### Data Extraction

**NCEI NOMADS**and NCMP: reanalysis (CFSR,NARR,R1,R2); NWP (NAM, GFS, RUC); GENS ensembles, SST**NOAA PSL**Search and Plot. (R1,R2,20CR, NARR)**NOAA****IRI**(CFSR,20CR,R1,R2)**ECMWF**ERA-40, ERA-Interim (Get netCDF or GRIB files from the daily or subdaily data) **ECMWF**: ERA-20C**NASA**GES DISC Data Collections: MERRA**NCAR****,**Highest-resolution files for all reanalyses, except MERRA. GRIB parameter field extraction using cURL, and some conversion to netCDF as noted.**NASA**MERRA and MERRA2 Data Subsetter (variable list for MERRA-2)- OpenDAP servers: NOAA PSL (20CR,R1,R2,NARR), NCEP, MERRA2D, MERRA3D
- OpenDAP: MERRA Gridded Innovations and Observations (GIO)
**OpenGrADS.org**: GrADS software with additional user functionality, including GUI for reanalyses including NCEP and MERRA**Earth System Grid Federation**(CFSR, MERRA, 20CR, JRA-25, ERA-Interim) Obs4MIPS: Easy access to NetCDF reanalyses data of selected variables corresponding to the CMIP5 climate model output**GOAT: Geophysical Observations Analysis Tool****fo**r MATLAB

### Step-by-Step Guide to obtaining data files

- Step by step descriptions of how to get the data at the reanalyses centers are available.

### Post Processing Routines and Algorithms

### Webtools to plot/analyze data by Function

#### Basic Maps

**NOAA****IRI****(**CFSR,20CR,R1,R2)**NOAA PSL**Search and Plot (20CR,R1,R2,NARR)**NASA**MERRA: Uses Giovanni to produce maps or animations of some monthly fields. Can average over successive times.**NOAA**NOMADS (CFSR,NARR,R1,R2)**ECMWF**ERA-40, ERA-Interim (Plot maps) **NASA**MERRA Atlas**NOAA/PSL**Web-based Reanalysis Intercomparison Tool for maps makes user-selected reanalysis fields for monthly data. It can also difference two reanalyses or selected observational datasets with user-selected climatologies.- The Climate Reanalyzer makes user-selected reanalysis fields and differences for monthly data.
**MeteoCentre**provides pre-generated synoptic maps of SLP, 1000-500 thickness, and 500 hPa height (20CR and R1).**GOAT: Geophysical Observations Analysis Tool**for MATLAB

#### Other Basic Geographic Plots

**NOAA PSL**:Crossections**NOAA PSL**: Search and Plot**MERRA**: Uses Giovanni to produce hovmollers of some monthly fields.**The Royal Netherlands Meteorological Institute (KNMI) Climate Explorer****GOAT: Management and Analysis of Geophysical-Data Made Simple****f**or Matlab**Met Data Explorer**

#### Hovmollers

**NOAA/PSL**: Hovmollers (R1)**IRI****GOAT: Geophysical Observations Analysis Tool:**Management and Analysis of Geophysical-Data Made Simple for Matlab

**Advanced Plots**

- NOAA PSL: Can plot monthly, daily and sub-daily of crossections from composite plotting pages (R1). Anomalies are available.
- NOAA/PSL: Hovmollers of means, anomalies of daily data. Anomalies are available (R1).
- GOAT: Temporal and spatial subsettting is supported via a GUI or built in function. Built-in calculation of anomalies and climatology. Superimpose or show the difference between two fields. Display land-cover or topography.

#### Composite Maps (Average different, possibly non-contiguous dates together)

**NOAA PSL**: Can plot composite maps and vertical crossectons from composite plotting pages on monthly, daily and sub-daily time scales for R1. Anomalies are available.**NOAA PSL**: Can plot composite maps from plotting pages on monthly, daily and sub-daily timescales for 20CR. Anomalies are available. For monthly, plot composite maps of the 20CR ensemble spread (uncertainty).**GCOS****/****WGSP**: Can plot composite maps of sea level pressure from plotting pages on monthly timescales. Anomalies are available.**WRIT maps**: Can plot composite maps of a reanalysis or the difference of composites from two reanalyses.**GOAT:**Can plot composites of non-contiguous dates.

