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silverrose
2004-May-04, 01:31 AM
On the "What causes the seasons" page, you state that December 21st and June 21st, the Winter and Summer solstices, are the midpoints of these seasons. In fact, officially the seasons <i>begin</i> on these dates (or whatever dates the solstices fall on in a given year). See http://apod.gsfc.nasa.gov/apod/ap001221.html for a slightly oblique reference, I'm sure there are better ones but I'm not sure which government sites to check or what terms to search on.

silverrose
2004-May-04, 01:39 AM
that's what I get for posting without reading the whole site first :( Looks like more of a disagreement than an actual error, though I do believe that the government terms the official start of the seasons to be on the solstices and equinoxes. Frankly, I think they should be the midpoints of the seasons too, that's just not how it is. Or so sayeth the gov.

Kaptain K
2004-May-04, 07:38 AM
Two words - Thermal inertia!

JohnOwens
2004-May-04, 06:20 PM
Two words - Thermal inertia!
Two more proper words - Heat capacity! (or specific heat; is there technically a difference? Either way, two words.)

Added: Oh! I see. Went ahead and looked up a bit on my own. Heat capacity is for a specific object or section of matter, and allows for how much mass it contains. Specific heat is really short for specific heat capacity, and is what you multiply by the mass to find the (non-specific) heat capacity. FYI
Next question: Which one would it be more proper to blame for the seasonal lag? I'm leaning towards "heat capacity" myself.

Maksutov
2004-May-05, 12:57 AM
that's what I get for posting without reading the whole site first :( Looks like more of a disagreement than an actual error, though I do believe that the government terms the official start of the seasons to be on the solstices and equinoxes. Frankly, I think they should be the midpoints of the seasons too, that's just not how it is. Or so sayeth the gov.

Ever been in northern New England on or about February 4th? That would be your proposed "first day of Spring". Take it from me, the natives would find such an event hilarious! Even without a leftover groundhog... :wink:

Ut
2004-May-05, 02:03 AM
New England? Come a little farther north. We're lucky to be wearing shorts by the end of June half the time, and there's STILL some rare snow on the ground 'round here.

AZgazer
2004-May-05, 02:10 AM
New England? Come a little farther north. We're lucky to be wearing shorts by the end of June half the time, and there's STILL some rare snow on the ground 'round here.

That reminds me of my time at KI Sawyer AFB in the U.P. of Michigan. I remember a softball tourney getting snowed out on May 1 and we typically had snow piles in between the runways that hung around until the end of May, early June.

We always joked about 2 seasons, winter and winter's coming. Driving SOUTH to Green Bay for 3 1/2 hours was always a talked about topic when trying to impress upon loved ones exactly where you were. :wink: The surrounding area was absolutely breath taking though.

Ut
2004-May-05, 02:20 AM
Wow. You were farther north than I am...

AZgazer
2004-May-05, 02:24 AM
I never bothered to check, but it was commonly said that our position on the map was the furthest most northern base in the Lower 48. Loring Maine looked further on the map, but we were farther north...or so it was said. I think I am going to look that up.

Maksutov
2004-May-05, 02:53 AM
New England? Come a little farther north. We're lucky to be wearing shorts by the end of June half the time, and there's STILL some rare snow on the ground 'round here.

That reminds me of my time at KI Sawyer AFB in the U.P. of Michigan. I remember a softball tourney getting snowed out on May 1 and we typically had snow piles in between the runways that hung around until the end of May, early June.

We always joked about 2 seasons, winter and winter's coming. Driving SOUTH to Green Bay for 3 1/2 hours was always a talked about topic when trying to impress upon loved ones exactly where you were. :wink: The surrounding area was absolutely breath taking though.

So you're dealing with the yoopers, eh? What did ya think of that, eh?

Go through Marinette and Menominee on the way down to civilization? :wink:

AZgazer
2004-May-05, 03:11 AM
New England? Come a little farther north. We're lucky to be wearing shorts by the end of June half the time, and there's STILL some rare snow on the ground 'round here.

That reminds me of my time at KI Sawyer AFB in the U.P. of Michigan. I remember a softball tourney getting snowed out on May 1 and we typically had snow piles in between the runways that hung around until the end of May, early June.

We always joked about 2 seasons, winter and winter's coming. Driving SOUTH to Green Bay for 3 1/2 hours was always a talked about topic when trying to impress upon loved ones exactly where you were. :wink: The surrounding area was absolutely breath taking though.

So you're dealing with the yoopers, eh? What did ya think of that, eh?

