IPCC) released the Fifth Assessment Report on climate change they reported that the IPCC expects global surface temperatures for the end of the 21st century to increase 2.7°F to 3.6°F relative to 1850 to 1900 time period. “Heat waves are very likely to occur more frequently and last longer. As the Earth warms, we expect to see currently wet regions receiving more rainfall, and dry regions receiving less, although there will be exceptions,” said Co-Chair Thomas Stocker in the press release. Dr. Stocker concluded his comments by reminding us that as a result of our past, present and expected future emissions of CO2, climate change is inevitable, and will persist for many centuries even if emissions of CO2 were to stop today. So we get to see if and how Homo sapiens survive climate change.