earths 0.0.1

High-fidelity Earth simulation engine — orbit, atmosphere, geology, hydrology, biosphere, terrain, lighting, rendering, satellites, and temporal systems with full scientific coupling
Documentation 
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use sciforge::hub::domain::common::constants::SIGMA_SB;
pub struct Lake {
    pub name: &'static str,
    pub surface_area_km2: f64,
    pub max_depth_m: f64,
    pub volume_km3: f64,
    pub elevation_m: f64,
}
impl Lake {
    pub fn mean_depth_m(&self) -> f64 {
        self.volume_km3 * 1e9 / (self.surface_area_km2 * 1e6)
    }
    pub fn shoreline_development_ratio(&self, shoreline_km: f64) -> f64 {
        shoreline_km
            / (2.0 * std::f64::consts::PI * (self.surface_area_km2 / std::f64::consts::PI).sqrt())
    }
    pub fn residence_time_years(&self, outflow_m3_s: f64) -> f64 {
        self.volume_km3 * 1e9 / (outflow_m3_s * crate::SECONDS_PER_YEAR)
    }
    pub fn thermal_stratification_energy_j(&self, surface_temp_c: f64, bottom_temp_c: f64) -> f64 {
        let rho = crate::FRESHWATER_DENSITY;
        let cp = *crate::CP_FRESHWATER;
        let dt = surface_temp_c - bottom_temp_c;
        let volume_m3 = self.volume_km3 * 1e9;
        0.5 * rho * cp * volume_m3 * dt
    }
    pub fn evaporation_rate_mm_day(
        &self,
        air_temp_c: f64,
        water_temp_c: f64,
        wind_speed_m_s: f64,
        humidity: f64,
    ) -> f64 {
        let es_water =
            crate::ARM_A * (crate::ARM_B * water_temp_c / (water_temp_c + crate::ARM_C)).exp();
        let ea = humidity / 100.0
            * crate::ARM_A
            * (crate::ARM_B * air_temp_c / (air_temp_c + crate::ARM_C)).exp();
        let penman_factor = (es_water - ea) * (1.0 + 0.536 * wind_speed_m_s);
        penman_factor * 0.35
    }
    pub fn longwave_radiation_w_m2(&self, water_temp_c: f64, emissivity: f64) -> f64 {
        let t_k = water_temp_c + crate::CELSIUS_TO_KELVIN;
        emissivity * SIGMA_SB * t_k.powi(4)
    }
}
pub fn baikal() -> Lake {
    Lake {
        name: "Lake Baikal",
        surface_area_km2: 31_722.0,
        max_depth_m: 1642.0,
        volume_km3: 23_615.0,
        elevation_m: 455.5,
    }
}
pub fn superior() -> Lake {
    Lake {
        name: "Lake Superior",
        surface_area_km2: 82_100.0,
        max_depth_m: 406.0,
        volume_km3: 12_100.0,
        elevation_m: 183.0,
    }
}