Lab Notes | Analysis · 25 May 2026

First Week of Atmospheric Data: KTM-001

📍 Kathmandu, Nepal

Seven days of continuous environmental data from our Kathmandu station. Clear diurnal temperature cycle, morning PM2.5 peak correlating with traffic and cooking hours, and a stable pressure pattern. Notes on data quality and next steps.

Temperature

Clear diurnal cycle: 18–20°C overnight, 28–32°C mid-afternoon. The cycle is remarkably consistent across the week, with a 2°C dip on the one overcast day (Day 4).

Air Quality (PM2.5)

Morning peak between 06:00–09:00 local time, coinciding with cooking and commuter traffic. Values reach 80–120 µg/m³ during the peak, dropping to 15–30 µg/m³ by early afternoon. WHO guideline (15 µg/m³ 24-hour mean) is exceeded on every day of the first week.

Pressure

Barometric pressure at 1,350m altitude averages ~865 hPa. Semi-diurnal tide pattern is clearly visible in the high-resolution (1-minute) data. No significant weather events during the first week.

Data Quality

99.7% uptime — one 18-minute gap on Day 3 when the sync script crashed and was restarted. All readings within expected ranges. The CO₂ sensor (MH-Z19B) takes ~48 hours to stabilise after power-on; first two days excluded from analysis.