Wednesday, November 15, 2017

Digesting a study on meat and climate change

One benefit of writing a blog that no one reads is to be able to write at will. During my hiatus since the end of summer, I have been chewing on a lot of things. Interestingly, of all the things I bit, food seems the most nourishing for this post is about an article titled “Nutritional and greenhouse gas impacts of removing animals from US agriculture”. The full article from the Proceedings of the National Academies of Sciences is here.

The basic point it makes is that shifting to plant-only diet can meet our calorie needs with less environmental impact but will need supplementation of essential nutrients that are deficient in plant diets. This overall conclusion is completely intuitive and reasonable and not particulary striking. Also there are a number of limitations that the authors acknowledge themselves. Models are a simplification of reality and as a modeler  I don't know what it means to be one if I cannot see the limitation in any given model. So I am going to vicariously satisfy the pleasure I might have derived if I had been a reviewer of this manuscript.

But before I get to the limitations, let me say, there was one thought provoking insight buried inside. It is that while deriving calories and protein from meat is more land intensive, livestock production happens on relatively poor quality land and there is only a fixed quantity of good quality land suitable for crops. And so if we are to increase crop production to make up for the shortfall in meat, we have the tough task of growing crops on land not readily suited to farming and we therefore have to use a additional inputs - chemicals, water and technology to augment land quality, which will have it’s own attendant environmental implications. How big will this rebound in pollution be and how much will it offset the benefits of going vegetarian is an empirical question. This is a fascinating extension to this study worth delving into. Now, the concerns I have are the following.

First, I find the title of the paper misleading and inaccurate. The study is a descriptive analysis of the current environmental footprint of rearing animals for human uses. This is completely different from a predictive let alone prescriptive assessment of what would happen if we took any action to change the status quo. For small changes to the status quo, one can extrapolate from a descriptive analysis in a relatively straightforward fashion. However, small changes will have marginal impacts on the environment. LCA studies which are at the core of the claims  about GHG emissions in this PNAS paper cannot be extrapolated to derive the inferences that are implicit in this work. I am going reserve the more dry (i.e. methodological) details for another post. Clearly, the motivation of the authors is about informing actions that can bring about non-marginal or big changes. So object to the word impact in the title, a more apt title would be “Nutritional and greenhouse gas footprint of animals in US agriculture”

Second, agriculture no doubt has a big environmental footprint overall on the earth. However, greenhouse gas emissions are but one of the ways it negatively impacts the environment and agriculture is a much smaller contributer relative to fossil fuel use for non-agricultural uses. But agriculture is perhaps largest contributor to water pollution, soil erosion, flooding, human health impacts for farm workers, loss of biodiversity, etc. Indeed making agriculture more sustainable for these other reasons might have greater benefits, and of course, have attendant co-benefits for climate change albeit a purely climate focus might suggest different changes. In the current political and social climate, a strategy focused on tangible, immediate benefits might encourage people to incur costs that also have long term climate benefits. So it would be an opportunity lost if the wealth data this study has synthesized were not to be exploited to derive implications of a reduction in meat consumption for these other impacts and who knows we might find some trade-offs.

A third thing which strikes me is that there is no mention of ethics or moral implications of not eating meat or better less meat. It is fine for a scientific study, and by that I mean one that simply aims to explain and describe the state of a system leave out an inconvenient issues like  ethics and morality which cannot ignored in a normative context. However much the authors might try to be clear about the narrow scope and long list of limitations of their work, one can be certain that the vested interests, of which there is no shortage of, will exploit it to draw the wrong conclusions and obfuscate matters further. That is why I feel a focus on just GHG emissions is insufficient and could even prove counterproductive in the current climate. For instance, I am vegetarian and was raised so  for religious reasons. But given my beliefs, if I were not one, I am more likely to become one out of concern for treatment of farm animals and aquatic life rather than for the sake of reducing GHG emissions.

There is a lot of fascinating research now trying to ask people how they value the environment and what types of framing and messaging might nudge people in the direction of more environment friendly choices. That is why the awarding of the Nobel Memorial Prize in Economic Sciencest to Professor Richard Thaler for his work on Behavioral Economics is particularly timely. My take of behavioral economics is that misbehaviour is the norm and not the exception. That is people are people and people are not pre-programmed mechanical calculators. Back to the point, unfortunately, almost all this research in a sustainability context is focussed on only one set of activities such as electricity use, transportation choice, food or consumer goods. But I think we need to find out how people trade-off between making choices across these domains. Food, I think is incredibly complex and needs a truly interdisciplinary analysis because it is cultural, social, personal and less given to hedonic analysis, i.e. breaking down into attributes of calories, proteins and vitamins.  On the other hand choices for housing, cars and appliances is amenable to break-down of the value into attributes of cost, convenience, location, environment, etc. and we might have a easier task attacking each of these piece meal. Maybe I ought to drop cars from this list, something tells me taking cars away can be as touchy as denying meat, especially for those of us in America.

