Climate change and extreme weather

23 04 2012

I just saw this powerful video based on a recent editorial by Bill McKibben  in the Washington Post on May 23, 2011.   Narritation is  by Stephen Thomson of Plomomedia.com, who accompanies the piece with striking footage of the events Bill wrote about.

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Thanksgiving blessings

25 11 2009

I have been trying to think of a good subject for this week – one that isn’t too dire and downbeat – while we in the United States are in the midst of our national feast called Thanksgiving.   We’re living in a country where I can get a free range turkey with all the bells and whistles – or soybeans from Texas, the best orange marmelade from Scotland or fresh raspberries from Chile.  This abundance comes at a cost –  it is estimated that if United States’ consumption rates were mimicked by the entire human population,  it would take the resources of 5.3 Earths.(1)  It is this abundance that allows us to ignore what is happening in the rest of the world.  Doesn’t have a direct bearing on textiles, but the long term implications are there.

An inescapable fact in most of the developing world – and largely unnoticed in the United States except in slightly higher food prices –  is that in the past couple of years, food prices have soared.  Between the mid-1970’s and 2005,  grain supplies rose and prices fell by about a half, leading “many experts to believe that there was no limit to humanity’s capacity to feed itself.” (2)  But then in 2006, the situation reversed:  food prices rose slightly that year, then increased by about a quarter in 2007, and finally skyrocketed in 2008.  Between 2006 and 2008, average world prices for rice rose by 217%, wheat by 136% and corn by 125% (3)  These rising prices meant that many people could not afford food – and  this led to riots  in 15 countries around the world in 2008.  Countries that could produce enough food for export worried about feeding their own populations, and placed restrictions on exports.  This became a serious problem for countries which were not fully self sufficient in food production.

Susan Payne, chief executive of Emergent Asset Management, said that by 2020 they think there could be genuine food shortages in the world.   During a talk on Africa’s agricultural potential, she showed a series of slides citing chilling statistics:

  • grain stocks worldwide are at their lowest levels in 60 years
  • global warming is turning arable land into desert
  • freshwater is dwindling and China is draining its reserves
  • and the really big problem:  the world’s population is growing by 80,000,000 hungry people each year.

The United Nations Food and Agriculture Organization estimates that in order to feed the world’s projected population in 2050, we need to increase the amount of cereals in the world’s food supply to an amount equal to the total production of Australia in 2008.

Indeed, the food crisis of 2008 has put the spotlight on a new area of business potential, where the payoff could be immense: the area of agricultural investment and the newly lucrative world of food trade.  Financial firms like Goldman Sachs and BlackRock have already invested hundreds of millions of dollars in overseas agricultural projects.   Africa is the focus of their interest because in Africa land and labor come so cheaply that the risks are assumed to be worthwhile.  As a example, an Ethiopian farmer’s  yields for their wheat crops  are only about a third as much per acre as their counterparts in other parts of the world.  But with the addition of advanced implements, and improved seeds and fertilizer, these yields can be doubled.  Ethiopia, like all of Africa, is full of such opportunities.

Andrew Rice wrote an article in the November 22 New York Times Magazine in which he describes what some of the wealthy nations are doing to ensure a food supply for their people.

The nations of the Persian Gulf already import 60% of their food, and Saudi Arabia plans to phase out wheat production by 2016 in order to maintain its supply of underground freshwater.  Instead of relying on technology to increase their capacity for growing food  (along the lines of the Green Revolution of the 1960s),  these countries feel that they must control the means of production.  They want land.

The Saudi Arabian government and individual Saudi bankers and executives have said they intend to spend billions of dollars to establish plantations to produce rice and other staple crops in Africa, in nations like Mali, Senegal,  Sudan and Ethopia.  A newly formed company, Saudi Star Agricultural Development, announced it’s plans to “obtain the rights” to more than a million acres – that’s about the size of Delaware – in Ethiopia.  And in the Rift Valley of Ethiopia, farms are already growing fruits and vegetables for export to the Persian Gulf.(4)

This raises the question:  what about the people who live in Mali, Senegal, Sudan and Ethopia?  Do they benefit from these investments?  Am I the only one who thinks this spells trouble?

(1) New Economics Foundation, http://www.naturalnews.com/022890.html

(2) Rice, Andrew, “Agro-Imperialism”, New York Times Magazine, November 22, 2009

(3)  “Cyclone fuels rice price increase”, BBC News, May 7, 2008

(4) Rice, op.cit.





Air pollution and your cashmere sweater

4 11 2009

We’ll be at Greenbuild next week, booth 910, with our good friends from LIVE Textiles.  Please stop by to see us if you’re there.

We are introducing a new organic wool upholstery fabric at Greenbuild  (we’re hoping it will be GOTS certified, though it is touch and go as to whether the certificate will be in place by then – there are so many hoops!).    So for the past six months or so we’ve been learning lots about wool – and wool is a complicated subject!  It’s a gorgeous fiber, but it has, as we say, issues.  Not unsolvable, but like everything you have to know your suppliers and what questions are important to ask.  We talked about wool and animal husbandry in two previous posts (“What does organic wool mean?” 8.11.09 and “Why does wool get such high embodied energy ratings?” 8.4.09);  some of the issues surrounding wool are enumerated in those posts.

