For those of you attending "Dr." Mortenson's talk in Morris, MN today - a popular claim is that the canyon carved by the Toutle River after Mt St Helens is 40 times smaller than the Grand Canyon. The Toutle River canyon, being eroded out in a relatively short period of time, provides a seemingly perfect analogy for the 40 (or even 100) days of the "Flood."
But this is wrong on many, many levels. The simplest is one of geometry. The Toutle River canyon is almost one fortieth the length of the grand canyon (close enough to use that number for now). But, it is also nearly one fortieth as wide, and more than one fortieth as deep. Since we should consider dimensions of volume if talking about size, we are looking at a comparison of something less than 1/(40*40*40)th the size of the grand canyon. So the Grand Canyon is actually 64,000 times larger. That's 175 years worth of material flux. All of this is predicated on the assumption that erosion of the Toutle River canyon is equal to erosion of the Grand Canyon. This assumption is stupid and false. Only a fool would assume the two systems are equally comparable. But that hasn't stopped people I guess...
If you aren't moving at a snail's pace, you aren't moving at all. -Iris Murdoch
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Sunday, February 27, 2011
How old is the earth?
Very old. About 4.54 Billion years old. Plus or minus one percent. That's about 40 million years of uncertainty - not much if you consider the immensity of even just a billion years.
Greg Laden provides a great summary of how we have arrived at such a large number.
Greg Laden provides a great summary of how we have arrived at such a large number.
Convergence!
I'm headed to CONvergence in the Twin Cities (of MN) this summer. I'll be on a few panels - and I'll put together some corresponding blog posts as well. One of the panels is going to be very interesting - I'm sitting with PZ Meyers and Greg Laden to talk about evolution. I assume there will be others on the panel, but I don't know who will be there yet.
The theme for the CON this year is "steampunk." At least, more steampunky than previous years. So PZ, Greg and I were tweeting about what to wear. Goggles and Top Hats seem to be the consensus. Although I'm leaning towards Pith Helmet and Monocle.
The theme for the CON this year is "steampunk." At least, more steampunky than previous years. So PZ, Greg and I were tweeting about what to wear. Goggles and Top Hats seem to be the consensus. Although I'm leaning towards Pith Helmet and Monocle.
Friday, February 25, 2011
Private Pay Parity?
Let me be clear. As an assistant professor, I earn about $20,000 less than the "average" salary for people in the UW-System. Please don't make me teach you the difference between "median" and "mean." Just remember that high-level administrators contribute to that average. I could be making almost twice as much money as I am now if I had gone into a private-sector, industry job. But I didn't - because education, and access to it for all, is very important.
You primitive screwheads in the legislature don't seem to understand this. You keep yammering about some mythical cushy public sector job. I have yet to see one. You're eating our seed corn. Thanks a lot.
You primitive screwheads in the legislature don't seem to understand this. You keep yammering about some mythical cushy public sector job. I have yet to see one. You're eating our seed corn. Thanks a lot.
Thursday, February 24, 2011
Thurs-Demo: The one with the mud.
Here's a quick video that demonstrates the effect of clay flocculation.
Update now with embedded video goodness!
Update now with embedded video goodness!
Clay Flocculation from Matt Kuchta on Vimeo.
Wednesday, February 23, 2011
Specific Gravity
A few days ago, I posted a graph. I poured a measured mass of sand into a beaker that was designed to allow any displaced water to flow into another container. I then compared the displaced water to the mass of the sand I added. This gave me a quick way to measure how much heavier than water was the sand. This value is termed "Specific Gravity." It's dimensionless and allows us to understand how much a given amount of something will weigh (or mass, if you aren't factoring in gravity). It compares the mass of an object to an equal amount of water - it's comparable to density.
Instead of taking a few measurements and then averaging all the results, I graphed the mass of displaced water versus the mass of sand. The "trend line" represents a linear best-fit of the data. It's a way to calculate a variable that minimizes the inherent uncertainties with individual measurements. From the line, it appears that the sand is a little more than 2.7 times as dense as water (SG=2.7).
Steve Gough of Riparian Rap (Little River Research & Design) mentioned that their group was trying to figure out a way to measure mass flux in their river models. This got me thinking about how sedimentologists use the specific gravity of a fluid with suspended silt and clay as a method of figuring out how many particles of a given size are in a sediment sample (I talked about Stoke's Law previously here). Over time, the larger particles will fall faster - so the change in specific gravity of the fluid will start at some value and then gradually decrease as the large particles fall to the bottom.
This should work for the material coming out the drain on the river models, too. Although the particles are settling out of suspension much faster, the plastic grains will still cause a small change in the specific gravity as they push the water out of their way on their descent to the bottom. So I ran a trial - sure enough, the sand falling through the column of water created a small increase in specific gravity (about 4%). I also had issues with the sand interfering with the hydrometer as it fell. But, with a little work, one could probably translate change in SG to an amount of sediment moving through the column.
Incidentally, this is one reason why it's nearly impossible to get completely "sucked under" by quicksand. The suspended sand particles in water actually become more dense than regular water. Since the human body is about the same density as water, you are even more buoyant. Although you could still get stuck and starve to death...
I'm uploading a video - I'll add it to this page when it's ready. It's still loading, but if I don't get to the editing, you can preview it on Vimeo here.
Updated to embed video:
Funny: another recent post about SG here: http://jonathanmcgehee.wordpress.com/
Instead of taking a few measurements and then averaging all the results, I graphed the mass of displaced water versus the mass of sand. The "trend line" represents a linear best-fit of the data. It's a way to calculate a variable that minimizes the inherent uncertainties with individual measurements. From the line, it appears that the sand is a little more than 2.7 times as dense as water (SG=2.7).
Steve Gough of Riparian Rap (Little River Research & Design) mentioned that their group was trying to figure out a way to measure mass flux in their river models. This got me thinking about how sedimentologists use the specific gravity of a fluid with suspended silt and clay as a method of figuring out how many particles of a given size are in a sediment sample (I talked about Stoke's Law previously here). Over time, the larger particles will fall faster - so the change in specific gravity of the fluid will start at some value and then gradually decrease as the large particles fall to the bottom.
