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Photo courtesy: USDAgov
The following article was written by Janet Larsen, Director of Research for the Earth Policy Institute.
When most people hear the term “dust bowl,” they think of the American heartland in the 1930s, when a homesteading wheat bonanza led to the plowing up of the Great Plains’ native grassland, culminating in the greatest environmental disaster in U.S. history.
Despite warnings from researchers and some farmers, history repeated itself in the Soviet Virgin Lands Project in the 1950s to early 1960s. Some 100 million acres (40 million hectares) of grassland were plowed under in Russia, Kazakhstan, and western Siberia during Premier Nikita Khrushchev’s push to produce ever more food from the land. When drought hit, the topsoil started to blow away. By 1965, nearly half the newly-planted area was degraded by wind erosion. Yields plummeted. Ultimately farmers staged a retreat, abandoning much of that land.
Unfortunately, dust bowls are not just relics of the past. Today two new dust bowls are forming: one in northern China and southern Mongolia and the other in Africa south of the Sahara. Whereas the dust bowls in the United States and the Soviet Union were the result of overplowing, the main culprit in Asia and Africa is overgrazing. Although arid or semiarid grasslands are typically better suited for grazing livestock than for farming, once they are overstocked their protective grass covering deteriorates and they face erosion all the same.
Forty percent of China’s land area is grassland. Following agricultural reforms that began in the late 1970s, in which collectively-owned livestock were transferred to household ownership, China’s cattle herds grew from 52 million in 1980 to nearly 105 million in 2000, according to the U.N. Food and Agriculture Organization (FAO). Meanwhile, China’s population of sheep and goats ballooned from close to 180 million to 280 million. Such a high concentration of grazing animals has put unsustainable pressure on the land. For comparison, the United States — a country with comparable grazing capacity — hosts a similar number of cattle but only 9 million sheep and goats.
The fastest growth in China’s livestock occurred with goats; starting in the mid-1980s, the herd size doubled in just 10 years. This is particularly troubling because a fast expansion of goat populations relative to cattle can indicate grassland deterioration. Goats are hardy, able to survive where few other grazers can. They can make efficient use of remaining greenery on nearly barren landscapes. Yet large numbers of goats often portend further environmental degradation because as the animals remove existing vegetation, they leave soils vulnerable to erosion from wind or rain.
Noting that an extraordinary 90 percent of China’s grasslands are degraded, the Chinese government has embarked on restoration programs, including re-vegetation, grazing bans, and livestock confinement. The government also has moved nomadic herders off the land or limited their movement under the guise of environmental protection. Evidence from the field, however, reveals that disrupting traditional grazing patterns can exacerbate land degradation and leave pastoralists more vulnerable to the vagaries of the weather.
FAO data indicate that since 2000, China’s cattle numbers have shrunk by 20 million, and the growth in sheep and goat herds appears to have stalled. Whether this can be attributed to policies aimed at reducing herd size or the relocation of herders is unclear.
Meanwhile, much damage has been done, and China’s dust bowl rages on. More than a quarter of China’s land area is covered by desert, and each year spreading sands claim additional territory. Expanding deserts in the arid northwest are merging. Since 1950, more than 24,000 Chinese villages have been abandoned or are seriously in danger of succumbing to traveling dunes, with some 35 million people directly affected.
The effects reach far beyond the desert margins. Spring is the dust storm season. The snow melts and the wind picks up, transporting dust and sand particles from northern China and Mongolia as far as Beijing and on to Korea and Japan, sometimes even crossing the Pacific to cloud parts of North America. The China Meteorological Administration reports that a single severe dust storm in 2006 dumped 330,000 tons of dust from the west onto Beijing: a stunning 44 pounds for each of the city’s residents. In 2007, a dust storm originating in China’s spreading Taklimakan Desert circled the globe in just under two weeks.
Desert scholar Wang Tao notes that in the first decade of the twenty-first century, China experienced 87 dust storms. Records of very strong dust storms (in which visibility is reduced below 200 meters) show an increase over recent decades, from 5 in the 1950s to 13 in the 1970s, 23 in the 1990s, and 21 between 2000 and 2009. (See data.)
