Monthly Warming Stripes

Microclimatev01.00 credits/fixed

Responsible:Niccolò Calandri

Monthly Warming Stripes

Overview

This chart shows the monthly temperature variations relative to the 1961–1990 baseline for the last 5 years. Each row represents one year, with 12 months on the horizontal axis. The position on the Z axis (vertical) and the colour indicate temperature anomalies:

Blue: temperature below the baseline (cooler than the 1961–1990 average)
Yellow: temperature close to the baseline (neutral)
Red: temperature above the baseline (warmer than the 1961–1990 average)

This visualisation helps to identify long-term warming trends and seasonal temperature patterns, allowing users to see in which month warming is most pronounced and how the thermal pattern changes month by month over the last few years.

Calculation Methodology

The calculation is based on Open-Meteo Historical Weather data (ERA5-Land reanalysis, ~10 km, 1940–present):

Extract the monthly mean temperature for each month of the last 5 years
Calculate the monthly reference mean for the period 1961–1990 (WMO baseline)
Calculate the monthly anomaly = temperature month X year Y − historical mean month X (1961–1990)
3D visualisation: X axis = months (Jan–Dec), Y axis = years (last 5), Z axis and colour = anomaly (°C)

Colouring:

Anomaly	Colour
< 0 °C (cooler)	Blue
≈ 0 °C (near average)	Yellow
> 0 °C (warmer)	Red

Unit: degrees Celsius (°C, anomaly relative to the 1961–1990 baseline)

Data Sources

Code	Name	Provider	Resolution	Availability
`WRD_OPNMT_99`	Open-Meteo Historical Weather	Open-Meteo (ERA5-Land)	~10 km	1940 — present

Quality Range and Levels

This KPI is a 3D visualisation of monthly thermal anomalies and does not include an A–E quality level classification. It is an exploratory tool for identifying seasonal patterns and monthly warming trends over time, complementary to the annual Warming Stripes. Interpretation is direct: the intensity of the red colour indicates the magnitude of warming relative to the historical baseline.

Technical Notes

The 1961–1990 baseline is the WMO climatological standard for computing anomalies
The visualisation covers the last 5 years of available data
The Z axis visually amplifies differences between months and years
Missing months (data not yet available) are omitted from the visualisation
Complementary to the annual Warming Stripes (id=79) for seasonal analysis

References

Hawkins, E. (2018). "Warming Stripes". University of Reading. https://showyourstripes.info
IPCC (2021). "Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report (AR6)". Cambridge University Press.
Hersbach, H. et al. (2020). "The ERA5 global reanalysis". Quarterly Journal of the Royal Meteorological Society, 146(730), 1999–2049.
Trenberth, K.E. (2011). "Changes in precipitation with climate change". Climate Research, 47(1-2), 123–138.

Data Sources & References

Sources

WRD_OPNMT_99

Methodology

Monthly temperature anomalies relative to the 1961–1990 baseline for the last 5 years. Source: Open-Meteo Historical Weather (ERA5-Land reanalysis, ~10 km, 1940–present). Calculation: monthly mean temperature for the last 5 years → 1961–1990 reference mean (WMO standard) → monthly anomaly = T(month, year) − historical mean(month). 3D visualisation: X axis = months (Jan–Dec), Y axis = years, Z axis and colour = anomaly (°C). Colouring: blue=cold, yellow=neutral, red=warm.