# Questions on downloading and processing ERA5 temperature tendencies

**URL:** <https://forum.ecmwf.int/t/questions-on-downloading-and-processing-era5-temperature-tendencies/1582>\
**Category:** C3S - Datasets and Usage\
**Tags:** access, c3s, era5\
**Created:** [4 July 2023 12:17 UTC](https://forum.ecmwf.int/t/questions-on-downloading-and-processing-era5-temperature-tendencies/1582 "2023-07-04T12:17:02Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Bo\_Liu](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/b/4af34b/32.png) [@Bo\_Liu](https://forum.ecmwf.int/u/Bo_Liu)\
**Post date:** [4 July 2023 12:17 UTC](https://forum.ecmwf.int/t/questions-on-downloading-and-processing-era5-temperature-tendencies/1582/1 "2023-07-04T12:17:02Z")

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**Questions on downloading and processing ERA5 temperature tendencies**

Hi there!

The summary of my question is as follows. Overall, there are three questions.

**Q1. The speed of processing and downloading temperature tendencies is too slow.**

I have downloaded the temperature tendencies in ERA5 with the horizontal resolution of 0.75 degrees for December-to-February for the period 1979-2022. Every time I download a tendency file containing one time step because the code provided ‘conversion\_from\_ml\_to\_pl.py’ could only deal with tendency files with one time step [see Q2 for details]. So I am wondering if there is any way to increase the processing and downloading speed of temperature tendencies?

**Q2. The problem with the code ‘conversion\_from\_ml\_to\_pl.py’.**

As mentioned above, only one time step file could be successfully converted from model level to pressure level. Once there are files with two or more time steps, I got the following errors like,

Not all required lnsp dimensions found -exiting&nbsp; ('time', 'step', 'latitude', 'longitude')

Not all required variable dimensions found -exiting&nbsp; ('time', 'step', 'hybrid', 'latitude', 'longitude')

Not all required variable dimensions found -exiting&nbsp; ('time', 'step', 'hybrid', 'latitude', 'longitude')

Not all required variable dimensions found -exiting&nbsp; ('time', 'step', 'hybrid', 'latitude', 'longitude')

Not all required variable dimensions found -exiting&nbsp; ('time', 'step', 'hybrid', 'latitude', 'longitude').

So I am wondering if you could help me to solve this question.

**Q3. Which method is more suitable to interpolate the 0.75 degrees data to 1.5 degrees?**

The relatively high horizontal resolution of 0.75 degrees makes our next calculation more time consuming. So we want to use a relatively low resolution of 1.5 degrees instead. However, as mentioned above, downloading temperature tendencies in ERA5 is much more time-consuming than downloading other common variables. So I am here to ask what kind of interpolation method is more suitable to interpolate the data from 0.75 degrees to 1.5 degrees.

Looking forward to any reply!

Best,

Bo Liu