Sunday, September 24, 2017

Carbon tax in toddler speak

One of the positive influences of parenthood on me is the habit of reading. Yeah, I will admit I was never much into books. In spite of gentle nudging by my parents, I was more concerned about soaking in the sunshine and intense heat of south India playing street cricket. So I am glad to start by taking baby steps. In doing so, I believe I found the perfect story to explain a carbon tax to my 4 year old son. If you think about it, kids books are all about sustainability - they teach respect for all life forms, not wasting stuff and being good citizens and they make it sound like fun, as I think sustainability should be. Not an onerous responsibility. But really, I can’t think of one good reason to bother my son with understanding carbon tax.  However, I do think the same story can help explain a carbon tax in toddlers' terms to grown ups.

Anyway, the latest book we checked out from our wonderful public library is a story about a near-sighted giraffe. Spoiler alert, I am breaking the suspense of the story here. It is about a Giraffe that can't see very well but one who refuses to accept the fact. So when he bangs his head on a tree, he gets a helmet instead of getting glasses. When he bangs his foot, he gets boots. When he falls into a hole, he starts carrying a ladder. When he sits down on a thorny bush, he ties a pillow to his back. You get the point.

So when we adopt every conceivable policy but a carbon tax to address climate change it is akin to the giraffe refusing to wear a glasses. Let me complete the story. The giraffe’s friends after watching him refuse their good advice resolve to help him one way or another. So one night when the giraffe is sleeping, a panther (or may be another species of big cat) stealthily plants a pair of glasses around the  giraffe’s eyes. In the morning, when the giraffe bends down to take a sip of water from a lake, he sees his reflection and realises how clownish he looks with a helmet, boots, pillow and a ladder on him. He gets rid of them and realizes how elegant he looks in glasses.

Unfortunately, one cannot plant a carbon tax on a society as stealthily as the panther did with the giraffe. Indeed, government cannot do what private companies such as banks are able to do with fine print, and rightly so. Of course, there is also some truth in that the fine print is itself a product of a complex regulatory landscape. On the contrary, they plant stuff on us more brazenly, when they saddle us with debt due to needless wars and weaponization, expensive healthcare etc. But I digress. So the experts need to find new creative ways to impress upon the citizenry and policy makers why a carbon tax is the elegant solution to carbon pollution.

Maybe I am putting the cart before the horse for I am working on the assumption that carbon pollution is a problem, which unfortunately is a big assumption for an unbelievable large section of american society.

Thursday, August 31, 2017

(S)Peaking of oil


"The report of my death was an exaggeration" - Mark Twain

The stimulus for this post is this interesting talk by Tony Seba, and predictions about peak oil that I heard at recent workshop on transportation. I don’t have any materials to share from the workshop but this WSJ article presents similar points. Seba’s talk is mainly about the confluence of five major innovations - four technological - solar PV systems, battery technology, electric vehicles, autonomous vehicles and a fifth that is more institutional (academic jargon for business model), which is the ride-hailing industry (lyft, uber etc.) In fact, I had similar and optimistic yet different take on the combination of EV, AV and ride-hailing a year back.

Predicting peak oil, on the other hand, is a different proposition altogether. It has been a topic of intense analysis and debate for several decades now. Beginning with King Hubbert in 1950s, many geologists have been pessimistic about the long term prospects for cheap oil supply. Here is a link to a fascinating article in the magazine Scientific American from 1998. Peak oil claims rests on assumptions about depletion of reserves of "conventional" oil and the increasing amounts of energy (and therefore, cost) associated with extracting from depleted wells. Interestingly, economists were more optimistic and in any case the peak is not  important in and of itself as we would innovate our way out of the problem as oil price, the true indicator of scarcity, rises. And, of course, all the while climate scientists and environmentalists have been shouting (unforuntately, in vain so far) for absitnence, (ofcourse, from oil for the most part but not exclusively). But the peak oil prognostications of today are about an impending peak in the demand for (or more precisely consumption of) oil as opposed to peak due to depletion. The reason for this is exactly the kind of breakthroughs mentioned above.

