Pausing HadISD updates in 2024

The HadISD dataset builds on NOAA NCEI's ISD dataset. There is work underway to replace the ISD with a new GHCNh (Global Historical Climate Network Hourly) product at NOAA, which will sit alongside the existing daily and monthly products under the GHCN brand.

As a result of this, when the ISD is no longer operationally updated, the HadISD will also cease to be updated.  Once this happens (likely at the end of this calendar year - the original notice from NOAA is already out of date) we will produce a final version of the HadISD and leave this available for some time on the home page.  A version will also be lodged at CEDA as usual.  This will allow any monitoring occurring on a calendar-year basis to happen on a complete dataset.

In due course we may look into the new GHCNh product to see whether we can build a "HadGHCNh" product from that.  Many of the quality control tests are similar in this new GHCNh and so we will need to do some careful investigation to ensure we are not erroneously keeping bad or removing good values if we apply the HadISD QC suite on top of these already QC'd data.

Next steps

Given the issues with the buddy check described in a previous post, we intend to release two versions in early 2024:  

• v331_202312p which follow on from other versions, with the buddy checks not being applied
• v340_2023f where we will reinstate the buddy checks.

Thereafter updates to HadISD will cease for the foreseeable future. 

 

We hope the approach of these two releases will give clarity and consistency to users of HadISD, and also enable us to perform some further investigations on the impacts of the inclusion of the buddy checks (and corrected unflagging steps) on the data at this point.  Users can also ensure they pick a dataset version which is consistent with any other approaches they have done. It also means that those who are using HadISD for climate monitoring can assess the calendar year 2023 and then have time to plan to use GHCNh.

 

As always, if you see anything untoward in the HadISD, do let us know!