Contrail forecast data

This document species the NetCDF data contract for contrail forecast data as returned by the Contrail Forecast API method getGrids.

Data format

Forecast grids cover the whole globe and are returned in the netCDF4 format.

Dimensions

Name Type Description
longitude float32 -180 to +180 (inclusive), as configured in the request. Grid resolution is 0.25 degrees but may change in the future.
latitude float32 -90 to +90 (inclusive), as configured in the request. Grid resolution is 0.25 degrees but may change in the future.
flight_level int16 [270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440], as configured in the request, in hectofeet. Flight levels are derived from pressure levels.
time datetime64[ns] The requested real world forecast date and time, in UTC.
forecast_reference_time datetime64[ns] Date and time at which the forecast was computed, rather than the time of forecast itself, in UTC.

Variables

contrails (float32): (longitude, latitude, flight_level, time) continuous contrail forcing index values from [0 - 4].

Contrail forcing index values are inspired by turbulence forecast values.
Severity values can be interpreted as:
Value Interpretation
0 None
1 Low (light)
2 Moderate
3 High (severe)
4 Extreme

Example

Example scaling translates ef_per_m to contrails index: 
ds["contrails"] = ds["ef_per_m"].clip(min=1e7, max=2e9)
ds["contrails"] = ((ds["contrails"] - 1e7) / (2e9 - 1e7)) * 4
 For more information on background informing example mapping from ef_per_m to contrails index, see Energy Forcing Interpretation.

References