Carbon survey

Tomorrow, NASA launches the OCO-2 satellite, which will make a detailed map of how much CO₂ is in the atmosphere at various points on the globe. They plan to combine that data with data from other existing satellites, atmospheric sampling, and ground sampling, with the goal of finding out where CO₂ is being produced and where it's being absorbed—in very high resolution, about 3 km² per measurement, or, smaller than a big coal-fired power plant.

The satellite will be in a polar orbit which allows it to fly over every single spot on earth every 16 days, which means it will generate a complete map of CO₂ concentrations every 16 days—less the areas that were covered in cloud when it flew over on that cycle. This repeated mapping also means that seasonal variations can be tracked, to separate a long-term trend from a seasonal fluctuation.

OCO-2 measures CO₂ by measuring how much light is absorbed by the CO₂ as sunlight travels down to the surface, reflects off the planet, and bounces back up to the satellite. So, cloud cover interferes with the measurement, and repeated mapping is one of the ways they're compensating for that.

Unnatural or Natural

Something I've been thinking about for a while, even since before I did the greenwashing article series, is: what makes a thing "natural" or "unnatural"?

Many people would say that "natural" things are things which come from nature with minimal processing. It sounds like a reasonable definition at first glance, but when I try to get specific, I start running into trouble with the definitions of the words used to define "natural". They seem to be a bit fuzzy themselves, which makes the term "natural" hard to pin down.

So my first question is, what is meant, exactly, by "from nature"?

Oily algae

Algae, as well as other biologically sourced feed stocks, has been the subject of a lot of research in oil production, for what should be obvious reasons. There are several things about using some bio-sources that concern me, however. Using food cropland to grow corn or soy intended for conversion to fuel, for one, resulting in less food production (and contributing to higher food prices).

The bio-sources that don't bother me in this way are things like manure or other waste to bio-fuel. Even wood waste and scrap paper can be turned into either oil or syngas (which can be turned into oil, among other things).

But, an interesting comment in a recent press release about oil from algae caught my eye: "byproduct stream of material containing phosphorus that can be recycled to grow more algae."

Biodegradation experiment

Quite a few months ago, I mentioned a test I thought I might run. I didn't start it at the time because it was winter and my assistants for this particular test tend to be sluggish when it's cold out. Then I forgot about it for a while.

For those who followed the link above, yes, I'm talking about that test.

Meet my lovely assistants, who will be doing the actual work of the biodegradation test! It's summer now, and they're happily eating through my kitchen scraps.

Don't look under the hard hat

One morning, my co-worker picked up a hard hat off a chair in the site office trailer. This would normally have been a perfectly normal thing but on this day, there was a tarantula hiding in the cozy, dark, and air-conditioned cool place it had found overnight.

After a bit of surprised dancing, the tarantula was left alone. They're pretty mellow and not dangerous, and besides, we had to get to work outside in the hot.

A while later when we went back into the office, the tarantula was on the ceiling. With a hard hat minus its harness, we got the tarantula into the hard hat to put it outside. After, of course, my co-worker asked for a photo of himself with the tarantula.

The tarantulas, as scary as they look, weren't the scary ones in that area. It was the sort of place where you banged your boots around a few times before putting them on in the morning to make sure nothing had taken refuge inside.

I never had anything inside my boots, but one morning I did wake up to a scorpion on my pants.

Thawing sweets

Here's a thing that I didn't even know was a thing to wonder about:

You know the sugar maple, which produces the raw material for maple syrup by dripping sap into a bucket in the spring. Well, it turns out that it's not only a case of the sugar maple's sap being particularly sweet and thus well suited for this use. The sugar maple, along with a couple of other trees, are the only ones which drip their sap out in a way that can be usefully collected, and it is also particularly sweet.

The question, or rather questions, are:

Why only a few types of tree?

Why does this only happen during spring thaw, in certain temperature conditions?

How does this happen at all?

Some mathematicians from SFU on the west coast decided to calculate this east coast phenomenon.

Natural distillation

I was out snowshoeing with a friend not long ago, and ate some snow because I was thirsty. My friend made a comment about the "distilled water" taste of snow, and I suddenly realized something that, really, I've known all along—snow effectively is distilled water.

Water distillation involves vaporizing impure water, then condensing the water vapour back to a liquid. In the case of snow, water vapour in the air freezes directly into snowflake form, making them pure—distilled—water.

Raindrops, on the other hand, while they also condense out of the water vapour in the air, absorb other vapours into the drop. There are some things that absorb more easily than others, SO₂ being one of the well known pollutant related compounds that absorbs easily into water, and which makes acid rain. It's a little harder (but not impossible) to dissolve other stuff into solids.

Inspired by: bacteria

Here's another one where nature meets engineering on a microscopic scale: tiny submarines small enough to swim through your blood vessels.

Oops, wrong link.

The submarines I'm actually talking about won't carry people, but once built they could be made to carry small doses of medicine, and directed to swim to a specific spot in your body.

The reason this merits a mention in the "nature meets engineering" category is that down at the 10\(\mu\)m scale (which is to say, 100 of these lined up end to end would only reach 1mm long) you can't just build a tiny motor and propeller and expect to have the submarine go anywhere, because at that scale, the physics of it just doesn't work. Instead, what they looked at was how creatures that are actually that small get around.

How to be repellent

The chemical I want to talk about today is a widely used and very useful chemical called N,N-diethyl-3-methylbenzamide. Most people know it by its acronym, DEET.

I was recently wondering just how DEET does its thing of making mosquitoes not bite people. (Why yes, the recent gap in my posts means I was on vacation. There may have been mosquitoes involved.) Obviously, I started by searching Google Scholar.

