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Nifty Imagery
Dec. 5th, 2008 12:08 pmLow-Temperature Scanning Electron Microscopy of Snow Crystals
I particularly like the rime and graupel images, the magnification series, and the crystal classification illustrations.
I particularly like the rime and graupel images, the magnification series, and the crystal classification illustrations.
Please Answer
Nov. 17th, 2008 05:19 pmThis isn't a meme, but neither is it homework. It is related peripherally to my forthcoming Ph.D. work.
What about winter precipitation (freezing rain, sleet, snow), especially but not necessarily related to climate change, do you wish we (or even just you) knew more?
What about winter precipitation (freezing rain, sleet, snow), especially but not necessarily related to climate change, do you wish we (or even just you) knew more?
Favorite Month
Oct. 1st, 2008 08:08 amSeptember 2008 is gone. October is generally my favorite month. Not because my birthday is Sunday. Or a number of other birthdays in/close to this month (evidence that January and February are cold? ;-)). Never did much regarding Halloween growing up, so that's not been too big a deal for me, either.
It's because of weather like this morning. Cool, dry, breezy. Low hanging stratocumulus. Leaves starting to turn. Pumpkin pie. Sure, it's the beginning of the road to winter, and winters can depress me with long cold spells, but I like now.
Edit to Add: My new office mate hails from Puerto Rico. She's been awaiting the fall cool-down with a mixture of excitement and fear (more so for the coming winter). This morning she walked to campus wearing flip-flops. At 43 degrees F. Let me just say I don't think she'll be doing that again. ;-)
It's because of weather like this morning. Cool, dry, breezy. Low hanging stratocumulus. Leaves starting to turn. Pumpkin pie. Sure, it's the beginning of the road to winter, and winters can depress me with long cold spells, but I like now.
Edit to Add: My new office mate hails from Puerto Rico. She's been awaiting the fall cool-down with a mixture of excitement and fear (more so for the coming winter). This morning she walked to campus wearing flip-flops. At 43 degrees F. Let me just say I don't think she'll be doing that again. ;-)
Meteorology's Maytag Repairmen?
Sep. 29th, 2008 09:02 amEnvironment Canada: Canadian Hurricane Center
Except for the recent current Hurricane Kyle and providing general info for travelers on other ones, I suppose, it never occurred to me that Environment Canada would even have a Hurricane Center. :-)
Except for the recent current Hurricane Kyle and providing general info for travelers on other ones, I suppose, it never occurred to me that Environment Canada would even have a Hurricane Center. :-)
A Day without Math
Sep. 4th, 2008 08:46 amMy math class homework, at least. I figure I need to (a) give my brain a day off from working on it to see if that helps, and (b) I need to get some research work done this week and not obsess over the remainder of the assignment. Of course, just as I finished building the 3D app on the PC for my work for the day, I got a notice from ITaP regarding some Windows updates that have been pushed to the machine because they were "past deadline". So I'm waiting for Windows Update to finish futzing with it and then I get to start over.
The rain we're supposed to get later today, through the next couple of days, will be brought to us by the remnants of Gustav.
And yes, I have my umbrella.
The rain we're supposed to get later today, through the next couple of days, will be brought to us by the remnants of Gustav.
And yes, I have my umbrella.
At last the world is safe, eh Fallout Boy?
Sep. 3rd, 2008 08:22 pmNote to Self: Never go to the Math building without your umbrella. Unforeseen showers blew up while in class this afternoon, and I got drenched getting from Math all the way to MSEE, the only tunnel access I knew about to get to the parking garage. Ah, well. A change of clothes when I got home and all was well. Laptop may have lost a USB port from being in my backpack all that way, but I've got three other ports that work, and everything else seems fine.
Speaking of Math, I'm now halfway done with the first assignment, the one I posted here yesterday. I'd completed three problems (well, two plus half of one and half of another) before going to see the prof during his office hours this morning. Finished another half problem after that. Prof gave hints on the rest of them, but I'm still not sure I absorbed the hints. May need to see him again Friday.
This weekend is likely to be laundry, homework, more unpacking (particularly in my office, in case I need to get to some reference material for said homework), and hopefully a bike ride. Going to be cooler, so unless I eat something unsettling again, I think a ride is more likely. I'll get a chance to try out the new riding gear, too.
Speaking of Math, I'm now halfway done with the first assignment, the one I posted here yesterday. I'd completed three problems (well, two plus half of one and half of another) before going to see the prof during his office hours this morning. Finished another half problem after that. Prof gave hints on the rest of them, but I'm still not sure I absorbed the hints. May need to see him again Friday.
This weekend is likely to be laundry, homework, more unpacking (particularly in my office, in case I need to get to some reference material for said homework), and hopefully a bike ride. Going to be cooler, so unless I eat something unsettling again, I think a ride is more likely. I'll get a chance to try out the new riding gear, too.
Recent Chicago Wind Storm
Aug. 7th, 2008 08:45 pmFifth tornado confirmed for Chicago area (Orland Park).