The Korean Ministry of the Environment notes a similar rise in dust storms arriving from China and Mongolia, with talk of a lengthening and strengthening “yellow dust season” in South Korea. Dust events clouded 23 days in the 1970s, 39 days in the 1980s, 77 days in the 1990s, and 118 days from 2000 to 2011.
As bad as Asia’s dust storms are, the largest source of dust in the atmosphere on a global scale is Africa. Dust has long traveled out of Africa’s deserts and drylands, which make up two thirds of the continent’s land area; in fact, dust blowing out of Chad’s Bodélé Depression is thought to help fertilize the lush Amazon rainforest. Nearly 75 percent of Africa’s drylands are degraded. With land suffering the double whammy of drought and overuse, dust carried out of West Africa has increased over the last 40 years. Studies suggest that the larger influx of African dust may even be teaming up with rising ocean temperatures to damage Caribbean coral reefs.
In the Sahelian zone south of the Sahara the squeeze is on, with fast-growing populations trying to eke out a living by farming or grazing herds on ever less productive land. Desertification is particularly acute in Burkina Faso, Chad, and Niger, as well as in Nigeria, Africa’s most populous country, where an estimated 868,000 acres are lost to desert each year. Conflicts over land between herders (largely Muslim) and farmers (largely Christian) are legion, with both groups exacerbating erosion. Nigerian pastoralists, largely in the country’s north, have dramatically expanded their herds, putting additional pressure on soils already vulnerable because of erratic rainfall. In 1990, Nigeria had 14 million cattle, 12 million sheep, and 23 million goats. By 2010, cattle populations had climbed just slightly to 17 million, but the number of sheep tripled to 36 million, and goats jumped to 56 million.
Both Africa and China have launched ambitious initiatives to halt the spread of deserts with Great Green Walls of trees. Political leaders — including former Nigerian President Olusegun Obasanjo (an early champion of the African Wall) and Abdoulaye Wade, former President of Senegal — tend to favor such large symbolic projects. Indeed in the throes of the U.S. Dust Bowl, President Franklin D. Roosevelt was similarly taken with the idea of a giant shelterbelt. But as happened in the United States, desert containment plans in the Sahel and China have broadened in scope beyond basic tree belts to encompass more holistic land management and poverty alleviation activities. The limited success at holding back the sands in China thus far, where since the early 1980s an estimated 40 billion trees have been planted (although far fewer have survived), confirms that stopping desertification involves much more than planting trees.
Climate change is complicating the matter even further. Large parts of the planet are trending toward dryness, with a marked increase in aridity since the 1970s, when global temperatures started to climb. As the Earth heats up further, droughts are projected to become even more pronounced. A rapid reduction in greenhouse gas emissions to prevent runaway global warming, along with a slowdown in the growth of both human and livestock populations to reduce pressure on the land, are what it will take to increase our chances of leaving dust bowls to history.
Arctic sea ice running low? No problem, according to scientists – technology can refreeze it. Photo courtesy: Yahoo!News
2012 marked a new record low for the extent of Arctic sea ice, but apparently that's not a problem. We can just refreeze it!
Reducing carbon dioxide emissions is the key to a lasting solution to 'human-enhanced' climate change, however since governments and industries aren't doing a very good job of meeting reduction goals, strategies to reduce the worst effects of climate change may be needed. Dr. David Keith, a Canadian physicist, climate scientist and public policy expert who teaches at Harvard University, has done extensive research into the field of Solar Radiation Management, which involves different ways of reducing the amount of solar radiation that reaches the Earth's surface.
The concept behind solar radiation management is fairly basic: introduce a substance into the environment that will reflect more sunlight back into space, and the resulting reduction in the amount of sunlight that reaches the surface will cause an immediate temperature drop in the affected region. One method of doing this involves spraying reflective aerosols — tiny drops of liquid about the same size as those that make up clouds, such as sulphur dioxide or titanium dioxide — into the stable stratosphere, where they can persist for years. Similar aerosols injected into any level of the troposphere (the lowest level of the atmosphere, where all weather happens) would quickly get caught up in the turbulent weather that we see every day and would not last long enough to help reduce incoming sunlight.
