Micro urban heat islands

MUHID

Finds the few small hotspots that overheat whole districts, so one tree or one water basin can cool a neighbourhood.

Micro urban heat islands marked in red on a satellite image of Hamburg around the Alster

The challenge

Heat waves are getting longer and hotter, but urban climate analyses are elaborate and expensive. That is why most cities commission them only every five years, and why the results are too coarse to say where exactly a measure should go.

Our approach

MUHID is affordable, fast and precise. It identifies the hottest places of a city at 10 × 10 metres from satellite data. A micro forest or a small water surface on one of these small hotspots can lower the temperature of the whole district. Minimal intervention, maximum effect.

From hotspot to measure.

Three steps from satellite image to cooler district.

Satellite image of Hamburg around the Alster with micro urban heat islands marked in red
1

Find the hotspot

MUHID marks the places that are hottest relative to their surroundings, at a resolution of 10 × 10 metres: remarkably precise for temperature detection.

Micro urban heat islands (red) on a Sentinel-2 image

A single large tree on a small green island in a plaza between high-rise buildings
2

Act small

Because the hotspot is small, the measure can be small: a micro forest, an unsealed surface or a water basin, exactly where it cools most.

One tree, one surface, one water basin: measures the size of a hotspot

A small child playing barefoot in a shallow water feature on a city square
3

Check the effect

MUHID updates weekly. The next weeks of data show whether the hotspot has cooled, and the district with it.

What it is all about: a cooler city for the people who live in it

Left: a city skyline at sunset in orange heat haze. Right: a fountain with high water jets in a tree-lined city park

A single tree, a new surface or a small water basin can cool a whole neighbourhood. If you know where to put it.

Why MUHID.

Usual climate analyses are imprecise, expensive and quickly outdated. MUHID is precise, affordable and available any time, for any city in the world. And it matters most where summers are hottest.

Precise to 10 × 10 metres

Not a district average, but the exact spot. Fine enough that a single tree, a new surface or a small water basin becomes a meaningful measure.

Weekly instead of every five years

Satellites pass every few days. MUHID updates weekly and compares across seasons and years, so measures can be checked instead of assumed.

Measured, not simulated

MUHID uses the surface temperature the satellite actually measured, not a model of buildings and wind flow.

A fraction of the cost

No simulation, no field survey, no sensors. MUHID is simple to use, and it scales to any city, anywhere.

Where MUHID helps

  • High-resolution maps of micro urban heat islands
  • The coolest places of the city, on request
  • Prioritising trees, water and shade where they cool most
  • Evidence of whether measures actually work

Who MUHID is for

  • Cities and municipalities
  • Climate adaptation managers
  • Urban and landscape planners
  • Housing companies and campus operators

Nominated for the KOINNO Award 2025. Data: Sentinel-2, Landsat 8.

Daniel Lanz

Interested in MUHID?

Tell us which city you want to cool down, and we’ll show you where to start.

Daniel Lanz

Email Daniel+49 (0)2207 9610 551

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