A lot of damage in the area, however, was caused by a derecho.
A lot of damage in the area, however, was caused by a derecho.
'You better build an arky, arky.'
Mar. 19th, 2008 11:39 am'There's gonna be a floody, floody.'
Glad we don't live and I don't go to school farther south. I had enough concern about the Civic getting through the flooded end of our street this morning and almost turned around and got the Subaru.
( Indianapolis weather radar storm totals data - so far )
Some parts of the state have already gotten 7 inches.
Glad we don't live and I don't go to school farther south. I had enough concern about the Civic getting through the flooded end of our street this morning and almost turned around and got the Subaru.
( Indianapolis weather radar storm totals data - so far )
Some parts of the state have already gotten 7 inches.
Very-High-Speed Lightning Video
Mar. 10th, 2008 11:18 amIf you recall my post back in January when I was at AMS in New Orleans and got particularly excited about a presentation by a National Geographic researcher's 10,000+ frames-per-second lightning video, you can now see more in this clip. (Clip is about 6 minutes. The super-high-speed footage is close to the beginning and again (better and explained) about 5 minutes into it.)
Why Weather Forecasts Are So Difficult
Feb. 26th, 2008 08:22 amThere was some kvetching on the radio this morning about the missed forecasts we've had this month, especially with snow coming today, and it just annoyed me.
This is one of my pet peeves, and it was so even before I headed down this career path. It's also one reason (of many) I don't want to go into forecasting.
Try this at home. I dare ya:
- Take a huge not quite spherical ball.
- Cover it with a very irregular surface, about 3/4 of which is water.
- Cover that with a thin mixture of gases that gets exponentially thinner as you go up from the surface.
- Tilt it 23.5 degrees, with a bit of wobble.
- Spin it.
- Heat it irregularly via a huge ball of fusing gas about 93 million miles away.
- Send it around that ball of gas in an elliptical orbit so its distance to the heat source changes.
- Accurately tell me what all the gases covering the first ball are going to do at any given time and place in the future.
Go on.
The other problems?
1. We know the set of mathematical equations that describe how that mix of gases flows around the big ball, with and without varying amounts of water vapor. Unfortunately, that set of equations cannot be solved exactly by any known means.
So the forecasters build models that make approximations. Approximations introduce error. What a concept.
2. We don't have accurate observations in enough places or often enough. I've heard via a third party someone (on faculty here at Purdue, supposedly, but I don't know whom) theorized that if we had observations about every square kilometer and every 300 meters in altitude through the troposphere (the bottom 11 km or so), we might have enough observations to calculate the models accurately.
Forecasters make mistakes. Now you know why.
This is one of my pet peeves, and it was so even before I headed down this career path. It's also one reason (of many) I don't want to go into forecasting.
Try this at home. I dare ya:
- Take a huge not quite spherical ball.
- Cover it with a very irregular surface, about 3/4 of which is water.
- Cover that with a thin mixture of gases that gets exponentially thinner as you go up from the surface.
- Tilt it 23.5 degrees, with a bit of wobble.
- Spin it.
- Heat it irregularly via a huge ball of fusing gas about 93 million miles away.
- Send it around that ball of gas in an elliptical orbit so its distance to the heat source changes.
- Accurately tell me what all the gases covering the first ball are going to do at any given time and place in the future.
Go on.
The other problems?
1. We know the set of mathematical equations that describe how that mix of gases flows around the big ball, with and without varying amounts of water vapor. Unfortunately, that set of equations cannot be solved exactly by any known means.
So the forecasters build models that make approximations. Approximations introduce error. What a concept.
2. We don't have accurate observations in enough places or often enough. I've heard via a third party someone (on faculty here at Purdue, supposedly, but I don't know whom) theorized that if we had observations about every square kilometer and every 300 meters in altitude through the troposphere (the bottom 11 km or so), we might have enough observations to calculate the models accurately.
Forecasters make mistakes. Now you know why.
Best Snow Forecast EVAR!
Feb. 21st, 2008 07:16 pmOn the way home from school, in rather nasty conditions on I-65, I was listening to the big local news-talk station. Their drive-time weather is handled by Brian Wilkes, one of the local TV meteorologists who is actually pretty good.
The radio anchor said he had an e-mail from a listener wanting to know, "How much snow are we really going to get? Hmm? Wink-wink nudge-nudge."
Brian's answer: "All of it."
The radio anchor said he had an e-mail from a listener wanting to know, "How much snow are we really going to get? Hmm? Wink-wink nudge-nudge."
Brian's answer: "All of it."
Solar Assistance
Feb. 13th, 2008 02:39 pmThe gamble of putting off shoveling the driveway and then feeling crappy today paid off.
Thanks to my friend insolation, even though the average air temperature has been well below freezing today, the snow on the driveway is significantly thinner. Tomorrow should bring similar cloud cover and temps above 40 hopefully to take care of the rest.