I’m always a sucker for soft and luxurious, so naturally when talking about wool I began hinting I’d like a cashmere fabric – or wool/cashmere blend.  But we looked into cashmere, and what we found is startling and unexpected: a story of how your cashmere sweater pollutes the air you breathe.    There is an improbable connection, according to Evan Osnos of the Chicago Tribune, “between cheap sweaters, Asia’s prairies and America’s air, (which) captures how the most ordinary shifts in the global economy are triggering extraordinary change.”  Please read Mr. Osnos’ article, “China’s Great Grab”, from which most of the information in this blog is taken.   He won the Asia Society’s Osborn Elliott Prize for distinguished journalism for this series.

Cashmere has recently become ubiquitous –  cashmere sweaters, for example, once so very high priced that the very word “cashmere” became synonymous with luxury,  are suddenly “affordable”.  Coincidentally, Saks Fifth Avenue ran a full page ad in Sunday’s  New York Times touting their low priced cashmere goods – and telling you to “Shop Smart”.   We’ll help you to shop smart – please read this post!

What happened to bring down the price of cashmere?  Behind this new affordable price tag is something the consumer rarely sees or thinks about: the cascade of consequences around the world when the might of Chinese production and western consumption converge on a scarce natural resource.

Cashmere comes from the downy underhair of special goats, the majority of which live in the coldest regions of China and Mongolia.  In fact, the world’s best and most expensive cashmere comes from the Alashan Plateau, an area in China’s north straddling the Mongolian border,  boiling hot in summer and way below zero in winter.  This area is part of China’s mythic grasslands, where Genghis Khan and his horde rode the limitless horizon.  The fiber itself, known as “diamond fiber” in China,  sells for 6 times the cost of ordinary wool.

This rare and wonderful fiber is remarkably soft, silky and warm.  Side by side under a microscope a single cashmere strand makes a human hair look like a rope.  And it was also synonymous with high price.  European spinning mills have sourced the best cashmere yarns from this region for years.

The combination of demand and high prices led to China’s rapid increase in production to meet that demand,  and  conditions were in place to create an almost perfect storm – with money to be earned from “diamond fiber”, herders rapidly increased their goat populations and caused severe overgrazing.  In  Inner Mongolia, for example, the livestock population increased from 2 million in 1949 to 28.5 million in 2004.(1)

20080318-desertification Julie Chaol

The goats are eating the grasslands bare:  Goats consume over 10% of their body weight daily in roughage, eating not just the grass but also their roots and stripping bark from seedlings, preventing the regrowth of trees.  The land is so barren that herders buy cut grass and corn by the truckload to keep their animals alive.  Overgrazing is so severe that the health of the goats is at risk: their birthrate is sinking and even the cashmere has begun to suffer from these stressed goats, with shorter, coarser, less valuable fiber.

In addition to stripping the land of all vegetation, the feet of these goats have been compared to stiletto heels, vs. the big soft pads of camel’s feet, which have a far lesser impact on the ground.  These “stiletto heel” hooves  pierce the crust formed on the land, and the fine sand beneath it takes flight.  So the animals remove the vegetation, and the winds finish the job by blowing away the top soil, transforming the grasslands into desert.

In this perfect storm, the rapid increase in the number of goats has occurred at the same time the area is undergoing a severe drought due to climate change.  The goats require water, which also leads to overuse of that resource.  So many cashmere plants and other industries have opened in Alashan that authorities must ration water, forcing each factory to close for days at a time. (2)

And without grass and shrubs to hold the dunes in place, the deserts in Alashan are expanding by nearly 400 square miles each year. The World Bank warned of grave consequences for the environment and for farmers.

Already desertification is causing millions of rural Chinese to migrate from their villages –  a migration on the scale of the Dust Bowl in the United States is taking place in China today. A study by the Asian Development Bank found 4,000 villages at risk of being swallowed by drifting sand (3)

Exhib_001031

But the environmental degredation doesn’t stop in Alashan.  Eroding grasslands means that silt is deposited into the headwaters of rivers that flow all across Asia: to India, Pakistan, Bangladesh and Southeast Asia.  And the dust storms, which have been a fact of life in this area of the world since before Genghis Kahn, are becoming increasingly common:  in the 1950s, China suffered an average of five dust and sand storms per year; in the 1990s storms struck 23 times each year.  (4)  These storms do a lot of damage:  A storm in 2002 forced 1.8 million South Koreans to seek medical help and cost the country $7.8 billion in damage to industries such as airlines and semiconductors, said the state-run Korea Environment Institute. (5)

And added to the damage the storms cause in China, they also act as a high altitude conveyor belt for pollution.  Think of it like this:  the dust and sand generated in Alashan  is sent east by the winds, where China’s coal powered industry adds pollution.  Together the noxious brew reaches the U.S. within five days, where it can combine with local pollution to exceed the limits of healthy air, according to Rudolf Husar, an atmospheric chemist at Washington University in St. Louis.(6)

According to Eric Osnos’ article, “Of most concern are ultra tiny particles that lodge deep in the lungs, contributing to respiratory damage, heart disease and cancer. One storm that began in China and Mongolia in spring 1998 caused a spike in air pollution that prompted health officials in Washington, Idaho, Oregon and British Columbia to issue warnings to the public.”

