Scientific progress in a disappearing world…

Some words from one who said it best, Aldo Leopold (from The Sand County Almanac):

There are men charged with the duty of examining the construction of the plants, animals, and soils which are the instruments of the great orchestra. These men are called professors. Each selects one instrument and spends his life taking it apart and describing its strings and sounding boards. This process of dismemberment is called research. The place for dismemberment is called a university.

A professor may pluck the strings of his own instrument, but never that of another, and if he listens for music he must never admit it to his fellows or to his students. For all are restrained by an ironbound taboo which decrees that the construction of instruments is the domain of science, while the detection of harmony is the domain of poets.

Professors serve science and science serves progress. It serves progress so well that many of the more intricate instruments are stepped upon and broken in the rush to spread progress to all backward lands. One by one the parts are thus stricken from the songs of songs. If the professor is able to classify each instrument before it is broken, he is well content.

Carnegie Atmosphere Observatory: So precise, it can see your new haircut

Hema’ehu needs to come clean with this first: I work with/for these guys, and the principal investigator paid my salary (when I used to ask for pay – he is now holding my graduate degree just out of reach to get me to finish), and I’m hoping to get back on the payroll come June. So is Hema’ehu sucking up? Heck yes. Is this thing still some of the coolest sh*t you’ll ever see? Double heck yes.

The Carnegie Airborne Observatory is a combination hyperspectral remote sensing instrument, LiDAR sensor, and geocorrectional device mounted onto an airplane. The hyperspectral scanner, AVIRIS (Airborne Visible-InfraRed Imaging Spectrometer) measures upwelling (reflected) radiation from the earth’s surface. As sunlight careens through the Earth’s atmosphere and hits the ground, it comes into contact with a huge range of materials: plant, animal, buildings, yo’ mama, etc. Every physical component, down to the very tiny elemental bonds that hold something together, either reflect, scatter, or absorb that sunlight. Because the solar spectrum is wide – we can see but a tiny portion of this spectrum with our eyes – the materials (in the parlance of remote sensing, ground cover) have distinctive and unique spectral signatures due to the difference in reflection, scattering, and absorption of light at all wavelengths along the solar spectrum. So AVIRIS measures that stuff.

This is known as a passive remote sensing instrument. It merely collects information about light attenuation at an assortment of wavelengths from sunlight bounced off the Earth. The LiDAR (Light Detection And Ranging), conversely, is an active remote sensing instrument. Similar to ship sonars (or, for that matter, killer dolphin sonars) or the po-po’s speed gun, the LiDAR shoots out a beam of energy that bounces off the ground cover and returns to the airplane lickety-split. The time it takes the beam to hit the ground and return gives the height of the ground at that spot. So LiDAR measures height.

The on-board GPS thing is cool, too, but for more nerdy, less applicable and interesting reasons. It tells the computer on board exactly where the airplane is in three-dimensional space as it flies over the Earth. Hema’ehu would be the first to agree that this does not seem so hard, as we can all see airplanes as they fly over head. Please trust that this instrument is very precise, however, and this precision makes most remote sensing scientists drool.

The combination of hyperspectral scanner and LiDAR sensor gives an extremely high-definition image of some segment of the planet. Chris Field, the director of the Carnegie Institution Department of Global Ecology, compared the CAO’s performance to that of a “CAT-scan of Earth.”

Hema’ehu is going to let that all sink in for a bit. Here are some pictures:

All pictures are courtesy the CAO website.

Exploit Wind Not Coal

Do we really need coal electricity? Two Stanford researchers seem to think not. Apparently the winds are blowing, like, all the time, and modern turbines can capture that energy and turn it into electricity.


We’d only need about 200 square kilometers, maybe off in the ocean or South Dakota where the winds blow steady and strong.

And these turbines don’t even kill (many) birds. They’ve got about a 77 meter radius, and rotate slowly so they’re easy for birds to avoid. For humans, they also make excellent golf course hazards.

These guys have another idea: tether drones flying at 4600m to the ground and collect energy from massive turbines on the glider wings. It’s… just… crazy… enough to work.