Thanks to my friend insolation, even though the average air temperature has been well below freezing today, the snow on the driveway is significantly thinner. Tomorrow should bring similar cloud cover and temps above 40 hopefully to take care of the rest.
We got little over a dusting at home. About the same up here at school, less in-between.
Took the wagon just in case I hit any rough spots. It didn't take me any longer actually to drive to school, but it did take longer to get here this morning, because I stopped at two different exits on I-65 to scrape off my windshield and clean the wiper blades. The defroster on full-blast couldn't keep up with the light freezing rain. It didn't seem to be making the roads bad, but it was hell on the windshield.
"They" are still saying 1-2 more inches up here in the Lafayette area, at least, throughout today. We'll see...
Took the wagon just in case I hit any rough spots. It didn't take me any longer actually to drive to school, but it did take longer to get here this morning, because I stopped at two different exits on I-65 to scrape off my windshield and clean the wiper blades. The defroster on full-blast couldn't keep up with the light freezing rain. It didn't seem to be making the roads bad, but it was hell on the windshield.
"They" are still saying 1-2 more inches up here in the Lafayette area, at least, throughout today. We'll see...
White Death from the Sky, My Aunt Fanny
Feb. 1st, 2008 11:37 amSo we were supposed to get my a big 10 inch snowfall overnight and today.
It's flurrying, and we have maybe an inch on the ground.
Snow forecasts are such a PITA.
It's flurrying, and we have maybe an inch on the ground.
Snow forecasts are such a PITA.
Weather Radar & Snow
Jan. 31st, 2008 09:32 pmThe IND weather radar has looked like it's been snowing around where I've been most of the day. Not a flake has fallen from the sky yet that I've seen.
Why is that?
Well, there are three primary reasons (a bit simplified to get the gist):
- Ice crystals (which is, after all, what snow is made of) reflect the radar beam more effectively than water at the same particle size (ice particles reflect a stronger radar echo than the same size water droplet). Those small ice crystals may not be heavy enough yet to fall as snowflakes.
- We can see those crystals way up in the clouds because, even at the lowest angle of the radar scan, the beam gets higher in the air the farther away from the radar site (thanks to the slight upward point and more importantly, the curvature of the earth). At school, I'm about 52 miles directly from the IND radar. The lowest beam is over 4600 feet above my head there. Even here at home (20 miles away) the lowest beam is over 1300 feet up. Liquid cloud droplets that high, if they aren't big enough to be raining, aren't going to reflect enough radar signal to register.
- Some of the small snowflakes may be falling into dry air under the cloud and sublimating right back into water vapor. As far as I know, this is called "virga" just like liquid rain that evaporates before reaching the ground.
Today's lesson brought to you by the number 42 and the letter W. ;-)
Why is that?
Well, there are three primary reasons (a bit simplified to get the gist):
- Ice crystals (which is, after all, what snow is made of) reflect the radar beam more effectively than water at the same particle size (ice particles reflect a stronger radar echo than the same size water droplet). Those small ice crystals may not be heavy enough yet to fall as snowflakes.
- We can see those crystals way up in the clouds because, even at the lowest angle of the radar scan, the beam gets higher in the air the farther away from the radar site (thanks to the slight upward point and more importantly, the curvature of the earth). At school, I'm about 52 miles directly from the IND radar. The lowest beam is over 4600 feet above my head there. Even here at home (20 miles away) the lowest beam is over 1300 feet up. Liquid cloud droplets that high, if they aren't big enough to be raining, aren't going to reflect enough radar signal to register.
- Some of the small snowflakes may be falling into dry air under the cloud and sublimating right back into water vapor. As far as I know, this is called "virga" just like liquid rain that evaporates before reaching the ground.
Today's lesson brought to you by the number 42 and the letter W. ;-)
*peeks out*
Jan. 30th, 2008 06:05 amApparently we lucked out. There's a dusting of flurries and a bit of ice on the verges here, but the roads I need to use to get to school are merely wet as reported by the state police. So much for the accumulation of snow and the tornadoes. Some folks in central Indiana did have wind damage: 80 mph gusts.
It is cold, though. 8. Wind chill -20. Time to make sure the Civic starts (thank $Deity for the garage) and head to school.
(Speaking of the Civic, poor thing turned over 50,000 yesterday right before I got home. It's not even two years old until May.)
It is cold, though. 8. Wind chill -20. Time to make sure the Civic starts (thank $Deity for the garage) and head to school.
(Speaking of the Civic, poor thing turned over 50,000 yesterday right before I got home. It's not even two years old until May.)
( Dooooomed! (IND Weather Radar Image) )
Aaaand... they've just issued the first local Tornado Warning a bit to our southwest. To think by morning we're supposed to have ~ 2 inches of snow and wind chills below 0.
Aaaand... they've just issued the first local Tornado Warning a bit to our southwest. To think by morning we're supposed to have ~ 2 inches of snow and wind chills below 0.