Would this really work? Studying the effects of volcanic eruptions (which is where they got the idea from in the first place) and using computer model simulations have given scientists plenty of evidence that it will.
Some approaches to solar radiation management have tried to deal with the situation on a global scale, with talk of releasing a million tons of sulphur dioxide into the stratosphere to lower the temperature around the world. However, these ideas have come under criticism, because of the potential for unforeseen consequences. For example, it has been suggested that introducing sulphur dioxide into the stratosphere could destroy the Earth's protective ozone layer, exposing us to dangerous ultraviolet radiation from the Sun.
Dr. Keith and his colleagues suggest that much better results could be achieved, with a minimum of risk, by only using solar radiation management on a regional scale. Therefore, rather than spread the reflective substance across the entire stratosphere, we would only use it over the area that needed it. They used a selected climate model to simulate these regional changes, compared to a uniform global change, and according to CalTech News, "it took five times less solar reduction than in the uniform reflectance models to recover the Arctic sea ice to the extent typical of pre-Industrial years."
Injecting just five metric tons of these reflective aerosols into the Arctic stratosphere could lower solar radiation levels over the Arctic Ocean enough to refreeze it and allow it to remain frozen. Before you get too alarmed by that five metric tons, the latest official figures from the US EPA show that in 1999, industry released over 17 million metric tons of sulphur dioxide into the troposphere.
There are down-sides to the plan, of course.
Likely no surprise to anyone, it is going to cost money. Compared to how much the effects of climate change are projected to cost us, or what the costs of reducing emissions will be, though, it is a drop in the bucket. Dr. Keith, along with Justin McClellan, from the Aurora Flight Science Corporation in Cambridge, Massachusetts, and Jay Apt, from Carnegie Mellon University's Tepper School of Business and Department of Engineering and Public Policy, published a cost-analysis report in the journal Environmental Research Letters, in August of this year.
Their report states that the technology to deliver these materials to the right altitude and location already exist, and by modifying existing aircraft to act as the delivery method, the entire effort of running the program would cost between $5-8 billion per year (depending on the method of delivery), with the majority of that cost going towards buying or producing the sulphur dioxide itself. According to the same report (referencing from the 2007 IPCC report) "the costs of climate damages or of emission mitigation are commonly estimated to be 0.2—2.5% of 2030 global GDP... equivalent to roughly $200B to $2000B per year. Our estimates of the cost of delivering mass to the stratosphere — likely to be the most substantial part of the cost of SRM deployment — are less than 1% of this figure."
So, we can do this, and compared to the alternatives, it is fairly cost effective. However, is this something we should be doing?
From the standpoint of the effect of having sea ice as opposed to not having sea ice, we should choose to have the sea ice. Without it, global temperatures will rise even faster than they are now. When the sea ice is there, it reflects back solar radiation into space and limits the amount of warming there is of the planet. Take that sea ice away and the darker water absorbs a large percentage of the incoming solar radiation. This will not only contribute to more melting of sea ice, but will give a generally warmer atmosphere and as the water warms it will expand, causing further rises in sea level.
There is the risk of destroying the stratospheric ozone layer, especially if these reflective aerosols get into the Antarctic stratospheric clouds that accumulate during the winter, which are the primary cause of the Antarctic ozone hole. These chemicals, in higher concentrations, would enhance the destruction of ozone and make the ozone hole even larger. However, using a regional scale approach would allow us to limit the concentrations of the aerosols, and thus limit the damage they cause.
There's one other problem with this idea, though — a general tendency towards quick fixes.
Peter Mooney, with Ottawa's Etc Group, which monitors the effects of technology and corporate strategies on society and the environment told The National Post, "It's naive to think that once [solar radiation management] becomes a political option that governments won't just take it on and interpret it as they wish. They will always find scientists who will give them the spin that they want."
"[We shouldn't be] opening up the back door for politicians to creep out of, claiming that, 'Don't worry folks. We don't need to do anything because we have technological fixes that we can deploy on short notice.'"