Calcium Catastrophe

Generally speaking, a sudden drastic change in the chemistry of your environment is catastrophic. From bacteria to humans, there is a range of chemistry we can tolerate, and outside that range we tend to die.

I mentioned one major geochemical event last year, when free atmospheric oxygen first became common. That was a pretty catastrophic change for the living creatures (bacteria) who were adapted to the pre-oxygen conditions of the early earth.

Some time after that, another major geochemical event happened. Some researchers now think that this led directly to the cambrian explosion and to more complex life on earth. Even so, it was a catastrophic change—from the point of view of the creatures who didn't survive it.

Inspired by: snakes

More fantastic robots! These ones are inspired by one of the creatures I find the most fascinating: snakes.

This little guy from Carnegie Mellon Biorobotics (still tethered to its power source and remote control) can move in all kinds of ways; as the video says, not just slithering. Quite a few of these types of movement are actually very simple repetitive motions, while others are much more complicated, with more steps in the movement.

Not a sunrise, but a galaxy rise

I just discovered the "Symphony of Science" series of music videos. Gorgeous visuals in this one, both on the screen and inspired in my head by the lyrics.

I don't really have much to say about it, except that it makes me happy when I watch it. This music video has lyrics made entirely from recordings of things said by Carl Sagan (with a verse by Stephen Hawking), with their tone digitally altered to fit the melody.

Airplane-induced snow

An airplane made that hole.

Not by just flying through it and swirling the visible cloud out of the way, that makes a different pattern which doesn't last nearly as long.

It turns out that in certain conditions, airplanes can actually induce rain or snow in a localized region of a cloud, and the precipitation is what clears the hole - the water droplets that make up the cloud fall because of the airplane.

Fake snowflakes

You know how they say no two snowflakes are alike?

It turns out that they're so sensitive to the conditions they form in, and are also fragile in a turbulent area, that the odds of two snowflakes growing in precisely the same way and having the exact same collisions breaking pieces off as they go are pretty small.

There are, however, a few main shapes of snowflakes that all snowflakes follow.

How much does a cloud weigh?

I was chatting with a friend not long ago, and he mentioned that he sometimes pictured clouds as these malevolant, multi-ton monstrosities hovering overhead, just waiting to smash down on us tiny humans. And by the way, how much does a cloud actually weigh?

Clearly, this calls for some math: I decided to calculate how much a cloud actually massed.

I started out by finding a cloud that I could measure reasonably well.

I am not a flower

I was on a job site, walking outdoors, when something small and bright moved near my shoulder. My first reflex was to swat at it; there are no lack of wasps around here. Fortunately I managed to stay my hand when I recognized it—a bright yellow butterfly, exactly the same colour as my yellow safety vest.

It landed on my vest, took off, landed, took off, and kept doing that for about a minute.

"Sorry, butterfly, I'm not a flower," I said to it, standing still next to the reactor.

It landed on me a few more times, then eventually realized I wasn't actually a jackpot of a bright yellow flower, and flew away.

My co-workers probably think I'm crazy. I've rescued a ladybug from one of the tanks in the same plant. As it was walking all over my hand the way ladybugs do, one co-worker asked me why I was talking to a bug.

"I like ladybugs," I said. "They eat the bugs that eat my garden."

We've also rescued a small frog from one of the tanks, and chased another out of its daytime hiding spot inside a short length of 1/2" PVC before using it. On moving an orange road cone, another co-worker commented that he was going to go fishing, after catching some of the explosion of crickets that burst out when the sun hit them.

Despite all that, I don't like it when wasps build nests on my equipment. They're the only ones I'll get out the killing spray for—not because I have something against wasps, only that they can't be building nests on my equipment when people need to be working in that area. They can build their nests somewhere else. Unfortunately, convincing them not to keep rebuilding in the same spot requires that killing spray. I hope after hitting two nests they're getting the idea.

Inspired by: water striders

Here's another small robot that illustrates a fundamental property of physics. Like the Waalbot I mentioned last week demonstrated van der Waals forces, this one demonstrates surface tension.

Above is a water strider. Notice the dimples in the water where each foot touches the surface of the water.

Inspired by: geckos

This bit of news isn't actually all that new, but that's the nature of science: from discovery of physical principle to practical application takes a while.

So way back in the '70s, there was finally a microscope powerful enough to see what a gecko's hairy feet looked like. Because however they managed to climb polished glass, it wasn't glue, it wasn't suction cups, and it wasn't hooks or claws. This is what they found:

Yup, those are some hairy toes.

New medicine from old

Traditional medicines can be interesting things. Some don't work at all despite being widely used, but some, like the bark and leaves of willow (Salix), work very well and have been effectively used for millennia—there are written records from 500 BC referring to its use. More recently (the 1820s) the active ingredient, salicylic acid, was produced, then in the 1890s acetylsalicylic acid, what we know as modern aspirin or ASA, was created. Aspirin no longer comes from plants as willow trees can't grow fast enough to sate the world's appetite for painkillers, but is now synthesized from phenols.

Another traditional painkiller, a milkwood (Tabernaemontana) has been under investigation for several years now. According to the studies, it contains a mixture of several things, including compounds in the class of opioids (a painkiller type which tends to have undesirable side effects and which causes addiction) and conolidine, among many others.

The conolidine and other compounds were isolated and identified in 2004, but conolidine couldn't be properly studied at that time because they only managed to get a 0.00014% yield when purifying it out of the plant. In May 2011, a team of researchers from the Scripps Research Institute announced that they had not only managed to synthesize conolidine, they had also tested it on mice and found out that it had painkiller effects as strong as morphine, but without any of morphine's adverse side effects.