Topic: Severe Mistake in Gamemaster Law

[arakish]

Just recently purchased Gamemaster Law.  While reading in section 19.0 GM Tips, Tricks, and Traps, specifically section 19.7.1 Wind Chill, I noticed the chart in Gamemaster Law is severely wrong.  Investigated on the NOAA internet site and found I was right.  Below are two screen captures showing the comparison.





rmfr

[markc]

 I can not atest to the writing of GM Law but two things come to mind. The first is they may not have been trying to simmulate reality as close as possible so they manipulated the chart in some way. The second is that they may have been using an old source for there data. The book I have as a PDF says 1995 so I suspect that it was writen in 93 or 94 but that is just a guess.

BTW, thanks for the chart I am going to put it in my GM binder to use.

MDC

[edxs]

There was a significant change to the wind chill formula in 2001. I imagine the writers of GM Law couldn't see into the future

Edit: And, after checking the old wind chill numbers, they couldn't see the present either. These numbers don't match up to either.

I finally went and read GM Law, and after reading the text, they are actually the difference between ambient temperature and wind chill. I don't know why they chose to do that, but it isn't wrong in the end.

[arakish]

At rpgrm forums, a compatriot pointed out this:

Someone has got far too much time on their hands...

The table really isn't that far out... The RM table gives a modifier to the temp, rather than the actual temp (which is what the 2nd chart does). Yes, there are some minor discrepancies between the two but from the point of gaming info I think it does the job just fine..

Reading the bolded part above, I went back and read the wind chill section again.  I typed in the section verbatim.

"When the temperature drops below 35? the wind begins to affect the effective temperature. Cross index the low temperature for the day (use the nearest value that is not less than the actual low temperature) with the average wind speed for the day (using the value that does not exceed the actual average wind speed). The result will reveal the modifier for the low temperature (resulting in an effective temperature for the day). Note that wind speeds less than 5 mph have no significant effect on the actual temperature."

And you're right GB.  If you subtract the modifier from the temperature at the top, you get the actual temperature.  My bad, I should have read it more thoroughly.  Thanks for pointing that out.  However, the only modifier that is correct is the very first one in the upper left corner (-2).  After that, as ob1knorrb said, they must have used the old wind chill factor chart.

Here is a spreadsheet I made using the new revised equation.  It carries temperatures down to -80 and winds up to 80mph.  This is in degrees Farenheit and wind speeds are in miles per hour.  I carried this table out this far because the coldest I have ever seen it (when we went on resupply mission to Anuk, Greenland) is an air temp of -70?F and winds up to 40mph, giving a wind chill factor of -126?F.  -126?F is cold enough to cause literal instantaneous frostbite and could freeze diesel fuel solid.

rmfr

Within my quote there is a link to spreadsheet I created using the revised equation.  And here is the link again.  I will be making one for OpenOffice later today.

Here is the NOAA internet site and I found.

Here are some more links from ob1knorrb:

I believe that the tables in Gamemaster Law were based on older Wind Chill tables, and the table you are showing is a revised table.
There is some additional information on this as well as a calculator that can generate old and new values on this site:
http://www.erh.noaa.gov/er/iln/tables.htm

Here is a copy of the old table (although even this doesn't quite match either):
http://www.eol.ucar.edu/homes/rilling/wc_table.html

Good information to know though.

rmfr

[Rasyr-Mjolnir]

1) GM Law is 18 years old.

2) I cannot speak personally about why the table was done in the manner it was done. Nor where they got their data or formula from, but suspect that it was from even older data (from printed books most likely, since the internet was still relatively young back then and very few ICE personel of the time were computer/internet literate) which could have been updated or changed any number of time since then.

3) Rolemaster is first and foremost a game. It was never intended to even closely model reality. Any "realism" to be found in Rolemaster is purely coincidental (and pure serendipity for those who like realism).

4) So the table isn't accurate according to CURRENT data/formulas? Not really a problem. My suggestion?

Chill out! Relax! Enjoy the game....
 

5) You want to use the table arakish posted? Great! Have fun with it!  However, ICE is unlikely to change it, since it has worked well enough for 18 years. IF/WHEN we rewrite the book, or do a variant for HARP or RMC, then we will likely use more up to date data.

[Fenrhyl Wulfson]

Both tables ignore relative air moisture and air pressure (or don't give the information). Those parameters DO have an impact on wind chill. Thus we can't say the GL's one is wrong.

(And anyway, it's a game, not a physics class)

[Arioch]

4) So the table isn't accurate according to CURRENT data/formulas? Not really a problem. My suggestion?

Chill out! Relax! Enjoy the game....
 

Lol 

IF/WHEN we rewrite the book, or do a variant for HARP or RMC, then we will likely use more up to date data.

And Celsius instead of Fahrenheit? 

[Fenrhyl Wulfson]

I second this !

[David Johansen]

Obviously what we need is a comprehensive Weather Law book with the older and newer formula both represented as well as tables for when you are wet at different temperatures and altitudes.