Photo courtesy: US Fish and Wildlife Service
New research from the Potsdam Institute for Climate Impact Research shows that global sea level rise is happening 60% faster than IPCC (Intergovernmental Panel on Climate Change) projections, even though temperatures are rising much as expected.
Potsdam's Stefan Rahmstorf:It contrast to the physics of global warming itself, sea level rise is much more complex. To improve future projections it is very important to keep track of how well past projections match observational data. The new findings highlight that the IPCC is far from being alarmist, and in fact in some cases rather underestimates possible risks.
So how fast are sea levels actually rising?
This latest research, based off satellite data so as to get more accurate readings and greater global coverage, shows that sea levels are rising on average 3.2mm each year—and not because of any temporary event like ice discharges from the ice sheets of Greenland or Antarctica, or because of internal variability in the climate system.
The IPCC has projected that sea level rise is happening at the rate of 2mm per year.
Photo courtesy: Derek Keats/CC BY-SA 2.0
I know that penquins are just possibly the cutest things that have ever waddled upon the face of the earth; but, saving the planet by loving them...seems like a stretch to me. But, not to Francois Blanchette.
Applied mathematician Francois Blanchette of the University of California at Merced was inspired by the fluid movement of penguins huddling from the cold in the hit documentary "The March of the Penguins." Now he hopes his work will inspire others, leveraging the power of penguin-love:Nearly everybody seems to love penguins and not enough people love math," he says. "If we use math to study penguins we could potentially teach more people to love math too!
Seeing a perfect opportunity to apply his skills, Blanchette and his partners -- Arnold Kim and Aaron Waters -- developed mathematical models of penguin huddling which demonstrate that a selfish strategy to minimize individual loss of warmth optimizes heat sharing in the penguin mass.
Initial models with simple assumptions such as constant wind and identical penguins evidenced the fluid movement of the huddle, slowly migrating to leeward as cold penguins on the outer edge seek a warmer spot away from the wind. But these simple assumptions evolved a longer, narrower huddle than is typically seen in nature.
Adjusting the variables a bit to account for wind eddies and penguin variations resulted in that rewarding "Eureka" sensation, the moment when a mathematician knows their work is correct because it "fits" -- in this case fitting the shapes and flows Blanchette has seen on film.
As is common with a Eureka moment, Blanchette found the awe and amazement that scientists seek when studying nature. Blanchette describes the new insight his models triggered: "Even if penguins are only selfish, only trying to find the best spot for themselves and not thinking about their community, there is still equality in the amount of time that each penguin spends exposed to the wind." Blanchette further notes that the animals-alone-against-nature aspect may be critical: "A penguin huddle is a self-sufficient system in which the animals rely on each other for shelter, and I think that is what makes it fair. If you have some kind of obstacle, like a wall, then I think it would stop being fair."
Blanchette's hope to inspire future mathematicians must not be in vain. These types of mathematical models, accounting for a large range of variables while predicting behavior observed in nature, will be critical in measuring, predicting, and reacting to global climate change as well as for managing a wide array of complex interactions between mankind and our planet's ecosystems.
Blanchette's research has been published in PlosOne: "Modeling Huddling Penguins".
View of Hurricane Sandy. Photo courtesy: NASA Earth Observatory/Public Domain
Once again, we've polluted our way into dire circumstances. This time we've managed to increase Hurricane Sandy's fury with our interfering ways. Global warming is responsible for an increase in the strength of Hurricane Sandy. Brian Merchant
of TreeHugger explains:
Hurricane Sandy is out in full force; I'm currently waiting for the slow-moving frankenstorm to bear down on me as I tap this out (good thing there plenty of memes to keep me distracted). As is to be expected, there's been some good discussion about how much of the storm is attributable to climate change — Lloyd (a fellow writer at TreeHugger) collected some of the best pieces exploring that link yesterday. And I've argued that humans have built a veritable frankenstorm factory by spewing CO2 into the atmosphere; now we have to figure out how to live in it.