The situation has become so bad that herders are moving off the land to try their hand at trades in the cities, and the government is putting many new programs into place to help stem the damage which has been done (including banning grazing on some lands).  The price of cashmere has begun to climb.  But with ads such as the one from Saks, promoting yet another cheap product, these problems will continue to persist.

(1)  Osnos, Evan;  “China’s Great Grab: Your cheap sweather’s real cost”, The Chicago Tribune, December 16, 2006.

(2) Ibid.

(3) http://factsanddetails.com/china.php?itemid=389&catid=10&subcatid=66#07)

(4) Osnos, op cit.

(5) Ibid.

(6) Ibid.





Textiles, organic agriculture and water use

20 10 2009

A new study focused on global water issues, commissioned by an  international network of  scientists,   found that people around the world view water issues as the planet’s top environmental problem –  greater than air pollution, depletion of natural resources, loss of habitat or climate change. (click here to read more on this study).  That shouldn’t be too surprising, given the alarming statistics we’ve been hearing recently:

From World Water Day:  “The world water crisis is one of the largest public health issues of our time. Nearly 1.1 billion people (roughly 20% of the world’s population) lack access to safe drinking water. Water is essential to the treatment of diseases, something especially critical for children.  This problem isn’t confined to a particular region of the world. A third of the Earth’s population lives in “water stressed” countries and that number is expected to rise dramatically over the next two decades.”

From Water.org:

  • 3.575 million people die each year from water-related disease.
  • The water and sanitation crisis claims more lives through disease than any war claims through guns.
  • An American taking a five-minute shower uses more water than the typical person living in a developing country slum uses in a whole day

Given that the textile industry uses vast quantities of water – and is the #1 industrial polluter of fresh water on Earth – it is necessary that the industry at the very least institute water treatment at each and every mill so that the water returned to the ecosystem is safe and doesn’t cause harm.  Currently the industry is adopting voluntary certifications which demonstrate to consumers what they are doing to protect the environment.    Some certifications include standards for water treatment (such as GOTS, C2C, SMaRT) and some do not (such as Oeko-Tex, GreenGuard).  But these certifications are voluntary, and water treatment is expensive.  The market doesn’t yet know enough to demand safe fabrics, let alone better processing procedures.  The industry is not adopting these standards quickly nor is there much discussion about water treatment by American textile mills.  It is not enough.  We are calling for a government mandate for water treatment (pH, temperature and COD and BOD content) at each mill in the United States with standards that really have teeth.

We recognize that industrial water pollution is only part of the problem – that the consumer piece of the equation (laundering) is important also.  But the government cannot mandate how you launder your clothes  –  while it does have the power to change and monitor effluent levels from industry.

We  have a made a Faustian bargain:  we have exploited our natural resources and given up long term conservation for short term gain.  I know it’s easy to point fingers after the fact, and it would have been unusual for anybody (including myself) to point out the folly of using up our limited resources when the gains from doing so were so great.  But time is change, and we’re now facing different circumstances.  It is not really even a question of whether we should do this or not,  because our ability to act has been taken away – the water is simply disappearing.  It’s not being replaced.  We have to adapt to circumstances – and now the only question is “how”?  Let me tell you a story.

There are generally two images of the Great Plains that most Americans of my generation keep in their minds.  The first is that iconic black and white photograph by Arthur Rothstein of the 30’s Dust Bowl:

dust-bowl_photo

The second is of a swath of verdant farmland, ripe with wheat, corn, sorghum, soybeans and cotton –   field after verdant field stretching to the horizon:

golden wheat

This startling change can be attributed to the Ogalala Aquifer, one of the largest aquifer systems in the world.  Total water storage in the aquifer is about equal to that of Lake Huron, and it is the single most important source of water in the High Plains region, providing nearly all the water for residential, industrial and agricultural use.   It is this water that transformed the Great Plains from a region of subsistence farming into one of the richest agricultural areas of the world – $20 billion per year in food and fiber depends on this aquifer.   It stretches across all or portions of eight states and underlies 174,000 square miles.  It lies relatively near the land surface in most of this area, and could almost always be counted on to yield water to a well drilled into it.

In the 1930s, people began to realize the potential of the vast water supply that lay beneath them.  Irrigation of cropland began in earnest.   And very little water conservation technology was available:  lots of water was lost to evaporation and deep percolation; open, unlined ditches were used to transport the water to the fields; it wasn’t uncommon to have evaporation losses of 50%. Early settlers thought the water was inexhaustible.

Ogalala a

It was not.  And today we risk having the first image above superimposed again on the second.   That is because  the Ogalala Aquifer is being sucked dry.

Today, the Ogalala Aquifer  is being depleted at a rate of 12 billion cubic metres a year – amounting to a total depletion to date of a volume equal to the annual flow of 18 Colorado Rivers.(1)  Although precipitation and river systems are recharging a few parts of the aquifer, in most places “nature cannot keep up with human demands.” (2)

According to a major study just completed by Camp Dresser & McKee, a Boston engineering firm, 5.1 million acres of irrigated land (an area the size of Massachusetts) in six Great Plains states will dry up by the year 2020 ( that’s 10 years!), and millions of acres of irrigated acres will be lost across a 5-state area.  Yet this drastic estimate, declares Herbert Grubb of the Texas department of water resources, is  “20% too optimistic.”(3)

Ship Bright is a blog concerned with fresh water issues, and the post on October 12, 2009 (read it here) features a great description of the current situation, including what they call the “planned bankruptcy”  caused by current water management strategies.