This should work for the material coming out the drain on the river models, too. Although the particles are settling out of suspension much faster, the plastic grains will still cause a small change in the specific gravity as they push the water out of their way on their descent to the bottom. So I ran a trial - sure enough, the sand falling through the column of water created a small increase in specific gravity (about 4%). I also had issues with the sand interfering with the hydrometer as it fell. But, with a little work, one could probably translate change in SG to an amount of sediment moving through the column.
Incidentally, this is one reason why it's nearly impossible to get completely "sucked under" by quicksand. The suspended sand particles in water actually become more dense than regular water. Since the human body is about the same density as water, you are even more buoyant. Although you could still get stuck and starve to death...
I'm uploading a video - I'll add it to this page when it's ready. It's still loading, but if I don't get to the editing, you can preview it on Vimeo here.
Updated to embed video:
Hydrometer Test from Matt Kuchta on Vimeo.
Funny: another recent post about SG here: http://jonathanmcgehee.wordpress.com/
Tuesday, February 22, 2011
Pro-Tip:
Here's a helpful bit of info - double check the temp setting on the drying oven before putting plastic into it.
Yeah, so I was drying some sand (which was in a glass beaker), then I wanted to finish drying some lake sediment samples my students had collected a few weeks ago. But I neglected to turn down the oven. Looks like it got a little too hot. Hopefully the lake sediment dried out, though.
Yeah, so I was drying some sand (which was in a glass beaker), then I wanted to finish drying some lake sediment samples my students had collected a few weeks ago. But I neglected to turn down the oven. Looks like it got a little too hot. Hopefully the lake sediment dried out, though.
Sunday, February 20, 2011
Sand...
Saturday, February 19, 2011
Regression to the Mean
My wife and I bought a Wii this past christmas. We only have the few games it came with, and the Wii Fit. For those of you unfamiliar with it, it's a set of games and exercise routines - most of which take place on a balance board, which measures your center of balance, weight, etc. It also includes a "Wii Fit Age," which, by some calculus of body mass index combined with your reaction time, accuracy, stability, etc. indicates your overall body/mind age.
Doing well on the tests (by keeping still and balanced on one foot, or moving the little ball with your center of balance to a specific point, or whatever) results in a lower age score. I have no idea how these things are calculated - although you can generally figure out how to do well on each of the tests through feedback during the test and iteratively over the course of several tests. It's important to realize that these tests are not found anywhere else in the Wii Fit programs. The only time you see them is by calculating your Wii Age. So you can't go and practice all the tests outside of class.
The graph below shows the results for my "Wii Age" over the past two months. The vertical axis represents the difference between the calculated age and my real age. The horizontal axis represents each test from the first to the most recent (roughly comparable to time).
There are a few things you can see in the above data. First, The result of any one test is quite different from another - especially at the beginning. The variability in the results is less as time goes on. The other observation to make is the maximum calculated age decreases, but the minimum age doesn't change much. Also, most of the scores are a little less than my calendric age - I don't know how the programmers decided what a person of my age should do on these tests, but whatever that is, I'm doing a little better. (Go me, eh?)
This is a good, everyday example of what's referred to as "Regression to the Mean." That's to say that there's some average or mean score that represents what I will most likely get. However, each test is different for each trial so there is a chance that any particular test will have tasks that I am good at or ones that, for whatever reason, I have trouble with (tests do reappear, but there appears to be some random-like possibility of any particular test showing up).
Early on, I would find that some tests were very easy and I scored very highly (low age), while other tests were very hard to figure out and I scored very low (higher age). But over time, the poor performances improved because of practice (practice also comes from doing the other games and exercises, to be sure). As a result of improving my "worst" performances, the "mean age" also improves - but with such a small sample size it's hard to say if you can estimate my "true" mean age from these results. There are several variables at work here. The difficulty of any individual test, my level of proficiency with any particular aspect of each test, and that I have been learning the skills required to "pass" each test (balance, timing, etc). I would be wrong to say that any one point reflects my true abilities. A poor result does not imply I am getting worse. A really good result does not imply that I am dramatically improving.
Perhaps, to create a hypothetical analogy to life, I was told that by eating saltine crackers right before the test, I could boost my performance. After a bad test, I may want to eat crackers before the next one. And upon doing better, I would feel that the crackers helped. After a good score, I wouldn't have need for crackers - but doing poorly again might convince me to eat crackers again before the next test. And so on. Replace "Wii Fit" with illness ( your choice) and "crackers" with remedy (again, your choice) and you can begin to see the difficulty with ascertaining the efficacy of a medical treatment. Sick people have good times and bad. If they only take a remedy when feeling bad, they might start believing that the treatment works. When in actuality, the change in results from regression towards the mean might be the only actual effect at work.
Apply this to sports. A terrific rookie season will be hard to follow-up. The game changes, the rules change, and the player may not have as strong a sophomore year (a "Sophomore Slump" as it were). This is probably the reason behind the so-called "Sports Illustrated Jinx." An athlete usually gets on the cover as a result of an outstanding performance. They get on the cover, but there is little room for improvement - regression to the mean ability is likely.
Politics, too. Any political "mandate" cited by an elected official may be completely wrong. These mandates may be nothing more than swings from one side of the political spectrum to the other. There is no mandate - just people wanting something different from what was. WIth a two-party, either or system it's not hard to get that result. The true political zeitgeist may lie somewhere center of the politician. The politician may, after facing opposition, cite some "silent majority" that supports the extreme positions and created said mandate. But this is just imagineering.
Doing well on the tests (by keeping still and balanced on one foot, or moving the little ball with your center of balance to a specific point, or whatever) results in a lower age score. I have no idea how these things are calculated - although you can generally figure out how to do well on each of the tests through feedback during the test and iteratively over the course of several tests. It's important to realize that these tests are not found anywhere else in the Wii Fit programs. The only time you see them is by calculating your Wii Age. So you can't go and practice all the tests outside of class.