But I thought I'd add some commentary from the horse's mouth; that is, some discussion of the climate-hurricane link directly from a climate scientist. Today, Slate published a Climate Desk interview with Dr. Kevin Trenberth, one of the nation's most esteemed climatologists, and here's how he explained the impact global warming was registering on Sandy:Most of what is going on with Sandy is weather, and there is a large chance element to it, but it is all occurring in an environment where the ocean is a bit warmer, the air above the ocean is warmer and moister, and that is fuel for the storm and especially adds to the risk of heavy rainfalls and flooding.
The predominant thing is hybrid storms are chance events. They are a crap shoot. With hurricanes there is a very strong environmental component to it. Hurricanes are very dependent on the environment. Therefore, changes in the environment modify the hurricanes. There are higher sea temperatures now, more moisture in the atmosphere, and there is a risk that the storm will be more intense and possibly a little larger ...
The thing that the climate is doing is that the sea temperatures are higher. There is more moisture feeding into the storm. That adds to the rainfalls. The rainfalls could be 5 to 10 percent higher as a consequence of climate change. The sea level is running a little bit higher. Sea level is going up a foot a century at the current rate. Over the last 20 years sea level has gone up 2 1/4 inches ... There are a lot of other aspects feeding into Sandy.
Read the rest over at Slate.
The point is clear, and it's one we've heard many times before. Climate change didn't "create" this storm. It's not responsible for this storm. But by spewing a century's worth of greenhouse gas pollution into the atmosphere, we've created an environment more amenable to nasty storms. We've warmed the air and the oceans, and we've spurred the sea levels to rise — sweetening the conditions for catastrophic storms like Sandy.
Stay dry, everyone.
The Woods Hole Oceanographic Institution's research vessel Knorr docked before its scheduled departure on Sept. 6 to study salinity in the mid-Atlantic ocean. Photo courtesy: Yahoo!News
Over the past 50 years, the salty parts of the oceans have become saltier and the fresh regions have become fresher, and the degree of change is greater than scientists can explain.
Researchers are heading out into one particularly salty ocean region, in the middle of the North Atlantic Ocean, in hopes of better understanding what drives variation in salinity in the upper ocean.
Ultimately, they hope, research like this will offer insight on the dynamics behind the dramatic changes in the ocean's salt content.
Many oceanographers have a hunch about what is going on; and, are not afraid to say so. The answer is climate change; and, Ray Schmitt, a senior scientist at the Woods Hole Oceanographic Institution, told journalists this during a news conference Wednesday (Sept. 5).
"Climate is changing all the time, and some of that change is due to natural variation," Schmitt said. "The 50-year trend we are talking about, most of us believe is really due to the general trend of global warming."
This matters because the ocean is at the heart of the planet's water cycle: 86 percent of global evaporation and 78 percent of global precipitation occur over the ocean, according to NASA, the lead entity behind the project, called Salinity Processes in the Upper Ocean Regional Study (SPURS).
Over the ocean, more evaporation as compared to precipitation translates into saltier water. Meanwhile, in regions where precipitation is favored, water is fresher.
By tracking ocean salinity, researchers can better understand the global water cycle. Global warming is expected to intensify it, but current computer models do not predict the amount of change seen over the last 50 years, Schmitt said.
Aside from an increase in evaporation caused by warming, such factors as winds can also contribute to changes in salinity.
"We have a lot of questions about the basic physics we hope to resolve with this cruise," Schmitt said.
In addition to instruments attached to the research vessel itself, scientists plan to deploy a variety of drifting, remotely operated and moored sensors. European researchers are also visiting the site and collecting data.
Salinity data is also expected to come from the satellite-borne instrument, called Aquarius, launched about a year ago, as well as the global network of Argo floats, which measure temperature and salinity.
The research vessel Knorr departed Woods Hole, Mass., for the mid-Atlantic Thursday (Sept. 6). The researchers will spend about three weeks deploying their instruments, leaving some behind for when they return. Due to hurricanes Leslie and Michael, the vessel's captain decided to travel quickly to the east and then south to miss the worst of the weather on their way to the study site.
The mid-Atlantic isn't the only area where researchers hope to study ocean salinity in detail.
