Monday, November 24, 2008

Ravenous curiosity

As usual, Dale over at The Meming of Life hits the nail on the head in his recent post, this time on the parenting philosophy of promoting "ravenous curiosity". His post comes as the perfect follow-up to my kids' "frozen ocean" experiment. I have to admit too that I really enjoyed this bit of snarkiness:

It’s not that religion is inherently incurious. Religion and science are both planted in the cortical freakishness that demands answers. It’s just that religion wants the answers it wants, while science wants the answers that are in the answer key. Also known as “the actual answers."

Friday, November 21, 2008

Kid Science : Frozen Ocean

A couple of weeks ago, I was in the car with my kids - Emma, 7, and Jack, 4 - when the subject of water freezing came up. I think it was the first day of the season when we had sub-freezing temperatures and I was trying to impress upon them the importance of making sure they had their hats and gloves. During this conversation, one of them (I think it was Jack) asked if the ocean ever froze. I told them that it did on very cold places like the Arctic and Antarctica, but that around here it did not generally freeze because the salt in the water prevented it (As much as may have wanted to, I didn't go into the physics of molecular motion and ice crystal formation - I'll save that for when they're a few months older!).

A light bulb went off in Emma's head - it was an amazing thing to witness. "I know what we can do! Let's put a container of water without salt and another container of water with salt outside and see if they freeze!" I can't explain how proud I was at that moment. Notice that Emma did not just want to put a container of salt water outside and see what would happen. She wanted to put both salt water and fresh water out - she had just designed a simple controlled experiment. I was smiling all the way to work that day.

The weather warmed up for a bit after that conversation, so we had to wait until yesterday to carry out Emma's experiment. After dinner, we pulled out a couple of bowls, a measuring cup, a kitchen scale, and some table salt.

I was trying to keep everything as accurate as I could so we added 500mL of tap water to each bowl and added approximately 17.5g of salt to one of them (this gives a salinity of 3.5% or 35 ppt, the average salinity of ocean surface waters, and only slightly higher than the salinity we would expect for the ocean off of New England). I asked the kids what else we needed to do and Emma realized that we needed some way to identify each bowl. She had some trouble coming up with a good system. Jack, of course, figured it out - "Emma, we just need to write 'salt' and 'no salt' on a piece of paper and tape it to the bowls."


The kids put the bowls outside on the back deck and went off to bed. I watched the temperature outside drop through the evening: 30oF, 28oF, 25oF, 23oF, 20oF. Uh oh. I hadn't anticipated such a cold night. Salt water doesn't freeze at 32oF, but it will freeze - especially sitting there in a little bowl without currents or waves - in fact, water with a salinity of 35ppt will freeze at 28.8oF. The reason the ocean as a whole doesn't freeze even when it's sub-28.8oF outside is that it has such a huge thermal mass that the water itself doesn't often get to 28.8oF. You'll see some freezing in shallow areas with little wave activity, like along the edges of tidal marshes. I was starting to fear that our little controlled scientific experiment was going to backfire and we would wake up to two frozen bowls of water and the kids would logically conclude that the salt did nothing to prevent freezing. D'oh!

When I went to bed sometime around midnight, the temperature outside was 18.8oF. Should I bring the bowl of salt water inside and then wake up before the kids, run downstairs, and put it back outside? No. That's just too deceitful and is completely counter to the lesson I was trying to teach about scientific thinking. I'll just hope for the best - perhaps the salt water wouldn't freeze as much as the fresh water. I went to bed hoping for a watery slush.

When we brought the bowls in this morning, sure enough the salt water had froze. But thankfully, like I had hoped, it was different from the fresh water. The fresh water was frozen solid, smooth like a hockey rink. The salt water was slushy, not firm at all. The kids marvelled at the difference. They banged their knuckles on the hard fresh water ice and stuck their fingers through the salt water slush. "Wow, the salt water isn't really frozen!". They played with, touched, and tasted the ices for a few minutes then headed off to get dressed for the day. Whew. To paraphrase a cogent comic - Science. It works.


Friday, November 14, 2008

Data don't lie II

This explains a lot:

(note: both variables have been transformed so neither the output score nor the consumption score values enable the identification of particular persons included in this research)

from Grim, Thomas. 2008. A possible role of social activity to explain differences in publication output among ecologists. Oikos 117(4): 484-487.

Pirate-wear

Here be a few things to add to ye plunderin' list...

from Pirate Shellfish, a Wellfleet-based shellfish farm and catering company:
Get this great t-shirt and more from 826 Valencia:

Get this one and much more from Cafe Press:

Monday, November 10, 2008

Who buys this stuff?

Some things are just too humorous not to share.

Wednesday, November 05, 2008

How blue are we really?

I came across the site of Dr. Mark Newman, a physics professor at the University of Michigan, while searching for some state-by-state data on the election. He has some interesting maps that have been transformed to try to get a better visual picture of the geography of the election results. For example, below is a "cartogram" that has resized each state based on its population and then colored with the infamous red or blue. Dr. Newman delves even further on his site by coloring individual counties various shades on the blue-purple-red continuum. It's an interesting set of images.

