# Report a data access error in ERA5 single-level dataset

**URL:** <https://forum.ecmwf.int/t/report-a-data-access-error-in-era5-single-level-dataset/1169>\
**Category:** C3S - Access and Login\
**Tags:** access, c3s, era5\
**Created:** [22 November 2023 09:53 UTC](https://forum.ecmwf.int/t/report-a-data-access-error-in-era5-single-level-dataset/1169 "2023-11-22T09:53:40Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Qi\_Zhang](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/q/bc79bd/32.png) [@Qi\_Zhang](https://forum.ecmwf.int/u/Qi_Zhang)\
**Post date:** [22 November 2023 09:53 UTC](https://forum.ecmwf.int/t/report-a-data-access-error-in-era5-single-level-dataset/1169/1 "2023-11-22T09:53:40Z")

</div>

Problem description: I downloaded three netcdf data files (each file contains swh and wind speed) around three regions in the same time range. The three regions are quite similar in space with merely 1.5 degree difference at most&nbsp; in longitude or latitude range. I picked and compared data points of the same time and location from three files. Below is a example, I picked a same data point (significant wave height, 2020-01-01 02:00:00, 119°E 25°N) of three files to state the problem. As you can see, they are totally different, and a pattern appears, where longitude columns in second file are consistent with the first file with one column difference ( for example, please compare '119' column in the first file with ' 118.75' column in the second ).

Does it mean there exists some data access problem?

 ![](https://forum.ecmwf.int/uploads/default/original/1X/5c5ebd91f013774537734dd2e46f84ab8fd9a8d1.png)

fig. 1 the first data file

 ![](https://forum.ecmwf.int/uploads/default/original/1X/2ce04073314cf496050854fc27ef884ba213f345.png)

fig. 2 the second data file

 ![](https://forum.ecmwf.int/uploads/default/original/1X/c20b3ccae88a9492ff8fa1af78db3ce20ec834e8.png)

fig. 3 the third data file

---

<div class="post-metadata">

**Author:** ![Qi\_Zhang](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/q/bc79bd/32.png) [@Qi\_Zhang](https://forum.ecmwf.int/u/Qi_Zhang)\
**Post date:** [29 November 2023 01:09 UTC](https://forum.ecmwf.int/t/report-a-data-access-error-in-era5-single-level-dataset/1169/2 "2023-11-29T01:09:33Z")

</div>

This [link](https://prod.ecmwf-forum-prod.compute.cci2.ecmwf.int/t/era5-requests-for-atmospheric-and-wave-variables-in-netcdf/1628) definitely explains the problem.