The graph below shows the results for my "Wii Age" over the past two months. The vertical axis represents the difference between the calculated age and my real age. The horizontal axis represents each test from the first to the most recent (roughly comparable to time).
There are a few things you can see in the above data. First, The result of any one test is quite different from another - especially at the beginning. The variability in the results is less as time goes on. The other observation to make is the maximum calculated age decreases, but the minimum age doesn't change much. Also, most of the scores are a little less than my calendric age - I don't know how the programmers decided what a person of my age should do on these tests, but whatever that is, I'm doing a little better. (Go me, eh?)
This is a good, everyday example of what's referred to as "Regression to the Mean." That's to say that there's some average or mean score that represents what I will most likely get. However, each test is different for each trial so there is a chance that any particular test will have tasks that I am good at or ones that, for whatever reason, I have trouble with (tests do reappear, but there appears to be some random-like possibility of any particular test showing up).
Early on, I would find that some tests were very easy and I scored very highly (low age), while other tests were very hard to figure out and I scored very low (higher age). But over time, the poor performances improved because of practice (practice also comes from doing the other games and exercises, to be sure). As a result of improving my "worst" performances, the "mean age" also improves - but with such a small sample size it's hard to say if you can estimate my "true" mean age from these results. There are several variables at work here. The difficulty of any individual test, my level of proficiency with any particular aspect of each test, and that I have been learning the skills required to "pass" each test (balance, timing, etc). I would be wrong to say that any one point reflects my true abilities. A poor result does not imply I am getting worse. A really good result does not imply that I am dramatically improving.
Perhaps, to create a hypothetical analogy to life, I was told that by eating saltine crackers right before the test, I could boost my performance. After a bad test, I may want to eat crackers before the next one. And upon doing better, I would feel that the crackers helped. After a good score, I wouldn't have need for crackers - but doing poorly again might convince me to eat crackers again before the next test. And so on. Replace "Wii Fit" with illness ( your choice) and "crackers" with remedy (again, your choice) and you can begin to see the difficulty with ascertaining the efficacy of a medical treatment. Sick people have good times and bad. If they only take a remedy when feeling bad, they might start believing that the treatment works. When in actuality, the change in results from regression towards the mean might be the only actual effect at work.
Apply this to sports. A terrific rookie season will be hard to follow-up. The game changes, the rules change, and the player may not have as strong a sophomore year (a "Sophomore Slump" as it were). This is probably the reason behind the so-called "Sports Illustrated Jinx." An athlete usually gets on the cover as a result of an outstanding performance. They get on the cover, but there is little room for improvement - regression to the mean ability is likely.
Politics, too. Any political "mandate" cited by an elected official may be completely wrong. These mandates may be nothing more than swings from one side of the political spectrum to the other. There is no mandate - just people wanting something different from what was. WIth a two-party, either or system it's not hard to get that result. The true political zeitgeist may lie somewhere center of the politician. The politician may, after facing opposition, cite some "silent majority" that supports the extreme positions and created said mandate. But this is just imagineering.
Friday, February 18, 2011
Things that Astound Me (AW #31)
So the Accretionary Wedge (vol. XXXI) is asking for surprising geological notions. Glad he clarified, because I'm learning all sorts of things about my state's government and my fellow state employees this week (some good, some sad, some stultifying).
So, in that spirit, I'm going to focus on something very, very large. And something very, very small.
Let's start with the large. In this case, it's the solar system. As a child growing up, I had all sorts of astronomy and space rocket books. The Challenger disaster still sticks in my mind as the moment where I really learned about the "costs" of space exploration. Although I didn't go on to become an astronaut (I did toy with the idea for a while, though), I still study aspects of one tiny yet important blob of silicon and metal oxide hurtling around the sun.
As an exercise in perspective, I have my students map out a scale model of the solar system on our University's campus. It's about 1,000 meters from the southernmost goalpost on our (American) football field straight north along the sidewalk to the pillar next to the Clocktower (which, amusingly, has four different times displayed on each of its faces - I don't think funds to repair it will be in the budget for a while). That gives us the bounds for our model. We'll put the sun on the north end.
At the other end, we'll place Neptune. I use Pluto's reclassification as one of those "teachable moments" that explains why scientists are very particular about words. "Planet" means something specific. If we don't call other trans-neptunian objects "planets" because they lack certain qualifications, we can't simply give Pluto a special name because we like it - if it's not a planet, then it's not a planet. Words have specific meanings - and we must try as hard as we can to say what we mean (we may or may not mean what we say, but that's an issue for the Cheshire Cat and his peers).
So, we have our solar system boundaries. Sun to Neptune = 1,000 m. We could simply divide the distance between the two and then convert all the other planetary distances the same way. Or, we could use the Astronomical Unit (AU), which is the average distance between the sun and earth (about 150,000,000 km ~93,000,000 miles). This reduces really HUGE numbers into more manageable chunks (easy to do w/o a calculator). The distance from the Sun to Neptune is about 30 AU. So, 100 m/30 AU leaves us with about 33 meters per AU. So the Sun to Earth distance is 33.3m. We can just multiply 33.3 m to each planetary distance (in AU) and place each planet on the map.
Data table for the solar system model.
We can scale the sun and planets to this model, too. The sun ends up being a little larger than a basketball. Earth is about the size of an "airsoft" BB pellet. Jupiter is a little smaller than a ping-pong ball. Now imagine holding the basketball-sun and looking down the walkway and just seeing the football field in the distance a thousand meters away. Resting on that far goal post is a marble. That marble is neptune.
Pretty cool. But it works the other way too. What if we were to take an atom of gold and scale it up so that we were holding the nucleus and the outermost electrons were on that goalpost? The nucleus would be just a little larger than a baseball. The electrons, all 79 of 'em, would be little BBs orbiting in clouds. Technically, electrons are "point" particles with no actual physical dimensions of length, width or height.
Graphical representation of object/particle sizes (distances not to scale). Click for a much larger version.
Clicking on the image will bring up an image that is about 20% larger than the model described here. That means you'll have to put Neptune about 1,200 meters away from the sun to match the size of the planet images to the distance from the sun.