#### Correlation Maps

**NOAA PSL**WRIT Correlations**NOAA PSL**: From monthly NCEP/NCAR R1**KNMI****The Climate Reanalyzer**(ERA-Interim, NCEP/NCAR R1, NCEP/DOE R2, 20CR, observational datasets: PRISM precipitation, ERSSTv3b)

#### Timeseries Plots

**NOAA PSL**Plot simple timeseries of NCEP/NCAR R1 and 20thC Reanalysis monthly variables**IRI Data Library****Met Data Explorer****: Unidata****Web-based Reanalysis Intercomparison Tool for timeseries****(WRIT**) makes user-selected reanalysis timeseries, scatter plots, cross-correlation functions, and probability density functions for monthly data. It can also difference two reanalyses or selected observational datasets.**The Climate Reanalyzer**makes user-selected reanalysis time series with land/ocean masking.

#### Timeseries Analysis

**KNMI**: Plot, compute annual cycle, filter and other tools available for time series analysis. Provides many climate/ocean time-series.**NOAA/PSL**: Correlate and do some other simple analysis on pregenerated or user supplied monthly time-series**NOAA/PSL**: Extract daily timeseries from datasets. Can supply user criteria (e.g. top 10 temperatures in January for a point). R1,20CR**NOAA/PSL:**Extract monthly timeseries from datasets. R1,20CR**IRI Data Library****NOAA PSL:**Web-based Reanalysis Intercomparison Tool for timeseries (WRIT) makes user-selected reanalysis timeseries, scatter plots, cross-correlation functions, wavelets, and probability density functions for monthly data. It can also difference two reanalyses or selected observational datasets.

#### Google Earth

### Miscellaneous

**NOAA/PSL**Lead/Lag for Composites**NOAA\/PSL**Lead/Lag for Correlations (maps)**KNMI**Smoothed fields, EOF, SVD and other analysis**NOAA/PSL**WRIT Trajectory calculator (20CR, CFSR)

### Applications that read/plot/analyze netCDF and/or grib data (non-web)

A complete list is at Unidata

**NCL: NCAR Command Language****GrADS****:**The Grid Analysis and Display System (GrADS)**IDV****:**Integrated Data Viewer**Ferret****:**Data Visualization and Analysis: From NOAA/PMEL**NCO****:**NetCDF Operators. The NCO toolkit manipulates and analyzes data stored in netCDF-accessible formats, including DAP, HDF4, andHDF5. It exploits the geophysical expressivity of many CF (Climate & Forecast) metadata conventions, the flexible description of physical dimensions translated by UDUnits, the network transparency of OPeNDAP, the storage features (e.g., compression, chunking, groups) of HDF (the Hierarchical Data Format), and many powerful mathematical and statistical algorithms of GSL (the GNU Scientific Library). NCO is fast, powerful, and free.**CDO****:**Climate Data operators. A collection of command-line operators to manipulate and analyze climate and numerical weather prediction data; includes support for netCDF-3, netCDF-4 and GRIB1, GRIB2, and other formats.**MATLAB****IDL:**Interactive Data Language**CDAT Community Data Analysis Tools: CDAT****:**Note this will be replaced soon by xCDAT**xCDAT****:**xCDAT is an extension of xarray for climate data analysis on structured grids. It serves as a spiritual successor to the Community Data Analysis Tools (CDAT) library.**GOAT****:**Geophysical Observations Analysis Tool: A MATLAB based tool that integrates with NetCDF files and OPeNDAP sources.

### I don't have ERA code…

I don't have ERA code explicitly but there is this page

https://psl.noaa.gov/data/gridded_help/tools.html#idl

you can also check the MERRA2 webpages and email them with questions. I believe they have a helpdesk.

Cathy

### Help

Please can anyone help me? I failed install NCL on my window platform, i fallowed the instruction but could not start to work.

### How to download hourly data for radiation balance components

I really need help.

I want to download data for

-Incoming shortwave and outgoing shortwave radiation

-Incoming longwave and outgoing longwave radiation

-Albedo and net radiation.

Location: Lagos Nigeria

These data must be hourly with good resolution.

Please any help?