If your day is made, then I recommend you read no further for I am going to spoil it. Sorry, but it is my job to call it as I see it. Don’t get me wrong. I would love nothing more than to solve externalities (jargon for pollution problems) and produce public goods (jargon for things like knowledge) with a business as usual  approach. But I know enough to not bet on it. In other words, I am not sure which among the two — peak oil supply or peak oil demand is better for the environment. 

A peak due to scarcity would mean that oil prices rise which would provide an impetus for renewables (which are costlier today because we do not see the full cost of oil) and at the same time make us more efficient in energy use. The flip side is that higher oil prices would also lead to innovation in finding more oil or converting coal and gas to liquid oil which is a very dirty process. It is a question of which of these two forces will win out. A peak in oil demand while it sounds good might be the proverbial Torjan horse. It might lull us into a sense of lazy optimism only for oil to strike back with vengeance. Here is why. 

1. Peak oil demand means that the price of oil keeps falling. At today’s price of $50 per barrel, we are all not exactly rushing to buy electric cars (of course, a few have plonked down $1000 to reserve a Tesla Model 3). As if life was not hard enough at $50/bbl, these technologies will now have to compete with ever cheaper oil. Likewise, solar and wind have to compete with ever cheaper coal and natural gas as we move to a renewable electric grid. 

2. Some contend that we did not stop getting around in horses because we ran out of them but that we discovered a superior alternative in oil and motorized transport. Other somewhat more trivial analogies might be that we did not run out of Kodak cameras, telephone lines, postal mail. In each case the product that displaced these were clearly superior and it did not take a government regulation to phase them out. There was also the famous Ehrlich-Simon wager about scarcity of important metals we know how that was settled. In any case, I am not convinced that batteries, solar electricity and electric cars are relatively as superior to today’s oil + internal combustion engines as oil was to horse drawn carriages. Agreed, an EV might be a smoother ride and range is unlikey to be an issue but is that nearly enough? Also autonomous and ride-hailing work is indifferent to propulsion technology.

3. Now, let me get off my smart horse and concede for a moment that EV’s and solar electricity are such a superior alternative that we will voluntarily stop buying internal combustion engine automobiles and combusting coal and gas. But that doesn’t mean the fossil fuel industry will shut shop and things will be hunky-dory. A bit of history would come in handy here. Before the 1970s, a substantial amount of oil was used for electric power generation and mind you burning oil for electricity is quite bad for both human health and climate change. This wasteful use of oil has since declined only because oil became scarce enough to justify it’s use only for transportation and as a source of back up and peak electric power and remote locations with little access to other energy sources. That said, in oil rich countries like Saudi Arabia oil is used profligately for baseload electricity. My spreadsheet tells me that at $20-$25 oil, oil-fired generation could come back in a big way especially in places where gas is scarce and coal is considered as dirty. What’s more at these prices we oil-fired generators might be able to afford $40 to $50 per tonne for either a carbon tax or carbon di oxide capture and sequestration.

I will conclude on a constructive if not entirely cheerful note. The solution is simple. Basically, we are faced with a leaky bucket and as we begin to fill it with cleaner water, it is all the more important that we also fix the leak. In technical terms, we need to put a price on pollution and make it not worthwhile to consume dirty fuels even as they become cheap. One way to do this is for the world to agree on capping global greenhouse gas emissions. I am optimistic that we will achieve this someday but will it be soon enough is anybody’s guess. In the meantime, there is no reason to not be excited about the coming technological disruptions.

Wednesday, August 23, 2017

Amazon and the urban landscape

Writing this blog helps me get something more useful out of my addiction of consuming news, which gets depressing by the day. But Professor Hal Varian himself thinks the best place to find ideas for research is the news and popular press rather than academic journals (link to his paper). So the idea for this post comes from a discussion on NPR a while back (link). It was on the unintended consequences of Amazon on cities. This reminded me of my own and only appearance on public radio till date (link) from about a year back talking about a related topic.