Farmers in the area are waking up to the fact that they will have to use less water – and this in the face of global warming predictions that the area served largely by the Ogalala Aquifer is predicted to be hotter and drier.(4)

One way to conserve water is to use more efficient irrigation systems, another way is to grow crops that require less water.    Then there is “going dryland” – meaning using no irrigation at all.  That requires using some techniques such as leaving stubble in the ground and planting a new crop in the residue.  This not only reduces soil erosion but also decreases evaporation and catches more blowing snow than bare ground.  It also reduces moisture loss by the equivalent of an inch or more of rainfall annually, and in an area that averages only 18 inches of rainfall per year that’s a lot.

These techniques have long been part of organic agriculture  – growing what is appropriate for an area, using what is available.  Many organic crops which do not use artificial fertilizers also have lower water requirements.  There is some research going on into the suitability of cotton as a replacement for corn in this area, because cotton crops use less water than corn.

In addition, some farmers are looking into converting their land back to grasslands, which would provide wildlife habitat, and grazing land for cattle or even buffalo.  (See our blog “Organic Agriculture and Climate Change” 7.29.09 and “Why does wool get such high embodied energy ratings”, 8.4.09).   And once a national carbon market is established, farmers could sell credits for storing carbon in grassland soil.  But the government doesn’t provide lucrative financial incentives for grassland conversion as it does for the production of corn or other commodities.

Once again, organic agriculture proves to be important, perhaps crucial, in our fight modify our water use and perhaps allow the Ogalala Aquifer to recharge.

(1)  Little, J.B., “Saving the Ogalala Aquifer”, Scientific American “Earth 3.0”, Vol 19, No. 1, 2009

(2) Ibid.

(3) Stengel, Woodbury, Allis, “Environment: Ebbing of the Ogalala”, Time, May 10, 1982

(4)Bock, J., Bowman, W., Bock, C, “Global Change in the High Plains of North America”, Institute of Arctic and Alpine Research, University of Colorado, Great Plains Research, Vol.1, No. 2





Why does wool get such high embodied energy ratings?

4 08 2009

The more I learn about organic farming the more impressed I become with the dynamics of it all.   As Fritz Capra has said, we live in an interconnected and self-organizing universe of changing patterns and flowing energy. Everything has an intrinsic pattern which in turn is part of a greater pattern – and all of it is in flux.  That sure makes it hard to do an LCA, and it makes for very wobbly footing if somebody takes a stand and defends it against all comers.

For example, I have been under the impression (based on some published LCA’s) that the production of wool is very resource inefficient, largely based on the enormous need for water: it’s generally assumed that 170,000 litres of water is needed to produce 1 KG of wool    (versus anywhere from 2000 to 5300 to produce the same amount of cotton).  That’s because the livestock graze on land and depend on rainwater for their water – and some LCA’s base the water use on the lifetime of the sheep (reminding me to check the research parameters when referring to published LCA’s).

In addition, industrial agricultural livestock production often results in overgrazing.  As we now see in the western United States, overgrazing in extreme cases causes the land to transform from its natural state of fertility to that of a desert. At the very least, it severely limits plant reproduction, which in turn limits the soil’s ability to absorb water and maintain its original nutrient balance, making overgrazing difficult to recover from. And then there’s methane: livestock are often vilified for producing more greenhouse gases than automobiles.

The exciting thing is that what is known as “holistic management” of the soil makes it possible to use animals to improve, rather than degrade, land.  What’s consistently ignored in the research  is the failure to distinguish between animals raised in confined feedlots and animals grazing on rangeland  in a holistic system.  Research on holistic land management is, in fact, showing that large grazing animals are a vital and necessary part of the solution to climate change and carbon sequestration. Read about holistic land management on the Holistic Managmeent Institute (HMI) website.

The reason holistic practices work, according to HMI, is that grazing animals and grassland co-evolved.  According to the HMI website, hooves and manure accomplish what mechanical tilling and petrochemical fertilizers cannot: healthy, diverse grassland with abundant root systems and improved soil structures that makes highly effective use of existing rainfall.  Domestic animals can be managed in ways that mimic nature, called “planned grazing”:  rather than allowing animals to linger and eat from the same land repeatedly,  animals are concentrated and moved according to a plan which allows the land long periods of rest and recovery.   This planned grazing allows the animals to till packed soil with their hooves, distribute fertilizer and seed in their manure and urine, and move from one area to another before they can overgraze any one spot. In fact, the animals help maintain the soil, rather than destroying it, and increase the amount of organic matter in the soil, making it function as a highly effective carbon bank. Properly managed, grazing animals can help us control global climate change:  soil carbon increased 1% within a 12 month period  in a planned grazing project (a significant increase).

This carbon is essential to not only feeding soil life and pasture productivity, but it also affects water infiltration rates. On one trial site where planned grazing was implemented, within two years, the  soil water infiltration rate increased eightfold in comparison to the conventional grazing treatment.