And now for the mind-bending part if we tally up the mass of all the stuff in the solar system, the sun accounts for about 99.86% of the total mass in the solar system. If we tally up all the mass of the neutrons, protons (each being about the size of a marble - one inch in diameter), and electrons, the nucleus accounts for 99.98% of all this stuff. Proportionally, there's more than six times more mass outside the sun than mass outside an atomic nucleus.
There is more space in stuff than there is stuff in space*!
*For carefully measured amounts of "space." Every atom in our bodies has more empty space inside of it than can be found in our solar system.
I just find that incredibly cool and a remarkable demonstration of the vastness of space, and the tinyness of atomic particles. Trippy.
So, in that spirit, I'm going to focus on something very, very large. And something very, very small.
Let's start with the large. In this case, it's the solar system. As a child growing up, I had all sorts of astronomy and space rocket books. The Challenger disaster still sticks in my mind as the moment where I really learned about the "costs" of space exploration. Although I didn't go on to become an astronaut (I did toy with the idea for a while, though), I still study aspects of one tiny yet important blob of silicon and metal oxide hurtling around the sun.
As an exercise in perspective, I have my students map out a scale model of the solar system on our University's campus. It's about 1,000 meters from the southernmost goalpost on our (American) football field straight north along the sidewalk to the pillar next to the Clocktower (which, amusingly, has four different times displayed on each of its faces - I don't think funds to repair it will be in the budget for a while). That gives us the bounds for our model. We'll put the sun on the north end.
At the other end, we'll place Neptune. I use Pluto's reclassification as one of those "teachable moments" that explains why scientists are very particular about words. "Planet" means something specific. If we don't call other trans-neptunian objects "planets" because they lack certain qualifications, we can't simply give Pluto a special name because we like it - if it's not a planet, then it's not a planet. Words have specific meanings - and we must try as hard as we can to say what we mean (we may or may not mean what we say, but that's an issue for the Cheshire Cat and his peers).
So, we have our solar system boundaries. Sun to Neptune = 1,000 m. We could simply divide the distance between the two and then convert all the other planetary distances the same way. Or, we could use the Astronomical Unit (AU), which is the average distance between the sun and earth (about 150,000,000 km ~93,000,000 miles). This reduces really HUGE numbers into more manageable chunks (easy to do w/o a calculator). The distance from the Sun to Neptune is about 30 AU. So, 100 m/30 AU leaves us with about 33 meters per AU. So the Sun to Earth distance is 33.3m. We can just multiply 33.3 m to each planetary distance (in AU) and place each planet on the map.
Data table for the solar system model.
We can scale the sun and planets to this model, too. The sun ends up being a little larger than a basketball. Earth is about the size of an "airsoft" BB pellet. Jupiter is a little smaller than a ping-pong ball. Now imagine holding the basketball-sun and looking down the walkway and just seeing the football field in the distance a thousand meters away. Resting on that far goal post is a marble. That marble is neptune.
Pretty cool. But it works the other way too. What if we were to take an atom of gold and scale it up so that we were holding the nucleus and the outermost electrons were on that goalpost? The nucleus would be just a little larger than a baseball. The electrons, all 79 of 'em, would be little BBs orbiting in clouds. Technically, electrons are "point" particles with no actual physical dimensions of length, width or height.
Graphical representation of object/particle sizes (distances not to scale). Click for a much larger version.
Clicking on the image will bring up an image that is about 20% larger than the model described here. That means you'll have to put Neptune about 1,200 meters away from the sun to match the size of the planet images to the distance from the sun.
And now for the mind-bending part if we tally up the mass of all the stuff in the solar system, the sun accounts for about 99.86% of the total mass in the solar system. If we tally up all the mass of the neutrons, protons (each being about the size of a marble - one inch in diameter), and electrons, the nucleus accounts for 99.98% of all this stuff. Proportionally, there's more than six times more mass outside the sun than mass outside an atomic nucleus.
There is more space in stuff than there is stuff in space*!
*For carefully measured amounts of "space." Every atom in our bodies has more empty space inside of it than can be found in our solar system.
I just find that incredibly cool and a remarkable demonstration of the vastness of space, and the tinyness of atomic particles. Trippy.
Thursday, February 17, 2011
On Wisconsin?
So things in the Badger State are getting pretty crazy. I'll just provide a few facts and clearly label my opinions so that you know I am not trying to persuade my readers (I do have three followers so I can justifiably use plural pronouns here). Plus, I'm not using my "work time" so my students will still have their labs graded for tomorrow.
Fact: Wisconsin's budget is not simple, nor is it suffering from a surfeit of positive income.
Fact: The Budget Proposal from the Governor removes most opportunities for State workers to bargain as a collective (Full 12+ pp Bill here. ca. 48 pp. Summary here).
Fact: Many people disagree with each other about the above budget.
Fact: Students, teachers, and thousands of other people have taken time to voice opposition to the Governor's budget proposal.
Fact: Some of the deficit numbers cited do not conform to any sense of an "actual" deficit.
Opinion: Reward or not, any feeling of crisis - real or imagined - is a great way to motivate people.
Fact: The Governor has called his budget a "Modest Proposal."
Fact: Almost 300 years ago, Jonathan Swift also made a "Modest Proposal."
Fact: Under the budget proposal, wage increases to state employees can not be larger than the Consumer Price Index. Fun bonus fact: there is more than one way to calculate a consumer price index; some indices are much less than others.
Fact: Under the budget proposal, state employees will pay more for health care. Extra bonus fact: The cost of health care has been increasing faster than the CPI. (How much faster depends on how you figure the CPI and how you define "care.")
Opinion: This would lock state employees into salaries that is guaranteed to decrease every year. Wait, would that be "Fact?"
Opinion: I find it difficult to imagine how this enables a University to recruit the best candidates (or any school, for that matter).
Fact: I work more than 50 hours per week during the school year (9-months).
Fact: I do not draw a salary during the summer.
