Skip to content
Airleaf

Bydgoszcz vs Erlangen

Tree cover and air quality for both, measured the same way: Sentinel-2 imagery at 10 m detail over a 2 km radius from each city centre, and the live US EPA air quality index. Same radius and same index, so the two numbers compare directly.

Erlangen has more tree cover — 50.7% against 37.8%.

Erlangen has cleaner air right now — AQI 35 against 88.

Tree cover gap
12.9 points
Erlangen is ahead.
Air quality gap
53 AQI
Erlangen is cleaner.
Trees between them
40.5K
Erlangen has more standing.
Bydgoszcz

Poland

Erlangen

Germany

Tree cover

Share of the 2 km radius under canopy.

37.8%

50.7%

Air quality index

US EPA index, live, with its band. Lower is better.

88 · Moderate

35 · Good

Trees standing

Estimated from the measured canopy area.

119K

159K

Trees still needed

To reach the same canopy target. Fewer is better.

0

0

CO₂ absorbed each year

By the trees already standing.

2.6M kg

3.5M kg

Air quality in detail

What each city is breathing

Concentrations in µg/m³, measured at the same moment as the index above. Lower is better in every row. Both are read from nearby ground stations.

PM2.5

Fine particles, the pollutant that usually sets the index.

29.8 µg/m³

8.4 µg/m³

Nitrogen dioxide

Mostly traffic and combustion.

22.1 µg/m³

10.5 µg/m³

Ozone

Forms in sunlight; peaks on hot, still afternoons.

61.5 µg/m³

49.9 µg/m³

The last week, day by day

A single reading can catch a city on a bad afternoon. The week says whether it was the weather or the place.

BydgoszczErlangen· daily US EPA index, last 7 days
0387522 Sept25 Sept28 Sept
Daily air quality index for Bydgoszcz and Erlangen
DayBydgoszczErlangen
22 Sept2431
23 Sept2733
24 Sept5141
25 Sept3738
26 Sept4949
27 Sept6242
28 Sept6039

Reading these numbers

What is actually being measured

Tree cover

The share of ground under canopy inside a 2 km radius of each city centre, read from Sentinel-2 satellite imagery at 10 m detail. It is a measurement of that circle, not of the whole municipality — which is exactly what makes the two comparable, since city boundaries are drawn to wildly different rules around the world. Erlangen leads here at 50.7%.

Air quality index

The live US EPA index, computed from current pollutant concentrations — ground stations where a city has them nearby, and a model everywhere else. It moves hour to hour, so this is a snapshot rather than a verdict on either place: Bydgoszcz reads 88 (moderate) and Erlangen reads 35 (good) right now.

Frequently asked

Bydgoszcz and Erlangen, answered

Which has more trees, Bydgoszcz or Erlangen?

Erlangen, with roughly 159,279 trees inside its 2 km radius against 118,752. Tree cover tells a slightly different story from raw count: Erlangen has the denser canopy at 50.7%.

Which has better air quality, Bydgoszcz or Erlangen?

Erlangen right now, at AQI 35 against 88 — a gap of 53 points. This is a live reading rather than an annual average, so it can reverse within a day.

How many more trees does each city need?

Bydgoszcz needs about 0 more to reach its canopy target, and Erlangen about 0. The target is the same share of ground for both, so the figures are directly comparable.

Are these two measured the same way?

Yes — that is the point of the page. Identical radius, identical satellite source at 10 m detail, and the same US EPA index for air. Nothing here is adjusted for population, city limits or climate, so the numbers describe the same-sized circle of ground in each place.

Keep going

Other comparisons nearby

Build your own

Compare Bydgoszcz with somewhere else

This place

Bydgoszcz

Want a different pair? Browse comparisons or measure any address.