"Freeze Points" metric

[vvill]

Hi folks,

You may have a noticed a new “Freeze Points” graph under the Individual (Various) leaderboards. This is a sort of experimental metric that’s intended to capture the spirit of riding regularly in the cold, but not necessarily long distances.

Each of your rides is scored based on both the starting temperature of the ride, and your ride distance. Your highest scoring ride of the day is added to your BAFS season total.

However, there are diminishing returns: –
1. You are awarded for riding more up to a “sweet spot” of around about 3-7 miles. You can ride longer of course, but you there isn’t much reward.
2. You are awarded more for rides that start at cold temperatures, especially below freezing temperatures. Between about 38-45F you can’t score as many, but as you get to 32F and below, you get significantly higher scoring rides. Below about 25F the diminishing returns come back into play – as long as it’s around freezing or less, you will add more to your score.

There are no daily ride bonuses and therefore no “sleaze days” in this metric (…although there’s no reason you couldn’t go out at 12:01am each morning and ride 5 miles!) There may or may not be a pointless prize given away based on this. I haven’t spent a lot of time on calibrating/tuning the scoring function so it may be subject to change. Feedback is welcome! Obviously you can “game” your score to some extent, but I think generally it does a decent job rewarding those who ride a non-trivial distance in cold weather on a regular basis which is what I feel BAFS is all about.

Big thanks to hozn (as usual) for adding my code to the website! Temperatures are based on the same data used throughout the site (Weather Underground API).

This shows how many Freeze Points you would get for a range of starting temps/mileages:

The shape is not too dissimilar from the NWS windchill chart although my mileage scale is not linear and I’m not using exponentials. Above 45F you actually get a (small) negative score – I should probably change this to just be 0.

Topic

[ewilliams0305]

@vvill 134945 wrote:

There would be no curves based on mileage/temperature if it was just supposed to gnarliest, because let’s face it, riding 250+ miles in freezing temperatures on Jan 1 would just blow a gnarliest score out of the water (…hi Eric!) Another element was time –

I think it’s also important to factor in “ride time”, something I failed to do with my longest coldest ride award. I realize it’s important to not only reward people for big miles and cold days but also ride time. I think it’s a heck of a lot easier to ride a metric when it’s 20 degrees out if you can ride a metric in 3-4 hours. If this metric took say 4-6 hours it’s safe to say your suffering on a completely different level. Another example, shuby road 109 miles at 21 degrees yielding a score of 5, I have NO doubt this was a lot harder than say riding 6 miles at 0 degrees. I’ll have to start my own thread about this but I think a good measure would be ride time VS temp.

As VVILL noted my 257 mile ride was averaged at 32 (not cold), but after 12 hours of being outside I can tell you I’ve never been this cold in my entire life.

[Rod Smith]

`I like to wait until it warms up. Kudos to those hearty souls wise enough to ride in the middle of the day when the sun is at it’s highest above the horizon.

[BigBaldy]

Noob question – got a Garmin for Christmas…how do you set it up to repport the weather on your rides, especially when linked to Strava? Mostly just interested, I generally wimp out if it’s < 37-38 degrees. Thanks...

[josh]

@BigBaldy 205225 wrote:

Noob question – got a Garmin for Christmas…how do you set it up to repport the weather on your rides, especially when linked to Strava? Mostly just interested, I generally wimp out if it’s < 37-38 degrees. Thanks...

I’m not 100% sure what exactly you’re asking — if it’s related to the Garmin itself, I’m not sure. I have a Wahoo Elemnt Bolt that has a thermometer, and so logs temperature. Strava, as of April 2020, includes weather data for activities for premium subscribers. There are free apps that do similar things, such as Klimat (which I believe has free and premium tiers). This thread is about Freeze Points, which use Dark Sky as the source for weather data (previously Weather Underground). All the other FS weather/temp-related things also work in a similar way I believe. Hopefully this answers your question.

[sszibler]

Does Dark Sky look at the whole ride for freeze points, or like Klimat, just looks at the beginning temps and you get that temp for all your miles?

[merlin]

@sszibler 216426 wrote:

Does Dark Sky look at the whole ride for freeze points, or like Klimat, just looks at the beginning temps and you get that temp for all your miles?

The code believes that it samples the weather data hourly over the entire duration of the ride based on your approximate start lat/long rounded to 1 decimal place, so within 10 miles or so. Temperatures are averaged, precipitation is accumulated and scaled so if you rode 30 minutes you get half of the hour’s precipitation, or if you sat in a coffee shop for 3 hours of a 4 hour ride you’ll get 1/4 the weather. For technical reasons if you do a massive ride starting just before midnight your weather credit will be shortchanged. Some of this could be improved, but the weather data are so unreliable and the code test coverage so non existent, the bearing of any of this on reality is questionable and any improvements would as likely as not not be.

[AlanA]

As someone battling for the ‘reverse’ freeze points this year, I would love to know how the other end of this game works. I was so far ahead a few weeks ago, and now someone is ahead of (below) me.

[merlin]

@AlanA 225471 wrote:

As someone battling for the ‘reverse’ freeze points this year, I would love to know how the other end of this game works. I was so far ahead a few weeks ago, and now someone is ahead of (below) me.

Well, so freeze points is the sum of the daily max of (11*(ATAN((R.distance+4)-2*PI())+1.4)-2.66)*(1.2+ATAN((32-W.ride_temp_start)/5)) which clearly explains how you lost your spot.

[AlanA]

@merlin 225538 wrote:

Well, so freeze points is the sum of the daily max of (11*(ATAN((R.distance+4)-2*PI())+1.4)-2.66)*(1.2+ATAN((32-W.ride_temp_start)/5)) which clearly explains how you lost your spot.

OK, thanks. That clearly sums it up!

[Author]

Replies