Fact: This summer, I will be paid for about four weeks of work through grant proposals (for 40 hrs/wk). Bonus Fact: I usually work on research projects for 8-10 weeks over the summer. Double Bonus Fact: I will often work more than 8 hrs/day over the summer. Triple-scoop Yummy Fact: One of my grant funding sources is on the chopping block at the federal level, leaving me with half of the summer salary I assumed I would have.
Opinion: Like all of my other colleagues involved in education at all levels, I work hard. And like them, I fully acknowledge the fiscal difficulties and am prepared to do my part. But any proposal that would lock me permanently into a diminishing paycheck yet ask more of my time in return doesn't make sense to me.
Fact: I am not alone. Seeing this firsthand made me feel good about being an educator for the first time in several weeks.
For those of you in Wisconsin - pay attention and participate as you will. For those of you outside the state - pay attention because we're just riding the bow wave. The ship won't come in for some time yet. And there's all sorts of exciting stuff for Universities to consider - our flagship campus may be cut away from the herd.
Fact: Wisconsin's budget is not simple, nor is it suffering from a surfeit of positive income.
Fact: The Budget Proposal from the Governor removes most opportunities for State workers to bargain as a collective (Full 12+ pp Bill here. ca. 48 pp. Summary here).
Fact: Many people disagree with each other about the above budget.
Fact: Students, teachers, and thousands of other people have taken time to voice opposition to the Governor's budget proposal.
Fact: Some of the deficit numbers cited do not conform to any sense of an "actual" deficit.
Opinion: Reward or not, any feeling of crisis - real or imagined - is a great way to motivate people.
Fact: The Governor has called his budget a "Modest Proposal."
Fact: Almost 300 years ago, Jonathan Swift also made a "Modest Proposal."
Fact: Under the budget proposal, wage increases to state employees can not be larger than the Consumer Price Index. Fun bonus fact: there is more than one way to calculate a consumer price index; some indices are much less than others.
Fact: Under the budget proposal, state employees will pay more for health care. Extra bonus fact: The cost of health care has been increasing faster than the CPI. (How much faster depends on how you figure the CPI and how you define "care.")
Opinion: This would lock state employees into salaries that is guaranteed to decrease every year. Wait, would that be "Fact?"
Opinion: I find it difficult to imagine how this enables a University to recruit the best candidates (or any school, for that matter).
Fact: I work more than 50 hours per week during the school year (9-months).
Fact: I do not draw a salary during the summer.
Fact: This summer, I will be paid for about four weeks of work through grant proposals (for 40 hrs/wk). Bonus Fact: I usually work on research projects for 8-10 weeks over the summer. Double Bonus Fact: I will often work more than 8 hrs/day over the summer. Triple-scoop Yummy Fact: One of my grant funding sources is on the chopping block at the federal level, leaving me with half of the summer salary I assumed I would have.
Opinion: Like all of my other colleagues involved in education at all levels, I work hard. And like them, I fully acknowledge the fiscal difficulties and am prepared to do my part. But any proposal that would lock me permanently into a diminishing paycheck yet ask more of my time in return doesn't make sense to me.
Fact: I am not alone. Seeing this firsthand made me feel good about being an educator for the first time in several weeks.
For those of you in Wisconsin - pay attention and participate as you will. For those of you outside the state - pay attention because we're just riding the bow wave. The ship won't come in for some time yet. And there's all sorts of exciting stuff for Universities to consider - our flagship campus may be cut away from the herd.
Thurs-Demo: The one with...?
So this weeks science demonstration? I'm not sure. Wisconsin is kind of an interesting place this week.
Meanwhile, here's a picture of some ooids!
Oh, and the latest "I and the Bird" blog carnival is up over at Greg Laden's place!
Meanwhile, here's a picture of some ooids!
Oh, and the latest "I and the Bird" blog carnival is up over at Greg Laden's place!
Monday, February 14, 2011
Happy Valentine's Day
Happy Valentine's Day!
Here's some snail pr0n for your enjoyment:
Here's some snail pr0n for your enjoyment:
Snail Love from Matt Kuchta on Vimeo.
Thursday, February 10, 2011
It came from the Lake
Another item I worked on today was to collect a sediment core from the "lake" near campus. Created in the late 1800's as a holding pond for logs, today it's often choked with cyanobacteria (blue-green algae) in the late summer. This renders the lake a smelly, green mess.
The "device" was a 1.5 m length of plastic tube, attached to about 12 ft. of iron pipe that we used to push the plastic tube into the muck below the ice. The tennis-ball piston visible inside one of the tubes is connected to a cable that holds these tennis balls just above the sediment/water interface. As the core is pushed into the sediment, the piston creates a vacuum and holds the muck inside the tube.
Our first job was to find a good spot. We used a soil auger to check the bottom material. Our first spot was too shallow, and there wasn't much sediment at all. Just a few inches of grey-green clay (often called "gley").
Of course, no field expedition is perfect - I hadn't done a good job securing an ice auger, so I showed up to the lake empty-handed for getting through the ice. Fortunately, one of my students had an ice chisel in his truck (go wisconsin ice-fishing!) and we found a nice spot - about 8' of water and a little over a foot of muck.
Pushing the corer into the sediment.
The homebuilt rig was a little wobbly, so we didn't push too hard - as we started pulling the core out, my heart kind of sank: the water inside the tube was very clear. Too clear, I thought, to have pulled up any sediment. Fortunately, though, we managed to capture the sediment-water interface intact. The water was clear inside the tube because it wasn't disturbed. Yay!
There's the bottom of the lake, now above the lake. WIth the temperature dropping rapidly, I figured we weren't going to improve on our efforts, so we took the cores back home.
The first core, on the right, was tipped over after being pulled out - so the top part was mixed and folded over a little bit. The second core shows about 30 cm of lovely, dead cyanobacteria and poorly decomposed organic material. Below this is a 3 cm-thick layer of peat and then about 7 cm of sand and gravel and scattered organic material.
This is exciting to me because we managed to sample part of what is probably the old floodplain (more specifically one of the flooded intermediate terrace surfaces). If we can get into a deeper part of the lake, perhaps this summer (yer gonna need a longer pipe) the muck layer could provide a high-resolution record of sediment input over the course of 140 years.