A Dream Unfettered

Tuesday, November 04, 2008

Need a beard?

I've already got one, but for those facially-follicly-challenged you can now "grow" your own beard without all the itching or messy trimming while helping out some people in need. If you aren't so sure a beard is for you, you should know there are 10 Very Good Reasons to Grow a Giant Beard

Sunday, November 02, 2008

Planting a Meadow

The title is not a metaphor - I am actually planting an actual meadow. Well, attempting to plant an actual meadow. OK, attempting to plant a small meadow-like area.

Part of our backyard is a swath of land with a utilities easement on it - we own the land, but the gas company has access rights and nothing can be built there. Previous owners planted grass back there and, so I've heard, kept it mowed like a lawn. I haven't continued this practice since 1) I have no desire to spend the time and energy to mow more lawn, and 2) I like my yard to provide as many natural habitats as possible (and a mowed lawn ain't much of a natural habitat). I would love to naturalize this entire back lawn, but it is a pretty big space and would require more time/effort/money to remove the existing grass than I am willing/able to give. So this summer I decided to start small.

I chose a small (~400 ft2) area to work with, figuring I can expand things in subsequent years if this preliminary work goes well. I started this project back in June, when, after mowing the grass short, I covered the area with some nylon tarps. I kept these tarps in place from June until this weekend. By keeping the area covered during the entire growing season, keeping the sun out and the temperature up, I was hoping to kill both the existing grass and a decent percentage of the grass/weed seeds lying dormant in the soil.


I pulled the tarps up this weekend and, sure enough, all vegetation was dead:


After some raking and hoeing up of dead grass tussocks, the area was ready to be sown:


By sowing seeds now, in November, in New England, I am accomplishing a couple of things. First, the wildflower and grass seeds I sow now will already be in place in the spring, ready to germinate as soon as conditions are right - this should give them a leg up (or at least an even footing) with any weed seeds out there now and I won't have to worry about working around my schedule or the unpredictable spring weather to plant. Second, some native wildflower seeds require a period of cold dormancy before they will germinate - I could have put the seeds in the fridge for the next few months, but why bother when winter can do a better job for me?

I wanted to plant a meadow, not just a wildflower garden, so I ordered both wildflower and grass seeds. I also wanted to use as many native plants as I could. After some online research, I ended up with a native wildflower seed mix from American Meadows and a short prairie grass mix from Prairie Frontiers. I augmented these with some additional native wildflower seeds. I bought enough seed for approximately 1,000 ft2, figuring I'd use half of it this year and the other half for next year's expansion.


Following a technique I found online, I split the seed I was going to use this year into two parts and mixed each part with approximately 10 parts of clean sand, which makes sowing the light, small wildflower seeds much easier. After thoroughly mixing the seed and sand, I sowed 1 part over the entire plot moving east-west and then sowed the 2nd part going north-south, thereby minimizing bare/sparse areas. The last thing to do, which is oh so important (so I've read), was to compact the seeds into the soil to ensure good seed-soil contact. Since I don't own a grass roller, I spent a half hour or so stomping around the sown plot, making sure my footprints covered every square inch of the ground.


Now I just sit back, enjoy the rest of the fall and winter, hope the birds don't eat too many of the newly sown seeds, and keep my fingers crossed for successful germination. I'll keep everyone posted.

Wildflowers sown:
Aquilegia canadensis (Eastern Red Columbine)
Asclepias incarnata (Red Milkweed)
Asclepias tuberosa (Butterfly Weed)
Aster novae-angliae (New England Aster)
Baptisia australis (Wild/False Blue Indigo)
Chamaecrista fasciculata (Partridge Pea)
Coreopsis lanceolata (Lance Leaf Coreopsis)
Eupatorium fistulosum (Joe Pye Weed)
Eupatorium maculatum (Spotted Joe Pye Weed)
Gaillardia pulchella (Indian Blanket)
Heliopsis helianthoides (Ox-Eye Sunflower)
Liatris spicata (Blazing Star)
Lobelia cardinalis (Cardinal Flower)
Lupinus perennis (Wild Perennial Lupine)
Monarda fistulosa (Wild Bergamot)
Oenothera biennis (Evening primrose)
Penstemon digitalis (Beard Tongue)
Rudbeckia hirta (Black-eyed Susan)
Rudbeckia submentosa (Sweet Coneflower)
Rudbeckia triloba (Brown-eyed Susan)
Salvia azurea (Tall Blue Pitcher Sage)
Solidago rigida (Rigid Goldenrod)
Solidago speciosa (Showy Goldenrod)

Grasses sown:
Andropogon scoparius (Little Bluestem)
Bouteloua curtipendula (Side Oats Gramma)
Bouteloua gracillis (Blue Gramma)
Koeleria cristata (Prairie June Grass)
Sporobolus heterolepis (Prairie Dropseed)