In addition, holistic management of grazing animals eliminates the need for the standard practice of burning crop and forage residues.  That burning currently sends carbon directly into the atmosphere.  If we convert just 4 million acres of land that’s operating under the traditional, conventional agriculture model to holistically managed land – so the residue is not burned – the carbon is captured rather than released.   Look at the difference in erosion in the picture below: compare the severely eroded, conventionally managed riverbank on the left with the Holistically Managed bank on the right.  All the shrubbery and grass means abundant root systems and healthy soil infrastructure underground – both of these sequester CO2.

HOLISTIC mgmtWhat you see on the right is the result of managed animal impact.                     Source: Holistic Management International

According to Christine Jones, Founder, Australian Soil Carbon Accreditation, “The fabulous thing about sequestering carbon in grasslands is that you can keep on doing it forever – you can keep building soil on soil on soil… perennial grasses can outlive their owners; they’re longer-lived than a lot of trees, so the carbon sequestration is more permanent than it is in trees: the carbon’s not going to re-cycle back into the atmosphere if we maintain that soil management… and there’s no limit to how much soil you can build… for example, we would only have to improve the stored carbon percentage by one percent on the 415 million hectares (1,025,487,333 acres) of agricultural soil in Australia and we could sequester all of the planet’s legacy load of carbon. It’s quite a stunning figure.”

 

Data from a demonstration project in Washington State is confirming other worldwide research that grazing could be better for the land than growing certain crops in dryland farming regions – it reverses soil decline (erosion and desertification), restores soil health, and instead of losing carbon through tilling or systems requiring inputs (like wheat farming) planned grazing sequesters carbon; biomass to soak up carbon is increased, and the use of fossil fuel has been reduced by more than 90%.  Wildlife habitat has improved.  The Washington State project even sells carbon credits.

In April of this year, Catholic Relief Service, one of the country’s largest international humanitarian agencies, is launching a worldwide agricultural strategy that adopts a holistic, market oriented approach to help lift millions of people out of poverty.   Read more about this here.





Organic agriculture and climate change

29 07 2009

global6

The debate over sustainable agriculture has gone beyond the health and environmental benefits that it could bring in place of conventional industrial agriculture. For one thing, conventional industrial agriculture is heavily dependent on oil, which is running out; and it is getting increasingly unproductive as the soil is eroded and depleted. Climate change will force us to adopt sustainable, low input agriculture to ameliorate the worst consequences of conventional agriculture, and to genuinely feed the world.

And climate change is upon us.  I’m sitting in Seattle experiencing an “historic heat wave” while reading that the Hadley Center of the British Meteorological Organization has said the world’s temperature will increase by 8.8 degrees F rather than 5.8 degrees F this century.

The Inter-Governmental Panel on Climate Change (IPCC) has said we can expect a considerable increase in heat waves, storms, floods, and the spread of tropical diseases into temperate areas, impacting  the health of humans, livestock and crops. It also predicts a rise in sea levels up to 35 inches this century, which will affect something like 30% of the world’s agricultural lands (by seawater intrusion into the soils underlying croplands and by temporary as well as permanent flooding). If the Hadley Center is right, the implications will be even more horrifying: Melting of the Antarctic, the Arctic, and especially the Greenland ice-shields is occurring far more rapidly than was predicted by the IPCC. This will reduce the salinity of the oceans, which in turn  weakens (if not diverts) oceanic currents such as the Gulf Stream from their present course . And if that continues, it would eventually freeze up areas that at present have a temperate climate, such as Northern Europe.

According to the Institute of Science in Society, “It is becoming clear that climate change and its different manifestations (as mentioned above) will be the most important constraints on our ability to feed ourselves in the coming decades. We cannot afford to just sit and wait for things to get worse. Instead, we must do everything we can to transform our food production system to help combat global warming and, at the same time, to feed ourselves, in what will almost certainly be far less favorable conditions.”

But before we tackle the question of how best to feed ourselves during these “less favorable” times: how can organic agriculture help with global warming?

It’s generally assumed that various Greenhouse Gases (GHG) are responsible for
global warming and climate change.   On a global scale, according to a study commissioned by IFOAM, agriculture has been responsible for approximately 15% of all GHG emissions:

  • 25% of all CO2 emissions come from agriculture
  • 60% of CH4 (methane) emissions come from agriculture
  • 80% of N2O (nitrous oxide) emissions  come from agriculture

About 60% of the CO2 emissions from human and animal activities is absorbed by the oceans and plants; the remaining 40% builds up in our atmosphere.    So what to do about the 40% that’s building up in our atmosphere?  Where can it be stored?

428

In  looking at ways to “defuse” this CO2 build up, scientists began looking at carbon “sinks”.  Carbon sinks are natural systems that suck up and store carbon dioxide from the atmosphere. The main natural carbon sinks are plants, the ocean and soil. Plants grab carbon dioxide from the atmosphere to use in photosynthesis; some of this carbon is transferred to soil as plants die and decompose. The oceans are a major carbon storage system for carbon dioxide. Marine animals also take up the gas for photosynthesis, while some carbon dioxide simply dissolves in the seawater.

