days: 4 & 5

sorry about missing a blog'post! YESTERDAY: i woke up and went to class. we learned about how trees prep for winter--there are 3 stages. stage 1 (tolerated -5 to -10 celcius) is when the tree stops growing and the lipids in the cells change to become more unsaturated (which means they become more flexible at lower temperatures). stage 2 (tolerated -20 to -30 celcius) is triggered by the 1st frost. the cells become dehydrated and solute concentrations (C6H12O6, glycerol, proteins) in the cells increase. solute concentration increases are important because then the water in the cell freezes at a lower temperature (less water, lower freezing temp; more water, higher freezing temp). stage 3 (triggered at -30 to -50 celcius and tolerated down to -80 celcius) is when the tree vitrificates--the glycerols pretty much turn to glass. not all trees can do this, for obvious reasons...but, mostly because if ice penetrates like this, the cells become dehydrated and the proteins denature. fun fact: the worst day for a conifer is a sunny, calm day. why? because there is a high H2O loss--transpiration is high because there is higher radiation on the leaves as the hydrogen bonds between water molecules break. after we learned about trees, we went to the lab and began to identify twigs. the twig quiz is the 19th--60% outside/field identification; 40% inside identification. after that, i did some research on my zooplankton project! lots and lots of good papers. i'm still working on a plan, and then i'll talk to my group about my idea. then we had dinner--the guys made of spaghetti! it was delicious. i love noodles. and bread. and then for dessert some of us had ice cream with chocolate syrup and some had bananas foster. i had ice cream; the bananas foster tasted too much like rum (gross). then we played some games and another girl and i came back to our cabin around 9 pm and chillaxed. TODAY: woke up, went to class at 9. we started out with an experiment. snowflakes form with supercooled water that has been frozen. so, what we did was put distilled water in test tubes and sit outside until they got to -8 celcius'ish. when they got around that point, the water either flash froze right there in the tube or we "tickled" it (imitating a nucleation point...like a piece of dust) with a pine needle or another snowflake and it froze! ten we went inside and talked about how with lakes, once the water reaches a certain uniform temperature, the freezing is instantaneous! then we talked about how with salt water there is no salt in the ice itself, and because of that the salt content of the water underneath the ice increases. that super dense ocean water is then dumped into the atlantic via currents...and boom: super duper salty winter stuff. key point: if you're thirsty and you're in the arctic, eat ice. or, melt it in a house or something. then we learned about types of lakes, stratification and how layers are key indicators of the harshness of previous winters, the type of freezing that will occur in the future, etc. OH! the bottom of a lake is usually 4 celcius. there are also 2 types of ice: black and white. the types of ice are determined by the light transmittance. black ice has the most light transmittance because it is invisible to solar light; white ice is a linear-downward slope; white ice is white because it is frozen-saturated-snow--the snow is hit with moisture, the air bubbles freeze...KABOOM! white ice. ps: ice is a really bad insulator. snow is a really good insulator. after class today, i studied twigs some more, did some more zooplankton research, and talked to the professor about adding another research project to my repertoire because i want to learn lots and lots (looks like that one is going to be analyzing the temperature difference between the outside and inside of trees via temperature probes in the bark--ultimately, seeing which stage of "winterization" some trees are in...and whether or not they will survive to the spring with the brutal temperatures we've been having!)...and then i ate lunch (teriyaki rice, peas, pineapple, bread, milk) and we all went on a nature hike and practiced identifying trees in the field! it was soooooo pretty! i love nature. yup. tonight the guys are making: pork loin (...), mashed potatoes (i donated mine), veggies, and...apparently some sort of chocolate torte? guys are so ambitious. then they're all going to have "fun" late into the night...and i'm going to watch a movie, make banana bread, and study twig names with the other girl who isn't much into that sort of..."fun." i mailed letters today, too! i'll write more. i daresay i have time. anywho, LOVE! ps: mommy, in your next letter to me (thanks for the one yesterday, too!!) can you send me some more stamps??