Bio-diversity and Bio-fuels

It is remarkable that the debate over alternative, green energy resources has come so far. Ten years ago, corn ethanol was hardly known outside the world of futurist farmers and the halls of academia. Now, President Bush has voiced support for ethanol in the State of the Union address, challenging the nascent biofuels industry to produce 35 billion gallons of ethanol by 2015. Energy technology is at the forefront of our national debate.

The American public should be wary, however, of snake-oil salesman and golden-tongued charmers promoting one particular energy solution. A healthy dose of cynicism is valuable when assessing any elected leaders’ claim or plan, no less so for the President’s ambitious agenda. For all the talk of energy independence and reduced reliance on Middle Eastern oil, the motivation for corn ethanol is not sustainability and national security but politics and entrenched financial interests.

The agriculture lobby is well known throughout the U.S. as an effective and powerful figure in crafting, lobbying, and supporting the national Farm Bill, the work of laws and statutes that doles out millions of tax-payer dollars to farms. The majority of tax breaks and giveaways (including paradoxical payments to owners for keeping land out of production) go to enormous, high-technology, low-labor farms. The agri-business lobby is salivating over the growth of the corn ethanol movement, as President Bush’s State of the Union address has already resulted in an increase in the price of corn from $3.70 to $4.40 per bushel (a jump of almost 20%).

In terms of energy, corn ethanol is a seemingly logical place to start, with an immensely developed infrastructure and a forceful lobby that controls national policy. And for corn, the yields are huge: in one hectare of land (ha, about 2 football fields) over 90 gigajoules of energy can be produced (a single match contains about 1 joule of energy, and there are a trillion joules in one gigajoule [GJ]).

The energy output of corn ethanol dwarfs all other biofuels. So, too, the inputs required to grow corn are astronomical – the energy expended through farm equipment, fertilizers, herbicides and pesticides, and fuels needed to produce that hectare of corn almost matches the output derived from farming. On balance, corn ethanol has a large return only with an equally large investment. As a part of our national energy budget, we may as well not grow the corn in the first place, thereby saving on farm inputs what we would be attempting to produce as outputs.

But the striking inefficiencies of corn ethanol should not discourage us from all biofuels, lest we throw the baby out with the bath-water. A recent article in the journal Science by David Tilman, Jason Hill, and Clarence Lehman shows the potential for sustainable biofuels.

There is considerable nuance associated with the science and sustainability of biofuels, and a careful look at the details paints a fascinating portrait of an emerging and promising technologic venture. At left is a figure from the Tilman et al. article. On the vertical axis we see energy units (in GJ per ha), and along the horizontal axis are 5 potential biofuels: corn ethanol, soy diesel, and generic biomass electricity, ethanol, and synfuel. Each biofuel has two columns: the energy outputs (yield) and inputs. Below the x-axis are two calculations of the graphical data, Net Energy Balance (NEB = Output – Input) and the NEB ratio (NEB ratio = Output / Input), for each biofuel.

Unsurprisingly, corn ethanol dominates the field (pun intended) for both outputs and inputs. More importantly, the NEB for non-corn or soy biofuels is roughly equal to that of corn, and the NEB ratio for corn ethanol is exceeded by every other potential biofuel source. Most importantly, the biomass electricity, ethanol, and synfuel are all sourced from a low-input (no tillage, pesticides, or herbicides) high-diversity prairie grassland, replanted on agriculturally degraded soils (that is, they can no longer support food production).

The magnitude of this conclusion cannot be overstated, as it shows how a restored, diverse grassland can provide as much and more energy per degraded hectare than the intensive, energy expensive production of corn. This study exemplifies the care we must take in analyzing proposals by elected leaders and industry – solutions that are reasonable and sustainable are abundant, and need only be considered on balance with the prevailing status quo to show their likely success.

Our energy future will depend on a whole swath of potential and known fuel resources. Corn ethanol may serve in a transition to sustainable fuels, but maintaining food production and security while providing energy will only be possible with concerted, diversified effort. A sustainable biofuels industry will propel America into the future.