I work on LCA, which is largely, although not exclusively, about assessing the greenness of individual products or actions such as shopping online and more importantly, how does this compare to an alternative way of satisfying the need in question. LCA is not very meaningful in an absolute sense, it is only in a relative sense, i.e., when comparing alternatives. And so I have thus far only thought seriously about adding up all the pollution when you shop online vis-a-vis from a brick and mortar store. But this NPR program raised some really interesting and challenging issues both from an LCA and an urban sustainability standpoint. Online shopping is slowly but surely changing our landscape. For one, it is driving several types of retail stores to close down and this includes individually owned and outlets of large retail chains. Somehow, we tend to feel more badly about the former although the lives of employees in both is affected. At the sometime there is a boom in restaurants and bars (See this news article). It is hard to say how much of this because of rents being lower which is in turn driven by store closings, and how much is simply because of increase in demand for eating out and drinking. The two might not be unrelated. Amazon and online shopping is driving store closings and also freeing up money to spend on eating out.

So how do we begin to grasp the environmental impact of online shopping when there are all these ripple effects? LCA has a role here but this is a classic question for interdisciplinary research for understanding the environmental impacts requires a grasp of the economic implications. A great topic for research.

Tuesday, August 22, 2017

LCA and the world’s 28th largest economy

This has to be one of my best summers across the last seven years. I no longer have much control over whether I keep my job. It might sound terrifying to leave your fate in others’ hands but I am more relieved than worried at this point. So faced with a choice of writing blogs vis-a-vis bread and butter academic papers neither of which anyone seems to read, I choose the former as it is more fun and something even my family might enjoy someday. On that note, my tennis has seen a massive improvement this summer, thanks entirely to my father-in-law, a fine tennis player (you guessed right, my wife will be the first person I will be emailing this post). Let me get to the point. This post is about the environmental sustainability of the 28th largest economy in the world. These last two statements are not as disjointed as they might appear because I purchased my tennis balls from the latter. If you thought I am talking about a country, you are wrong. I am talking about Walmart, which is the largest corporation in terms of annual revenues (~$486 Billion in 2016 - the next largest corporation’s revenues were less than half that). Yeah, much to the chagrin of some of my environmentalist friends, I do shop there whenever convenient, which is not all that seldom. Therefore, when I came across this NPR report about sustainability at Walmart, one that fundamentally entails a life cycle assessment (LCA) of an entire corporation, I could not but go bananas. Incidentally, Walmart sells a billion pounds of bananas each year. A government mandate for each and every product retailed at LCA of Walmart would be akin to a full employment act for LCA experts. I digress. Walmart has a voluntary goal of reducing it’s GHG footprint by a billion tons between now and 2030, called Project Gigaton. When in a cynical mood, I would call voluntary a euphemism for cheap and empty but in today’s climate (pun intended), where the world’s richest and most powerful nation has abdicated it’s committment to sustainability, a pragmatist can ill-afford to be dismissive of corporate charity. When optimistic citizens, NGOs and not-entirely-insincere executives are stepping up  to the challenge, academics are obligated to descend from their ivory towers and play a constructive role.

Imagine you are Walmart’s sustainability lead. Ignoring for now the cold-hearted considerations of the dismal science (i.e. Economics), just think about where would you look to reduce your corporations’ overall climate footprint? If the government mandated a cost benefit analysis of what is the right level of sustainability that Walmart should seek that would be akin to a full employment act for both economists and LCA experts. I digress again. If you had asked me to guess which activity of Walmart contributes the most to it’s aggregate climate footprint my top two choices would have been, energy use at their warehouses and emissions from transportation and logistics. I am of course ignoring the emissions associated with the durables such as air conditioners or furnaces for which the bulk of life cycle emissions are during their use phase i.e., they depend on how fickle-minded and lazy consumers operate them, aspects over which Walmart has no control whatsoever. Ofcourse, Walmart could try to increase the sales of greener versions of these durables such as energy star appliances but that is a whole another topic.

So it might come as a bit of surprise that it is neither Walmart’s own energy use nor emissions during transportaiton that were the largest sources of emissions. Instead, it is the production of fertilizers. So how does urea make Walmart stink even though neither it’s production nor sales are central to Walmart’s bottom-line?  Enter LCA. An assessment of the supply chain emissions, effectively a form of LCA, of the various products retailed at Walmart appears to show that it is fertilizer use on farms that produce the grains that go into the meat and dairy products that go into the procesed foods that Walmart sells are the culprit. So Walmart has to convince the processors who in turn buy the grains, dairy and meats to clean up their act. Unlike with life cycle emissions from durable goods, Walmart can exercise substantial influence over the products they put on their shelves or more importantly on their website.  That is tough but not impossible task for Walmart. But I am glad to see that my trade is stepping up to the task and I look forward to teaching it again this Fall!

