Experts Warn Multiple Months Have Already Exceeded 1.5°C of Global Warming

A portrait of woman in front of fan suffering from heat. Hot weather concept

A new analysis of the world-leading HadCRUT5 global temperature record reveals that a total of six months, including March 2023, have exceeded 1.5°C of global warming, the threshold associated with the United Nations Framework Convention on Climate Change (UN-FCCC) 2015 Paris Agreement.

The analysis, conducted by EarthSystemData UK, assessed HadCRUT5 – a leading global data set used by the United Nations to monitor global climate, by re-expressing the data relative to its 1850-1900 pre-industrial average – in line with how the United Nations 1.5°C threshold is determined.

The months which have exceed 1.5°C of warming are: January 2016 [+1.51°C], February 2016 [+1.63°C], March 2016 [+1.62°C]; February 2020 [+1.53°C], March 2020 [+1.53°C]; and March 2023 [+1.56°C].  These findings reveal the first extended periods during which the globe has exceeded the established UN-FCCC ‘safe warming limit’, however they do not signify a formal breach of the legally-binding Paris Agreement target, which requires a multi-year average in excess of +1.5°C to confidently attribute the breach to human-causes.

“Nevertheless, we are seeing the first data points that will likely constitute that extended breach. There could be no clearer warning – as if repeated climate disasters are not enough, it is there now, in the numbers, right in front of us.” commented Dr. Craig Wallace who performed the analysis.

“2016, and to an extent, 2020, were influenced by strong EL Niño conditions which raise the planet’s temperature adding to the human carbon-driven warming. March 2023’s figure is exceptional, however, since it occurred during the tail end of a La Niña phase which actually cools the planet, offsetting some of the human, warming. This suggests the true human-driven heating in March was actually greater than the reported +1.56°C”

To learn more, visit

Dr. Craig Wallace performed the data analysis and is Lead Climate Scientist at EarthSystemData UK.

He holds a PhD in physical climatology from the Climatic Research Unit, University of East Anglia, UK. In addition to conducting climate analysis for EarthSystemData he has completed IPCC-cited research and has been a Senior Research Scientist on over 12 E.U. and U.K.-funded climate research projects.

Source data:

HadCRUT5 global observed temperature record [U.E.A./C.R.U. & UK METEOROLOGICAL OFFICE, UNITED KINGDOM]

Data set publication: Morice, C. P., Kennedy, J. J., Rayner, N. A., Winn, J. P., Hogan, E., Killick, R. E., et al. (2021).  Journal of Geophysical Research: Atmospheres, 126, e2019JD032361.

HadCRUT5 is a de-facto blended sea-surface and land-air temperature record used by scientists and global organisations  to detect and attribute global temperature change. It is paramount to the periodic UN Intergovernmental Panel on Climate Change (IPCC) assessment reports which inform global policy addressing climate change.

EarthSystemData Ltd
EarthSystemData is a United Kingdom climate data analytics and research firm, conducting analyses for private and public-sector organisations to help address and combat climate-impact risk.


Charts of the 1.5°C temperature exceedances are provided and may be reproduced under condition of attribution to EarthSystemData, UK 2023.

Image explanation:
Bar charts are of monthly-mean global temperatures for January, February and March, the three months in which mean temperatures have exceeded +1.5°C (dotted line) since the global record commenced in 1850.

Values are expressed as anomalies of each month’s 1850-1900 average – a period established by the UN IPCC as the pre-industrial era, against which current warming, and UN warming limits are benchmarked.