Data

It’s been a warm day, maybe even a little humid, and the tall clouds in the distance remind you of cauliflower. You hear a sharp crack, like the sound of a batter hitting a home run, or a low rumble reminiscent of a truck driving down the highway. A distant thunderstorm, alive with lightning, is making itself known. Lightning flashes in thunderstorms at least 60 times per second somewhere around the planet, sometimes even near the North Pole. Each giant spark of electricity travels through the atmosphere at 200,000 miles per hour. It is hotter than the surface of the sun and delivers thousands of times more electricity than the power outlet that charges your smartphone. That’s why lightning is so dangerous. Lightning kills or injures about 250,000 people around the world every year, most frequently in developing countries, where many people work outside without lightning-safe shelters nearby. In the United States, an average of 28 people were killed by lightning ev...

If you want to track changes in the Amazon rainforest, see the full expanse of a hurricane or figure out where people need help after a disaster, it’s much easier to do with the view from a satellite orbiting a few hundred miles above Earth. Traditionally, access to satellite data has been limited to researchers and professionals with expertise in remote sensing and image processing. However, the increasing availability of open-access data from government satellites such as Landsat and Sentinel, and free cloud-computing resources such as Amazon Web Services, Google Earth Engine and Microsoft Planetary Computer, have made it possible for just about anyone to gain insight into environmental changes underway. I work with geospatial big data as a professor. Here’s a quick tour of where you can find satellite images, plus some free, fairly simple tools that anyone can use to create time-lapse animations from satellite images. For example, state and urban planners –...