Why does a hot spring steam more on a cold day?

Visible steam is driven by the temperature and vapor-pressure gap between the water and the surrounding air, not by the water's absolute temperature alone. A wider gap — cold, dry, windy air over warm water — evaporates and condenses more water vapor into visible mist, which is why hot springs often look steamier in winter than in summer even at the same water temperature.

What determines the pool's equilibrium temperature?

The water settles wherever geothermal heat input balances heat lost to convection and evaporation. Raise the heat flux or cut the wind and losses shrink, so the pool heats up; raise wind speed or drop the air temperature and losses grow, cooling the pool back down, exactly like the energy-balance equation in the simulation.

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Hot Spring Geothermal Steam (2D)

A 2D energy-balance lab: geothermal heat flux, air temperature, wind and pool area feed a real thermodynamic model — water temperature and visible steam respond to the physics live, instead of playing a fixed loop.

Energy & Thermodynamics2DModerate60 FPS📱 Mobile-adapted⇄ 3D version

This 2D companion replaces the 3D version's fixed ambience with an actual energy-balance model: geothermal heat flux warms a pool of a given surface area against convective loss (which grows with wind) and evaporative loss computed from the water-to-air vapor-pressure gap, so the pool's temperature and how much steam is visibly rising are both outputs of the physics, not a preset animation. It reproduces the real hot-spring effect where the steam plume gets thicker on cold, windy days even though the water itself hasn't gotten any hotter.

⚙ Under the hood

Energy balance each frame: geothermal input minus convective loss (h·A·ΔT, h scaling with wind) minus evaporative loss (mass-transfer coefficient × vapor-pressure gap via the Magnus formula × latent heat) sets dT/dt for the pool; steam-particle spawn rate is driven directly by the computed evaporation rate.

geothermal steamevaporationheat balanceconvectionthermodynamics

2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install