Volunteers Mapping Post-Hurricane Puerto Rico

When disaster strikes, crowdmapping kicks into high gear. Last Friday, six universities hosted mapathons where volunteers, using satellite imagery, contributed to the map of Puerto Rico and other hurricane-damaged areas on OpenStreetMap. More from one of the universities involved. Here’s the relevant project page on the OSM Wiki.

Mapping the Damage in Puerto Rico

NASA-JPL/Caltech/ESA/Copernicus/Google

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.

Looking Back at Hurricane Harvey’s Impact

Here’s a CBS News gallery of before-and-after images showing the impact of flooding in the wake of Hurricane Harvey. The page is undated but was published on 1 September. [Dave Smith]

And, via CityLab, here are a set of maps from the Urban Institute that show the impact of Hurricane Harvey on Houston’s neighbourhoods, based on income levels, home ownership rates, accumulated-equity rates, all of which looking at the economic impact of the storm. “Harvey’s aftermath puts an enormous hurdle in front of all homeowners and renters but will be a particular setback for low-income, minority families recovering from the 2008 housing bust.”

Previously: Mapping Hurricane Harvey’s Impact.

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

Tracking Hurricane Irma

Washington Post

As they did with Hurricane Harvey, both the New York Times and the Washington Post graphics departments have frequently updated map pages showing the projected path and impact of Hurricane Irma. The Times’ page looks at the hurricane’s current and projected path, threat of coastal flooding, and areas under evacuation, plus some context; the Post maps Irma’s forecasted path on this page and the potential storm surge and evacuation zones on this page, while this page compares Irma’s size to past hurricanes.

Debunking a Fake Hurricane Map

Also from last week: someone on Facebook circulated a map showing the path of Hurricane Irma hitting Houston, prompting the National Weather Service to issue a warning on Twitter about fake forecasts (real forecasts only go out five days). Media factchecking service PolitiFact has the details. Fun fact: making a counterfeit or false weather forecast is an offense in the United States.

Mapping Hurricane Harvey’s Impact

Washington Post

The Washington Post maps rainfall and flooding levels in the Houston area.

The New York Times is collecting several maps on two web pages. The first page deals with subjects like rainfall, river level, current and historical hurricane tracks, damage reports, and cities and counties under evacuation orders. Maps on the second page look at Harvey’s impact on the Houston area.

Esri’s U.S. Flooding Public Information Map includes precipitation and flood warnings.

Kenneth Field critiques the National Weather Service’s decision to add more colours to their precipitation maps (see above). “Simply adding colours to the end of an already poor colour scheme and then making the class representing the largest magnitude the very lightest colour is weak symbology. But then, they’ve already used all the colours of the rainbow so they’re out of options!”

Extreme Event Attribution

Whenever a cataclysmic weather event occurs—like Hurricane Harvey right now—there’s usually a heated political argument over whether or not it can be blamed on climate change. It turns out that there’s a field of research dedicated to assessing whether extreme weather can be attributed to climate change: it’s called extreme event attribution. There have been more than 140 peer-reviewed attribution studies of extreme weather events around the globe, which Carbon Brief has mapped here.

Carbon Brief’s analysis suggests 63% of all extreme weather events studied to date were made more likely or more severe by human-caused climate change. Heatwaves account for nearly half of such events (46%), droughts make up 21% and heavy rainfall or floods account for 14%.

[Benjamin Hennig]

FEMA Flood Maps Don’t Account for Future Sea Level Rise

NPR last month, reporting on a problem with FEMA’s flood insurance maps: they’re not keeping up with reality. “FEMA’s insurance maps are based on past patterns of flooding. Future sea level rise—which is expected to create new, bigger flood zones—is not factored in. So some communities are doing the mapping themselves. Like Annapolis, the state capital of Maryland.” [Leventhal]

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.

Mapping Global Landslide Susceptibility

Image: Jesse Allen. Landslide susceptibility data: Thomas Stanley and Dalia Kirschbaum (NASA/GSFC). Topographic data: SRTM. (NASA Earth Observatory)

NASA Earth Observatory notes the release of a new map of global landslide susceptibility that models the risks of landslides that are triggered by heavy rain. “The map is part of a broader effort to establish a hazards monitoring system that combines satellite observations of rainfall from the Global Precipitation Measurement (GPM) mission with an assessment of the underlying susceptibility of terrain.” [Geographical]