Ever wonder how the weatherman predicts the weather? Turns out it's math. Lots of math.
Through a method known as numerical weather prediction, the state of weather is found in the future via solving several fluid- and thermo- dynamic differential equations. This is done by supercomputers which are given data in the form of an "initial" fluid information (pressure, density, temperature, etc) from weather centers which monitor the local conditions. From the local data, an idea of the future state of the fluid can be found.
Similarly, atmospheric dispersion are modeled to give an idea of how particulate matter will travel. This is done to have an idea of where potentially bad stuff will go in the case of an incident that causes an emission in to the air. Examples of concerning emissions include smoke from fires, as well as chemical or radioactive releases.
In the case of some particulate pollutant that has a local source, a similar method to meteorological prediction is employed. Local weather information is processed to predict the direction and area of dispersal. Additionally, the density of the emission material is considered as a source term. That is, if the source is only a small leak then there will be less pollution than a giant gap, so the amount of the emission from the leak is measured and used to predict the severity.
I wonder what the actual equations used are. Does everyone use the same equations? Or are they proprietary knowledge that gives some weather services a competitive advantage?
ReplyDeleteFrom my reading, I believe that there are multiple models which use different spins on the same idea. Then, all data is made publicly available (at https://www.ncdc.noaa.gov) and the various forecasters can pick and choose what data to interpret and use within their predictions.
DeleteThese supercomputers probably do an unimaginable amount of grinding, but sadly it's only a tiny fraction of the work required to have close to 100% accurate models. My high school Calculus teacher (Literally the smartest guy I know; he taught for fun.) used to develop meteorological models for the Air Force. He told us that until we can track and model every single, individual atom in our atmosphere, that we will never have a model that's even close to 100% accurate.
ReplyDeleteI imagine it has to be along the lines of predicting the Butterfly Effect, down to each individual atom effected. Crazy to think about.
We have difficulty describing 3-body systems accurately, so its safe to say that absent of some mathematical paradigm shift, an n-th body system description is part of a wild dream.
DeleteWeather certainly is one of the more complicated things we attempt to model, however. And meteorologists don't do too shabby of a job.