HadCRUT5 is a gridded dataset of global historical surface temperature anomalies relative to a 1961-1990 reference period. Data are available for each month from January 1850 onwards, on a 5 degree grid and as global and regional average time series. The dataset is a collaborative product of the Met Office Hadley Centre and the Climatic Research Unit at the University of East Anglia.
The current version of HadCRUT5 is HadCRUT.5.0.2.0, available from the download page.
— source: HadCRUT5 Index
A detailed description of the datasets can be found in the
Answers to Frequently Asked Questions.
List of the datafiles that are loaded by the Python script:
HadCRUT.5.0.2.0.analysis.summary_series.global.annual.ncHadCRUT.5.0.2.0.analysis.summary_series.northern_hemisphere.annual.ncHadCRUT.5.0.2.0.analysis.summary_series.southern_hemisphere.annual.nc
HadCRUT5 data are downloaded from: https://www.metoffice.gov.uk/hadobs/hadcrut5/data/HadCRUT.5.0.2.0/download.html
The following plots have been generated by the Python scripts hadcrut5_plot.py and hadcrut5_bars.py.
They require the Python libraries: Matplotlib, netCDF4, NumPy, and Requests.
If Python and the required libraries are not installed on your system, you can simply
install uv and run the commands listed below prefixed
with uv run. For example uv run ./hadcrut5_plot.py.
$ ./hadcrut5_plot.py --help
usage: hadcrut5_plot.py [-h] [-f OUTFILE] [-p PERIOD] [-m SMOOTHER] [-g] [-n] [-s] [-a ANNOTATE] [-v]
Parse and plot the HadCRUT5 temperature datasets v2024.1 (stable)
Copyright (C) 2020-2024 Davide Madrisan <[email protected]>
License: GNU General Public License v3.0
options:
-h, --help show this help message and exit
-a ANNOTATE, --annotate ANNOTATE
add temperature annotations (0: no annotations, 1 (default): bottom only, 2: all ones
-f OUTFILE, --outfile OUTFILE
name of the output PNG file
-g, --global plot the Global Temperatures
-m SMOOTHER, --smoother SMOOTHER
make the lines smoother by using N-year means
-n, --northern Northern Hemisphere Temperatures
-p PERIOD, --period PERIOD
show anomalies related to 1961-1990 (default), 1850-1900, or 1880-1920
-s, --southern Southern Hemisphere Temperatures
-t TIME_SERIES, --time-series TIME_SERIES
do plot the "annual" time series (default) or the "monthly" one
-v, --verbose make the operation more talkative
examples:
hadcrut5_plot.py
hadcrut5_plot.py --global --annotate=2
hadcrut5_plot.py --period "1850-1900"
hadcrut5_plot.py --period "1850-1900" --smoother 5
hadcrut5_plot.py --period "1880-1920" --outfile HadCRUT5-1880-1920.png
hadcrut5_plot.py --period "1880-1920" --time-series monthly --global
hadcrut5_plot.py select the period 1961-90 by default but supports (see the command-line switch--period) two other base periods found in the literature: 1850-1900, and 1880-1920.
$ ./hadcrut5_plot.py --annotate=2 --outfile plots/HadCRUT5-1961-1990.png
$ ./hadcrut5_plot.py --annotate=2 --period "1850-1900" --outfile plots/HadCRUT5-1850-1900.png
$ ./hadcrut5_plot.py --annotate=2 --period "1880-1920" --outfile plots/HadCRUT5-1880-1920.png
By adding the command-line option --smoother N you can create the same three plots, but using the N-year means data.
For instance --smoother 5 will get you a better idea of the trend lines.
Image generated for the anomalies related to the period 1880-1920.
$ ./hadcrut5_plot.py --period "1880-1920" --smoother 5 --outfile plots/HadCRUT5-1880-1920-smoother.png
The command-line option --time-series monthly selects the monthly HadCRUT5 datasets (by default the dataset providing the annual means is selected).
Image displying the monthly anomalies related to the period 1880-1920, for the global temperatures only.
$ ./hadcrut5_plot.py --global --period "1880-1920" --time-series monthly
usage: hadcrut5_bars.py [-h] [-f OUTFILE] [-p PERIOD] [-v]
Parse and plot the HadCRUT5 temperature datasets v2024.1 (stable)
Copyright (C) 2020-2024 Davide Madrisan <[email protected]>
License: GNU General Public License v3.0
options:
-h, --help show this help message and exit
-f OUTFILE, --outfile OUTFILE
name of the output PNG file
-p PERIOD, --period PERIOD
show anomalies related to 1961-1990 (default), 1850-1900, or 1880-1920
-v, --verbose make the operation more talkative
examples:
hadcrut5_bars.py
hadcrut5_bars.py --period "1850-1900"
hadcrut5_bars.py --period "1880-1920"
hadcrut5_bars.py --outfile HadCRUT5-global.png
The image for to the anomalies related to the period 1880-1920 follows.
$ ./hadcrut5_bars.py --period "1880-1920" --outfile plots/HadCRUT5-global-1880-1920.png
usage: hadcrut5_stripe.py [-h] [-f OUTFILE] [-r {global,northern,southern}] [-v] [-l]
Parse and plot a stripe image of the HadCRUT5 temperature datasets v2024.1 (stable)
Copyright (C) 2020-2024 Davide Madrisan <[email protected]>
License: GNU General Public License v3.0
options:
-h, --help show this help message and exit
-f OUTFILE, --outfile OUTFILE
name of the output PNG file
-r {global,northern,southern}, --region {global,northern,southern}
select between Global (default), Northern, or Southern Temperatures
-v, --verbose make the operation more talkative
-l, --no-labels do not disply the header and footer labels
examples:
hadcrut5_stripe.py
hadcrut5_stripe.py --no-labels --region northern
hadcrut5_stripe.py --region global --outfile HadCRUT5-stripe-global.png
Below is a generated striped image for global anomalies.
$ ./hadcrut5_stripe.py --region global
The Python code of this project is released under the GPL-3.0 license. The graphics have a CC-BY4.0 license, so can be used for any purpose as long as credit is given to Madrisan Davide and a link is provided to this website.