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2/28/2019 9:01 pm  #11

Re: Reanalysis Grib

This link that Campbell provided works quite well for ECMWF...  The registration process was nice and quick and only a valid email was required to be provided and then verified and password setup.  Thank you Campbell!



3/11/2019 1:41 pm  #12

Re: Reanalysis Grib

Also check out the UERRA project for some high-res (regional) European reanalysis models.

On a related note: Have you guys developed an efficient workflow once you have gotten hold of the data?

For example, how would I run routings starting a few hours around noon every day, for 10 days before and after day X (raceday), for the past 15 years? The staggered start times in 'multiple' require evenly spaced gaps, right? So it's either hourly, daily, or yearly routes, but no combination of these whilst skipping the winters.

As a workaround I've been playing with the idea of changing the timestamps on the GRIBs so they would all 'look' like a single year, but that seems even more tedious then just clicking the button a 100 times and watching the paint dry.

In a perfect world, I'd run this for various polars (eg sail suits / boat modes), with a single click on some kind of 'batch-routing'-feature. Is there some hidden possibility there, or should this move to feature requests?

Last edited by jvr (3/11/2019 1:41 pm)


3/11/2019 4:14 pm  #13

Re: Reanalysis Grib

You have a link you can share that gets us to this?

"Also check out the UERRA project for some high-res (regional) European reanalysis models."


3/11/2019 11:52 pm  #14

Re: Reanalysis Grib

From the project website: http://www.uerra.eu/outreach/data-and-products/data-sets.html
Most models can be downloaded through the ECMWF website (or through a Python script), some also directly from the web. Lots of detail and comparison of model features in the pdf-reports on their site, too.


3/13/2019 3:55 am  #15

Re: Reanalysis Grib

the script works really well.


12/03/2019 6:52 am  #16

Re: Reanalysis Grib

from climate.copernicus.eu climate-reanalysis:
Preliminary data for ERA5 will be published daily, within seven days from real-time, and stored in a separate dataset (ERA5T). This service will be available later in 2019.

^^^ it's now 'later in 2019', and as promised preliminary data for the latest European Reanalysis is now available with only a 5 day lag (previously the wait was 3 months). Christmas has come early!



12/12/2019 7:20 am  #17

Re: Reanalysis Grib

Downloading the ERA-Interim files through the web interface seems to be possible just for single months. Here you can enter also an area. To download the grib files of several months you'd have to start many single requests which is really time consuming.

On the now new ERA5 with the web interface it is possible to download any combination of years/ months / days / times. But through the web interface it is not possible to select a specific area. Therefore always the grib file for the whole globe will be downloaded which leads to uneccessary large download files.
With the  toolbox request (either auto generated or modified from the tutorials) it seems to be possible to get only a .nc (NetCFD) file, not a grib file...

Is anybody of the smart Python users here willing to share his knowledge how to download the data (in grib format) with the python code? In step-by-step way for dummies.
I know how the request code would have to look like (copy paste from the toolbox), but I just don't know how get started in Python.



12/12/2019 8:10 am  #18

Re: Reanalysis Grib

There are some pretty clear instructions on getting started with the cdsapi here: https://cds.climate.copernicus.eu/api-how-to

You need to register for an api key (and put it in a configuration file that can be found by the module), install the cdsapi module, and then you can write scripts to download whatever you want. Below I've pasted in a script I wrote to download gribs for some post-race analysis on this year's Azores and Back Race (apologies, I'm not sure how to paste it in without the formatting getting mangled, but I'm sure you can sort that aspect out...there are also lots of example scripts on the Copernicus site). If you have any specific problems do ask and I'll help if I can.


import cdsapi 
c = cdsapi.Client() 
c.retrieve(    'reanalysis-era5-single-levels',    {        'product_type':'reanalysis',        'variable':[            '10m_u_component_of_wind','10m_v_component_of_wind','mean_sea_level_pressure'        ],        'year': '2019',        'month':'06',        'day':[            '18','19','20',            '21','22','23',            '24','25','26',            '27','28','29',            '30','31'        ],        'area': [51, -26, 37, -4],        'time':[            '00:00','01:00','02:00',            '03:00','04:00','05:00',            '06:00','07:00','08:00',            '09:00','10:00','11:00',            '12:00','13:00','14:00',            '15:00','16:00','17:00',            '18:00','19:00','20:00',            '21:00','22:00','23:00'        ],        'format':'grib'    },    'azab_2_wind_pressure.grib')


12/12/2019 8:13 am  #19

Re: Reanalysis Grib

you also need to install python on your pc, if it isn't already there

Last edited by us7070 (12/12/2019 8:13 am)


1/29/2022 6:57 am  #20

Re: Reanalysis Grib

Is there a similar dataset available for the Newport Bermuda race?  Surely someone has it.  I second the "very few seem to know how" comment.  I went to the cds.climate.copernicus.eu website and got the ERA5 hourly data but can't figure out how to get Expedition to read the downloaded .grib file.


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