Hurricane Maria laid waste to several Caribbean islands, roaring through the Commonwealth of Dominica as a Category 5 and stripping the entire island of Puerto Rico of foliage and power as a Category 4. She's moving out to sea now, but she left an unfathomable amount of devastation in her wake, and the citizens of Puerto Rico desperately need our help to survive. You can donate to many excellent relief organizations who will put your dollars to good use. You can also help a friend's grandmother who broke her hip during the hurricane.

You may think of hurricanes strictly in terms of weather, but they have a profound impact on geology. And while the USGS is the agency that studies rocks, earthquakes, and volcanoes, they also study another geologic process: flooding. If hurricanes are good at anything, it's causing flooding. The flooding in turn causes some pretty impressive geomorphological changes – some of which are permanent. All of the above can have profound effects on humans.

An aerial view of damage caused by Hurricane Maria. A huge building has had its roof shredded to ribbons.Other buildings have had bits ripped off.
Damage to buildings and trees in Puerto Rico caused by Hurricane Maria. Credit: Sgt. Michelle Gonzalez, U.S. Army National Guard Staff Flickr (CC BY 2.0)

Before a hurricane strikes, USGS personnel scramble to the waterways and shores in the storm's path. When the hurricane makes landfall, the USGS is there to monitor its effects and advise federal and state agencies, first responders, and local officials in real time. And when the storm has passed, USGS scientists fan out through the disaster zone to repair equipment, take readings, and provide the information people need to recover from disaster and better prepare for the next one.

How to Measure a Hurricane

The USGS already studies American waterways and coastlines. Before a hurricane, they go into high gear to prepare the necessary equipment.

One of the most important instruments they use is a storm-tide sensor. These steel-wrapped instruments are mounted on coastal structures that have a high probability of making it through a hurricane. They collect information that allows scientists to determine when the storm surge arrived, how deep it was, how long it lasted, and when it ebbed. That information is vital for separating wind from water damage – and when you're talking about a storm with winds over a hundred miles an hour, that can be difficult! Those readings also provide critical information that will help us better forecast what future hurricanes might do.

Stream gauges record the height and flow rate of floodwaters. They allow us to see floods moving downstream, which helps officials determine who to evacuate, which reservoirs to lower, and make other crucial decisions to protects life and property.

Permanent sensor networks installed along America's East Coast , which provide vital data to the National Weather Service, FEMA, and other agencies responsible for forecasting, emergency response, disaster relief, and evacuation.

USGS computer models allow scientists to determine what effects a storm may have on coastal erosion, protective dunes and barrier islands.

The US Army Corps of Engineers sometimes ask the USGS to install webcams to help them monitor water releases from reservoirs during storms.

Floodwaters not only spread mud and disease, but invasive species. Computer tools created by the USGS allow conservationists to see where floodwaters may have deposited them, so they can be handled before they become a problem for a new area.

And the USGS is now using drones to take photographs of coastal dunes and other features before and after storms. Those photos allow us to quantify the changes the storm has made.

Image shows a woman in an orange USGS long-sleeved t-shirt attaching a Barometric pressure sensor on a utility pole.
A USGS scientist mounts a barometric pressure sensor on a utility pole at Puerto Chico Bay Dock, Fajardo, PR. Credit: U.S. Geological Survey 

Fieldwork in the Time of Hurricanes

Before the storm, USGS scientists fan out to the area in the forecasted path of the storm, quickly installing necessary equipment. They also forecast what the storm might do to sand dunes, beaches, barrier islands, and other features of the coastline. This information is crucial for emergency managers, helping them with evacuation plans, likely safe routes, and where they can stash equipment that will be needed to clear away the devastation after the storm.

During the storm, the USGS's Geospatial Information Response Team helps make sense of the data pouring in, and provide information and maps to folks in the field. Some USGS staffers are also boots on the ground, installing emergency monitoring equipment and keeping up with the rapidly developing situation as they work closely with other agencies.

After the storm comes the hardest work. Scientists fan out in the field, repairing storm-damaged equipment, and investigating the after-effects of the hurricane. They look for high-water marks: things like stranded lines of seeds, silt, and debris that tell them where the waters reached before they receded. They retrieve sensors deployed before the storm, and validate the flood measurements taken during the worst of it. The data they gather helps FEMA and other agencies identify the areas hardest hit, and help direct relief efforts to where they're needed the most.

Storm Science Matters

Data on hurricanes collected and studied by the USGS helps us prepare for future storms. New data helps the USGS refine and improve the flood inundation maps that help cities, counties, and states decide where to build and where to not, and how to build in order to accommodate the inevitable natural disasters. All of those data points help the USGS refine their forecasts, allowing us to better predict the impact of future storms. This is especially important in an era where global warming is fueling stronger storms.


Sources and further reading:

Throughout Hurricane Season, USGS Science is There Before, During, and After the Storm

USGS Continues Response to Four Hurricanes

USGS field crews in Puerto Rico are preparing for Hurricane Maria

Hurricane Maria

Water Resources of Florida and the Caribbean