Tuesday, August 15, 2017

Getting a faculty position with an interdisciplinary PhD training

For teachers, summer time is travel time (Yes, poorly paid teachers have no choice but to travel during the most expensive times of year!). Summer is also the time for many academic conferences, workshops and meetings, at least many of the ones I frequent. I did my bit to boost the economy and warm the earth. Just last week, I got to attend a unique and highly satisfying workshop. It was a NSF Workshop on Interdisciplinary Urban Sustainability Careers at the University of Minnesota. The theme was - Now That I Have an Interdisciplinary PhD in Sustainable Urban Systems, What’s Next?. The workshop had panels dedicated to careers in academia, industry, government etc. I, ofcourse, was on a panel focussed on how to land a job in academia as an interdisciplinary PhD. It was a lot of fun and a wealth of information for students interested in both an interdisciplinary graduate education and career. I have been told there will be a link with the video recordings which I will share as soon as I get the information. In the meantime, I wanted to blog when it is still fresh in my mind.

Below are the questions I was asked to speak about. I did not get to convey this verbatim but basically this is what I had to say.
  1. What drew you to a career in academia? 
    • When I began my PhD, I thought I will join the non-profit/non-governmental sector or work in a government agency. That was still the case by the middle of the 4th year of my PhD. However, in my fourth year a slew of things happened that first kindled and eventually made a faculty position as my first choice for a career. I authored a couple of publications that instantly received a whole bunch of citations. I was also invited to guest lectures, workshops and international consultations on biofuels - the focus my research.  While I had been a TA before, I actually got to be a co-instructor for an interdisciplinary class freshman/junior class called Plants and Society, which was  a lot of fun. Finally, I also got the chance to help write grant proposals. 
    • Secondly, it was option value in the face of irreversibility. I felt and still feel it is harder to find a faculty job after working in non-academic jobs rather than the other way around. Ofcourse, there are exceptions. If you worked in National research labs, some private research labs or even the government you might be able to find academic positions but those are fewer and when I see the openings for and applicants it is mostly freshly minted PhDs and post-docs. So long as you are doing high quality research and have good writing skills and communication skills, you are likely to be competitive in academic market.  But you will be swimming against the tide.
    • Lastly, as an immigrant, an academic position can fetch you a permanent residency quickly and it did for me. I hope that is still the case today. In today’s political climate that is gold.
    • Today however, the thing I value to the most is the total freedom to pursue your passion, speak your mind, and the flexibility of working during your own time except of course, when I have to teach. Also it is extremely satisfying to hear students tell you how much they enjoyed your class and that you motivated them to continue in this line further. These more than compensate for the lower wage when compared to private sector career. 
  2. How did you frame your research and experience when you were on the job market? 
    • I was in a situation of having published a couple of papers. In such a situation you have a couple of options, present one of the papers or a weave a story around the papers. The risk with the former is that it is the standard approach in disciplinary job talks and you might come across as not having breadth. The risk with the latter is that you might come across as shallow as you run through two or three different papers in 40 minutes. So it is a really tricky situation.  I was fortunate that the topic of my research -  the environmental implications of biofuels — was then a hot new topic. I focussed on one specific paper, that would take three more years to publish, but I also gave a brief overview of my other papers. Having a publication or atleast an almost final manuscript is critical. This is also essential to make the initial cut from 100 odd applications to a select 10 to 20 that will be more closely reviewed say via Skype and eventually the 5 or 6 that will be short-listed for a site interview.
  3. How did your interdisciplinary research experience help in the job hunting process? 
    • Quite a lot. For one, I went to an interdisciplinary program and so I was acutely aware there is a perception issue to overcome. 
    • My PhD committee had an engineer, physicist, agricultural economist and water economist and that was a great preparation. 
    • Our own department PhD seminars and department seminars were a great preparation with people from different disciplines asking all kinds of questions of a presenter.
  4. What is the most challenging aspect of navigating the job hunting process? And how did you overcome it? 
    • Clearly communicating who you are  especially when you have an interdisciplinary PhD that no other institution offers.
    • There is also a disadvantage. A lot of disciplinary people might compete on the interdisciplinary market but the otherway around is more challenge as there is a perception issue to overcome, when you want a job in a disciplinary department but you don’t have a PhD in that discipline.
    • You will not be able to send a canned application that you mail out to tens of openings, each has to be tailored for each interdisciplinary job could be different.
    • Contact the programs you are applying to and speak to a search committee member and get a sense of what they are looking for and if it is worth your time. 
  5. Looking back, what would you do differently?
    • Not much. Why tinker with something that seems to have worked well. I will know for sure next year :-)
  6. How do you handle the workload and life/work balance during the first two years as an assistant professor?
    • Depends on your personality and life situation. You have 6-8 years to tenure, don’t rush it. Use the clock. Ease into the job. Don’t get burnt out. Get your grad school/post doc papers out of the way and put together the class materials for what you want to teach. Get to know the place you have moved to. Important to find a good mentor at work not necessarily one who works in your area but one who can help with navigating the tenure process. Lastly, and most importantly, there may be important personal and family decisions that for some can wait until after tenure and for some it cannot. I am one to put family first, and for me that has totally changed my view of sustainability.