Initially forests were thought to be the most efficient way to sequester (or absorb) this carbon.  It was thought that escalating fossil fuel consumption could be balanced by vast forests breathing in all that CO2.   But  these sinks, critical in the effort to soak up some of our greenhouse gas emissions, may be maxing out, thanks to deforestation, and human-induced weather changes that are causing the oceanic carbon dioxide “sponge” to weaken.

New data is beginning to show that it may be that the soil itself makes more of a difference (in terms of carbon sequestration)  than what’s growing on it.  On a global scale, soils hold more than twice as much carbon as does vegetation (1.74 trillion tons for soil vs. 672 billion tons for vegetation) – and more than twice as much as is contained in our atmosphere.

The Rodale Institute Farming Systems Trial (FST), launched in 1981, is a 12 acre side by side experiment comparing three agricultural management systems: one conventional, one legume-based organic and one manure-based organic.  In 23 years of continuous recordkeeping,  the FST’s two organic systems have shown an increase in soil carbon of 15 – 23%, with virtually no increase in non-organic systems.

carbonsoil

This soil carbon data  shows  that improved global terrestrial stewardship–specifically including regenerative organic agricultural practices–can be the most effective currently available strategy for mitigating CO2 emissions. [2]

But although it is well established that organic farming methods sequester atmospheric carbon, researchers have yet to flesh out the precise mechanisms by which this takes place.   One of the keys seems to be in the handling of organic matter – while conventional agriculture typically depletes organic matter, organic farming builds it thru the use of composed animal manures and cover crops.  In the FST, soil carbon levels increased more in the manure-based organic system than in the legume-based organic system, presumably because of the incorporation of manures, but the study also showed that soil carbon depends on more than just total carbon additions to the system–cropping system diversity or carbon-to-nitrogen ratios of inputs may have an effect. “We believe that the differences in decay rates [of soil organic matter] have a lot to do with it,” says Hepperly, since “soluble nitrogen fertilizer accelerates decomposition” in the conventional system.

The people at Rodale put the carbon sequestration argument into an equivalency we can all understand: think of it in terms of the number of cars that would be taken off the road each year by farmers converting to organic production.  Organic farms sequester as much as 3,670 pounds of carbon per acre-foot each year. A typical passenger car, according to the EPA, emits 10,000 pounds of carbon dioxide a year (traveling an average of 12,500 miles per year). Here’s how many cars farms can take off the road by transitioning to organic:  car

U.S. agriculture as currently practiced emits a total of 1.5 trillion pounds of CO2 annually into the atmosphere. Converting all U.S. cropland to organic would not only wipe out agriculture’s massive emission problem, but by eliminating energy-costly chemical fertilizers, it would actually give us a net increase in soil carbon of 734 billion pounds.

Organic agriculture is an undervalued and underestimated climate change tool that could be one of the most powerful strategies in the fight against global warming, according to Paul Hepperly, Rodale Institute Research Manager.  In addition to emitting fewer GHGs while sequestering carbon, organic agriculture uses less energy for production.  A study done by Dr. David Pimentel of Cornell University found that organic farming systems used just 63% of the energy required by conventional farming systems, largely because of the massive amounts of energy requirements needed to synthesize nitrogen fertilizers.

Taking it one step further beyond the energy inputs we’re looking at, which help to mitigate climate change, organic farming:

  • eliminates the use of synthetic fertilizers, pesticides and genetically modified organisms (GMOs) which is  an improvement in human health and agrobiodiversity
  • conserves water (making the soil more friable so rainwater is absorbed better – lessening irrigation requirements and erosion)
  • ensures sustained biodiversity
  • and compared to forests, agricultural soils may be a more secure sink for atmospheric carbon, since they are not vulnerable to logging and wildfire.

Organic production has a strong social element and includes many Fair Trade and ethical production principles.  As such it can be seen as more than a set of agricultural practices, but also as a tool for social change.[3] For example, one of the original goals of the organic movement was to create specialty products for small farmers who could receive a premium for their products and thus be able to compete with large commercial farms.

And actually, it seems that modern industrial agriculture is on the way out.  The Food and Agriculture Organization of the United Nations (FAO) admitted in 1997 that wheat yields in both Mexico and the USA had shown no increase in 13 years  – blamed on the fact that fertilizers are becoming  less and less effective, as are pesticides.   The farmers are losing the battle.  Conventional agrochemical use (which includes many highly toxic substances) also has many immediate human impacts:  documented cases of short term illnesses, increased medical costs and the build up of pesticides in human and animal food chains.  The chemicals also contaminate the drinking and ground water.  And industrial agriculture is far too vulnerable to shortages in the availability of fuel and to increases in the price of oil.

That’s a lot to think about when looking for your next T shirt, so before you plunk down your money for another really cool shirt,  think about what you  will be getting in exchange.


[1] I should point out that although “sinks” in vegetation and soils  have a high
potential to mitigate increases of CO2 in the atmosphere, they are not
sufficient to compensate for heavy inputs from fossil fuel burning.  The long-term solution to global warming is simple:  reduce our use of fossil fuel, somehow, anyhow!
Yet the contribution from agriculture  could buy time during which
alternatives to fossil fuel can take affect – especially if that agricultural system is organic.

[2] http://www.rodaleinstitute.org/files/Rodale_Research_Paper-07_30_08.pdf

[3] Fletcher, Kate, Sustainable Fashion and Textiles, p. 19





Why is recycled polyester considered a sustainable textile?

