Get atmospheric pressure values through JavaScript

Question

I'm working on a programming project in which I want to show isobars on a map with OpenStreetMap and the HTML tag canvas. The main problem that I'm facing is the dificulty of retrieving consistent data to draw the isobars and, therefor, calculate wind speed and direction.

I gave up trying to find real time data, and also I'm starting to doing so about getting open sea data (atmospheric pressure and temperature data in open sea, the first idea I had). So, right now, I'm searching for a platform where I can retrieve this kind of data in Europe (Spain in particular would be very nice) so I can start working on drawing isobars and calculating wind variables. I looking for measurements with some density (for example, 200 or 300 points of measurement across Spain within 4 times in a day) to draw the isobars.

The best (and kind of only) way to do so would be in JSON, because it would be quite easy to manipulate and work with the data, but also plain text would work.

Thanks to anyone who answers me.

Answer 1

There are some problems with your request, and maybe some misunderstandings.

Misunderstanding: You actually need more than pressure to get wind vectors. Wind speed is nonlinear, and is dependent on more than just wind. Even if you had observations of pressure, that will only tell you how the wind is changing due to the pressure gradient force, and not due to things like transport, diffusion, or Coriolis force, especially at the resolution you are requesting. Fortunately, wind observations are much easier to get than pressure observations, so that lies in your favor. You could use satellite data to get wind data, or near the surface.

Problem: Observations aren't really on a structured grid (unless you are working with satellite data, which has quality problems), nor are they available at the resolution you want. You may be able to use model data or reanalysis data, but even the resolutions you request may not be sufficient.

You can interpolate down to whatever resolution you want.

If you want near realtime model data for Europe, try the GFS model from the WPC. You can try to get data from the ECMWF (perhaps they have data sources I am unaware of), but their data is proprietary. You may also want to use a grib reader to access the data. If you are familiar with Python, you can use pygrib. Or you can refer to the ECMWF recommendations on reading grib files. I'm a little unfamiliar with satellite-derived products, so I can't really help you there.