Closing Thoughts

  • I was fortunate to be accepted to a top PhD program. I was fortunate to find outstanding advisors, late Prof. Alex Farrell and Prof. David Zilberman. I was fortunate that the topic of my research was timely both in a policy and academic sense. So I have had my share of good fortune but it also just did not land on my lap! It has been, is and will be a lot of a struggle whenever you attempt something outside of mainstream. 
  • Academia is an institution steeped in disciplinarity. While it is changing it is a slow transformation. Expectations are that you have some solid disciplinary foundation and demonstrate an ability to bridge disciplines. 
  • This is important - there is no single template to success - you have to be creative and imaginative and that is where the fun is. You will be evaluted by smart but disciplinary experts who quickly need to understand who are you and what is your skill set. There might be no single discipline, single journal, single academic society that you can point to and say you are that person. It is your job to communicate clearly what is your unique skill and how it can be applied beyond your dissertation work, to attract students to work with you, to attract funding for research, etc. At a minimum you should be an expert in atleast one research method and a have a good grasp of the basic theoretical concepts needed for your work. 
  • You got to embrace skepticism about your work. Believe me, there will be many days when you wonder, I wish I was just an engineer, chemist, ecologist or economist. But if ask you me it is worth failing challenging established norms rather than walk a well worn path. If I were do it all over again, I will choose an inter-disciplinary PhD again.



Wednesday, April 12, 2017

Less meat and more miles or More meat and less miles?

This post is because of this report. It summarizes a study on on the environmental impacts of conversion of mangroves for agricultural uses -  raising cattle and shrimp farms. It quotes ""On a personal scale, this means a typical steak and shrimp cocktail dinner produced through mangrove conversion would burden the atmosphere with 1,795 pounds of carbon dioxide," said J. Boone Kauffman, an ecologist at Oregon State University who led the study. ... This is approximately the same amount of greenhouse gases produced by driving a fuel-efficient automobile from Los Angeles to New York City." "

Let's first dispense with the obvious. Of course the answer to the question is neither as less meat and less driving is the more sustainable choice. To me sustainability is more about  like Haile Gebrselassie rather than Usain Bolt i.e.,  winning a marathon rather than a 100m dash. So let's focus on making one adjustment at a time.

There is a neat paper co-authored by the late Dr. Lee Schipper, who made great contributions to transportation sustainability. And some of the most telling number from his study is the picture below


As someone whose single biggest impact comes from air travel, I felt better that the airline industry has made great strides in reducing the GHG intensity. If you read the paper, this is attributed to fuel economy, and regulatory changes and higher occupancy per flight. Also rail travel is getting better but in terms of the passenger miles traveled in the US it's absolute impacts are likely smaller relative to road and air travel.

But let's just focus on grub and gas (I mean gasoline, not the product of the former).  So while the statement that a single meal involving steak and shrimp might have more impact than driving a car several thousand miles is striking, most people are not considering driving from LA to New York, which is about 2800 miles. So let me interpret this as equal to about a fourth of the annual miles the average american drives each year.

Now, let us crunch some numbers to compare the effectiveness of reducing meat vis a vis reducing vehicle miles traveled from a greenhouse gas perspective. I am using the assumptions below for protein, which come from this study. Emissions per mile of auto use are based on EPA reported fuel economy (harmonic mean of 50% city and 50% highway miles)

A few additional assumptions about the base line relative to which some adjustments will be compared:
Protein intake
Daily protein requirement for adult: 60 grams (gm)/day
Baseline protein mix:  45 gm of beef protein + 15 gm of chicken/milk protein + 0 gm legumes
Automobile:
Average annual vehicle miles (U.S.) - 12000 miles/year
Automobile for the base case - Ford F150

Below is the effectiveness of four different adjustments relative to the baseline

Reducing beef protein intake by 10% is as effective as driving 5% less miles using a F150. Switching to a Camry is four times as effective as each of the other adjustments shown. It is for oneself to decide which of these adjustments is easier. Of course bigger adjustments, combining more than one type of adjustments or different baseline assumptions will all affect the calculations.