I'll be posting more info as time goes on - right now, I've split the core and sectioned up one of the halves to look at variation in organic matter, mineral material and other sedimentary characteristics with my students.
The "device" was a 1.5 m length of plastic tube, attached to about 12 ft. of iron pipe that we used to push the plastic tube into the muck below the ice. The tennis-ball piston visible inside one of the tubes is connected to a cable that holds these tennis balls just above the sediment/water interface. As the core is pushed into the sediment, the piston creates a vacuum and holds the muck inside the tube.
Our first job was to find a good spot. We used a soil auger to check the bottom material. Our first spot was too shallow, and there wasn't much sediment at all. Just a few inches of grey-green clay (often called "gley").
Of course, no field expedition is perfect - I hadn't done a good job securing an ice auger, so I showed up to the lake empty-handed for getting through the ice. Fortunately, one of my students had an ice chisel in his truck (go wisconsin ice-fishing!) and we found a nice spot - about 8' of water and a little over a foot of muck.
Pushing the corer into the sediment.
The homebuilt rig was a little wobbly, so we didn't push too hard - as we started pulling the core out, my heart kind of sank: the water inside the tube was very clear. Too clear, I thought, to have pulled up any sediment. Fortunately, though, we managed to capture the sediment-water interface intact. The water was clear inside the tube because it wasn't disturbed. Yay!
There's the bottom of the lake, now above the lake. WIth the temperature dropping rapidly, I figured we weren't going to improve on our efforts, so we took the cores back home.
The first core, on the right, was tipped over after being pulled out - so the top part was mixed and folded over a little bit. The second core shows about 30 cm of lovely, dead cyanobacteria and poorly decomposed organic material. Below this is a 3 cm-thick layer of peat and then about 7 cm of sand and gravel and scattered organic material.
This is exciting to me because we managed to sample part of what is probably the old floodplain (more specifically one of the flooded intermediate terrace surfaces). If we can get into a deeper part of the lake, perhaps this summer (yer gonna need a longer pipe) the muck layer could provide a high-resolution record of sediment input over the course of 140 years.
I'll be posting more info as time goes on - right now, I've split the core and sectioned up one of the halves to look at variation in organic matter, mineral material and other sedimentary characteristics with my students.
Thurs-Demo: The one with Corn Syrup
This week's demo is all about particles falling through viscous fluid. In this case, we'll be dropping some steel ball bearings into corn syrup.
The fluid behavior in the video is mostly laminar - the size of the sphere and viscosity of the fluid don't produce any separation of the flow or turbulence. I wrote a bit about Stoke's Law in a previous post. For particles falling through water, the maximum particle size that will exhibit laminar behavior is around 0.1mm. For the steel spheres, we didn't manage to see any flow separation - but did see interference with the container's edge with really big spheres.
A graph of the resulting velocity shows a nice linear relationship between the square of the sphere's radius and its terminal velocity (except for the largest spheres, where interference with the container's edge slowed them down.
What a Drag! Falling Through Syrup from Matt Kuchta on Vimeo.
The fluid behavior in the video is mostly laminar - the size of the sphere and viscosity of the fluid don't produce any separation of the flow or turbulence. I wrote a bit about Stoke's Law in a previous post. For particles falling through water, the maximum particle size that will exhibit laminar behavior is around 0.1mm. For the steel spheres, we didn't manage to see any flow separation - but did see interference with the container's edge with really big spheres.
A graph of the resulting velocity shows a nice linear relationship between the square of the sphere's radius and its terminal velocity (except for the largest spheres, where interference with the container's edge slowed them down.
Tuesday, February 08, 2011
Well that was different...
So, it's been a kind of a weird few days. My friends Kelly McCullough (cool author), his wife Laura (cool professor colleague), my wife and I headed over to a well-known author's house. Because this author had a lamppost. In the woods. And Laura and Kelly wanted their picture taken next to it.
Did I mention Laura and Kelly were in costume? Yeah, they were.
The entire trip was quite surreal - the author's house is situated next to a creek. I found myself seeing two worlds. The first was my world. The landscape of my day job. House: located on a high terrace. A path descends into the stream valley and the lamppost was situated on a lower terrace overlooking the stream. The second world was full of goblins and fairies and the innumerable fey creatures that rattle around in our heads when the sun is low in the sky. As we walked down the path, I felt that we were leaving the gatehouse and crossing some great threshold to descend into a place much further removed. Having two great big white dogs, a witch, and a faun.
After the photo shoot, we scrambled back up to the world of terraces, stream incision and a warm kitchen where we got to chat with the owner of the lamppost. I came home, posted the images on flickr, and then pow. Thousands of people started looking at these pictures. Orders of magnitude more people than usually view my stuff. The author tweeted and then blogged about the adventures with his lamppost - I felt like I was trying to drink from some internet firehose.
I found out that his website has its 10th birthday tomorrow. I wanted to say "thank you" for the mention, the tea, and especially the lamppost. I figured that a little note would be the appropriately midwestern thing to do. He gets a lot of sand in the mail. I find this rather amusing (although his assistant certainly does not), since I often play the role of sedimentologist in real life. But I don't think he needs any real sand. So I set up my microscope and camera attachment to take a picture of "sand." Digging around, I found some garnet sand. Garnets are considered a traditional "birthstone" for websites born at this time of year.
Happy Weblogday, Mr. Neil!
Did I mention Laura and Kelly were in costume? Yeah, they were.
The entire trip was quite surreal - the author's house is situated next to a creek. I found myself seeing two worlds. The first was my world. The landscape of my day job. House: located on a high terrace. A path descends into the stream valley and the lamppost was situated on a lower terrace overlooking the stream. The second world was full of goblins and fairies and the innumerable fey creatures that rattle around in our heads when the sun is low in the sky. As we walked down the path, I felt that we were leaving the gatehouse and crossing some great threshold to descend into a place much further removed. Having two great big white dogs, a witch, and a faun.