[Arioch]

Obviously what we need is a comprehensive Weather Law book with the older and newer formula both represented as well as tables for when you are wet at different temperatures and altitudes.

I wouldn't make jokes about that if I had the word Playtesters written in red letters under my nickname... after all ICE need to know if those chart are accurate

[yammahoper]

Obviously what we need is a comprehensive Weather Law book with the older and newer formula both represented as well as tables for when you are wet at different temperatures and altitudes.

Well, this is something I would never use.  Basically, it is whatever temperature i say it is.

Far more useful for a temperature table would be one that shows what penalty to activity is suffered fir each race at varying temperatures.

lynn

[dutch206]

Chill out!

  Rasyr made a funny!

[markc]

 You know something I might use this as an idea for a SM adventure on a low tech planet. The court astronomer has his charts from prevous astronomers but it is not as accurate as the PC's tech scanners and shipbased sensors. Either the king/advisers/people thank the PC's or think they have powerfule witchcraft since they came from the stars.

Thanks for the link and all your work as I like it better when my game is more real. The players seam to play it a little more close to the vest.

MDC

[edxs]

I'm thinking about using this as the basis for a simple unified heat index/wind chill/solar radiation system.

Granted, it's 25 years out of date and much less extreme than modern heat index/wind chill, but I am attracted to it because it creates universal formulas for cold and hot.

I've got tables to compute apparent temperature from temperature, humidity, and windspeed. I just need to figure out some way to add in sun exposure without making it unduly complicated. Also, I need to find and set limits for frostbite/heat stroke etc.

[Langthorne]

Just recently purchased Gamemaster Law.  While reading in section 19.0 GM Tips, Tricks, and Traps, specifically section 19.7.1 Wind Chill, I noticed the chart in Gamemaster Law is severely wrong.  Investigated on the NOAA internet site and found I was right.  Below are two screen captures showing the comparison.

Whether or not it is a mistake, I'm not sure that I would describe it as "severe".

If I was going to try to find the appropriate descriptor for this situation, considering level and significance of potential error (for a roleplaying game), I would plump for "minor" or possibly "small ie slightly more important than poor punctuation".

If GM Law was in fact "The Confraternity of Meteorologists' Handbook", I might go for "severe".

I do like the table you posted though (pretty colours, and a guide to how long before wind chill starts to bite).

[lev_lafayette]

3) Rolemaster is first and foremost a game. It was never intended to even closely model reality. Any "realism" to be found in Rolemaster is purely coincidental (and pure serendipity for those who like realism).

I agree with everything you said except for this comment. Even the 1st edition of Rolemaster paraded its realism as being a buying point ("have you ever seen a wolf use a crossbow?". The argument that it's a game and shouldn't try to model reality is what Gary Gygax used to say the Sorcerer's Scroll articles when making up excuses for clear and evident flaws in the game system.

(Such flaws have been since accumulated into their own book - Murphy's Rules)

Of course, this is hardly of the same scale. I don't know anyone who has ever used the Wind Chill chart from GL, except to say "there is a brisk cold wind blowing". It may be an issue if you're on top of a mountain and short of blankets and rations tho'...

Also I think the GL chart is supposed to represent a modification to the "unwindy" temperature, rather than an absolute figure.

[Justin]

Obviously what we need is a comprehensive Weather Law book with the older and newer formula both represented as well as tables for when you are wet at different temperatures and altitudes.

Well, this is something I would never use.  Basically, it is whatever temperature i say it is.

just had to chime in with an "I would!"

[Greyaxe]

Just recently purchased Gamemaster Law.  While reading in section 19.0 GM Tips, Tricks, and Traps, specifically section 19.7.1 Wind Chill, I noticed the chart in Gamemaster Law is severely wrong.  Investigated on the NOAA internet site and found I was right.  Below are two screen captures showing the comparison.

Whether or not it is a mistake, I'm not sure that I would describe it as "severe".

  It is so severe i am going to burn the page out of the book and replace it with the factual facts in this ficticious fantasy manual. Take that

[markc]

 I am starting to wonder about the old Boy Scout books I had back in the 80's and the fact thay most of them were writen in the 50's and 60's and the info I was given to study.

MDC

[Skaran]

Of course if you want an error have a look at the horse heights tables. Have you ever seen a 25 hand high horse? (That would be 8ft 4ins at the shoulder) If you do call it by its correct name "an elephant". How would you get on to such an animal.

I have to admit this is one of my minor beefs. I have owned a Percheron (Heavy norman warhorse) 15 hands high, several Arabs all 14-15 hands (these by the way are equivelant to light warhorses), the original norman warhorse at the time of the conquest was 12 hands.

Perhaps if the GMs companion is redone some reasearch could be done, I like realism in my fantasy games it makes the fantasy elements more believable. Scaling a horse up to 25 hands will do some strange things to its legs if they are to support the poor animals mass.