Bottomline: There are any number of calculators to estimate your energy, water, CO2 footprint etc. But I have not come across a calculator that combines our various activities and various types of burdens and gives information about the effectiveness (say, on a % emissions basis) of adjustments along different fronts (food, travel, housing, etc.) and in terms of changing the equipment (or capital stock) vs usage and let the consumer make better informed decisions.




Monday, April 10, 2017

Comparing apples and oranges - a life cycle assessment perspective

I am excited about my large LCA class this year. I am not sure if it was the subject matter itself, my teaching or my grading last year, that lead to an almost 20% jump in the demand for my 2017 spring LCA class from around 55 last spring to 67 this time around. Assuming a few people drop out by Week 2, which again I cannot tell whether it was the subject matter, my teaching style or the painful HW1 which I handed out, I think it will settle at 60. This would still be a 17% increase from the 51 students that stuck with me for all 10 weeks last spring. I do feel bad that I could not accommodate several more students who wanted to enroll and might have stayed on.

In any case, I introduced some noise into the above calculations because, I changed my introductory lecture. Keeping with my resolve to make sustainability more fun, I started off by talking about food, movies and sports, things I love to no end. Yes, I am an academic but I am not ashamed to admit it is not math, science or reading books that really keep me up! I hope my colleagues who are going to be voting to give me a permanent job and my references who are going to be writing me letters of support read just my academic work rather than my blog! But if they do, I hope they see that my perspective on sustainability research is that it needs a new perspective, one that moves it away communicating it as being morally and ethically right to also being an exciting and enjoyable pursuit. But this blog is just for myself, my students, broader public (wishful thinking!), and some day my family. 

You are not sitting in my class and so before you click away, I really should get to the point of this post. I began the first lecture by talking about nutrition labels and what is good, bad and confusing about them. The basic point I was trying to make is that doing an LCA is like trying to come up with a nutrition label, except that it is dominated all by the bad things associated with consuming a product. I was quick to clarify that the students will not merely become good label makers at the end of the quarter but have picked up on really interesting insights when it comes to designing an LCA study and using the information derived to make important decisions. However, in between comes the really important yet painful task of accounting. (Talking of accounting, I spent my entire weekend doing my taxes. I must say it was painful but in the end I am happy I determined my effective average and marginal tax rates at the federal and state-level. If only there was Kayak like comparison one could do with your tax that compares 10 different sites. I know that might be crazy, more on it on a separate blog post perhaps!)

I keep getting distracted, back to the point about the proverbial apples vs oranges comparison that is used and abused. I say abused because, apples and oranges are  really not that different if you look at their nutrition content. Check this out. But I found this out just as I am writing this blog and I ended up abusing the comparison anyway. Next year will be different. However, the fundamental point about LCA I wanted to get across that it is really important is that before we start comparing choices from a sustainability standpoint, we really need to be sure what it is that we are comparing. And when you look closely, the problem is nightmarishly complex. There is hardly anything that we consume that is a like for like comparison. In class we discussed, how it is hard to compare a bowl of rice vs corn, a gasoline and electric car, plastic vs paper bag, nuclear vs hydro power, etc. After that I threw in a question about how does one compare golf and football (I mean the real football, but it doesn't matter). 

A fundamental technical concept of LCA is the notion of a functional unit. We really want to be comparing substitutes that are "functionally equivalent". What I mean is, that we consume goods to meet certain needs, which are the functions that the good serves. From this perspective, one might say the function of a bowl of cereal is to provide calories, for a car it is taking you places, the function of a bag is to help carry stuff, the function of an electric power plant is to supply electricity. However, it is not so simple, and thankfully so, because otherwise, my job would be so much more boring. Here's why. Cereals or any food for that matter not only provide calories but also proteins, vitamins, fats etc. as well, and no two substitutes seem to have the same proportion of each. Likewise, a gasoline and electric car differ in their driving range and so are not directly comparable, at least not today! Paper and plastic bags are not comparable unless you normalize them for their differential capacity in terms of volume or weight carrying capacity, reusability, conformability or ability to carry wet products. Finally, nuclear and hydro power plants both produce electricity but hydro power might not have the same reliability as nuclear in dry years! You get the drift. 

