RELEASE NOTES FOR CRU TS v4.07: 19 April 2023

The CRU TS dataset was developed and has been subsequently updated,
improved and maintained with support from a number of funders,
principally the UK's Natural Environment Research Council (NERC) and the
US Department of Energy. Long-term support is currently provided by the
UK National Centre for Atmospheric Science (NCAS), a NERC collaborative
centre. 

The 4.07 release of the CRU TS dataset covers the period 1901-2022.

The new interpolation algorithm is unchanged since v4.03.

To understand this dataset, it is important to understand its
construction and limitations. It is therefore recommended that all users
read the relevant paper:

Harris, I., Osborn, T.J., Jones, P. et al. Version 4 of the CRU TS
monthly high-resolution gridded multivariate climate dataset.
Sci Data 7, 109 (2020). https://doi.org/10.1038/s41597-020-0453-3


1. What's new in 4.07

1.1 Process changes

The underlying climatology for cloud cover (CLD) was recalculated
in 2022, along with climatologies for the other relevant variables,
released as CRU CL v1.1. However, later anaylsis, after feedback from
users,  revealed that, for CLD, the recalculation had produced an
inferior climatology. The CLD climatology has, then, been reverted to
v1.0 (the original). This affects all CLD data and, by implication, all
PET data. The comparison plots reflect this.

Work elsewhere in CRU has improved temperature and precipitation data
for Ascension Island and St Helena (https://crudata.uea.ac.uk/cru/data/ascension/),
this is reflected in the TMP and PRE datasets and can be seen in the
comparison plots.

1.2 Bug fixes

To the CLD climatology (see above).

2. Output files

For now, the approach of issuing NetCDF and ASCII files in parallel will
remain, as will the publications of decadal files as well as full-length
versions. However, decadal files may not be archived when superceded, in
order to make best use of space.


As always, please contact BADC in the first instance if you have any
questions, observations or suggestions (and have acquired CRU TS from
them). If, however, you wish to contact CRU directly about these datasets,
please contact me at i.harris@uea.ac.uk, as mail to other members of the
Unit will be passed through to me anyway.

Ian Harris
NCAS-Climate
Climatic Research Unit
School of Environmental Sciences
University of East Anglia
Norwich
NR4 7TJ

i.harris@uea.ac.uk