indicators.yml

- name: 2m_temperature
  units: degrees Celsius
  description: 2-m air temperature
  offset: -273.15  # Kelvin to degrees C
  bias-correction: offset
  cmip6:
    name: near_surface_air_temperature

- name: precipitation
  units: mm per month
  description: Total precipitation (including snow)
  scale: 2592000  # mm/s to mm / month
  era5:
    name: mean_total_precipitation_rate
  cmip5:
    name: mean_precipitation_flux
  cmip6:
    name: precipitation
  bias-correction: percent

- name: runoff
  units: mm per month
  description: Runoff
  scale: 2592000  # mm/s to mm / month
  era5:
    name: mean_runoff_rate
  cmip5:
    name: runoff
  cmip6:
    name: total_runoff
  bias-correction: percent

- name: evaporation
  units: mm per month
  description: Evaporation
  era5:
    name: mean_evaporation_rate
    scale: -2592000  # change sign, mm / month
  cmip5:
    name: evaporation
    scale: 2592000  # mm/s to mm / month
  cmip6:
    name: evaporation_including_sublimation_and_transpiration
    scale: 2592000  # mm/s to mm / month
  bias-correction: percent

- name: 10m_wind_speed
  units: m / s
  description: Wind speed magnitude at 10 m
  bias-correction: scale
  cmip6:
    name: near_surface_wind_speed

- name: 100m_wind_speed
  units: m / s
  description: Wind speed magnitude at 100 m
  era5:
    compose:
      - 100m_u_component_of_wind
      - 100m_v_component_of_wind
    expression: (_100m_u_component_of_wind**2 + _100m_v_component_of_wind**2)**0.5
  cmip5:
    name: 10m_wind_speed
    scale: 1.6  # average scaling from 10m to 100m, based on one test location (approximate!)
  cmip6:
    name: near_surface_wind_speed
    scale: 1.6  # average scaling from 10m to 100m, based on one test location (approximate!)
  bias-correction: scale

- name: surface_solar_radiation
  units: W / m^2
  description: Solar radiation at the surface (accounts for shadowing from clouds
    and dust, depending on model formulation)
  era5:
    name: mean_surface_downward_short_wave_radiation_flux
  cmip5:
    name: surface_solar_radiation_downwards
  cmip6:
    name: surface_downwelling_shortwave_radiation

- name: relative_humidity
  units: '%'
  era5:
    compose:
      - 2m_temperature
      - 2m_dewpoint_temperature
    expression: 100*(exp((17.625*TD)/(243.04+TD))/exp((17.625*T)/(243.04+T)))
    mapping: {T: _2m_temperature - 273.15, TD: _2m_dewpoint_temperature - 273.15}
  cmip5:
    name: near_surface_relative_humidity
  cmip6:
    # name: near_surface_relative_humidity
    # most models provide specific humidity, but few provide relative humidity
    # (with the exception of CanESM5 (Canada) and GIS-E2-1-G (USA))
    # try to retrieve relative humidity from specific humidity instead
    # source: https://earthscience.stackexchange.com/a/2361
    compose:
      - near_surface_air_temperature
      - near_surface_specific_humidity
      - surface_air_pressure
    expression: 0.263 * surface_air_pressure * near_surface_specific_humidity / exp(17.67 * (T - 273.15) / (T - 29.65))
    mapping: {T: near_surface_air_temperature}
  bias-correction: scale

- name: minimum_monthly_temperature
  units: degrees Celsius
  offset: -273.15
  cmip5:
    name: minimum_2m_temperature_in_the_last_24_hours
  cmip6:
    name: daily_minimum_near_surface_air_temperature
  era5:
    name: 2m_temperature
    frequency: hourly
    transform: 
      - daily_min
      - monthly_mean
  bias-correction: offset

- name: maximum_monthly_temperature
  units: degrees Celsius
  offset: -273.15
  cmip5:
    name: maximum_2m_temperature_in_the_last_24_hours
  cmip6:
    name: daily_maximum_near_surface_air_temperature
  era5:
    name: 2m_temperature
    frequency: hourly
    transform: 
      - daily_max
      - monthly_mean
  bias-correction: offset

- name: frost_days
  units: per month
  cmip5:
    name: minimum_2m_temperature_in_the_last_24_hours
    frequency: daily
    offset: -273.15
    transform: 
      - threshold_negative
      - monthly_count
  cmip6:
    name: daily_minimum_near_surface_air_temperature
    frequency: daily
    offset: -273.15
    transform:
      - threshold_negative
      - monthly_count
  era5:
    name: 2m_temperature
    frequency: hourly
    offset: -273.15
    transform:
      - daily_min
      - threshold_negative
      - monthly_count

- name: minimum_daily_temperature
  units: degrees Celsius
  offset: -273.15
  cmip5:
    name: minimum_2m_temperature_in_the_last_24_hours
    frequency: daily
  cmip6:
    name: daily_minimum_near_surface_air_temperature
    frequency: daily
  era5:
    name: 2m_temperature
    frequency: hourly
    transform:
      - daily_min
  bias-correction: offset

- name: maximum_daily_temperature
  units: degrees Celsius
  offset: -273.15
  cmip5:
    name: maximum_2m_temperature_in_the_last_24_hours
    frequency: daily
  cmip6:
    name: daily_maximum_near_surface_air_temperature
    frequency: daily
  era5:
    name: 2m_temperature
    frequency: hourly
    transform:
      - daily_max
  bias-correction: offset

- name: 2m_temperature_daily
  units: degrees Celsius
  offset: -273.15
  cmip5:
    name: 2m_temperature
    frequency: daily
  cmip6:
    name: near_surface_air_temperature
    frequency: daily
  era5:
    name: 2m_temperature
    frequency: hourly
    transform:
      - daily_mean
  bias-correction: offset

- name: cooling_days
  units: days above 22C per month
  offset: -295.15   # absolute Kelvin minus 22 degrees
  cmip5:
    name: maximum_2m_temperature_in_the_last_24_hours
    frequency: daily
    transform: 
      - threshold_positive
      - monthly_count
  cmip6:
    name: daily_maximum_near_surface_air_temperature
    frequency: daily
    transform:
      - threshold_positive
      - monthly_count
  era5:
    name: 2m_temperature
    frequency: hourly
    transform:
      - daily_max
      - threshold_positive
      - monthly_count


- name: tropical_nights
  units: nights above 20C per month
  offset: -293.15   # absolute Kelvin minus 20 degrees
  cmip5:
    name: minimum_2m_temperature_in_the_last_24_hours
    frequency: daily
    transform: 
      - threshold_positive
      - monthly_count
  cmip6:
    name: daily_minimum_near_surface_air_temperature
    frequency: daily
    transform:
      - threshold_positive
      - monthly_count
  era5:
    name: 2m_temperature
    frequency: hourly
    transform:
      - daily_min
      - threshold_positive
      - monthly_count