How do i use datasets from ecmwf?

Hi,

I want to learn more about matlab so i reached out one of my professors. And he told me we can make a comperason with data from "ecmwf" and his own measurement.

I cannot contact my proffessor atm. and i have a lot of free time between semesters. Can andbody guide me on how can i plot these files?

Not even sure if these files are coorect so here is the link to the ecmwf open database.

Answer 1

[Karanjot]

Hi Emmeirrt,

First of all, Since you are new to MATLAB, I recommend exploring MathWorks' Self-Paced Courses. For instance, to get started with the MATLAB language and environment, Consider completing the MATLAB Onramp:

https://matlabacademy.mathworks.com/details/matlab-onramp/gettingstarted

Now, The ecmwf data seems to have files in the GRIB and INDEX format. To import GRIB Files into MATLAB, You may use NetCDF/GRIB reader from File Exchange or NCTOOLBOX. These offer a collection of functions to read GRIB and netCDF files.

Here is an example using NCTOOLBOX:

%Sample data obtained from ftp://polar.ncep.noaa.gov/pub/history/waves/multi_1.at_4m.dp.200607.grb2
% create ncgeodataset object
nc=ncgeodataset('multi_1.at_4m.dp.200607.grb2');

% list variables
nc.variables

% create geovariable object
dirvar=nc.geovariable('Primary_wave_direction_degree_true_surface');

% get data at 1st time step
dir=dirvar.data(1,:,:);

% get grid at 1st time step
g=dirvar.grid_interop(1,:,:);

% plot
pcolorjw(g.lon,g.lat,dir);
title(datestr(g.time))

I hope this helps!