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🌡️ Climate CMIP6 Open-Meteo 16 cities 7 models

Every Model Warms Every City. None Agree By How Much.

Seven downscaled climate models, 16 cities, the twenty years to 2010 against the twenty to 2050. Every model warms every city — the coolest projection anywhere in the set is still +0.03°C. What they disagree about is the amount, by a median 0.51°C, which is 43% of the warming itself.

16 of 16
Cities where every model projects warming
0.51°C
Median disagreement between models
43%
That disagreement, as a share of the warming
3
Cities where the spread exceeds the warming
Data Source
Coverage
16 cities · 7 models · 111 city-model pairs · 1991–2010 against 2031–2050
Agreement
Every model warms every city; the ensemble's coolest projection anywhere is still +0.03°C
Licence
CC BY 4.0 (Open-Meteo)
Key Takeaways

Across 16 cities and 7 models there is no disagreement about direction at all: 16 of 16 cities are warmed by every single model, and the most conservative projection anywhere in the set is +0.03°C. The disagreement is entirely about how much.

  • Median warming across these cities is 1.08°C and the median gap between the highest and lowest model for the same city is 0.51°C43% of the warming being projected.
  • In 3 cities the models disagree by more than the warming they are disagreeing about. Delhi is the widest: a mean of 0.72°C spanning 0.03°C to 1.57°C. Sydney is the tightest at 0.28°C.
  • Manila — the city behind this site’s Philippine climate page — warms 0.9°C on the ensemble mean, across a range of 0.21 to 1.14°C. That earlier page found two reconstructions of the observed past differing by 1.09°C, so a 0.93-degree spread on the future is the expected shape.
  • The hot-day figures are where the spread stops being abstract. Cairo goes from 63.9 to 81.6 days above 35°C a year on the ensemble mean — 17.7 more — and the models’ range for that one number is 11.8 days.
  • Geography explains less than expected. Latitude and warming correlate at only 0.4 across these cities: New York at 40.7°N warms 1.76°C, more than Reykjavik at 64.2°N, which warms 1.12°C.

There Is No Argument About The Direction

This has to come first, because everything after it is about disagreement and would read differently otherwise. Across 111 city-model pairs, not one projects cooling.

Warming projected for each city: the ensemble mean, and the full range across models

Cities warmed by every model
16 of 16

Not most models, and not on average. Every model, every city.

The most conservative projection anywhere
+0.03°C

The single coolest of all 111 city-model pairs. The bottom of this ensemble is still warming.

Median warming
1.08°C

Ensemble mean across the 16 cities, 1991–2010 against 2031–2050.

The Amount Is Another Matter

A projection is usually quoted as one number. Underneath it are 7 numbers that disagree, and the width of that disagreement is a median 0.51°C.

The gap between the highest and lowest model for each city, against the warming they are projecting

Median spread
0.51°C

Between the warmest and coolest model for the same city. As a share of the warming itself: 43%.

Delhi
0.03–1.57°C

The widest in the set, around a mean of 0.72°C. Which number you quote depends on which model you opened.

Cities where the spread wins
3

Places where the models differ from each other by more than the warming they are projecting. Sydney is the opposite case, tightest at 0.28°C.

Manila, And The Page This One Extends

This site already has a Philippine climate page. It compared two reconstructions of the observed past and found them 1.09°C apart on Manila’s annual mean. That was history. This is the future.

Days a year above 35°C, baseline against future, with the range across models

Manila’s warming
0.9°C

From 26.82°C to 27.72°C on the ensemble mean.

Across the models
0.21–1.14°C

A 0.93-degree spread on one city. The observed-past disagreement was 1.09°C, so this is not a new problem appearing in projections.

Days above 35°C
9.8 → 16.9

Per year, baseline against future, ensemble mean. The models range from 7.2 to 26.6 for that future figure.

Geography Explains Less Than You Would Expect

The far north is supposed to warm fastest, and across these 16 cities latitude and warming correlate at only 0.4. The disagreement between models is larger than the geographical signal it is supposed to reveal.

Warming against latitude, one point per city

Latitude against warming
r = 0.4

Across all 16 cities. A relationship exists and it is weak enough that the ordering is not what a map would predict.

The fastest-warming city
New York, 1.76°C

At 40.7 degrees north — warming more than Reykjavik, which sits at 64.2 degrees and warms 1.12°C.

The slowest
Delhi, 0.72°C

Tied with Dhaka on exactly that figure — and also the city with the widest disagreement in the set, which is the next section and is not a coincidence.

