A burning-activity calendar from two generations of NASA satellites, made to agree.
Every number says how sure it is.
MODIS has watched since 2000, VIIRS since 2012. Over south-east Australia in 2019 they counted 50,497 and 631,751 hotspots: 12.5 times apart.
VIIRS is mapped onto MODIS tile by tile, fitted on the years both saw. On 2019, a year the fit never saw, the gap falls from 12.5 times to 0.77.
Months across, years down: south-east Australia from November 2000 to December 2019, from NASA FIRMS. The darker the cell, the more hotspots.
A median December here has 7. The month rises past its uncertainty and past every year before it, so it carries the diamond: unusual, and not a change of sensor.
2009, 2001 and 2002, compared by rank within each month, so a quiet place and a busy one are judged the same way. History, not a forecast.
Each dot is a month of 2019, each black tick its median over the years before, each blue line its uncertainty at two sigma. Most months sit near their past.
A month is flagged only when it rises past its band and past every year before it. In 2019 that is November and December.
firecal is a static site. Pinning keeps the tiles of a region in the browser: 4.21 MiB for this one.
Draw a new area and it still answers, in under a millisecond: the same Rust core that harmonized twenty years of satellites runs in the browser.
The science is one Rust core. On a laptop it ingests and harmonizes twenty years of FIRMS; compiled to WebAssembly, the same code answers in your browser. There is no server: the site is static files.
The browser build and the laptop build give identical bytes on 8,968 test calls, and every change is checked on macOS, Windows and Linux before it is merged.