Go through Marinette and Menominee on the way down to civilization? :wink:

Ya der don'tcha know. Got me sum pastees and stroh's. Uppers > Trolls!
It wasn't civilization until you hit Milwaukee! and even that was questionable. :P Actually one of my favorite "getting out of a speeding ticket" stories involved me, the supposed speed of light, my new 5.0 and a Marinette Officer on an otherwise calm Sunday morning.... #-o

AZgazer
2004-May-05, 03:36 AM
Well I guess this a good example of why you verify "facts" yourself.

Loring AFB Maine (46.57N) which was always used as a comparision is North of KI Sawyer (46.21N), however the winner of the Northern most CONUS base would go to Minot AFB N.D. weighing in @ 48.25N.

Driving South for 3 1/2 hours to Green Bay still sounds cooler though! And no I don't want to hear anything from anyone in Tule or Clear about your drive. :P

Ut
2004-May-05, 12:03 PM
Yup, more north than I am by nearly half a degree. 46.08N

So, let me think. The trees are bare, and some of them still have snow under them. It's currently 5 degrees, with a high of 11 (that's 41 and 52, respectfully, so says EC). Is this what most people think of when they think summer?

AZgazer
2004-May-06, 12:11 AM
Seems you definately fall into the 2 season window like we did there, "Winter & Winter's coming!" :D

Ut
2004-May-06, 12:36 AM
Well, we have many seasons. Let me think...

There's Winter, which lasts from mid November until early January. Then there's Hell's Frozen Over, which stretches into March. After that we get You Think The Cold's Ending But You're Wrong, followed by Snow Lingers Until Late May. Then we get Spring through June, and Beaches Are Full of Jellyfish. Then there's Beach, which most people call the last two weeks of August, followed by The Leaves are Changing Colour which is immediately followed up by the seasons of Windy and Barren Trees. Then we settle in for two months of Winter's Coming.

The ocean gives us crazy weather, you see...

daver
2004-May-06, 12:59 AM
Well, we have many seasons. Let me think...

There's Winter, which lasts from mid November until early January. Then there's Hell's Frozen Over, which stretches into March. After that we get You Think The Cold's Ending But You're Wrong, followed by Snow Lingers Until Late May. Then we get Spring through June, and Beaches Are Full of Jellyfish. Then there's Beach, which most people call the last two weeks of August, followed by The Leaves are Changing Colour which is immediately followed up by the seasons of Windy and Barren Trees. Then we settle in for two months of Winter's Coming.

The ocean gives us crazy weather, you see...

CA has only two--fire and mud. Fire came a bit early this year.

Torsten
2004-May-06, 05:18 AM
Hmmm. I thought the 2 seasons for which we are well known are Winter and Tough Sledding. Oh yeah, last year we had fire too, and locally we call this time of year "break-up".

I often have to check soil textures in forest sites as part of my work. On May 3rd I had some difficulty digging the necessary soil pits on northerly aspects here because sometimes the ground was still frozen. And then this morning there was fresh snow at the site. Sky is clear this evening, temperature -2C.

Now, to get this at least somewhat back on astronomy or say, a story of the Sun, the Earth and geometry of sunbeams, here's some trivia: Last year, as part of another project I was doing, I downloaded an excel spreadsheet with a VBA translation of the National Oceanic and Atmospheric Administration's Solar Position Calculator and solar radiation calculations. This spreadsheet calculates the direct solar radiation normal to the beam at the Earth's surface for locations, dates and times of your choice. I added some further calculations on other tabs in order to calculate the radiation that would be incident on a surface of any particular slope and aspect.

I used June 21 as the reference date for my calculations (I was interested in maximum values). For the simple case of a 30% north aspect, a flat aspect, and a 30% south aspect at 53.5 N, the values were ~650, 821, and 923 W/m2 respectively. Well, there's part of the reason for those frozen soils on May 3rd.

The original spreadsheet can be found at: http://users.vei.net/pelican/sunrise.html

PeterFab
2004-May-06, 06:25 AM
Well, we have many seasons. Let me think...

There's Winter, which lasts from mid November until early January. Then there's Hell's Frozen Over, which stretches into March. After that we get You Think The Cold's Ending But You're Wrong, followed by Snow Lingers Until Late May. Then we get Spring through June, and Beaches Are Full of Jellyfish. Then there's Beach, which most people call the last two weeks of August, followed by The Leaves are Changing Colour which is immediately followed up by the seasons of Windy and Barren Trees. Then we settle in for two months of Winter's Coming.