14 07 2009

 

plastic_bottles

Synthetic fibers are the most popular fibers in the world – it’s estimated that synthetics account for about 65% of world production versus 35% for natural fibers.[1] Most synthetic fibers (approximately 70%) are made from polyester, and the polyester most often used in textiles is polyethylene terephthalate (PET).   Used in a fabric, it’s most often referred to as “polyester” or “poly”.

The majority of the world’s PET production – about 60% – is used to make fibers for textiles; about 30% is used to make bottles.   It’s estimated that it takes about 104 million barrels of oil for PET production each year – that’s 70 million barrels just to produce the virgin polyester used in fabrics.[2] That means most polyester – 70 million barrels worth –  is manufactured specifically to be made into fibers, NOT bottles, as many people think.  Of the 30% of PET which is used to make bottles, only a tiny fraction is recycled into fibers.  But the idea of using recycled bottles – “diverting waste from landfills” – and turning it into fibers has caught the public’s imagination.

The reason recycled polyester (often written rPET) is considered a green option in textiles today is twofold, and the argument goes like this:

  1. energy needed to make the rPET is less than what was needed to make the virgin polyester in the first place, so we save energy.
  2. And  we’re keeping bottles and other plastics out of the landfills.

Let’s look at these arguments.

1) The energy needed to make the rPET is less than what is needed to make the virgin polyester, so we save energy:

 

It is true that recycling polyester uses less energy that what’s needed to produce virgin polyester.  Various studies all agree that it takes  from 33%  to 53% less energy[3].  If we use the higher estimate, 53%,  and take 53% of the total amount of energy needed to make virgin polyester (125 MJ per KG of ton fiber)[4], the amount of energy needed to produce recycled polyester in relation to other fibers is:

Embodied Energy used in production of various fibers:

energy use in MJ per KG of fiber:

hemp, organic

2

flax

10

hemp, conventional

12

cotton, organic, India

12

cotton, organic, USA

14

cotton,conventional

55

wool

63

rPET

66

Viscose

100

Polypropylene

115

Polyester

125

acrylic

175

Nylon

250

rPET is also cited as producing far fewer emissions to the air than does the production of  virgin polyester: again estimates vary, but Libolon’s website introducing its new RePET yarn put the estimate at 54.6% fewer CO2 emissions.  Apply that percentage to the data from the Stockholm Environment Institute[5], cited above:

KG of CO2 emissions per ton of spun fiber:

crop cultivation

fiber production

TOTAL

polyester USA

0

9.52

9.52

cotton, conventional, USA

4.2

1.7

5.89

rPET

5.19

hemp, conventional

1.9

2.15

4.1

cotton, organic, India

2

1.8

3.75

cotton, organic, USA

0.9

1.45

2.35

Despite the savings of both energy and emissions from the recycling of PET, the fact is that it is still more energy intensive to recycle PET into a  fiber than to use organically produced natural fibers – sometimes quite a bit more energy.

2) We’re diverting bottles and other plastics from the landfills.

 

That’s undeniably true,  because if you use bottles then they are diverted!

But the game gets a bit more complicated here because rPET is divided into “post consumer” PET and “post industrial” rPET:  post consumer means it comes from bottles; post industrial might be the unused packaging in a manufacturing plant, or other byproducts of manufacturing.  The “greenest” option has been touted to be the post consumer PET, and that has driven up demand for used bottles. Indeed, the demand for used bottles, from which recycled polyester fibre is made, is now outstripping supply in some areas and certain cynical suppliers are now buying NEW, unused bottles directly from bottle producing companies to make polyester textile fiber that can be called recycled.[6]

Using true post consumer waste means the bottles have to be cleaned (labels must be removed because labels often contain PVC) and sorted.  That’s almost always done in a low labor rate country since only human labor can be used.   Add to that the fact that the rate of bottle recycling is rather low – in the United States less than 6% of all waste plastic gets recycled [7].  The low recycling rate doesn’t mean we shouldn’t continue to try, but in the United States where it’s relatively easy to recycle a bottle and the population is relatively well educated in the intricacies of the various resin codes, doesn’t it make you wonder how successful we might be with recycling efforts in other parts of the world?

pet-recycling-graph-2 SOURCE: Container Recycling Institute

There are two types of recycling:  mechanical and chemical:

    • Mechanical recycling is accomplished by melting the plastic and re-extruding it to make yarns.  However, this can only be done  few times before the molecular structure breaks down and makes the yarn suitable only for the landfill[8] where it may never biodegrade, may biodegrade very slowly, or may add harmful materials to the environment as it breaks down (such as antimony).  William McDonough calls this  “downcycling”.
    • Chemical recycling means breaking the polymer into its molecular parts and reforming the molecule into a yarn of equal strength and beauty as the original.  The technology to separate out the different chemical building blocks (called depolymerization) so they can be reassembled (repolymerization) is very costly and almost nonexistent.

Most recycling is done mechanically (or as noted above, by actual people). Chemical recycling does create a new plastic which is of the same quality as the original,  but the process is very expensive and is almost never done, although Teijin has a new program which recycles PET fibers into new PET fibers.

