TWELVE REGIONS, ONE RANKING, NO CONTEST

Each bar is how much warmer the previous decade was, compared to the 1980s, for one region of the planet. Six are land, six are ocean. They start dead level in 1988 and then they separate.

The rule shows up almost immediately: land warms faster. By the end the land regions average 1.66 degrees above the 1980s, the ocean regions 0.90. Land is warming about 1.85 times faster than the sea. Land has no depth to hide the heat in and no evaporating surface to spend it on, so what arrives stays near the ground.

THE OCEAN'S OWN RANKING

Forty seven years of sea surface temperature, lining up one by one.

Same period and same rules as the air temperature race we published: each bar is one complete year, every month weighted by its length, every cell weighted by the surface it actually covers. A year is born at the bottom of the ranking, grows into its own value, overtakes whoever it can on the way up, and then stops. A year only gets one number and it keeps it forever.

THE RACE NOBODY WANTED TO WIN

Forty seven years of global air temperature, lining up one by one.

Each bar is a complete year: the average temperature of the whole planet, every month weighted by how long it lasts, every grid cell weighted by how much surface it actually covers. A year is born at the bottom of the ranking, grows into its own value, and overtakes whoever it can on the way up. Then it stops, because a year only gets one number and it keeps it forever.

Since the 1980s, satellites and reanalysis models have let scientists track how surface temperature is changing, not just on average, but region by region. This animation shows the linear trend in 2-metre air temperature (ERA5 reanalysis, 1979-2025) across the globe, in K/decade. The surface is both colored and deformed by the trend: it bulges outward where warming is fastest, and dips inward in the rare pockets that have cooled. To be clear, this is a visualization device, not a physical measurement.

A follow-up to the annual version of this animation (ERA5, 1940-2025): same reanalysis, same 1991-2020 baseline, but this time month by month instead of year by year, and starting in 1982 instead of 1940 to keep the frame count manageable. Going monthly changes what the animation shows. The annual version told the story of the long-term trend, decades slowly shifting from blue to red.

We know, we live in a changing world. How temperature is evolving is just a measure for that change and how we might be feeling it.

Here we have 61 years of changing global temperatures (Data exported from ERA5).

Data: ERA5

Ocean temperature doesn't just respond to a warming atmosphere, it also stores the overwhelming majority of the extra heat trapped by greenhouse gases, over 90% of it. This animation shows the linear trend in sea surface temperature (ERA5 reanalysis, 1940-2025, 86 years of data) across the globe, in K/decade. Land is shown in flat gray; the trend is oceanic only.

From 1940 to 2025, sea surface temperature compared to the 1991-2020 average. Blue, cooler. Red, warmer. One frame per year.

The map is a Spilhaus projection: it cuts the planet through the continents instead of through the ocean, so you see in one piece what we always treat as four separate oceans. It's one.

The sea has absorbed close to 90% of the excess heat from global warming. This animation is that bill, year by year.

Data: ERA5, Copernicus Climate Change Service (C3S)