Wednesday, February 25, 2009

Fuelling the future

In the latest issue of Momentum, a new magazine out of the University of Minnesota, I argue that "our cars aren't alone in needing a new diet". Here's the opening:

It’s been a tough couple of years for the public relations staff in the biofuels industry.

The production of biofuels from crops like corn has been blamed for everything from driving up global food prices and deforestation in the Amazon to depleting oxygen in the Gulf of Mexico (not to mention raising the price of tequila).

Even the basic purpose of today’s commercial biofuels production has been called into question.

A study by researchers at the University of Minnesota, published last year in the journal Science, found that if previously undeveloped landscapes are cleared for biofuels production, then those biofuels emit more greenhouse gases than gasoline and diesel. Policymakers and the public are now asking if it’s efficient or ethical to use croplands to feed machines rather than people.

There’s one obvious place to look for an answer. In North America, we have been feeding the majority of our crops to machines for decades. These elaborate, protein-producing devices are best known by their common names: cows, pigs and chickens...

Click here for the full article. Or continue after the jump.

Eating animals is hardly new. Our nomadic hunter-gatherer ancestors relied on meat for a large proportion of their protein intake. But the advent of agriculture and rise in population after the end of the last ice age led humans to settle in villages and shift to a more energy-efficient, grain-based diet. Over time, meat would be reserved for those who could afford the land and workforce required to raise animals.

Diets in the developed world changed again with the discovery of fossil fuels, especially oil. This cheap source of energy allowed us to produce nitrogen fertilizers, transform crop genetics, fuel agricultural machinery and transport agricultural products around the world. Buoyed by high crop yields and newfound agricultural wealth, we began feeding large quantities of grain and oilseeds to our farm animals.

Today, the average American eats as much as 275 pounds of meat each year, up from 197 pounds in the early 1960s.

Feeding the literally billions of cattle, poultry and pigs now requires a large proportion of the world’s—and mainly America’s—croplands. More than two-thirds of the American corn, soybean, sorghum, barley and oats harvest is used to produce animal feed. That’s more than two-thirds of the fuel used to operate machinery, more than two-thirds of the agricultural chemical use and subsequent water pollution, and more than two-thirds of greenhouse gas emissions from croplands.

In the coming decades, the demand for both animal feed and transportation fuels is expected to rise sharply as Asia and the developing world become wealthier. According to the Food and Agriculture Organization of the United Nations, per capita meat consumption in China has doubled since 1990, and it could double again.

Can our agricultural system meet this increasing demand while also reducing greenhouse gas emissions, tropical deforestation and water pollution? The solution may be switching to more efficient machines.

Like the cars we drive, the animals we eat have wide-ranging efficiencies. Beef cattle are the SUVs of animal agriculture. Renowned energy expert Vaclav Smil calculated that the U.S. agricultural system uses 32 kilograms of feed to produce 1 kilogram of edible beef. Poultry is the fuel-efficient compact of the animal world, with around one-eighth the feed ratio of beef.

The good news is that Americans have been slowly shifting their diets from beef toward more efficient forms of food production. Since the 1970s, per capita beef consumption has decreased 20 percent, while per capita poultry consumption increased by 40 percent. And more and more Americans are forsaking beef or all meat out of health concerns.

A more aggressive move toward poultry, dairy and vegetable-based diets could greatly decrease the land, energy and fertilizer needed to feed the population. In turn, this change would decrease direct greenhouse gas emissions from food cultivation and nutrient pollution to waterways. My own research indicates that reducing beef consumption in American diets would also reduce nitrogen pollution in the Mississippi River and shrink the dead zone in the Gulf of Mexico.

Changing diets would also free up productive croplands for cultivating second-generation biofuels based on unfertilized grains, oil crops or grasses. This newly available land would help eliminate concerns that diverting productive croplands to biofuels cultivation causes the clearing of native vegetation and the release of stored carbon elsewhere in the world.

In a carbon-constrained world, food efficiency may be just as important as fuel efficiency.


Sunday, February 08, 2009

Levelling the science of sea-level rise

One of my biggest pet peeves with the climate change communication world is widespread use of sea-level rise ‘maps’. There are countless maps and animations out there. Think the simulated flooding of New York in An Inconvenient Truth or, for a local example, the Sierra Club’s post-Greenland map of Vancouver in which my home becomes coveted waterfront property. Anyone with a digital elevation dataset and some GIS skills can draw a map of what land will “disappear” if the sea level rises by 6 m, or 6 km for that matter.

Leave aside for now the uncertainty about future rates of sea-level rise, the usual beef with graphic representations of sea level rise. Spend a few weeks in a coral atoll and you’ll know the real problem with these simplistic graphics. The sea is not actually level. And there’s no scientific reason to think that the rise will be.
A part of this issue is tackled in a terrific new paper by Mitrovica et al. in last week’s Science.