After the photo shoot, we scrambled back up to the world of terraces, stream incision and a warm kitchen where we got to chat with the owner of the lamppost. I came home, posted the images on flickr, and then pow. Thousands of people started looking at these pictures. Orders of magnitude more people than usually view my stuff. The author tweeted and then blogged about the adventures with his lamppost - I felt like I was trying to drink from some internet firehose.
I found out that his website has its 10th birthday tomorrow. I wanted to say "thank you" for the mention, the tea, and especially the lamppost. I figured that a little note would be the appropriately midwestern thing to do. He gets a lot of sand in the mail. I find this rather amusing (although his assistant certainly does not), since I often play the role of sedimentologist in real life. But I don't think he needs any real sand. So I set up my microscope and camera attachment to take a picture of "sand." Digging around, I found some garnet sand. Garnets are considered a traditional "birthstone" for websites born at this time of year.
Happy Weblogday, Mr. Neil!
New kid on the blogs
Looks like my friend Tim has a new blog - and a change in career goals. He's a great guy and I wish him plenty of success.
Go on over to +/- Science to see for yourself!
Go on over to +/- Science to see for yourself!
Friday, February 04, 2011
Hawai'i Adventures: The Nene
Last year my wife and I went to Hawai'i. It was fun. I'm still processing all of 2,000+ pictures I took. But Greg Laden is hosting the next "I and the Bird" and I figured this would give me a chance to talk about some evolution/biogeography concepts.
One of the reasons people go to Hawai'i is to see plants and birds you don't find on the North American continent. The state bird of Hawai'i is the Nene (pronounced "Nay-Nay"). A large, distinctive bird, it spends a lot of time walking around on land. This rare bird can be found in a few locations you could visit on the Big Island, in Haleakala Nat'l Park (Maui), and Kauai. We didn't see any any Nene while on the big island, but did see a few at Haleakala and on the north shore of Kauai.
The Nene's scientific name, Branta sandvicensis refers to Hawaii's first distinction as the "Sandwich Isles" (named by Captain Cook after the 4th Earl of Sandwich).
At first glance, the Nene closely resembles the Canada Goose (Branta canadensis) in size and shape:
The first difference you notice are probably the plumage and coloration differences. Pay close attention to the legs - they're a little longer and more robust in proportion. The toes, too, are better separated: less connected by webbing compared to the Canada Goose (yes, I'm capitalizing the common names - I'm doing this in order to distinguish the birds).
Unlike the Canada Goose, the Nene is better adapted to the terrestrial ecosystems found on Hawaii. There are no large lakes - few vast wetlands well-suited for floating and paddling around. Rather, the grasslands, wide plains, and rocky shrublands of the Hawaiian islands would hinder a more squat, short-legged, web-footed creature.
There is, however, another remarkable connection. Based on mitochondrial DNA studies, the Nene is a direct descendent of the Canada Goose. While fascinating, it's not wholly inconceivable. Canada Geese are good fliers: a population of these birds diverted from some migratory course several hundred thousand years ago probably found the (considerably younger) islands a welcome refuge from the thousands of miles of open ocean. Without an easy way to return, they were essentially stranded. Over the generations, physical characteristics better suited for life in this tropical wilderness would be selected for. These characteristics were passed on to subsequent populations. The genetics (genotype) of the Nene we se now is different - but not that much different. The set of physical characteristics (phenotype) that make the Nene unique are easy to see. But so are the similarities. Clues to a shared genetic heritage. For example, their large bodies and long necks. Suited (well enough for survival at least) for eating plant material. Long necks and stout beaks to reach down and nip the tops of grasses and pluck/crush berries from the bushes. Great big bodies can carry a long digestive tract - all the better to ferment and digest all the cellulose-rich material.
Notice I'm referring to populations here, not individuals. Individuals do not evolve. But just like you are a little different from your parents, the populations of descendent birds are going to exhibit differences from their parent populations. Given the strong similarities in the genetics of the Nene and the Canada Goose, perhaps there were more than one population of Canada Geese that found their way to the young Hawaiian islands. Or, it may be that the selection for physical characteristics was more intense than for other subtler changes that would manifest in the genotype.
Of course, being a large bird on an island without predators is nice. Minimal risk of being eaten. But with the colonization of the islands, first by polynesian islanders, then by Europeans brought with it the introduction of other animals. Dogs, rats, mongoose - all of them more than capable of making a disastrous impact on the Nene. In addition, a leading cause of mortality among Nene nowadays is being hit by cars. These amiable birds walk along roadways and parking lots - many are hit by cars.
If you'll allow a brief bit of anthropomorphization: I envision a flock of bedraggled, exhausted geese flopping onto some distant, unknown shore. After finding the place warm, full of good food, and short on big predators, it's not hard to see why populations of these:
Stuck around and evolved into populations of these:
One of the reasons people go to Hawai'i is to see plants and birds you don't find on the North American continent. The state bird of Hawai'i is the Nene (pronounced "Nay-Nay"). A large, distinctive bird, it spends a lot of time walking around on land. This rare bird can be found in a few locations you could visit on the Big Island, in Haleakala Nat'l Park (Maui), and Kauai. We didn't see any any Nene while on the big island, but did see a few at Haleakala and on the north shore of Kauai.
The Nene's scientific name, Branta sandvicensis refers to Hawaii's first distinction as the "Sandwich Isles" (named by Captain Cook after the 4th Earl of Sandwich).
At first glance, the Nene closely resembles the Canada Goose (Branta canadensis) in size and shape:
The first difference you notice are probably the plumage and coloration differences. Pay close attention to the legs - they're a little longer and more robust in proportion. The toes, too, are better separated: less connected by webbing compared to the Canada Goose (yes, I'm capitalizing the common names - I'm doing this in order to distinguish the birds).
Unlike the Canada Goose, the Nene is better adapted to the terrestrial ecosystems found on Hawaii. There are no large lakes - few vast wetlands well-suited for floating and paddling around. Rather, the grasslands, wide plains, and rocky shrublands of the Hawaiian islands would hinder a more squat, short-legged, web-footed creature.