"SPURS is named because spurs come in pairs," said Eric Lindstrom, a physical oceanography program scientist at NASA headquarters, explaining that researchers hope to do something similar in a low-salinity region, such as the Bay of Bengal or an area south of Hawaii.
While researchers think global climate change may be behind the changes in ocean salinity, changes like these are expected to have their own implications for climate. This is because ocean salinity also affects ocean circulation, and as a result, ocean temperatures, which have implications for weather.
Here's how it works: Compared with fresh water, salty water is heavier, and so more prone to sinking. Temperature has a similar effect, with warmth causing water to rise. Differences in salinity and temperature drive a slow-moving conveyor belt of ocean currents that encircles the planet. The Gulf Stream, which carries warm water across the Atlantic to Europe, is part of this conveyor belt.
It may work out that higher salinity in some regions counterbalances fresher water in others, Schmitt said: "It is a delicate balance and what we think now is it is not too likely the conveyor belt is going to shut down anytime soon."
August 2011 ended a summer that brought record-breaking and near record-breaking warmth to the U.S. and the globe. Photo courtesy: NOAA (National Oceanic and Atmospheric Administration)
As relentless heat wave has followed relentless heat wave across the United States this summer, conversations have increasingly turned to the role of global warming in extreme weather events. A new study solidifies the link.
Before 1980, excessively hot summers were practically non-existent. More recently, found a new study, summers that averaged 3.3 degrees Fahrenheit hotter than normal have become common – covering about 10 percent of land area around the globe each year – up from an average of just a few tenths of a percent in the 1950s, 60s, and 70s. In some recent years, super-hot summers have struck as much as 20 percent of the Northern Hemisphere.
Statistically, the pattern is too extreme to be considered a result of chance, found a new study, which pointed a finger directly at global warming as the underlying cause of the recent spike in extra-hot summers.
With projected warming over the next 50 years, the study predicted that summers averaging 5.5 Fahrenheit above normal will happen regularly. In a decade, nearly 17 percent of the globe will likely be experiencing scorching summers each year.
“The problem is that there’s always this caveat when people say, ‘Well, you can’t blame any individual event on global warming,’” said James Hansen, a climate scientist at the Goddard Institute for Space Studies in New York.
“But what we show is that you can blame this strong change in the bell curve (of temperature distributions) on global warming. And that change has really made a remarkable impact on the chance of the likelihood of extreme weather events.”
High-profile summer heat waves have fueled headlines around the globe in recent years. The historically hot summer of 2010 from Moscow to the Middle East was followed by a record-setting summer in Texas, Oklahoma, and Mexico in 2011. The summer of 2012 has already strained air-conditioners across the Midwest and eastern United States as well as parts of Canada.
Scientists often come up with meteorological reasons, including high-pressure systems and La Niña events, to explain individual heat waves. In an effort to see if there might be any larger trends, Hansen and colleagues analyzed seasonal temperature averages around the globe dating back to 1950.
When the researchers compared the period between 1951 and 1980 with the period since 1980, they found that average temperatures shifted toward the warmer in the latter period.
Even more striking, the team reports today in the journal Proceedings of the National Academy of Sciences, anomalously hot summers – defined by average temperatures that were three standard deviations or 3.3 F hotter than normal – became far more common in recent decades. Hot summers directly raise the risk of damaging wildfires and devastating droughts.
Overall, the study found, temperatures are becoming more variable with more extremes at both ends, making cooler-than-average summers likely to happen in the coming years, as well. Global warming also increases levels of water vapor in the air, raising the likelihood of extreme snowfall, rainfall, and flooding in some places.
Those kinds of patterns can be confusing to a public that tends to take global warming more seriously when they are living through unusually warm weather.
“We increasingly think that one of the biggest determinants of whether people think climate change is real or not, or whether they think it’s severe or moderate, is their relatively recent experiences with local weather,” said Barry Rabe, a political scientist who studies environmental and energy policy at the University of Michigan, Ann Arbor.
For the past five or six years, Rabe and colleagues have been conducting nationwide polls to gauge the public’s attitudes toward climate change. Their results suggest that concern peaks during heat waves and wanes during cooler-than-normal seasons.
