Smoke from the British Columbia wildfires (previously) has blanketed the Canadian prairie provinces and can be seen from space, CBC News reports. The above image was taken by the Suomi NPP satellite on 15 August.
Landsat observations have charted the erosion of the banks of the ever-changing Padma River, a major distributary of the Ganges in Bangladesh. This is vividly shown in this animation produced by NASA Earth Observatory, which “shows 14 false-color images of the Padma river between 1988 and 2018 taken by the Landsat 5 and 8 satellites. All of the images include a combination of shortwave infrared, near infrared, and visible light to highlight differences between land and water.” More on the erosion of the Padma River here.
The Washington Post maps the largest of the wildfires burning in northern California: the Carr Fire threatening the city of Redding and surrounding communities. The Redding Record Searchlight has drone footage of the destruction wreaked by the Carr Fire in Shasta County. NASA has natural and false-colour imagery (Earth Observatory, Visible Earth) of the Carr Fire, as well as the Ranch and River Fires to the south, the so-called Mendocino Complex. See the Mercury News’s fire map of the Mendocino Complex, whose two fires’ combined acreage is now larger than the Carr Fire. Meanwhile, German astronaut Alexander Gerst observed the California wildfires from the International Space Station. [San Francisco Chronicle]
Daily Overview is a website that curates spectacular aerial and satellite imagery. Founded by Benjamin Grant, and inspired by the Overview Effect—”the sensation astronauts have when given the opportunity to look down and view the Earth as a whole,” it’s available in virtually every social media format out there; a book, Overview, came out in October 2016. [WMS]
Last October Robin Kraft posted an online map of the northern California wildfires showing satellite imagery from before and after the fires (see previous entry); today he’s posted a blog entry explaining how he built it, in great technical detail. The timing is not accidental: “There is another fire raging in Los Angeles right now — if DigitalGlobe and Planet release their data, you can use this guide to make your own map.”
There are many circumstances where the amount of data vastly exceeds the ability to process and analyze it—and computers can only do so much. Enter crowdsourcing. Steve Coast points to Digital Globe’s Tomnod project, which basically crowdsources satellite image analysis. In the case of the current project to map the presence of Weddell seals on the Antarctic Peninsula and the ice floes of the Weddell Sea, users are given an image tile and asked to indicate whether there are seals in the image. It’s harder than it looks, but it’s the kind of routine task that most people can do—many hands, light work and all that—and it helps researchers focus their attention where it needs focusing. (A similar campaign for the Ross Sea took place in 2016.)
Another ongoing campaign asks users to identify flooded and damaged infrastructure and trash heaps in post-Hurricane Maria Puerto Rico.
This NOAA article looks at three kinds of imagery provided by the GOES-16 geostationary weather satellite: GeoColor, the Geostationary Lightning Mapper (!), and full disk infrared imagery from the Advanced Baseline Imager. GOES-16 launched last November and is currently in the checkout phase before it replaces GOES-13 at 75° west latitude.
Maps and satellite imagery of the wildfires in Northern California include the San Francisco Chronicle’s interactive map; Robin Kraft’s interactive map showing satellite imagery from before and after the fire; this New York Times page mapping building damage in Santa Rosa; the Washington Post’s coverage of the devastation; and NASA Earth Observatory’s images of the smoke plumes here and here.
This crowdsourced map of collapsed and damaged buildings in Mexico City (in Spanish) appeared shortly after the 7.1-magnitude earthquake hit central Mexico on 19 September [via]. NASA also produced a map, based on radar data from the ESA’s Copernicus satellites that compared the state of the region before and after the quake. Interestingly, the data was validated against the crowdsourced map.
The New York Times produced maps showing the pattern of damage in Mexico City and the extent and severity of earthquake shaking (the Times graphics department’s version of the quake’s Shake Map, I suppose) as well as how Mexico City’s geology—it was built on the drained basin of Lake Texcoco—made the impact of the quake much worse.
Today Esri is proud to announce that we are making our own global collection of satellite imagery available to the OSM community directly through our existing World Imagery Service. This regularly updated resource provides one meter or better satellite and aerial photography in many parts of the world, 15m TerraColor imagery at small and mid-scales (~1:591M down to ~1:72k), 2.5m SPOT Imagery (~1:288k to ~1:72k), 1 meter or better NAIP in the US and many other curated sources, so we know it will make a welcome addition to OSM’s growing catalog of reference layers.
OSM editors have been able to trace maps from satellite imagery for years; other sources of such imagery have included Bing and Yahoo (back when Yahoo Maps was a thing). Different sources have different strengths, so this can only help the project. (Esri’s imagery makes no difference where I am, but that’s not a surprise.)
NASA’s page on Hurricane Harvey has been updated many times, sometimes several times a day, since Harvey began its life as Tropical Depression 9 on 17 August. It includes plenty of satellite imagery of the storm, as well as temperature and rainfall maps.
NASA has released updated global maps of the Earth at night. The so-called “black marble” maps show where human activity lights up the darkness. NASA’s page highlights some of the differences between the 2016 and 2012 versions of the map with before/after interactive sliders. John Nelson has tried something different: overlaying the 2016 map on the 2012 map with a clipping mask shows newly illuminated parts of the globe as dark patches.
The Arctic Journal reports on recent efforts to produce more detailed, systematic and accurate maps of Greenland.
Danish officials today announced promising initial results of a project using satellites to collect cartographic data faster and more efficiently than has been possible using aeroplanes.
The project involved using SPOT 6 and 7, two commercially operated European satellites, flying at an altitude of 700km to collect images of four specific areas […]. The pictures they returned over a two-year period beginning in 2015 each measure 360 square km. Objects as small as 1.5 m can be discerned in the pictures, making them detailed enough to be used to make precise, high-resolution maps.
Cartographers are now in the process of turning the data into finished, on-line maps. The maps themselves are expected to publicly available by autumn. But, even before that, the data gathered by the satellites will be placed on-line.
Meanwhile, the Ottawa-Gatineau urban agglomeration (which is, as urban areas go, the closest to where I currently live) has, according to the census, grown by 5.5 percent since 2011, to a total population of 1.3 million. Much of that growth has occurred in suburbs that barely existed even when I moved to the region in 1999. This CBC Ottawa feature uses the Google Earth engine’s timelapse video function to chart the growth of seven of those suburbs. (Above: the Gatineau suburb of Aylmer.)