The ocean gives us crazy weather, you see...

As stated by a Vietnamese student of my mother's
'Denmark has two seasons, a grey winter and a green winter.'

Maksutov
2004-May-06, 07:03 AM
Actually, starting autumn in August on the UP might not be that bad an idea. I remember an early August evening up there where the chill in the air made one think of snow, which they did in fact have a few weeks later, dontcha know.

But every astronomy text and almanac (hey, don't go there!) I have defines the seasons as starting on the solstices and equinoxes. 8)

Kaptain K
2004-May-06, 11:53 AM
In central Texas, we have nine months of summer and three months of "a little too brisk for swimming"! :o

Charlie in Dayton
2004-May-07, 08:57 PM
Quote from Marquette County native away back when:

"We got ten months of winter and two months of d@mn poor skiin'..."

Charlie in Dayton
USAF, K.I. Sawyer AFB 1971-75
Honorary Yooper

Jpax2003
2004-May-08, 05:02 AM
In Chicago we have two seasons: Snow-bound traffic, and construction-bound traffic. Or is that windy and windier.

Maksutov
2004-May-08, 12:41 PM
New England? Come a little farther north. We're lucky to be wearing shorts by the end of June half the time, and there's STILL some rare snow on the ground 'round here.

That reminds me of my time at KI Sawyer AFB in the U.P. of Michigan. I remember a softball tourney getting snowed out on May 1 and we typically had snow piles in between the runways that hung around until the end of May, early June.

We always joked about 2 seasons, winter and winter's coming. Driving SOUTH to Green Bay for 3 1/2 hours was always a talked about topic when trying to impress upon loved ones exactly where you were. :wink: The surrounding area was absolutely breath taking though.

So you're dealing with the yoopers, eh? What did ya think of that, eh?

Go through Marinette and Menominee on the way down to civilization? :wink:

Ya der don'tcha know. Got me sum pastees and stroh's. Uppers > Trolls!
It wasn't civilization until you hit Milwaukee! and even that was questionable. :P Actually one of my favorite "getting out of a speeding ticket" stories involved me, the supposed speed of light, my new 5.0 and a Marinette Officer on an otherwise calm Sunday morning.... #-o

So, so how 'bout the details, eh? B'fore ma cheese gets all moldy and the apple knockers get at it... Or should I get Heikki Lunta after you, eh?

AZgazer
2004-May-08, 10:20 PM
It's about 0430 on a Sunday morning and I am going back to KI. I was in my Mustang 5.0 and like most 20 year olds I liked to drive fast. :) Well on this morning as I was coming into Marinette WI, I was passed by a semi going a lot faster than me. :o I usually travel about 10ish over the speed limit and this truck blew by me. Truckers typically don't go that fast unless they have a good radar detector and CB and more importantly know the road ahead is clear of cops. OK, so I am about 6 hours into my 8 hour drive on a Sun. morning and this truck blows by me... what am I to do? Why follow him for as long as possible of course. :wink: We enter Marinette and he's still maintaining close to 60 mph which was a little much for me. :( So I actually backed down to about 45-50 mph (posted limit was 30 mph) when we are coming around a corner and about to enter the last stretch to Menominee MI. (Marinette WI & Menominee MI are about 10k people each and sit on opposite banks of the Menominee (?) river.) Enough geography, heh... Right as we enter this curve I decide to slow down and catch the truck outside of town... wouldn't Mr. Murphy be with me. :evil: I let off the gas dropping to 45ish and out from behind the grocery store Mr. Small town Officer sees a metallic silver 5.0 blasting through his little town on this fine Sun. morning. #-o I would not be allowed to post anymore here if I put the string of explatives that spewed forth from my mouth as I quickly calculated the fine involved with how much time this was going to cost me. Oh!!! and the realizatin that had I followed the truck at speed I would have been around the corner when the Cop pulled through and would have at best seen my tail lights entering MI. :cry: #-o But not being one to run from the law, I just pulled over and waited for him. (The state line being so close posed potential flight/evasion risks that weren't worth considering driving on until the pulled me over.)

It didn't take long for my rear view mirror to fill with the dreaded red/blue flashing lights. I give him my liscence/insurance and get blasted for 10 minutes on safety & how tickets issued to out of state drivers must be paid in full at the Magistrate (who was going to be pulled out of bed and miss Church to see me) before being let go etc... [-X Finally he goes to his car and comes back after about 5 minutes and gives me my items back telling me "Son, you're lucky. You were going faster than the speed of light and got away with it." :oops: I just shook my head in understanding and put all my items away while he went back to his car.

