Facebook

Login

Support Sailonline

If you haven't already - join the SAILONLINE YACHT CLUB!

Please also consider making a donation - all amounts are greatly appreciated!

Board » General Discussion » Weather - Brain Storm

Page: Previous 1 2 3

Posted by
Zorba777


Users avatar

Posts
67
Registered at
2020-06-06 08:22:54
2020-10-01 11:28:14 - Re: Weather - Brain Storm
@dtayls @Vlbex Good comments. This is exactly what I hoped to see in this discussion. As weather models and routing software become more accurate the human factor in SOL races would become smaller and smaller. That's not what we want. I think we all enjoyed the recent Melbourne to Osaka race because we had to deal with many unexpected WX changes and a lot of position changes. High WX uncertainty = more interesting race. Compare that to the current Darwin to Perth race, where the weather has not changed at all. There is hardly any new message on the chat, people just set their DCs for the next 24 hours and nothing happens. If WX becomes more reliable then we will get more Darwin to Perth type races, an fewer races like Osaka, where we all had problems and scenario changes to deal with.
There is probably still a few years time until WX models become too good, but we can already exchange ideas on how SOL could adapt to that if needed.

I think what most of us want is a realistic simulation, not just a "who has the best routing software" type competition where all you have to do is execute the ideal route. In real life sailors have to deal with real weather differing from what the WX update forecasted. Can we mimic something like that in SOL? And if so how?

Introducing a random factor that makes the grib we play differ a bit from the official GFS (or other) weather model was suggested. Personally I am not a fan of using random factors. The reason is that the people who implement or help to run SOL behind the screens are volunteers and often participants at the same time. There would always be a suspicion that insiders have knowledge (or access) to those random factors, while normal players can not see them.

So, *IF* any "random factors" are to be used to add uncertainty (and thus stop routers from finding optimal solutions/routes) then those random factors should come from the weather itself imo. For example, as the article I linked to mentions, there will be more access to near-real time weather data (from drones and buoys) in the future. Let's say we have a race in an area using GFS data as we currently do. Every 6 hours we have a fixed map that we sail. But if there are a few buoys in the given area that put real time wind data on internet then we could use those real time data to change the weather map we use in SOL every hour or every 2 hours. That could be as simple as adjusting all wind speeds on the basis of the difference between predicted wind speed and measured wind speed for the given locations and times. That's isn't to hard on the server as it is only done once and hour. But it would add uncertainty. And we can experiment how much weight we give to the real-time data, so that routing keeps some of its use, but adapting to changes in real weather becomes important too. If we do that we will have a much more realistic simulation, because that's what IRL sailors do too. :-D

Posted by
Zorba777


Users avatar

Posts
67
Registered at
2020-06-06 08:22:54
2020-10-01 11:36:37 - Re: Weather - Brain Storm
An other way to add uncertainty is by introducing a random factor that depends on the SOLers actions. The best candidate for that would be "wind shadow" that is caused by the other boats near you in the direction where your wind is coming from. When you are sailing in "dirty wind" your boat slows down a bit. This is also the case IRL sailing. By assigning a certain performance loss % if another boat is putting me in dirty wind, we would create uncertainty and introduce the sailing tactics that are know from real races.
I think this factor should be quite small to keep it practical. Maybe 98% performance if you are in wind shadow from another boat, we would need to test what works. This would cause boats to avoid wind shadow by moving away from the optimal routes that their routers crank out.
I think this would be very interesting, but more so for the short races and sprint races. In long ocean races it should be a very small factor (or not useful at all).

--- Last Edited by Zorba777 at 2020-10-01 11:38:14 ---
Posted by
dtayls


Users avatar

Posts
30
Registered at
2014-06-23 03:34:16
2020-10-03 04:34:24 - Re: Weather - Brain Storm
I agree with you @Zorba that "random factors should come from the weather itself".

As you know I like the idea of using a different and more accurate model (perhaps ECMWF) for the underlying simulation but that might depend on gaining access to a high quality model to which most users do not have access.