There is, however, another remarkable connection. Based on mitochondrial DNA studies, the Nene is a direct descendent of the Canada Goose. While fascinating, it's not wholly inconceivable. Canada Geese are good fliers: a population of these birds diverted from some migratory course several hundred thousand years ago probably found the (considerably younger) islands a welcome refuge from the thousands of miles of open ocean. Without an easy way to return, they were essentially stranded. Over the generations, physical characteristics better suited for life in this tropical wilderness would be selected for. These characteristics were passed on to subsequent populations. The genetics (genotype) of the Nene we se now is different - but not that much different. The set of physical characteristics (phenotype) that make the Nene unique are easy to see. But so are the similarities. Clues to a shared genetic heritage. For example, their large bodies and long necks. Suited (well enough for survival at least) for eating plant material. Long necks and stout beaks to reach down and nip the tops of grasses and pluck/crush berries from the bushes. Great big bodies can carry a long digestive tract - all the better to ferment and digest all the cellulose-rich material.
Notice I'm referring to populations here, not individuals. Individuals do not evolve. But just like you are a little different from your parents, the populations of descendent birds are going to exhibit differences from their parent populations. Given the strong similarities in the genetics of the Nene and the Canada Goose, perhaps there were more than one population of Canada Geese that found their way to the young Hawaiian islands. Or, it may be that the selection for physical characteristics was more intense than for other subtler changes that would manifest in the genotype.
Of course, being a large bird on an island without predators is nice. Minimal risk of being eaten. But with the colonization of the islands, first by polynesian islanders, then by Europeans brought with it the introduction of other animals. Dogs, rats, mongoose - all of them more than capable of making a disastrous impact on the Nene. In addition, a leading cause of mortality among Nene nowadays is being hit by cars. These amiable birds walk along roadways and parking lots - many are hit by cars.
If you'll allow a brief bit of anthropomorphization: I envision a flock of bedraggled, exhausted geese flopping onto some distant, unknown shore. After finding the place warm, full of good food, and short on big predators, it's not hard to see why populations of these:
Stuck around and evolved into populations of these:
Thursday, February 03, 2011
Thurs-demo: The one with the flasks of evaporating water
Okay, so this has always bothered the dickens out of me. People who point to heavy snowstorm events as some kind of "proof" that Earth's climate isn't getting warmer. The simple fact is: heat energy is required to put water molecules into the air (as water vapor). The warmer the water, the faster it will evaporate. The warmer the air, the more moisture it can hold. When warm, moist air from the gulf meets cold air out of northern Canada, the precipitation that falls out will be snow. More moisture available equals more snow.
This week's demo is simple, but illustrates this point - warm water evaporates more quickly than cool water. A warming earth dumps a lot of heat into the ocean. This warmer water then puts a lot of water vapor into the air. In winter, despite a warmer climate, heavy snow can fall.
Granted, 0.2g of water evaporated doesn't really look all that impressive - but the temperature difference wasn't very big either. So one could easily "upscale" the demo using wide-mouth buckets or something that will present a large surface area to the atmosphere and evaporate even more water.
I'm all for discussion and reasoned debate over the mechanics of climate and the resulting weather patterns. But arguments based on easily falsified misconceptions are just plain dumb.
This week's demo is simple, but illustrates this point - warm water evaporates more quickly than cool water. A warming earth dumps a lot of heat into the ocean. This warmer water then puts a lot of water vapor into the air. In winter, despite a warmer climate, heavy snow can fall.
Warm Water Evaporation from Matt Kuchta on Vimeo.
Granted, 0.2g of water evaporated doesn't really look all that impressive - but the temperature difference wasn't very big either. So one could easily "upscale" the demo using wide-mouth buckets or something that will present a large surface area to the atmosphere and evaporate even more water.
I'm all for discussion and reasoned debate over the mechanics of climate and the resulting weather patterns. But arguments based on easily falsified misconceptions are just plain dumb.
Wednesday, February 02, 2011
Two fails for the price of one
So, there's a big snowstorm. Apparently it's kind of a big deal. For those of us to the south and east of where I am right now, I guess.
There's an image floating around the intertubes - purportedly to be a satellite photo of the big storm bearing down on the city of big shoulders (or is that kneecaps?).
(Image from http://www.nasa.gov/images/content/513813main_GOES-FULLDISK-SNOW_full.jpg)
Several news outlets and blogs have picked it up and run with the description on the photo:
It was even picked up by wired.com Visit the wired.com link - look at the first comment. Now you have the context for the title of my post.
First: the "image" is not a true satellite photo. It is a composite, based on an image of the earth taken with another satellite, combined with the images of clouds taken by the GOES satellites. GOES satellites don't have the capacity to capture color images yet. But no one is recognizing the "composite" nature of the image. Does this distort our view of the world? Yes, I think so. Is it harmful? Well, that depends... I'll try to tackle that a little later.
Second: the first comment is priceless. It wraps up several misconceptions into one snarky little blurb. An example of the character of "discourse" in society today. I will tackle this a little more today.
There's an image floating around the intertubes - purportedly to be a satellite photo of the big storm bearing down on the city of big shoulders (or is that kneecaps?).
(Image from http://www.nasa.gov/images/content/513813main_GOES-FULLDISK-SNOW_full.jpg)
Several news outlets and blogs have picked it up and run with the description on the photo:
"This visible image was captured by the GOES-13 satellite..."
It was even picked up by wired.com Visit the wired.com link - look at the first comment. Now you have the context for the title of my post.
First: the "image" is not a true satellite photo. It is a composite, based on an image of the earth taken with another satellite, combined with the images of clouds taken by the GOES satellites. GOES satellites don't have the capacity to capture color images yet. But no one is recognizing the "composite" nature of the image. Does this distort our view of the world? Yes, I think so. Is it harmful? Well, that depends... I'll try to tackle that a little later.
Second: the first comment is priceless. It wraps up several misconceptions into one snarky little blurb. An example of the character of "discourse" in society today. I will tackle this a little more today.