U.S. CitiesCity-Data Forum Index
Go Back   City-Data Forum > General Forums > Weather
 [Register]
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
View detailed profile (Advanced) or search
site with Google Custom Search

Search Forums  (Advanced)
Reply Start New Thread
 
Old 05-21-2012, 10:05 AM
 
Location: Laurentia
5,593 posts, read 7,385,987 times
Reputation: 2436

Advertisements

Since this didn't belong in any other topic I know of, I thought it prudent to create a new one. Basically this thread will catalogue and discuss the seasonal lags of climates worldwide. For those who are so inclined we can even throw in some fantasy climates.

Nei may beg to differ , but I consider the standard seasonal pattern to be this:

January is the coldest month
July is the hottest month
February is the same as December, March is the same as November, October is the same as April, et cetera

The true seasonal lag is the lag in heating between land or sea and the strength of the sun. This would be a bit complex to figure out, not to mention putting all of Earth in a lagging state, so I concocted this "standard model". Although it may not be the most common pattern, I think this is the one that should be used in our calculations here, since it is easy to figure out the difference in mean temperature between October and April (simple subtraction), whereas a maritime baseline would be more complex. It also enables us to pick out the leading climates that follow the temperature of the land from the lagging climates that follow the temperature of the sea.

To figure out the seasonal lag of a place, one takes the mean temperature of a given spring month, and subtracts it by the mean temperature of its equivalent autumn month (example: April Mean minus October mean). One has a seasonal lag figure. If there is a lag it will show up as a negative number. Since we're cataloging lagging here, it would be advisable to flip the signs, so that a lag is positive and a lead is negative, i.e. greater lags show up as greater numbers. Since January and July are their own equivalents on the calendar in this model, there can be no figures for them.

The results of this prove interesting, and reveal how "laggy" a climate is.

I have already done this for a few cities. A lag is a positive number and a lead is a negative number:

New York, New York:

Feb-Dec: +2.25F
Mar-Nov: +5.25F
Apr-Oct: +3.9F
May-Sep: +5.6F
Jun-Aug: +3.8F

Nashville, Tennessee:

Feb-Dec: -1.3F
Mar-Nov: -0.2F
Apr-Oct: +1.3F
May-Sep: +4F
Jun-Aug: +3F

Fairbanks, Alaska:

Feb-Dec: -2.15F
Mar-Nov: -8.85F
Apr-Oct: -8.2F
May-Sep: -4.25F
Jun-Aug: -3.45F

Chicago, Illinois:

Feb-Dec: -0.1F
Mar-Nov: +2.5F
Apr-Oct: +3.7F
May-Sep: +5.6F
Jun-Aug: +3.15F

Urumqui, Uyghyr Autonomous Region, China:

Feb-Dec: +1.05F
Mar-Nov: -1.1F
Apr-Oct: -4.1F
May-Sep: 0F
Jun-Aug: +1.8F

And for kicks, my fictitious dream climate:

Feb-Dec: -0.7F
Mar-Nov: -0.2F
Apr-Oct: -3.7F
May-Sep: -3.3F
Jun-Aug: -1F


I'd like for us here to post lag figures for real-world climates, and I'd like for posters here to do the math for their fantasy climates. The differences should be interesting .

There is something more or less related to this called the Index of Oceanicity. It was developed by someone named Kerner if I'm not mistaken. The formula is as follows:

Oceanicity = 100((TOct-TApr)/(TRange))

The TOct is the mean temperature for October in degrees Celsius, and the TApr is the same for April. TRange is the difference between the means of the hottest and coldest months in degrees Celsius.

If you're so inclined, you can copy the right side of the equation, and if you plug in the relevant numbers Google or WolframAlpha can calculate it.

The results of this formula applied to the cities mentioned above are likewise interesting. Below are the oceanicity index figures for them:

New York City: +8.81
Nashville: +3.02
Fairbanks: -23.06
Chicago: +7.13
Urumqui: -6.36

My dream climate: -6.29


I would appreciate any additional input. Mean temperatures aren't the only thing one can profile. The occurrence of atypical heat waves or cold snaps over the course of a year can be another metric. A shining example of this would be Whitehorse. Although mean temperatures don't display this much of a lead, the second-hottest temperature ever recorded occurred in the month of May. The hottest ever recorded occurred in June, and July and August's record highs come in third and fourth, respectively. A lesser example of this would be the difference between springtime record highs of Nashville and New York. Despite averaging 10F warmer in April, Nashville's monthly record high of 91F falls short of NYC's record of 96F.
Rate this post positively Reply With Quote Quick reply to this message

 
Old 05-21-2012, 10:20 AM
nei nei won $500 in our forum's Most Engaging Poster Contest - Thirteenth Edition (Jan-Feb 2015). 

Over $104,000 in prizes has already been given out to active posters on our forum and additional contests are planned
 
Location: Western Massachusetts
46,080 posts, read 48,872,416 times
Reputation: 15088
How well would this apply for a climate with extreme lag? Seasonal cycle for San Francisco is unbalanced and not centered around July at all.