Another approach might be to introduce a certain degree of randomness in to the simulation's weather model, but what should the source of this randomness be?

One option would be to choose a random mix of two or more models. This could be (a) fixed for the whole race or (b) change over time or (c) vary by lat&lon across the GRIB or (d) both meaning <x,y,t>.

If model volatility or uncertainty GRIBs were available then this could also be used to add a little to the randomness model but I suspect many would consider this to be a step too far :-)

Page: Previous 1 2 3

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Cross the Convergence 2026 - Samoa to Hawaii


The second race of our new series of ocean voyages across the World’s convergence zones, takes us northward again up the Pacific Ocean, now from Samoa at 13.5 degrees South, across the Equator to Hawaii, famed for its breaking surf and active volcanoes, on the edge of the Tropic of Cancer at 19.5 degrees North. It’s 2300nm, so we’ll take our very steady Steinlager II. Race #1982
INFOby brainaid.de
Steinlager IIPARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: CCZ - SYC
Race starts: Feb 06th 18:00 Registration Open!
▶ Flash
GO TO RACE

Beketov by Balloon 2026 - In Siberia


Way-back-when France and England, and Spain as well, were squabbling about who should control what of North America, only to lose the most of it to their own insurging colonists, their eastern European neighbour empire, Russia, was quietly assimilating vast, thinly nomadically populated territory of its own – Siberia! Amongst the many explorers and adventurers that served Russia so well in these conquests was the Cossack hetman Pyotr Beketov. Let’s pretend we’re he and eschewing horseback, let’s travel by balloon from Yekaterinberg to Krasnoyarsk – just a short 2000km (1100nm) section of the Trans-Siberian Express’ 9289km!
Race #1972
INFOby brainaid.de
SOL Balloon PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: BOL - SYC
Race starts: Feb 03rd 13:00 Registration Open!
▶ Flash
GO TO RACE

West Papua to Oregon 2026

Our next race in our Ocean Championships is the first of a series of great natural migrations we will track in 2026. The leatherback turtle is the most widely distributed marine reptile on planet Earth, and chooses to breed in warm tropical waters, but prefers to forage in more temperate habitats, travelling thousands and thousands of miles effortlessly annually to maintain this way of life. Our race will follow one of the typical trips of this turtle, from breeding grounds in the seas off West Papua to the coast of Oregon. It’s only 5900nm, so to keep up, but in comfort, we’ll follow in our Gunboat 90.
Race #2006
INFO by brainaid.de
GB 90 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ1 - OCCH - MIG - SYC
Race starts: Feb 02nd 11:00 Registration Open!
▶ Flash
GO TO RACE

Race to Up Helly Aa 2026

A-OI!!! The fiery spirit of Shetland’s legendary Up Helly Aa returns, and Sailonline’s annual race to Lerwick is once again upon us. Covering 383 nautical miles from Aberdeen, SOLers will tackle winter waters steeped in Viking tradition. This year, we race the classic Frers 33, a proven cruiser-racer born from the golden era of offshore racing and still a sturdy performer both on the virtual and real water. Can you master the course and reach Lerwick in time for the flames?

SAILING NOTE: Gruney may be approached from any direction but must be passed for rounding purposes as indicated on the chart.
Race #2005
INFO by brainaid.de
Frers 33 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
SYC
RACE CLOSE: Friday,
February 6 at 2300 UTC.
Race starts: Jan 30th 17:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member KaSToR
  2. Sailonline Yacht Club Member WRmirekd
  3. Sailonline Yacht Club Member CriticalHippo
  4. Sailonline Yacht Club Member rafa
  5. Sailonline Yacht Club Member rumskib
  6. Sailonline Yacht Club Member Sax747
  7. Sailonline Yacht Club Member vida
  8. Sailonline Yacht Club Member bonknhoot
  9. Sailonline Yacht Club Member Kipper1258
  10. Sailonline Yacht Club Member Panpyc

View full list

Series

Mobile Client

SYC members have the benefit of access to our mobile/lightweight web client!

The mobile client