Satellite radar image of the magnitude 6.0 South Napa earthquake. The "fringe" rainbow pattern appears where the earthquake deformed the ground's surface, with one full cycle of the color spectrum (magenta to magenta) showing 3 centimeters of change. Satellite data like this can now be used to give researchers an understanding of an earthquake and its impacts within days. Credit: the European Space Agency.

When an earthquake hits, the faster first responders can get to an impacted area, the more likely infrastructure—and lives—can be saved.

New research from the University of Iowa, along with the United States Geological Survey (USGS), shows that GPS and satellite data can be used in a real-time, coordinated effort to fully characterize a fault line within 24 hours of an earthquake, ensuring that aid is delivered faster and more accurately than ever before.

Earth and Environmental Sciences assistant professor William Barnhart used GPS and satellite measurements from the magnitude 6.0 South Napa, California earthquake on August 24, 2014, to create a three-dimensional map of how the ground surface moved in response to the earthquake. The map was made without using traditional rapid response instruments, such as seismometers, which may not afford the same level of detail for similar events around the globe.

"By having the 3D knowledge of the earthquake itself, we can make predictions of the ground shaking, without instruments to record that ground shaking, and then can make estimates of what the human and infrastructure impacts will be— in terms of both fatalities and dollars," Barnhart says.

The study, "Geodetic Constraints on the 2014 M 6.0 South Napa Earthquake" published in the March/April edition of Seismological Research Letters, is the first USGS example showing that GPS and satellite readings can be used as a tool to shorten earthquake response times.

And while information about an earthquake's impact might be immediately known in an area such as southern California, Barnhart says the technique will be most useful in the developing world. The catastrophic magnitude 7.0 earthquake that hit Haiti in 2010 is the perfect example for the usefulness of this kind of tool, Barnhart says. The earthquake struck right under the capital city of Port Au Prince, killing up to 316,000 people, depending on estimates, and costing billions of dollars in aid.

"On an international scale, it dramatically reduces the time between when an earthquake happens, when buildings start to fall down, and when aid starts to show up," Barnhart says.

To accurately map the South Napa earthquake for this study, Barnhart and a team of researchers created a complex comparison scenario.

They first used GPS and satellite readings to measure the very small- millimeter-to-centimeter-sized-displacements of the ground's surface that were caused by the earthquake. They fed those measurements into a mathematical equation that inverts the data and relates how much the ground moved to the degree of slip on the fault plane. Slip describes the amount, timing, and distribution of fault plane movement during an earthquake.

This allowed the group to determine the location, orientation, and dimensions of the entire fault without setting foot on the ground near the earthquake. The mathematical inversion gave the researchers predictions of how much the ground might be displaced, and they compared those results to their initial estimations, bit by bit, until their predictions and observations match. The resulting model is a 3D map of fault slip beneath the Earth's surface. The entire procedure takes only a few minutes to complete.

Nationally, there is a push to create an earthquake early-warning system, which is already being tested internally by the USGS in coordination with the University of California, Berkeley; the California Institute of Technology; and the University of Washington. While only researchers, first responders, and other officials received the early warning message, it did work in testing for the Bay Area during the Napa earthquake. Individuals in Berkeley received nearly 10 seconds of advanced warning before the ground began shaking. The information contained in Barnhart's study could be used to create further tools for predicting the economic and human tolls of earthquakes.

"That's why this is so important. It really was the chance to test all these tools that have been put into place," Barnhart says. "It happened in a perfect place, because now we're much more equipped for a bigger earthquake."

Purified wastewater using membrane filtration. Credit: Teemu Leinonen, LUT

Contaminants such as medical residues and pesticides go through the traditional wastewater purifying process and go back to the environment. Concern over their volyme in waste and drinking water is growing globally. Research by Lappeenranta University of technology (LUT) found that by modernising the current wastewater purification process over 95 percent of contaminants can be removed from wastewater.

Improving the efficiency of the current wastewater cleaning process can remove more than 95% of contaminants, such as drug residues and pesticides, from water. These are the findings of research performed at Lappeenranta University of Technology (LUT).

Researchers tested the removal of drug residues using membrane filtration and oxidation. The results show that these technologies remove 95% and, in some cases, up to 99% of contaminants and nutrients. If they enter the water system, even very small concentrations of contaminants can damage the water ecosystems, for example, through hormonal changes in fish.

The research results show that more efficient water cleaning technologies, such as membrane filtration and oxidation, effectively remove substances that are normally difficult or impossible to remove in a biological cleaning process. Such substances include drugs for depression and epilepsy and pain gels that are applied externally.

"Generally speaking, drugs that act on the mind and the heart are the most difficult to remove," says LUT Professor Mika Mänttäri, who was responsible for the study.  

The research also demonstrated that increasing the efficiency of water treatment can also filter certain nutrients from the water. For example, phosphorous and nitrogen can be almost completely removed from the water. Membrane filtration reduced the amount of phosphorous to one tenth or even one hundredth of the emissions currently permitted. The water cleaning technologies that were tested can thus reduce emissions significantly in comparison to the water treatment process that is traditionally used. 

The wastewater cleaning process used today in nearly all municipalities only removes the substances that are readily biodegradable or which bind to the activated sludge in the process. Such substances include pesticides and basic pain medications that contain ibuprofen, paracetamol and ketoprofen. The process allows a lot of other non-biodegradable contaminants to pass through.

At this time, Finland does not have any wastewater treatment plants that are designed especially to filter drug residues out of the water. The situation is complicated by the fact that Finland does not have any general limit values for contaminants in the waterand, subsequently, no obligations to monitor or remove such substances. This means that existing wastewater treatment plants have no obligations or incentives to invest in new technologies.   

In the near future, the EU will make large treatment plants subject to monitoring requirements for certain priority substances. A monitoring requirement was already set for some substances last autumn. One of the substances being monitored is the anti-inflammatory drug diclofenac, which is used as the active ingredient in pain gels. Once the limit values are implemented, the current biological process will automatically be in trouble.

However, many municipalities are already discussing how wastewater treatmentshould be arranged in the future. The LUT researchers estimate that the next 5–10 years in Finland will be a transition phase to more efficient cleaning, as the environmental permits for many municipal treatment plants expire and the permit conditions become stricter over the next decade.