The paper estimates the regional variation in sea level rise that would occur from the melting of the West Antarctic Ice Sheet (WAIS). Unlike the brute force mapping exercises, Mitrovica et al. consider the actual physics of the ice melt, including gravitational attraction of the ice sheet, migration of shorelines and the effect of all that ice on the Earth’s rotations. For example:

The rapid melting of ice sheets and glaciers leads to a sea-level change that departs dramatically from the assumption of a uniform redistribution of meltwater (4). An ice sheet exerts a gravitational attraction on the nearby ocean and thus draws water toward it. If the ice sheet melts, this attraction will be reduced, and water will migrate away from the ice sheet. The net effect, despite the increase in the total volume of the oceans after a melting event, is that sea level will actually fall within ~2000 km of the collapsing ice sheet and progressively increase as one moves further from this region. Each ice reservoir will produce a distinct geometry, or fingerprint, of sea-level change... Although the physics of fingerprinting has been embraced in studies of past sea-level change, it has been largely ignored in discussions of future projections.

The conclusion which drew media attention (the Globe and Mail) and a bold-ed and italicized post from Joe Romm is that sea-level rise from melting of WAIS will be higher along will the coastlines of North America, including cities like Washington, DC, New York, and Vancouver.

The media coverage is not wrong, but misses the point. The paper demonstrates how melting of an ice sheet leads to uneven sea level rise, using WAIS as an example. In reality, if all of WAIS were to melt, so presumably would some or all of the Greenland Ice Sheet, the East Antarctica Ice Sheet and the mountain glaciers. The melting of all that other ice would also influence the geography of sea level rise. The take home message of the paper is not we need to start sandbagging along English Bay beaches here in Vancouver. The message is that the scientific community – and I assume by extension the environmental community – needs to remember that the oceans’ rise will not be level. The concluding sentences of the paper:

Any robust assessment of the sea-level hazard associated with the loss of major ice reservoirs must, of course, account for other potential sources of meltwater, namely Greenland, the East Antarctic, and mountain glaciers. Nevertheless, future projections should avoid simple, eustatic estimates and be based on a suitably complete sea-level theory.

Amen to that.

[You can give thanks for this post to my father, who notified me of the Mitrovica et al. press coverage, and who many of you know through the macro-economic advice he periodically delivers in the Toronto Star, The Globe and Mail and on the CBC. Forget my deranged comments on economics – he is the one they really should be calling to fix the federal budget.]


Friday, February 06, 2009

Cuts to research funding

From occasional commenter crf:

"could you comment on the way the Genome Canada story is taking hold in the press, about Genome Canada, as reported in the Globe, being "The only agency that regularly finances large-scale science in Canada" (Carolyn Abraham, Globe and Mail Jan 29, 2009)"

I wish I could explain this bizarre episode. The government cuts all funding to Genome Canada, the agency which helped make Canada a leader in genetics research, and exactly the type of organization capable of creating the "shovel-ready" projects that everyone says are required to stimulate the economy [the US Senate just made a similar dubious decision, cutting funding for NSF, NOAA, etc. from the stimulus package].

The Canadian media did a nice job of picking up on the story. But the editors and reporters repeatedly make what should be an obviously wrong statement that Genome Canada was "the only agency that regularly finances large-scale science". Er, NSERC anyone?

Let me be clear: the mistake is not the important issue here -- the important issue is the government decision. It is a sad sign of how "truthiness" is infecting reporting in the internet age. Say something enough times and it becomes true in people's minds. Maybe that works? You could argue that a similar dynamic explains why the same thoroughly debunked arguments against the science of climate change (it's the sun! co2 lags temperature! the hockey stick is broken! mars is warming too!) keep re-appearing.


Thursday, February 05, 2009

Auditor General questions Canada's climate policy

Say what you will about the Canadian system of government, but it excels at producing investigations, inquiries and audits. For example, Canada's auditor general regularly issues reports on whether government policies are achieving the proposed results.

The following are excerpts from a report just released by Canada's Commissioner of the Environment and Sustainable Development, the auditor charged with evaluated federal policies to control air (pollution and greenhouse gas) emissions. They reveal a depressing lack of effort and commitment even to the weak emissions reductions policies of the current government.

1.35 In its March 2007 Budget, the federal government announced a transfer of $1.519 billion to provincial and territorial governments under the Clean Air and Climate Change Trust Fund. The Trust Fund is an element of Turning the Corner, a government initiative described by Environment Canada as "Canada's plan to reduce greenhouse gas emissions and air pollution." Both the 2007 Budget and Turning the Corner state that the Trust Fund will yield real reductions in greenhouse gas emissions and other air pollutants. No expected reductions from the Trust Fund were quantified in these documents.

1.39 Analysis supporting Environment Canada's expected greenhouse gas emission reductions is weak. There are problems in how the 80 megatonnes of expected reductions against the Trust Fund for the years 2008 to 2012 were derived. The Department conducted almost no analysis to support that figure, and did not perform key types of analysis. The little analysis it did undertake is based on flawed assumptions—for example, that all provinces and territories face identical opportunities, challenges, and economic conditions for achieving emission reductions. Since the basis for the estimate is flawed, we cannot determine what a reasonable range of expected results should have been.