Actually I had no idea why he said that until I was passing him on the way out of the lot I had pulled over in, he was fidgeting with a Laser speed gun! The only thing I can figure is that due to my speed, the curve of the road and his location he was never able to hit my car with the gun. Laser guns are highly accurate compared to radar, but require a clear line-of-sight and pencil point accuracy, with a radar gun you can get around small objects and a sweep in the general area (assuming no other traffic is around) will yield a result.

So that is how my 5.0 was faster than the speed of light according to an official of the Sate of Wisconsin, or at least from Marinette. 8) About a week later my supervisor coincidentally asked if I had been obeying all the traffic laws, staying under ya know, the speed of light. :o Seems the Base sticker/USAF SP sticker/FOP sticker and the fact I was heading into the U.P. = a "courtesy" call to my Unit. Never was able to find out if his gun was the problem or if he thought my Unit being notified would be punishment enough. A SAC Cop and a Magistrate = REALLY bad news for the member involved. But since we'll never know, I can claim I had a car faster than the speed of light! 8)

Maksutov
2004-May-10, 11:12 PM
AZ,

That's some story. You know, coming into Marinette from the south on 41 is no picnic, as it narrows down and starts to twist and turn through the old downtown. Well, at least you survived.

In an earlier post you wrote, "It wasn't civilization until you hit Milwaukee! and even that was questionable." Here's (http://news.yahoo.com/news?tmpl=story&u=/ap/20040510/ap_on_sp_ba_ne/bbn_sausage_assault_3) a story you should get a kick out of.

BTW, ever overshoot Green Bay and wind up at Williams Bay? They've got this really big refractor down there made by the Clark Bros. many years ago. Its objective is 40 inches in diameter and is housed in a place called Yerkes Observatory. 8)

AZgazer
2004-May-11, 03:06 AM
Hehe, yeah I never said 20 year olds with fast cars were smart. #-o I would in my defense point out that I slowed down due to the conditions. :P

That link was killer. My fiance is a huge Cubs fan. :evil: (Bigger Cardinals fan here 8) ) Anyways the Cubs picked up Randall Simon (The sausage slugger.) and I give her grief whenever possible about that story. The Bravery Award is now added to my arsenal!

I haven't been to the U.P. in years but am planning a return trip before I move back to AZ later this year. I wrote down that observatory info and will definately try and add it to the trip. THanks. :)

JohnOwens
2004-May-13, 08:00 AM
I haven't been to the U.P. in years but am planning a return trip before I move back to AZ later this year. I wrote down that observatory info and will definately try and add it to the trip. THanks. :)
FYI, the Yerkes observatory he mentioned isn't north from GB, like the sentence could have been taken to mean ("overshoot" is kind of vague). It's right near the Illinois border, in southeast Wisconsin, on Lake Geneva if that means anything to you (besides the Swiss one). Probably easier to make a separate trip for it, than to do it on the way to the UP.

AZgazer
2004-May-13, 06:46 PM
FYI, the Yerkes observatory he mentioned isn't north from GB, like the sentence could have been taken to mean ("overshoot" is kind of vague). It's right near the Illinois border, in southeast Wisconsin, on Lake Geneva if that means anything to you (besides the Swiss one). Probably easier to make a separate trip for it, than to do it on the way to the UP.

Oh well that changes things drastically, I had taken it the Observatory was well into Wisconsin. I am in Champaign and I usually poke around greater Chicago every other month or so. Will definately have to get some info on it, we are thinking of going to one of the Stl@Chi games in 3 weeks so I will be in that area pretty soon.

AZgazer
2004-May-13, 06:49 PM
In case anyone else is interested in the Yerkes Observatory (http://astro.uchicago.edu/yerkes/) here is some info on it. :D

Kaptain K
2004-May-14, 12:10 PM
If anyone tries to tell you that astronomers don't have a sense of humor, just show 'em this:

http://astro.uchicago.edu/vtour/40inch/spiderman.gif :wink:

Tensor
2004-May-14, 02:44 PM
AZ,
BTW, ever overshoot Green Bay and wind up at Williams Bay? They've got this really big refractor down there made by the Clark Bros. many years ago. Its objective is 40 inches in diameter and is housed in a place called Yerkes Observatory. 8)

Been there, several times. I was born and raised in Kenosha. As for summers.... we had a nice summer the year I was stationed in Iceland. Unfortunately, I had to work that weekend. As for real stuff, the year I was there the last snow, from the previous winter, was finally gone around the end of June.