Growing Degree Days calculator
This page is plain Markdown prose, exactly like the home page, up until the point where a small self-contained HTML+JS widget is dropped in as a raw block. Quarto/Pandoc passes a {=html} block straight through to the rendered HTML file, untouched — that’s the mechanism for embedding the kind of public micro-app you host on Cloudflare, but directly inside a static page here.
Growing degree days (GDD) is a standard day-degree accumulator used in crop phenology: GDD = max(0, (Tmax + Tmin) / 2 - Tbase), in degC·day. Tmin and Tmax are the daily air temperature extremes — in the dX/dt = f(X, p, u(t), w(t)) framing this is elsewhere, these two numbers are a w(t) weather driver, and Tbase is a parameter p. This widget only computes one day’s value; accumulating over a season is the natural next step once real driver data is wired in (e.g. fetched from a Cloudflare Worker instead of typed by hand).
Nothing above calls out to a server — it’s pure client-side JS, safe to publish as-is. The moment a widget needs real weather data, a lookup table, or logging of who used it, that’s the cue to have it call a Cloudflare Worker endpoint via fetch() instead of adding any backend logic to this static site.