Global Daily Temperature Anomaly vs 1991–2020 (ERA5) · °C

## What this measures

How much warmer or cooler the globe was on each day than the 1991–2020 average for the same calendar day, in degrees Celsius, as Copernicus computes it. ERA5 is the European Centre for Medium-Range Weather Forecasts' reanalysis: a weather model run over the past, constrained by billions of observations, giving a complete global grid every hour since 1940. Copernicus averages the hourly 2-metre air temperature over the whole globe for each UTC day. 1 January 1940 to 17 October 2026.

## Why it matters

Taking out the seasonal cycle shows the warming itself, day by day, and how El Niño and La Niña push it around.

## How to read it

Above zero is warmer than the 1991–2020 normal for that date. The largest anomaly in this record is 1.16 °C on 17 November 2023; the latest, 17 October 2026, is 0.89 °C. The 1991–2020 normal is itself warmer than pre-industrial times, so these anomalies are smaller than the warming since 1850–1900 that the Paris Agreement targets refer to.

## What it does not say

The newest days are preliminary (built from ERA5T before the final ERA5 run) and are replaced, usually by a few hundredths of a degree, about three days later; Palanor rewrites the last 60 days on every run. A single day is weather; read the trailing 365-day mean (climate.era5.t2m_anomaly_365d_c) for the trend.

## Source

Copernicus Climate Change Service (C3S) / ECMWF, Climate Pulse, ERA5 daily global series: https://pulse.climate.copernicus.eu (file https://sites.ecmwf.int/data/climatepulse/data/series/era5_daily_series_2t_global.csv). Generated using Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains. Licence to Use Copernicus Products (version 1.2), §4.2: "Access to Copernicus Products is given for any purpose in so far as it is lawful". Read daily by /api/cron/climate-pulse-sync.