Friday 16 September 2016

HadISD version 2.0.0.2015p

We submitted the HadISD version 2 paper to Climate of the Past in September 2015, with the dataset tentatively versioned as v2.0.0.2014p.  It went through the review process with a number of helpful comments being given by the two referees.  

Some of these comments were addressed to the way the stations were selected and to add more stringent tests during this part of our code.  We adjusted our code in light of these comments, but as we were then about to perform our standard update on HadISD version 1 (to 1.0.4.2015p), we waited until we were able to include data from 2015 into an updated version 2 as well before re-running our station selection code.

Another of the comments was that the paper would be best suited to a different journal, and a sister journal of Climate of the Past - Geoscientific Instrumentation, Methods and Data Systems (GI) - was suggested.

We re-ran the updated station selection code, all the quality control procedures, homogeneity assessment and comparison to HadISD.1.0.4.2015p to create HadISD.2.0.0.2015p.  We submitted our updated manuscript to GI on 17th March 2016.  

After a long time in discussions with the editorial team to explain why the manuscript was very similar to our Climate of the Past Discussion paper, the paper was published in GID on 12th September 2016.  The editorial team have decided that as this manuscript has already gone through one round of open peer review in an EGU journal, the discussion phase could be closed before the usual period had completed, on 13th September.  We are now in the process of submitting our final files to GI.

We have released HadISD.2.0.0.2015p on the HadOBS server at www.metoffice.gov.uk/hadobs/hadisd.  We expected further comments from review process at GI, and had intended to update the dataset in light of these, creating v2.0.0.2015f.  However this will now not happen, and the first release of HadISD2 will remain at v2.0.0.2015p.  We intend to perform annual updates on HadISD2 on similar timescales as for HadISD, and so expect the next update to be in January 2017 to create v2.0.1.2016p.

Please read the papers on HadISD version 2 before using this dataset and also get in touch if you have any concerns with the data so we can check and address them if necessary.

The major changes when going to version 2 from version 1 is the increase in the timespan covered by the dataset, back to 1931.  We have also refreshed the station selection criteria, and there are 7677 unique station IDs present in this version; but this will change on each new release.  A number of the QC tests have had minor tweaks, and we have also improved the level of QC applied to wind speed and direction observations.

Update - 29/09/2016

The paper describing HadISD.2.0.0.2015p has been published in Geoscientific Instrumentation, Methods and Data Systems.   As stated above, the data are available on the HadOBS server.

Monday 1 August 2016

HadISD available at CEDA/BADC with updated licence

We have been working with the British Atmospheric Data Centre (BADC) over the past year or so to make some of the datasets currently available on the HadOBS website also available through the BADC Centre for Environmental Data Analysis (CEDA) data archive as part of the CLIPC project.

HadISD v1.0.3.2014f and v1.0.4.2015p are now available through that portal.  Not all the facets available in the netCDF files hosted by HadOBS are included in these data, but the climate variables and quality information are present.

We intend that CEDA becomes an alternate route for users to access our data and also be able use some of their download tools (e.g. via OpenDAP).

As part of this process we have updated the licence under which HadISD is released.  This also ensures that the data comply with the licence issued by NOAA/NCEI on the ISD dataset.  The new licence is as follows:

"HadISD is distributed under the Non Commercial Government Licence. The data are available for non-commercial use with attribution to the data providers. Please cite Dunn et al (2012). This product may contain data which are governed by WMO Policy following WMO Resolution 40 Annex 1 alongside additional data that may have restrictions placed on their commercial use by the data owners. Any redistribution of this product should be accompanied by a similar statement of usage policy."

Any users who have concerns about what HadISD can be used for are encouraged to get in touch to discuss their project.  

Friday 22 July 2016

HadISD 1.0.4.2015f

We have just released HadISD version 1.0.4.2015f.  All plots and files should be on the website. This version  supersedes the preliminary version from earlier this year (v1.0.4.2015p).  There have been further updates to the ISD source data for the years 2007-10, 2012-13 and 2015 since the preliminary dataset was created in January, but no changes in other years. 

The raw data were downloaded on 17th June 2016, and processed over the last month  We have made no substantial changes to the codes which do the conversion to NetCDF files or the Quality Control suite, and so there is only the update in the version number is from preliminary to final.  

This version still contains 6103 stations, with 4050 passing the final filtering checks, down slightly from the 4060 in v1.0.3.2014f (see the HadISD paper Section 6).  The patterns of flagging are very similar to v1.0.3.2014f.  However if you find something strange, do let us know using the contact details on the HadISD website.  Please note the stations which are known to have issues are documented on this blog and on the website.



Fig.1 The fraction of all temperature records flagged for each station

Fig. 2 The fraction of all dewpoint temperature records flagged for each station


Fig. 3 The fraction of all sea-level pressure records flagged for each station






The Homogeneity information for this version is also available on the website using the same procedure (PHA) as outlined in Dunn et al, 2014.

As always, if you see anything untoward in the data or are having problems using it, please do not hesitate to get in touch.

Licencing

The licence under which HadISD is released has been changed to a Non Commercial Government Licence.  Full details are on the HadISD websitePlease ensure you read and follow the terms of this licence before using the data.

Monday 25 January 2016

HadISD.1.0.4.2015p

We have just released HadISD version 1.0.4.2015p.  All plots and files should be on the website This update extends the coverage of the dataset to the end of 2015 (31 December at 2300 inclusive).  It remains a preliminary dataset as there could still be further updates to the ISD dataset in the next few months.  We hope to do a processing run for the final version some time around Easter (to create 1.0.4.2015f). 

The raw data were downloaded on 7th January 2015, and processed over the subsequent days.  There have been changes to all of the raw files in 2012-2014 as part of the normal ISD update process  We have made no substantial changes to the codes which do the conversion to NetCDF files or the Quality Control suite.  Hence the version number has only incremented by 0.0.1 and the year.  Any updates to these systems will be included in the future HadISD.2.0.0. 

This version still contains 6103 stations, with 4049 passing the final filtering checks, down slightly from the 4060 in v1.0.3.2014f (see the HadISD paper Section 6).  The patterns of flagging are very similar to v1.0.3.2014f.  However if you find something strange, do let us know using the contact details on the HadISD website.  Please note the stations which are known to have issues are documented on this blog and on the website.



Fig. 1 The fraction of all temperature records flagged for each station

Fig. 2 The fraction of all dewpoint temperature records flagged for each station
Fig. 3 The fraction of all sea-level pressure records flagged for each station

The Homogeneity information for this version is also available on the website using the same procedure (PHA) as outlined in Dunn et al, 2014.

As always, if you see anything untoward in the data or are having problems using it, please do not hesitate to get in touch.