Policy changes also tend to happen not when scientists announce a rise in global average temperatures, but when an area faces some kind of imminent threat that is related to climate change. An infestation of mountain pine beetles as a result of warmer winters in British Columbia, for example, had a direct impact on the creation of a major carbon tax there.
The new study, then, may come at an opportune time – as long as the weather remains wiltingly hot.
“Generally, in public policy and environmental policy, the thinking is that things have to be pretty significant and severe in a vivid way for people to become concerned and governments to react,” Rabe said.
“Normally, we have seen major policy changes follow some kind of disaster, he added. “One of the big challenges with climate change is figuring out what is the crisis, what is the burden of proof, and what is the demonstrable evidence.”
Photo courtesy: foam/CC BY-SA 2.0
Pollution from traditional cookstoves in developing nations, both indoor air pollution and black carbon soot's climate pollution, is equally a serious health issue and a technically easy climate fix.
Simply replace older cookstoves with more efficient new models that function essentially similarly but burn fuel more efficiently, resulting in less smoke and soot, as well as use less fuel, that's the reasoning. The case has been made many times on TreeHugger, and major international aid programs are underway, investing millions of dollars to spread newer, cleaner technology.
But, if a new survey of Bangladeshi women, published in Proceedings of the National Academy of Sciences, is more widely applicable then there's a huge uphill climb ahead for proponents of the cleaner cookstove climate and health fix.
It seems that even though 94% of Bangladeshi women surveyed know that the cooking smoke is a serious health hazard indoors (remember it's overwhelmingly women exposed to the smoke), they'd prefer to stick with traditional stoves and spend money on other aspects of their lives.
If given the option of a new clean cookstove or a cash subsidy, they'd take the cash and spend it on "doctors, schools, electricity, clean water, latrines, seeds for planting, and structures to protect their land from flooding."
Currently 98% of Bangladeshis use traditional cookstoves, fueled by a mix of wood and agricultural waste, and dried animal dung. The smoke from these stoves causes 50,000 premature deaths annually, part of 2 million premature deaths worldwide attributed to indoor air pollution. Outside the home, the black carbon soot from these stoves (as well as from industrial sources and older diesel engines) is a significant component of global warming, as well as increasing the rate of glacier melting as the particles settle on the ice reducing its albedo.
The survey found that even when the clean cookstoves were offered at a 50% subsidy, the rate of adoption only increased 12% for ones which burned fuel more efficiently and 5% for ones with a chimney. At full price the adoption rate was a very meagre 2-5%.
At least in Bangladesh, the draw of electricity, clean water, and a latrine (let alone what we in the wealthy world would consider adequate plumbing) are far bigger draws than either the threat of health problems from indoor air pollution or climate change — both, in the moment, theoretical problems with the effects felt non-immediately.
Photo courtesy: Dorothy Voorhees/CC BY-SA 2.0
Plenty of research has been done trying to calculate how ecosystems are going to be hit by climate change, how much productivity in a particularly ecosystem will change, but until now not so much on how extinctions and biodiversity loss will change productivity.
The bad news is that this new research shows biodiversity loss alone, if worst-case scenarios play out, would be as bad as the impact of climate change.
Report lead author David Hooper from Western Washington University says, "Some people have assumed that biodiversity effects are relatively minor compared to other environmental stressors. Our results show that future loss of species has the potential to reduce plant production just as much as global warming and pollution." (Science Daily)
Key word in the quote is 'potential'.
The study found that at the low range of projections for plant species loss (1-20%), the impact on ecosystem plant growth will be low in comparison to other environmental changes. In the intermediate range of species loss projections (21-40%), the effect is "comparable in magnitude" to climate change. At the high end of species loss however (41-60%), "the impact of species loss ranked with those of many other major drivers of environmental change, such as ozone pollution, acid deposition on forests, and nutrient pollution."
Perhaps all of that is fairly intuitive, at least at the high end (remove that much biodiversity and the impact is likely to be large), but now we have some sort of quantification of it.
Read the research: A global synthesis reveals biodiversity loss as a major driver of ecosystem change.
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