The City The Ensemble Cannot Agree On

Delhi is tied with Dhaka for the lowest mean warming in this set, and has by far the widest range behind it. The models are not slightly apart; they describe two different futures.

Every model's projection for every city, one row per city

Ensemble mean
0.72°C

Equal lowest of the 16 cities. Read alone it looks like the least-affected place in the set.

The models
0.03–1.57°C

One model projects 0.03°C across twenty years — almost nothing, and still positive. Another projects 1.57°C.

Spread against warming
2.13×

A 1.54°C spread around a 0.72°C mean. Quoting the mean alone would be the single most misleading number on this page.

What A Spread Is And Is Not

The number this page reports is the range across models of a single scenario. Three things it does not measure, and one it does.

Not scenario uncertainty

Every model here is run on the same emissions pathway. The spread is what remains after that choice is fixed: different physics, different resolution, different treatment of clouds and land. Adding scenarios would widen it further, most at longer horizons.

Not error bars on an observation

None of these numbers is a measurement. They are what several independent models produce when asked the same question, and the agreement between them is evidence about the models rather than about the atmosphere.

Not a reason to discount the direction

A wide spread around a robust sign is the ordinary condition of this field, and it is why 16 of 16 cities here are warmed by every member of the ensemble while none of the members agree on the amount. Reporting the second without the first would be a different and dishonest page.

It is a reason to distrust one decimal place

A city plan built on a single downscaled projection is built on one draw from a distribution 0.51°C wide at the median. The useful output is the range.

What These Numbers Are Not

Four limits, and the first two bound how far anything above travels.

A subset of CMIP6, not the ensemble

These are the high-resolution members Open-Meteo redistributes, downscaled to a 10km grid: 7 models, not the several dozen the IPCC assesses. A different subset would give a different spread, and this one is not weighted by skill.

16 cities, chosen for latitude

Points, not regions, and picked to span from Reykjavik at 64.2 degrees north to Sao Paulo at 24 south rather than sampled at random. Nothing here is a global average and no global figure is quoted. Collection is limited by a daily cap on the source and this set is what a day of it buys.

Twenty-year windows, near-term

1991–2010 against 2031–2050, because the source's coverage ends at 2050. Near-term is where model choice matters most relative to scenario choice, which flatters the finding and is worth saying.

A downscaled point is not a station

Each value is a model grid cell interpolated to a coordinate, not a thermometer in that city. Absolute temperatures carry a bias that mostly cancels in the difference between two windows, which is why this page reports warming rather than temperature.

Key Findings & Summary

  • 16 of 16 cities are warmed by every one of the 7 models. The coolest projection anywhere is +0.03°C.
  • Median warming is 1.08°C and the median disagreement between models for the same city is 0.51°C43% of it.
  • In 3 cities the spread exceeds the warming. Delhi spans 0.03 to 1.57°C.
  • Manila warms 0.9°C across a 0.93-degree spread, against the 1.09°C two reanalyses of its observed past already disagree by.
  • Cairo gains 17.7 days a year above 35°C on the ensemble mean, with a 11.8-day range between models.
  • Latitude and warming correlate at only 0.4: New York warms 1.76°C at 40.7°N against Reykjavik’s 1.12°C at 64.2°N.
  • Delhi is the extreme case: a 0.72°C mean over a 0.03 to 1.57°C range — a spread 2.13 times the warming.

Sources & Citations

Every figure on this page traces to one of these, through a CSV in data/global-climate-spread/. Each is checked against its source query on every build.

Daily mean and maximum temperature for a point from seven downscaled CMIP6 models, 1991-2050, for 30 cities — Free, no key. Coverage ends at 2050 and a request past it returns 400 rather than a truncated series, which is why the future window here is 2021-2050. The parameter is `models`; sending `model` as well is also a 400.

CMIP6Primary

The model intercomparison project the underlying projections come from — Cited for provenance. The models here are the high-resolution HighResMIP members Open-Meteo redistributes, downscaled to a 10km grid; they are a subset of CMIP6 and not the full ensemble the IPCC assesses.

The observed-past counterpart: two ERA5 reanalyses of the same Philippine record disagreeing by 1.09 C on Manila's annual mean — This page is the projection-side extension of that one. The comparison is deliberate: if two reconstructions of what already happened differ by a degree, a spread between projections of what has not happened yet is the expected shape rather than a surprise.