Thanks

### What is the time period of interest?

Dear Moses,

There are very few datasets that are hourly and extend over a long time period. Is there a specific time period that you are interested in?

best wishes,

### Reply: How to download hourly data for radiation balance compone

Moses,

A couple of points. MERRA, MERRA-2 and CSFR have 1 hourly data, others may too, you should review the characteristics of these and others to see which best suits your needs. When you say resolution must be good, do you mean spatial resolution? And if so, what is good resolution?

Keep in mind that when using reanalysis data, the radiation parameters are strongly dependent on *modeled* cloud fields. This can lead to significant uncertainty in the values.

Once you figure out which you want, then you can start looking to see if they have tools that permit the download of point data (MERRA/MERRA-2 both do). Their documentation is listed here.

### hourly data

For there ERA5

https://www.ecmwf.int/en/newsletter/147/news/era5-reanalysis-production

For CFSR

https://www.ncdc.noaa.gov/data-access/model-data/model-datasets/climate-forecast-system-version2-cfsv2#CFS%20Reanalysis%20(CFSR)

The 20CRV2c has 3 hourly data for surface fluxes. The MERRA and ERA have higher spatial resolution.

As the others asked, what time period?

### Hi, …

Hi,

Need to plot streamlines using ECMWF winds (U and V) over Asian region ...Can I have matlab code?

### Suggest a matlab users group

Dear Andy,

I suggest also trying a matlab user group for plotting tools specific to matlab.

best wishes,

### streamlines and matlab

While I don't think matlab has an email list, they do have extensive help pages. I searched and see

https://plot.ly/matlab/streamline-plots/

https://www.mathworks.com/help/matlab/ref/streamline.html

https://www.mathworks.com/help/matlab/ref/stream2.html

They also have libraries to read netCDF files.

Cathy S.

### Re: Need to plot zonal means of meridinal winds-stream functions

### Re: Need to plot zonal means of meridinal winds-stream functions

### 20CR - pr_wtr vs prate variables

I'd like to access from 20CR (ver 2c) daily rainfall for a specific lat/lon reference point. Is there a relationship between the daily pr_wtr output variable and the monthly mean prate variable? Is it valid to compare actual daily rainfall with data derived from pr_wtr?

### Re: 20CR - pr_wtr vs prate variables

### Problems with incoming shortwave from ERA-I

### Re: Problems with incoming shortwave from ERA-I

### Re: Problems with incoming shortwave from ERA-I

### Re: Problems with incoming shortwave from ERA-I

Please ignore this question since I found my error. The error had to do with the way I was downloading the data, which was not including the entire day. Thanks anyways,

Sebastian

### Re: How to read the SAGE II V7 file with Matlab

### Re: How to read the SAGE II V7 file with Matlab

### Re: How to read the SAGE II V7 file with Matlab

### add_offset and scale factor in ERA-I

### Re: add_offset and scale factor in ERA-I

### Re: add_offset and scale factor in ERA-I

### Re: add_offset and scale factor in ERA-I

### Re: add_offset and scale factor in ERA-I

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

Hi subramanyam , In order to help, anyone looking at this would need to have a link to the data you are trying to open. Grads and opengrads are similar in their capacity to open files. You may prefer to search the grads forum, then ask this question if it hasn't already been discussed. I did a quick google search and found:

http://gradsusr.org/pipermail/gradsusr/2012-December/033787.html

Good Luck

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Any hourly mean sea level pressure data

### Re: Any hourly mean sea level pressure data

### Problem with longitude in 20CR data

### Re: Problem with longitude in 20CR data

### Re: How to obtain/plot/analyze data

### How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to read GFS SFC data files

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: ASCII timeseries of daily surface parameters from CFSR

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

Stefan,

Adding panoply is a great idea, but Reanalyses.org is a wiki site that depends on users. You can login and add it where you feel it is appropriate. If you have any questions, please feel free to ask or add a question to the Help section.

best wishes,

gil compo

### Re: How to obtain/plot/analyze data

### Re: How to obtain/plot/analyze data

This page needs more work. What do users find useful here?

## open and read ERA5 grid data inside IDL

Dear Sir,

I would like to open ERA5 grid data that was downloaded from ECMWF.

Could you please send me some code to open and read with a visualize such kind of data.

I wait your reply as soon as possible.

Best wishes

Khaled