# CDS quota increase request - 5.5 TB CERRA retrieval for European/Turkey hail modeling research (deadline)

**URL:** <https://forum.ecmwf.int/t/cds-quota-increase-request-5-5-tb-cerra-retrieval-for-european-turkey-hail-modeling-research-deadline/14874>\
**Category:** C3S - Datasets and Usage\
**Tags:** cerra\
**Created:** [19 April 2026 08:33 UTC](https://forum.ecmwf.int/t/cds-quota-increase-request-5-5-tb-cerra-retrieval-for-european-turkey-hail-modeling-research-deadline/14874 "2026-04-19T08:33:12Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![guven\_fidan](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/g/ac8455/32.png) [@guven\_fidan](https://forum.ecmwf.int/u/guven_fidan)\
**Post date:** [19 April 2026 08:33 UTC](https://forum.ecmwf.int/t/cds-quota-increase-request-5-5-tb-cerra-retrieval-for-european-turkey-hail-modeling-research-deadline/14874/1 "2026-04-19T08:33:12Z")

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Hello ECMWF / C3S team,

I am a researcher at Özyeğin University (Istanbul, Turkey) working on  
a **hail event modeling study** covering European and Turkish domains.  
The project requires the full **CERRA reanalysis** (single-levels and  
pressure-levels) over 20 years (2005–2024), totaling **~7.7 TB**.  
Due to a project submission deadline on **Wednesday, 2026-04-22** ,  
I am requesting your support for completing this retrieval in time.

## Research context

- University: Özyeğin University
- Purpose: Historical hail event analysis and atmospheric modeling  
(surface variables + pressure-level profiles) for Europe and Turkey
- Non-commercial, academic research

## Current setup

- Account email: `guven.fidan@ozu.edu.tr`
- Using `cdsapi` with monthly-split requests  
(each variable × each month, 96 requests/year)
- Running 7 parallel script instances on different years, 4–6 workers each
- Observed per-script throughput: ~7.6 GB/hour
- Combined aggregate throughput: ~25–30 GB/hour

## Progress so far (~1.54 TB completed)

- Completed: 2020, 2022, 2023, 2024
- In progress: 2013–2019 (except 2020) via CDS
- Remaining: ~3.5 TB

## Issue

At the current aggregate rate, the remaining ~3.5 TB will take ~120 hours  
— which misses the Wednesday deadline by a significant margin.

## Questions

1. Is it possible to **temporarily increase my queue / concurrent  
request limit** for the next 4 days to expedite this academic retrieval?
2. Is there any **bulk/institutional download path** for multi-TB  
CERRA research campaigns (e.g., MARS direct access, alternative endpoint)?
3. Any guidance on request structure to accelerate tape-archive retrieval?

I have already attempted WEkEO HDA as a parallel path, but per-connection  
throughput is ~0.2 MB/s (server-throttled), so only CDS is viable.

Thank you very much for any assistance you can provide for this  
time-sensitive research work.

Best regards,  
Güven Fidan  
Özyeğin University