San Francisco (Mission District):


Feb-Dec: -1.9°F
Mar-Nov: -1.4°F
Apr-Oct: +5.1°F
May-Sep: +4.7°F
Jun-Aug: +2.0°F

Seems to work ok. Wonder what's the cause of the winter seasonal lead? Rainy season making it cooler in early winter is my guess.
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-21-2012, 11:18 AM
 
933 posts, read 1,949,008 times
Reputation: 646
How about you do one for Barrow, Alaska?
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-21-2012, 01:17 PM
 
Location: Laurentia
5,593 posts, read 7,385,987 times
Reputation: 2436
Quote:
Originally Posted by nei View Post
San Francisco (Mission District):
[...]
Seems to work ok. Wonder what's the cause of the winter seasonal lead? Rainy season making it cooler in early winter is my guess.
That is a plausible explanation. However, it is quite common for Western climates to display a seasonal lag in summer (Aug about the same as July) and then display a seasonal lead in winter (Dec the same as Jan) .

Quote:
Originally Posted by Kaul View Post
How about you do one for Barrow, Alaska?
Done:

Feb-Dec: +6.5F
Mar-Nov: +13F
Apr-Oct: +17F
May-Sep: +11.25F
Jun-Aug: +5.9F

Oceanicity Index: +30.2
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-21-2012, 01:26 PM
nei nei won $500 in our forum's Most Engaging Poster Contest - Thirteenth Edition (Jan-Feb 2015). 

Over $104,000 in prizes has already been given out to active posters on our forum and additional contests are planned
 
Location: Western Massachusetts
46,080 posts, read 48,872,416 times
Reputation: 15088
Quote:
Originally Posted by Patricius Maximus View Post
Nei may beg to differ , but I consider the standard seasonal pattern to be this:
I do disagree, but as long as we have one consistent standard we should be able to compare seasonal lag and lead just as well.

Another idea to compare seasonal lag/lead is to mark the date of the coldest and warmest day and night of the year for each climate. If the shoulder season behave oddly (for example, very slow warmup and then fast warmup) then it won't be as informative but otherwise might be a simple and elegant method.

San Francisco:

Coldest Max: 57.0F (Jan 2)
Coldest Min: 45.6°F (Jan 1)
Warmest Max: 71.8F (Oct 1)
Warmest Max: 55.9°F (Sep 6)

New York City:

Coldest Max: 38.9°F (Jan 24)
Coldest Min: 26.3°F (Jan 26)
Warmest Max: 85.6°F (Jul 22)
Warmest Max: 69.5°F (Jul 26)

Nashville:

Coldest Max: 47.3°F (Jan 14)
Coldest Min: 28.5°F (Jan 24)
Warmest Max: 90.1°F (Jul 22)
Warmest Max: 70.3°F (Jul 22)

You wouldn't have been to tell for sure that Nashville has a significant winter lead. The timing of the coldest day and night isn't too far apart from NYC but once the sun gets stronger Nashville heats quickly and NYC doesn't.
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-21-2012, 01:31 PM
 
Location: Buenos Aires, Argentina
5,929 posts, read 9,746,167 times
Reputation: 4447
what would be the seasonal lag of BA?
and of mar del plata?
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-21-2012, 06:09 PM
 
Location: London, UK
2,702 posts, read 5,824,837 times
Reputation: 1734
Oceanicity :

Nice : 100(3.8/14.5) = 100(0.25) = 25
Hong Kong : 100(2.9/12.5) = 23.2
Singapore : 100(0.5/1.55) = 32.0

My ideal climate : 100(0.6/6.3) = 9.5
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-22-2012, 01:00 AM
B87
 
Location: Surrey/London
11,786 posts, read 9,431,358 times
Reputation: 3067
London

Feb-Dec: -0.4F
Mar-Nov: -0.7F
Apr-Oct: -3.8F
May-Sep: -4.2F
Jun-Aug: -4.1F
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-22-2012, 04:13 AM
 
Location: Laurentia
5,593 posts, read 7,385,987 times
Reputation: 2436
You need to flip the sign for London from negative to positive .
Rate this post positively Reply With Quote Quick reply to this message
 
Old 05-22-2012, 04:31 AM
B87
 
Location: Surrey/London
11,786 posts, read 9,431,358 times
Reputation: 3067
London's oceanicity:

Oceanicity = 100((12-9.9)/(13.5))

= 16
Rate this post positively Reply With Quote Quick reply to this message
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.

Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.


Reply
Please update this thread with any new information or opinions. This open thread is still read by thousands of people, so we encourage all additional points of view.

Quick Reply
Message:


Over $104,000 in prizes was already given out to active posters on our forum and additional giveaways are planned!

Go Back   City-Data Forum > General Forums > Weather

All times are GMT -6.

© 2005-2022, Advameg, Inc. · Please obey Forum Rules · Terms of Use and Privacy Policy · Bug Bounty

City-Data.com - Contact Us - Archive 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37 - Top