The real problem with making recycled PET a staple of the fiber industry is this:  recycling, as most people think of it, is a myth.  Most people believe that plastics can be infinitely recycled  – creating new products of a value to equal the old bottles or other plastics which they dutifully put into recycling containers to be collected. The cold hard fact is that there is no such thing as recycling plastic, because it is not a closed loop.  None of the soda and milk bottles which are collected from your curbside are used to make new soda or milk bottles, because each time the plastic is heated it degenerates, so the subsequent iteration of the polymer is degraded and can’t meet food quality standards for soda and milk bottles.  The plastic must be used to make lower quality products.  The cycle goes something like this:

  • virgin PET can be made into soda or milk bottles,
  • which are collected and recycled into resins
    • which are appropriate to make into toys, carpet, filler for pillows, CD cases, plastic lumber products,  fibers or a million other products. But not new soda or milk bottles.
  • These second generation plastics can then be recycled a second time into park benches, carpet, speed bumps or other products with very low value.
  • The cycle is completed when the plastic is no longer stable enough to be used for any product, so it is sent to the landfill
    • where it is incinerated (sometimes for energy generation, which a good LCA will offset)  –
    • or where it will hold space for many years or maybe become part of the Great Pacific Garbage Patch![9]

And there is another consideration in recycling PET:  antimony, which is present in 80 – 85% of all virgin PET[10], is converted to antimony trioxide at high temperatures – such as are necessary during recycling, releasing this carcinogen from the polymer and making it available for intake into living systems.

Using recycled PET for fibers also creates some problems specific to the textile industry:

  • The base color of the recycled polyester chips vary from white to creamy yellow, making color consistency difficult to achieve, particularly for the pale shades.  Some dyers find it hard to get a white, so they’re using chlorine-based bleaches to whiten the base.
  • Inconsistency of dye uptake makes it difficult to get good batch-to-batch color consistency and this can lead to high levels of re-dyeing, another very high energy process.  Re-dyeing contributes to high levels of water, energy and chemical use.
  • Unsubstantiated reports claim that some recycled yarns take almost 30% more dye to achieve the same depth of shade as equivalent virgin polyesters.[11]
  • Another consideration is the introduction of PVC into the polymer from bottle labels and wrappers.
  • Many rPET fibers are used in forgiving constructions such as polar fleece, where the construction of the fabric hides slight yarn variations.  For fabrics such as satins, there are concerns over streaks and stripes.

Once the fibers are woven into fabrics, most fabrics are rendered non-recyclable  because:

  • the fabrics almost always have a chemical backing, lamination or other finish,
  • or they are blends of different synthetics (polyester and nylon, for example).

Either of these renders the fabric unsuitable for the mechanical method of recycling, which cannot separate out the various chemicals in order to produce the recycled yarn; the chemical method could  –   if we had the money and factories to do it.

One of the biggest obstacles to achieving McDonough’s Cradle-to-Cradle vision lies outside the designers’ ordinary scope of interest – in the recycling system itself. Although bottles, tins and newspapers are now routinely recycled, furniture and carpets still usually end up in landfill or incinerators, even if they have been designed to be  recycled [12] because project managers don’t take the time to separate out the various components of a demolition job, nor is collection of these components an easy thing to access.

Currently, the vision that most marketers has led us to believe, that of a closed loop, or cycle, in which the yarns never lose their value and recycle indefinitely is simply that – just a vision.  Few manufacturers, such as Designtex (with their line of EL fabrics designed to be used without backings) and Victor Innovatex (who has pioneered EcoIntelligent™ polyester made without antimony),  have taken the time, effort and money needed to accelerate the adoption of sustainable practices in the industry so we can one day have synthetic fabrics that are not only recycled, but recyclable.


[1]“New Approach of Synthetic Fibers Industry”, Textile Exchange,  http://www.teonline.com/articles/2009/01/new-approach-of-synthetic-fibe.html

[2] Polyester, Absolute Astronomy.com: http://www.absoluteastronomy.com/topics/Polyester and Pacific Institute, Energy Implications of Bottled Water, Gleick and Cooley, Feb 2009, http://www.pacinst.org/reports/bottled_water/index.htm)

[3] Website for Libolon’s RePET yarns:  http://www.libolon.com/eco.php

[4] Data compiled from:  “LCA: New Zealand Merino Wool Total Energy Use”, Barber and Pellow,                                                                       http://www.tech.plym.ac.uk/sme/mats324/mats324A9%20NFETE.htm and  “Ecological Footprint and Water

Analysis of Cotton, Hemp and Polyester”, by Cherrett et al, Stockholm Environment Institute

[5] “Ecological Footprint and Water Analysis of Cotton, Hemp and Polyester”, by Cherrett et al, Stockholm Environment Institute

[6] The Textile Dyer, “Concern over Recycled Polyester”,May 13, 2008,

[7] Watson, Tom, “Where can we put all those plastics?”, The Seattle Times, June 2, 2007

[8] William McDonough and Michael Braungart, “Transforming the Textile Industry”, green@work, May/June 2002.

[9] See http://www.greatgarbagepatch.org/

[10] Chemical Engineering Progress, May 2003

[11] “Reduce, re-use,re-dye?”,  Phil Patterson, Ecotextile News, August/September 2008

[12] “Taking Landfill out of the Loop”, Sarah Scott, Azure, 2006