Maputo

Mozambique

Mozambique's capital, on the Indian Ocean coast at the mouth of the Maputo River, repeatedly struck by major tropical cyclones including Idai in 2019.

Population
2,384,312
Urban area
568 km²
Grid cells
695
H3 resolution
8

Overall hazard score

32/100

Moderate

Equal-weighted mean of the 6 indicators below, each on a fixed absolute scale.

Hazard profile

Flood33Earthquake0Cyclone16Wildfire89Extreme heat35Air quality23

Each axis is that hazard's score on its own fixed 0-100 scale. Adding more cities to this site never changes these values.

Where the risk sits

Loading map…

Air quality is published as a single figure per city, so it adds the same value to every cell. The variation on this map comes from the hazards that are mapped at grid resolution.

Showing combined score 0–20 Low 20–40 Moderate 40–60 Elevated 60–80 High 80–100 Very high

Each hexagon is about 0.74 km². Hover or tap one for its numbers, or switch the layer above to see a single hazard.

What drives the score

Flood

33

Expected annual inundation depth from river and coastal flooding combined, population-weighted across the city. From JRC CEMS-GloFAS river maps at 90 m (seven return periods) and WRI Aqueduct coastal maps (six). Both models are undefended: they simulate water without levees, sea walls or pumping.

Measured value: 0.005597 m/year

Population in 1-in-100y flood plain
5.5%
That is, people
131,672
Deepest modelled cell
5.52 m
Dominant mechanism
river

Earthquake

0

Distance-decayed, magnitude-weighted rate of observed earthquakes around the city, from the USGS ANSS catalogue.

Measured value: 0.007737 index/year

Catalogued events (M4.5+, 500 km)
48
Within 100 km
0
Largest magnitude
M5.6
Record
since 1970

Cyclone

16

Annual rate of tropical cyclone passages near the city, weighted by the sustained wind speed at closest approach. From NOAA IBTrACS, 1980 onwards.

Measured value: 0.02712 events/year

Storms within 200 km
4
Per year
0.09
At typhoon strength
0
Strongest approach
55 kt

Wildfire

89

Annual satellite fire-detection density in the vegetated ring around the city, from NASA FIRMS VIIRS 375 m.

Measured value: 122.6 detections/1000km²/year

Vegetation fire detections
28,933
Per year
2411.1
Interface ring
20 km
Record
since 2013

Extreme heat

35

Maximum temperature of the warmest month (BIO5, 1981-2010), averaged across the city. An absolute measure, comparable between climate zones. It does not account for humidity, so it understates the danger of humid tropical heat.

Measured value: 28.63 °C

Warmest month peaks at
28.6 °C
Hottest cell
29.7 °C
Warm days now (TX90p)
17.7%
Warm days since the 1970s
+3.1 points

Air quality

23

Population-weighted annual mean PM2.5 concentration. A chronic hazard rather than an episodic one - it harms through years of exposure, not in a single event - but by mortality it is the largest hazard on this site.

Measured value: 10 µg/m³

PM2.5 annual mean
10.0 µg/m³
Versus WHO guideline
2.0×
Attributed deaths per year
335

City profile

Context, not hazard. None of these figures affects the score above - a sunnier or greener city is not a safer one, and mixing the two would quietly change what the number means.

Solar potential

4.33kWh/kWp per day

Photovoltaic output for a standard panel. A resource, not a hazard.

World Bank Global Solar Atlas 2.0

Mean temperature

22.7°C

Annual mean, 2010s. Shown for context; the heat score measures departure from local normal, not absolute warmth.

GHS-UCDB climate reanalysis

Greenness

0.40NDVI

Mean vegetation index across the built-up area. Higher values moderate urban heat.

Landsat via GHS-UCDB

Hospitals

1.5per 100,000 people

Mapped health facilities per head. A rough proxy for capacity to respond, and dependent on how completely the country is mapped.

healthsites.io via GHS-UCDB

Average elevation

34m

Mean ground height across the urban centre.

Copernicus GLO-90

How to read this

Hazard, not risk after defences

The flood models simulate water without levees, sea walls or pumping, because global defence data does not exist at usable quality. Maputo's flood score therefore describes the exposure of the ground, not what remains after the engineering built on top of it.

Earthquakes: observed, not predicted

The earthquake score counts shaking that has actually happened since 1970. It cannot see a fault that has been locked and silent for centuries, so it understates places like Istanbul whose danger lies in a quake that has not arrived yet.

Scores are absolute, not a ranking

Every indicator is mapped onto a fixed scale chosen in advance. A score of 32 means the same thing today as it will when this site covers a hundred cities.

Not personal advice

These are city-scale estimates on a roughly one-kilometre grid. They say nothing reliable about an individual building, and nothing at all about what any person should do.

Checked against the source

The JRC publishes its own figures for these urban centres, computed independently from several of the same datasets. Every build compares our numbers against theirs and fails if the gap is too wide to explain. The result is printed here rather than kept private, because a score you cannot audit is not worth much.

Quantity Ours Reference Gap Status
Urban centre area Same polygon measured twice. Disagreement means our projection or area arithmetic is wrong. GHS-UCDB · GC_UCA_KM2_2025 567.60 570.00 0% agrees
Population Two different global population products (WorldPop against GHS-POP). They routinely differ by 10-20% for the same city. GHS-POP via GHS-UCDB · GC_POP_TOT_2020 2,384,312.00 3,533,370.36 32% warn
Population in the 1-in-100-year river flood plain Same flood model, independently aggregated. This is the check that would have caught the 90 m/1 km resolution bug. Baugh et al. (2024) via GHS-UCDB · EX_100_SHP_2020 5.52 1.57 252% fail
Population in the 1-in-10-year river flood plain Same flood model, independently aggregated. This is the check that would have caught the 90 m/1 km resolution bug. Baugh et al. (2024) via GHS-UCDB · EX_010_SHP_2020 3.22 0.22 1364% fail
Population exposed to coastal flood Investigated 2026-08-22: this gap is a model difference, not an aggregation bug. Aqueduct's historical coastal layer puts almost no water over Tokyo Bay (101 pixels above 1 cm in the whole city window), while UCDB's two coastal scenarios track the low-elevation coastal zone closely (CF2 8.9% against 8.2% of population below 5 m; CF1 21.0% against 17.2% below 10 m). Aqueduct appears to understate enclosed bays. Aqueduct is kept because it ships rasters and UCDB publishes only city totals, but a better coastal source is an open task. Vousdoukas et al. (2018) via GHS-UCDB · EX_CF2_SHP_2020 0.00 0.05 100% warn
Cyclone wind exposure Not the same quantity, so no ratio is computed: we count storm passages within 200 km, UCDB models whether category-1 wind actually reaches the built-up area. Tokyo reads 24 near-passages against 0% population in category-1 wind, which is consistent - typhoons pass close often, and hurricane-force wind rarely lands on the city. Shown side by side so a qualitative contradiction would be visible. GHS-UCDB cyclone wind exposure · EX_100_S1P_2020 0.00 0.00 n/a agrees

Units differ by row; each is given in the description. A gap of 10-20% is normal - the two sides use different population grids and different aggregation - and the tolerances are set accordingly.

Sources for this page

Generated 2026-08-23T12:17:49+00:00 from the underlying data.

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Maputo: 32/100 (Moderate) — City Risk Score