Mapping the Damage in Puerto Rico


At NASA’s Earth Observatory, before and after images of Puerto Rico’s nighttime lights illustrate the extent of power outages and infrastructure damage on the island. NASA has also produced a map of likely damaged areas of eastern Puerto Rico, based on before and after radar satellite interferometry and similar to the map they produced for the Mexican earthquake. At ground level, the CrowdRescue Puerto Rico Infrastructure Map displays crowdsourced reports of damage—downed power lines, bridge collapses, floods, mudslides and other incidents.

Mapping the Earthquake in Central Mexico

The New York Times

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.

Maria’s Deluge

Some of the most striking maps of the recent bout of hurricanes have involved the sheer amount of water dropped by these storms. (See previous posts on Harvey and Irma.) Above, a is a short NASA video showing Maria’s track through the Caribbean, dumping water in its wake.

Relatedly, the Washington Post produced maps of precipitation and river gauge levels on Puerto Rico that show just how much water Maria threw at that island.

Washington Post

Predicting Future Malaria Outbreaks from Satellite Data

Data from NASA’s earth-observing satellites is being used to predict future malaria outbreaks in the Amazon rainforests of Peru. To be sure, as the above video shows, this is really about taking geospatial and remote sensing data from several different sources and correlating them to build a predictive model: it’s John Snow’s cholera map at large scale and for the satellite age.

New Gravity Map of Mars

NASA/Goddard/UMBC/MIT/E. Mazarico

A new gravity map of Mars that shows the thickness of the Martian crust based on gravity measurements from Martian orbiters, reveals a crust that is less dense and shows less variation than earlier maps. “The researchers mapped the density of the Martian crust, estimating the average density is 2,582 kilograms per meter cubed (about 161 pounds per cubic foot). That’s comparable to the average density of the lunar crust. Typically, Mars’ crust has been considered at least as dense as Earth’s oceanic crust, which is about 2,900 kilograms per meter cubed (about 181 pounds per cubic foot).”

NASA Images of Hurricane Harvey

Hurricane Harvey on 26 Aug at 5:45 PM CDT (2245 UTC), as captured by NOAA’s GOES-East satellite. Credits: NASA/NOAA GOES Project.

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.

The Earth at Night, Updated

NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center.

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.

John M. Nelson, “A Changing Earth at Night,” 2017.

Mapping Arctic Warming

At All Over the Map, Betsy Mason posts 11 Ways to See How Climate Change Is Imperilling the Arctic, a collection of maps and infographics depicting several different indicators of global warming, including sea ice extent, atmospheric temperatures, growing season, polar bear populations, as well as projected shipping routes for an ice-free Arctic Ocean.

NASA Earth Observatory

Meanwhile, NASA Earth Observatory points—while it still can—to a study mapping the extent of existing and potential thermokarst (thawed permafrost) landscapes. On the Earth Observatory maps (see North America, above), “[t]he different colors reflect the types of landscapes—wetlands, lakes, hillslopes, etc.—where thermokarst is likely to be found today and where it is most likely to form in the future.”

Previously: Mapping Arctic Sea IceMapping the Thaw.

November Sea Ice


NASA Earth Observatory: “In November, the sea ice extent averaged 9.08 million square kilometers (3.52 million square miles)—the lowest November extent in the satellite record. The yellow line shows the median extent from 1981 to 2010, and gives an idea of how conditions this November strayed from the norm.” Also shows sea ice extent for previous years dating back to 1978. Hudson Bay was icebound in November not that long ago.

Previously: Mapping Arctic Sea Ice.

Mapping Arctic Sea Ice


Something’s going on in the Arctic. As the Washington Post reported last month, the Arctic Ocean was far, far warmer than normal—about 20 degrees Celsius higher than average. (Meanwhile, the air over Sibera is at record cold levels.) According to the Post, the higher temperatures are the result of record low amounts of thinning sea ice, as well as warm air being brought north by an increasingly errant jet stream.

NASA has been tracking sea ice levels and thickness by looking at the age of the ice in the sea ice cap. The video above shows “how Arctic sea ice has been growing and shrinking, spinning, melting in place, and drifting out of the Arctic for the past three decades. The age of the ice is represented in shades of blue-gray to white, with the brightest whites representing the oldest ice.”

The ESA reports that their CryoSat satellite “has found that the Arctic has one of the lowest volumes of sea ice of any November, matching record lows in 2011 and 2012.” The animated GIF below shows the change in November sea ice from 2011 to 2016, as observed by CryoSat.


Hurricane Matthew Map Roundup


Start with the National Hurricane Center, which has lots of different maps of Hurricane Matthew’s predicted path, weather warnings, rainfall potential and so forth. See also maps from Weather Underground.

Google’s Crisis Map includes evacuation resources—Red Cross shelters, evacuation routes, traffic data—in addition to storm track and precipitation information.

Matthew has already struck southwest Haiti; the Humanitarian OSM Team has put out a call for crisis mappers on the following projects: buildings in Nippes; road network in Grand’Anse and Sud.


Wind maps from Windytv and EarthWindMap visualize the wind patterns of Matthew and, further out in the Atlantic, Nicole.

Hurricane imagery from NOAA’s GOES East satellite. NASA Earth Observatory has imagery of Matthew’s path toward Florida.

[Dave Smith/Maps Mania/NASA Earth/NOAA Satellites]

Louisiana Flooding: NASA Animation of Accumulated Rainfall


NASA Earth Observatory: “Days of intense rainfall in August 2016 led to widespread flooding in southern Louisiana, as rivers swelled high above their banks and many crested at record-high levels. […] The animation above shows satellite-based measurements of the rainfall as it accumulated over the southern United States. Specifically, it shows rainfall totals every three hours over the span of 72 hours from August 12-14, 2016. These rainfall totals are regional, remotely sensed estimates, and local amounts can be significantly higher when measured from the ground.”

New Orleans Is Sinking


“New Orleans and surrounding areas continue to sink at highly variable rates due to a combination of natural geologic and human-induced processes,” according to the findings of a new study that maps the rate at which New Orleans is sinking.

The maps were created using data from NASA’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), which uses a technique known as interferometric synthetic aperture radar (InSAR). InSAR compares radar images of Earth’s surface over time to map surface deformation with centimeter-scale precision. It measures total surface elevation changes from all sources—human and natural, deep seated and shallow. Its data must be carefully interpreted to disentangle these phenomena, which operate at different time and space scales. UAVSAR’s spatial resolution makes it ideal for measuring subsidence in New Orleans, where human-produced subsidence can be large and is often localized.