Editor's Note: The Commerce Data Service recently launched the Commerce Data Usability Project to feature tutorials and case studies in order to assist data scientists, programmers, researchers and other data users access and utilize a range of Commerce Department datasets. As part of this project, a number of external organizations are sharing tutorials illustrating their innovative use of Commerce data. In the guest blog below, Mapbox explains how to visualize NOAA precipitable water data. To learn more about this project, visit www.commerce.gov/datausability.
Atmospheric Rivers (AR) are narrow regions in the atmosphere that transport water across the world. Like a river suspended in the air, these phenomena carry moisture from the humid tropics to temperate areas, where it has the potential to fall as rain or snow. ARs can range in size, and we depend on them to resupply water reserves. However, when a large AR stalls over an area, it also can bring the risk of heavy, damaging rainfalls and flooding.
How do we know when an AR is carrying moisture our way? Among the many meteorological indicators that are collected by the National Oceanic & Atmospheric Administration (NOAA) is Precipitable Water (Pwat), which is the amount of water that can be extracted from the entire overlying atmosphere over a particular location on the surface of the Earth. Pwat is a key measure of the available "fuel" for the storms in the atmosphere and an estimate for much rain or snow could be produced from those storms.
Beyond its utility, Pwat is a very striking weather variable. The complex swirling and eddying patterns bring alive atmospheric processes, and are a beautiful liquid analog to the more esoteric variable that they describe. Combining this data with reference information - coastlines, political borders, and terrain - helps to paint a clearer picture of earth surface and atmospheric interactions on our planet. By enabling access to weather data processing and visualization tools, more designers and developers will be able to create beautiful custom maps.
In collaboration with the Commerce Data Service, Mapbox has created a two part tutorial that will guide you though processing and visualizing Pwat data. Get started with Part 1 of the tutorial or checkout the Github project.
Expect part 2 of the tutorial next month, where we'll teach out you to create a video-based animated map of this data like this: