[1.8x - 1.11x] Kerbal Weather Project (KWP) v1.0.0 (2024)

While KSP simulates atmospheres with variable depths and densities it lacks dynamic weather limiting its utility as tool for exploring concepts in atmospheric science. Kerbal Weather Project was developed to remedy this. In KWP, weather and climate data from a state-of-the-art global circulation model was incorporated into KSP gameplay. This was accomplished through aglobal hourly climatology, enabling players to experience diurnal and spatial variations in atmospheric conditions. In addition, point weather data is provided forKerbin launch sites, giving players the option of experiencingdynamic weather conditions that change from day to day. KWP features a text-based GUI showing remotely sensedweather data (in space) and in situ weather data (in the atmosphere).

Compatibility

KWP works with stock KSP and should work with the vast majority of KSP mods. KWP has been tested, without major issues, in a KSP 1.10 playthrough with 220 other popular KSP mods. That said, KWP may conflict with mods likereal heat that modify the stock game's aerodynamic or thermodynamic system. KWP can still be used with these mods as KWP's override of the stock thermodynamic system can be disabled in the settings menu.

KWP is compatible with the aerodynamics overhaul: Ferram Aerospace Research (FAR). Note that since FAR overrides KSP's thermodynamic system, pressure and temperature data from KWP will not affect flight dynamics when FAR is installed. Note that FAR may not be compatible with the latest version of KSP.

Background
Kerbin weather and climate analyseswere produced using the Model for Prediction Across Scales (MPAS; Skamarock et al., 2012) a state-of-the-art atmospheric general circulation model developed by the National Center for Atmospheric Research (NCAR).

MPAS was run for six-years (1st year: spin-up) at a resolution of 2 x 2 decimal degrees. Fortunately, Kerbin’s atmosphere has the same chemical composition as Earth’s.In MPAS, terrain and biome data from KSP were used to classify land use, vegetation type, green fraction, and other geographical datasets.

In addition to land surface modifications, several changes to MPAS were made to enable more realistic simulations of Kerbin's atmosphere. These changes are listed below:

• Axial obliquity was set to zero.
• Orbital eccentricity was set to zero.
• The solar constant was set to1360 W/m²
• The day length was set to sixhours (21600 s)
• The Coriolis parameter was multiplied by four.

An hourly global climatology of Kerbin was developed by averaging the results of the five-year MPAS simulation,bythe hour. Results from this simulation were incorporated into the game via KWP.

Required Mods

• Toolbar Controller
• Click Through Blocker
• ModularFlightIntegrator

Recommended Mods

• Kerbinside Remastered- adds launch sites compatible with KWP.
  • Note that the lite version of KWP does not include weather data at Kerbinside launch sites.
• KerBalloons - Launch weather balloons!
• Atmospheric Autopilot- makes flyingduring windy conditions a little easier.

Downloads and Installation Instructions

Full Version (84 MB):High resolution climatology, 5-years of weather dataat stock and Kerbinside launch sites.

GitHub:https://github.com/cmac994/KerbalWeatherProject/tree/master

Spacedock:https://spacedock.info/mod/2607/Kerbal Weather Project

Lite Version (13 MB):Low resolution climatology, 1-year of weather dataatstock launch sites.

GitHub:https://github.com/cmac994/KerbalWeatherProject/tree/lite

Spacedock:https://spacedock.info/mod/2611/Kerbal Weather Project - Lite

See the links above forinformation on how to install KWP. Alternatively, you can just use CKAN.

KWP Animations

Weather Animations

Simulated Infrared (IR) Satellite Imagery for Kerbin (Each Frame = 1 day)

Light colors = high cloudsorcold surface;Dark colors= low clouds or warm surface

Precipitable Water (PW) onKerbin (Each Frame = 1 day)

Note vortices of high PW in tropics... those are tropical cyclones (hurricanes)!

Upper level winds on Kerbin(Each Frame = 1 day)

Surface Temperature on Kerbin(Each Frame = 1 day)

ClimatologicalAnimations

Average Temperature by Height

Average Wind Speed by Height

If the above charts are bit challenging to decipher check out the chart interpretation page on the mod webpage.

KWP Gameplay

A crewed weather balloon beingcarriedaway from the launchpad by northeasterly trade winds.

An uncrewed glider flies into a strong headwind and ends up traveling retrograde!

A polar orbiting satellite passes over the KSC providing remote sensing weather data along its track

SRB Recovery withand without wind.

Additional Information

For more screenshots, animations, and information about KWP check out the officialmod webpage.The science behind KWP, as well as its potential as an educational tool, will be presented at the 101st Annual Meeting of theAmerican Meteorological Society (AMS)in January 2021. A link to the AMS poster presentationis provided here. In addition to weather and climateanalysis, the mod webpage providesseveraldemonstrationsdetailing the effects of KWP onatmospheric flight and reentry. A series of short-stories are also included to highlight howKWP can be used for both shenanigansand serious science!

What KWP Does:

• Adds climate and weather data to the stock game
  • Climate data varies geographically, vertically,and diurnally.
  • Point weather data varies with height and time and is valid only for a fixed location.
• Modifies air pressure, density, and temperature on Kerbin affecting the aerodynamics and thermodynamics of flight.
  • The scale height of the KWP atmosphere is higher (8.5 km) than in the stock atmosphere(5.6 km). Consequently, air pressure and density will decrease more slowly with height when playing with KWP enabled. This makes re-entry and SSTOs a little more challenging. As noted above, if you'd prefer KWP not affect KSP aerodynamic and thermodynamics thiscan be selected in the KWP settings menu.
• Provides a text-based GUI for visualizing ambient weather, vehicle velocity, ground track, vehicle relative winds, and aerodynamic variables (e.g. mach number, shock temperature, etc.)

What KWP Does NOT Do:

• At present, KWP does not add any parts or new visual effects to the game. KWP provides a framework for understanding what the weather on a planet with Kerbin's geography and orbital characteristics might look like. The results of the MPAS simulations (detailed on the mod webpage) could provide inspiration for fellow modders to create more realistic cloud cover and visual effects for Kerbin.
• KWP does not include orographic circulations or other small-scale circulations (e.g. thunderstorm cells). This is a limitation of the coarse resolution MPAS simulations from which KWP was derived. In KWP vertical wind speeds are typically very small (< 1 m/s) so unfortunately, aspiring glider pilots will not be able to stay aloft indefinitely by riding the wind.

Future Work

KWP provides a framework for implementing weather in the stock game. A rudimentary weather and climate API has been included with KWP. With this foundation laid it is my hope that real-world science missions, like the Global Precipitation Measurement Mission (GPM) and the Geostationary Operational Environment Satellite (GOES-R), could one day be emulated in KSPor KSP2. Modssuch as SCANSat and Orbital Survey Plus may be one way to realize this concept in KSP, by facilitatingthe mapping and visualization of climate data for science. Other possibilities include real-time charting or logging of weather balloon sounding data, similar to what is performed twice daily here on Earth. These pursuits could serve as educationaltools for teaching basic concepts in atmospheric science.

Acknowledgements

• KSP Developer Squad and KSP creator Felipe Falanghe.
• KSP modding community - specifically forum users @linuxgurugamer, @JoePatrick1, @Fengist, @DaMichel, @NathanKell, and @DMagic. These mod developers, by publishing their code publicly, provided a valuable teaching tool which facilitated many of the advancements implemented in KWP. Without their prior work, incorporating weather data into KSP would have been exceedingly difficult.

License: MIT