In this monthly feature, we span the globe to examine Our Changing Landscape with a time series of medium-resolution PlanetScope satellite imagery. The PlanetScope constellation dates back to 2016 and collects hundreds of millions of square kilometers of four and five-band 3-meter imagery daily! In May we were in the Middle East looking at a blockage of one of the world’s busiest canals, and for this June edition of Our Changing Landscape we head to the United States to the site of an early Spring tornado in Alabama.
The PlanetScope Microsat Constellation
PlanetScope is a constellation of more than 150 microsats referred to individually as Doves. Each Dove is able to collect up to 20,000 square kilometers (sq km) per day of 3-meter (m) 4-band multispectral (i.e. blue, green, red and near-infrared [NIR]) imagery; and newly launched SuperDoves collect 5-band multispectral adding in valuable red-edge spectral data. Across the constellation, PlanetScope is archiving more than 200 million sq km of medium-resolution imagery a day, making it the go to source for daily imagery over most locations. This massive archive dates back to 2016, offering the most complete and continuous record of spatial data on the planet since the start of the constellation’s ongoing launch schedule. Collecting 3-meter multispectral imagery is the equivalent of ‘high-resolution’ multispectral data imaged by a 75-centimer (cm) satellite (as this satellite would feature 75-cm panchromatic and 3-m multispectral), making PlanetScope an extremely competitively priced option at just $1.80 per sq km. With well registered images and nearly daily collections of most locations, PlanetScope is the ideal imagery source for this current-events focused series,
Our Changing Landscape.
March 2021 Tornado over Eagle Point, Alabama
Eagle Point, Alabama is a small census-designated place in the Birmingham metro region. With a total area of about 2 square miles (5 square kilometers), Eagle Point is home to some 3,600 residents and it borders Birmingham on its northern edge. Alabama is no stranger to tornadoes as it is part of the region called the Dixie Alley in the south-eastern United States where tornadoes are common from October through December. Within Alabama, Shelby County where Eagle Point is located, has moderate tornado risk as compared to all of the counties in the state with 38 touch-downs from 1950 to 2018. And as you likely have guessed, global climate change has increased this frequency in the past decades as Alabama has been struck more often by tornadoes with a record 145 touching down in 2011 alone.
March 25, 2021 was a very active night in the Dixie Alley region with at least 14 tornadoes reported in Alabama and Mississippi. These tornadoes killed five people and damaged hundreds of homes. The twister that struck the Eagle Point community was recorded as an EF-3 tornado, which is considered a strong event with wind speeds of 136 to 165 miles per hour (218 to 266 kilometers per hour). While on-ground recordings of the tornado show just how powerful it was, thankfully no deaths were reported in Eagle Point. Now it is time to turn to the 3-meter PlanetScope archive to see if the damage from the storm is visible from space.
If you would like to find out more about using 3-meter PlanetScope imagery for your academic studies, engineering projects or any landscape analysis, let us know at [email protected] or (303) 993-3863.