Climate observations
Live over NOAA's Global Historical Climatology Network — a 9.20 GB public Parquet dataset on S3, read in place with HTTP range requests. Nothing is downloaded or copied.
Public role · 9 columns visible · 1 withheld
14,031 files · 1750–2026
Selects a partition
Selects partitions
Grain
~14 MB
per request
Observations
3.9M
2025–2025, TMAX
Mean
16.92 °C
across every matching reading
Range
-75.5 – 51.6
°C, lowest to highest recorded
95th percentile
34.4 °C
across every matching reading
Maximum temperature over time
Grouped on a substring of the raw YYYYMMDD column rather than a parsed timestamp — the same answer, measured 3.7× faster over two million rows.
Seasonality
Month of the year across the whole range, ignoring which year each reading fell in — another substring of the same column.
Scanning Parquet
By country
Grouped on a code taken from the station ID — GHCN's own FIPS encoding — so this is one scan with nothing joined to it. The name is filled in from the catalog.
Scanning Parquet
Read 13.4 MB from 8 of 14,031 files · 9.20 GB dataset · fetched once, then read from memory
0.1456% of the dataset