Now to some fun thought questions. At the risk of making my life harder by revealing important exam questions, how might one go about comparing the following if asked which is more sustainable
1. DVD vs Netflix vs Cinema
2. Home vs restaurant meal
3. Jean vs polyester trousers
4. Starbucks vs Peet's coffee stores (a comparison of the stores itself and not simply a cup of coffee)

A hint about the last comparison, which are two places I frequent. My local stores of each appear considerate of  the poor, and likely, homeless people who come hang out (indeed, some of them do buy a drink or food) and this is really heartening for me to see, but the former seems to attract and tolerate more of such people. That said, I am a patron of both places. So the coffee stores from my perspective functions as a place to eat, drink, and hang out, in some case the only nice place for the poor. If a place was less kind to the poor then perhaps I will want to take my business to a place that is more considerate!

If you think these are mere academic comparisons and the simple answer we need variety and so need a mix of products, you are absolutely right. But still there is the question, if I had to consume one more unit of each, what would that be! In the time, chew on whether apples and oranges are that different!













Tuesday, March 28, 2017

An unintended (positive) spillover of the US elections for my trade (LCA)

Life cycle assessment (LCA) is framework for quantifying all the various types of environmental burdens (green house gas emissions, the different criteria air pollutant regulated by the EPA (particulate matter, photochemical oxidants (including ozone), carbon monoxide, sulfur oxides, nitrogen oxides, and lead)numerous other hazardous chemicals, water pollutants, water depletion, fossil fuel consumption etc.) associated with the consumption of a given good (such as electricity, gasoline, or a pair of jeans) or activity (such as driving, having a meal or shopping online). 

I am passionate about LCA because this passion is ultimately driven by a desire to have a positive impact on our environment, and of course, the lives of fellow human beings. And so while I would like to see more public and private interest in LCA, if our policy makers did their job well (sadly, the exact opposite of what happened today!) the need for LCA might actually decrease, but I will be totally fine with that. Let me explain why

Because LCA is about specific products whereas the pollution is associated with each and every product or service we consume, LCA can be a complicated and costly way to improve environmental outcomes. For instance, how is one to determine, if and at what cost are we impacting the environment simply by changing our consumption of one product using LCA. No single product might be superior when you take all the various different types of burdens mentioned above into account. On the contrary, if the whole world took global warming seriously, of course, (the US is a big culprit here) and we had a global policy for what is a global problem then we need not worry how much carbon emissions come from driving a small car vs a bigger car, a gasoline car vs EV, or driving vs public transit etc. Likewise, if we took each different type of environmental burden seriously and had the best policy in place for each then we don't have to worry about the impact of each different decision for the products in the market would reflect the true cost of each. This is of course policy utopia.On the contrary, america has voted for ushering in dystopia, at least from an environmental standpoint.

Fortunately, there is a large section of this society (in fact a majority of American voters) care about our environmental footprint. So what actions might these enlightened sections of society take that can help overcome obstacles at higher level of government? I feel that LCA has become an ever more important lens and tool to help identify what actions, individual consumers and firms of course, but more importantly city administrations and state governments could take such without federal support. So while purely from an environmental perspective things might seem gloomy, I am looking forwarding to applying my trade in the coming years!


Wednesday, March 22, 2017

Scientists and engineers are pulling their weight but may be the rest of us aren't?

I produced the chart below for a formal talk and I called it the green choice gap (actually, the credit for suggesting this phrase goes to Prof. Peter Kareiva, the Director of my Institute). It shows that the best EV today is about six times more efficient in converting fuel to distance travelled relative to the average car on the road today.  But in plain speak, I interpret it as may be scientists and engineers are doing their part to help make personal transportation more sustainable but it is the rest of society that is shirking. Perhaps I am letting the scientific community get off too easy for one could easily point out perhaps that the initial cost of EV's still much higher for most people to afford it. And that is an excellent come back. No refuting that. But sitting on our back expecting science and technology to deliver EV's and other cutting edge technologies for the same "artificially" low price as dirty and mature technologies is not smart either. So much of my current energy is focussed on identifying new ways to encourage the adoption of EV's (and other similar investments i.e., clean and efficient but high upfront cost) that do not involve oft-repeated recommendations by academics such as pollution tax,  clean vehicle subsidy or various types of regulations and most recently nudges.