ECMWF Open Data download and conversion functions

[swarnaleem]

trafficstars

ECMWF Open Data 15-day forecast download and conversion to NetCDF (from Grib2)

Description

The download.ECMWF.R function downloads ECMWF Opendata 15-day perturbed forecast (pf) consisting of 50 ensemble members using ecmwf-opendata python package. Currently, it is downloading 50 ensemble members using download_ecmwf_opendata.py. The parameters being downloaded are as follows:

Parameter Short Name	Name
2t	2 metre temperature
tp	total precipitation
10u	10 metre U wind component
10v	10 metre V wind component
q	Specific humidity
r	Relative humidity
sp	Surface pressure

After downloading, ecmwf_grib2nc.py function converts the grib2 file consisting of 50 ensemble members into 50 separate netCDF files based on their ensemble numbers.

Motivation and Context

PEcAn currently has 17 meteorological drivers available, some of which are Ameriflux, ERA5, and CMIP5 which are used as input data to various models. ECMWF Open Data provides globally available ensemble forecasts that can be used to drive various models (available in PEcAn).

Creating an ECMWF Open Data pipeline in PEcAn would help in adding various meteorological forecast data (weather data) as input variables to the ecosystem models which would help in running them in the future. In this proposal, the interest is around 15-day ensemble forecast that originates from the day of the forecast and goes 360h into the future.

Review Time Estimate

• [ ] Immediately
• [x] Within one week
• [ ] When possible

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My change requires a change to the documentation.
• [ ] My name is in the list of CITATION.cff
• [ ] I have updated the CHANGELOG.md.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [ ] All new and existing tests passed.

[mdietze]

@swarnalee-m we'd love to pull in this code. Any chance you can address the few remaining issues?

[mdietze]

@swarnalee-m pinging you again to hopefully finish up this PR

[mdietze]

@istfer any chance you can finish up this PR? @swarnaleem hasn't touched it in a year and doesn't seem to be responding to inquiries about addressing the changes you requested.

[istfer]

I can give it a try