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 4 and 5-band 3-meter imagery daily! In the March edition of Our Changing Landscape we investigated the incredibly fast construction of a coronavirus hospital in China, and for the April edition we stay focused on the pandemic with a look at one of the world’s busiest ports, Yangshan Deep Water Port outside of Shanghai, China, from December 2019 to April 2020.
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.
Tracking Shipping Traffic at Yangshan Deep Water Port From December 2019 to April 2020
While the economic devastation caused by the coronavirus is a distant second in importance to the health-crisis it has caused, it cannot be ignored. Most of us can look out our windows (keep in mind this was written in early April 2020 so it could be dated by the time you read our May edition of the Geospatial Times) to see empty roads and businesses closed up and down our streets. As in last month’s Our Changing Landscape, it is not the purpose of this article to recount the extreme economic hardships caused by the coronavirus (here is an excellent April summary of that topic put together by the BBC), rather it is to help us visualize the dramatic impact it has had on one of the world’s busiest docks, i.e. Yangshan Deep Water Port.
Just ten years ago, Yangshan was little more than a group of tiny islands in the East China Sea. But as China has done with other small atolls in the region, they poured millions of tons of sand and rocks into the ocean to create what eventually will be the largest deepwater port in the world. According to a 2017 news article, Yangshan will eventually feature 26 bridge cranes and 120 rail-mounted cranes able to handle some 6.3 million TEUs (twenty-foot equivalent units – or a single shipping container about 20 feet long by 8 feet tall and 8 feet wide) per month. While COVID-19 was not declared a global pandemic until March 11, 2020, China initiated strict lockdown measures in Hubei on January 23rd to stem the spread of the virus. These measures appears to have been successful as they were slowly lifted in late March. The 3-meter PlanetScope images picked for this article were collected from December 2019 to April 2020 so they should show normal December shipping traffic, then a severe depression in activity during February, and finally a recovery in March and April. There are now fears of a second wave of shipping dips as coronavirus grips the rest of the world driving down global demand – perhaps we will continue this investigation in a future edition of Our Changing Landscape then; but for now it is time to check out what we can see in these 3-m PlanetScope images!
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.