1.40 Environment Canada cannot monitor or verify the Trust Fund results. In our December 2008 Auditor General's Report, Chapter 1, A Study of Federal Transfers to the Provinces and Territories, we note that the provinces and territories frequently have no legal obligation to spend sums transferred to them through a trust fund for the purpose announced by the federal government. Provinces and territories also frequently have no legal obligation to report to the federal government on how the money was spent and what was achieved. Environment Canada has acknowledged that the provincial and territorial governments are accountable only to their own constituencies for expenditures and results under the Trust Fund, not to the federal government. The Department has not developed and implemented even a voluntary system for monitoring greenhouse gas emission reductions under the Trust Fund. Nevertheless, Environment Canada made a claim of expected results in 2007 and repeated it in 2008, knowing that the nature of the Trust Fund makes it very unlikely that the Department can report real, measurable, and verifiable results.

1.59 Estimates by Environment Canada indicate that the Public Transit Tax Credit will lead to negligible reductions in Canada's greenhouse gas emissions. Equally questionable is the impact of the Clean Air and Climate Change Trust Fund, which transfers over $1.519 billion to the provinces and territories to help them lower greenhouse gas emissions. Environment Canada has estimated that the initiative will lead to emission reductions totalling 80 megatonnes from 2008 to 2012. However, it has arrived at that figure on the basis of flawed analyses. The government has stated that it does not intend to monitor whether targets are achieved because it does not have access to the necessary information and cannot control what the recipient governments do with the funding. Environment Canada made a claim of expected results in 2007 and repeated it in 2008, knowing that the nature of the Trust Fund makes it very unlikely that the Department can report real, measurable, and verifiable results.


Monday, February 02, 2009

Skepticism about corals and rising CO2

The recent spate of "skeptical" climate change reporting and posting - which I personally feel is largely weather and opportunity-based - have included some serious misinterpretations and misrepresentations of coral reef science. For example, Climate Shifts tells the story of an amusing report from the "Center for the Study of Carbon Dioxide and Climate Change".

The latest screed comes from Watts up with that goes after the threat of rising CO2:

This does indeed sound alarming, until you consider that corals became common in the oceans during the Ordovician Era - nearly 500 million years ago - when atmospheric CO2 levels were about 10X greater than they are today.

What follows is a graph of temperature and CO2 over the past several hundred million years which I'll let the geologist argue over.

Now like the author of that post, I'm not one of the world's experts on reef development. So, instead, let me defer to one. This is a quote from the beginning of Charlie Veron's Corals of the World (page 33-34), the three volume tome found on the shelf of pretty much every reef scientist out there:

By the Middle Ordovician, complex algae and invertebrate reef communities had become widespread and reef biota had diversified... Reef development reached a peak in the Devonian Period and even after all this time, what remains today of those reefs are sometimes of awesome size... Corals were seldom the dominant organisms of Devonian reefs although rugose corals are often abundant in them and have a wide variety of growth-forms. Tabulate corals, which were a less varied group, mostly occupied protected or inter-reef environments.

There were reefs during those earlier era. Read on:

Unlike the Scleractinia (ed - the order of stony corals found today), both these groups of corals made excellent fossils becauase their skeletons were made of calcite, a far more stable form of calcium carbonate that the aragonite skeltons of Scleractinia.

Yes, corals evolved over time. Today's coral species date back in the tens not the many hundreds of millions of years. The type of calcium carbonate (aragonite) today's corals secrete is more sensitive to changes in the CO2 or carbonate concentration, no doubt in part because those corals have persisted through a period in which CO2 was lower than today.

Any reef experts wish to comment?

Update: A reader reminded me of this recent article by Veron in the journal Coral Reefs. The author hypothesizes that high CO2 /acidification may have caused some of the major marine extinction events in the geological past. It also addresses the very question of whether corals could have persisted in a high CO2 world in the past:

Two possibilities present themselves: (1) Reefs may not have proliferated at all
during CO2 highs; they may just appear to have survived because they were able to resume growth when levels fell. (2) The high apparent CO2 levels of ancient times may be
an artefact of a lack of data and measuring method.

Veron also again addresses the fact that today's corals are different:

Reef proliferation in the distant past during periods when atmospheric CO2 may have been high could mean that the reef builders and consolidators were better adapted to these conditions and could exploit the enhanced calcification and photosynthesis promoted by warmer sea surface temperatures without adverse effects. Many organisms in the ancient oceans would have been more tolerant to acidification through their dependence on calcitic skeletons rather than aragonite or high-magnesium calcite. There may have been other aspects of coral biology that allowed ancient corals to tolerate water chemistries that are lethal to today’s Scleractinia. If so, it would be more than interesting to know what those physiological mechanisms were.