Kraków, Poland in top 5 worst air quality worldwide

Main suspected causes

• Consensus that residential heating is the dominant source: widespread burning of coal, wood, very low‑quality fuels, and often household trash in old, inefficient stoves and boilers.
• Car traffic and older vehicle fleet add NOx and particulates, but several commenters say winter smog remained severe even when COVID cut traffic to near zero.
• Industrial coal plants are seen as comparatively better filtered; the real issue is “small sources” in homes and villages around Kraków.

Topography, weather, and regional inflow

• Kraków sits in a basin/valley with frequent temperature inversions and little wind, so pollutants accumulate and “can’t escape.”
• Pollution drifts in from surrounding municipalities and regional coal‑burning areas; nearby small towns and villages are often described as worse than the city itself.

Local practices and attitudes

• Burning trash (including plastics, treated wood, coal dust) is reported as common in poorer or rural areas, driven by cost and habit; smell is described as acrid and pervasive.
• Some describe a “post‑communist” mentality: low regard for common goods like clean air, resistance to regulation, and prideful non‑compliance.
• Others emphasize poverty and energy insecurity over mentality.

Policy and infrastructure responses

• Kraków banned solid fuels in 2019 and introduced a clean transport zone; many coal boilers were replaced. Some residents say air quality has improved measurably; others claim it “feels the same.”
• A dense sensor network makes Kraków’s problem highly visible; nearby jurisdictions still freely burn coal and trash, and the city has no authority over them.
• Upgrading stoves, adding heat pumps, district heating, and insulation is seen as effective but very costly and slow.

Debate over energy mix

• Disagreement over whether German energy policy and nuclear phase‑out are relevant; multiple commenters say Poland’s own heavy coal use is the key driver.
• Heated argument over nuclear: some call it “dirty,” others argue it’s among the cleanest options per kWh with small land and material footprint compared to coal and some renewables.
• Natural gas is broadly viewed as much cleaner locally than coal/wood, though still a climate problem.

Data and ranking skepticism

• Several note IQAir’s ranking covers only a limited set of cities, uses short‑term hourly data, and partly crowdsourced sensors of unknown calibration and placement.
• Others cross‑check with alternative networks and personal sensors, confirming extremely high PM2.5 levels on bad days, regardless of IQAir’s methodology.