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Smog from cars and trucks is an expected health hazard in big cities, but researchers from the University of Cincinnati found pollution from truck exhaust on one of the most remote mountain roads in the world.
 

While climate scientists agree that human-caused climate change is influencing weather, they have often been hesitant to draw direct linkages between this phenomenon and specific extreme weather events. The reason? When studying a particular event such as a superstorm or severe heatwave, it can be challenging to tease apart human influence from the natural variability of the weather. But that’s changing.

In a new study, published in the journal Proceedings of the National Academy of Sciences, Stanford professor of Earth system science Noah Diffenbaugh and a team of colleagues outline a four-step framework for testing whether global warming has contributed to particular weather events. The collaborative effort involves researchers from several universities including Northwestern and is the latest in the growing field of “event attribution analysis,” which combines statistical analyses of climate observations with increasingly powerful computer models to study the influence of climate change on individual extreme weather events.

As electronics become increasingly pervasive in our lives – from smart phones to wearable sensors – so too does the ever rising amount of electronic waste they create. A United Nations Environment Program report found that almost 50 million tons of electronic waste were thrown out in 2017—more than 20 percent higher than waste in 2015. Troubled by this mounting waste, Stanford engineer Zhenan Bao and her team are rethinking electronics. “In my group, we have been trying to mimic the function of human skin to think about how to develop future electronic devices,” Bao said. She described how skin is stretchable, self-healable and also biodegradable – an attractive list of characteristics for electronics. “We have achieved the first two [flexible and self-healing], so the biodegradability was something we wanted to tackle.”

Solar cells based on perovskites reach high efficiencies: They convert more than 20 percent of the incident light directly into usable power. On their search for underlying physical mechanisms, researchers of the Karlsruhe Institute of Technology (KIT) have now detected strips of nanostructures with alternating directions of polarization in the perovskite layers. These structures might serve as transport paths for charge carriers. This is reported in the Energy & Environmental Science Journal.

The perovskites used by the KIT scientists are metal organic compounds with a special crystal structure and excellent photovoltaic properties. Since their discovery in 2009, perovskite solar cells have experienced a rapid development. Meanwhile, they reach power conversion efficiencies of more than 20 percent. This makes them one of the most promising photovoltaic technologies. Research into perovskite solar cells, however, faces two special challenges: The light-absorbing layers have to be made more robust to environmental impacts and the lead contained therein has to be replaced by environmentally more compatible elements. This requires in-depth understanding of physical mechanisms that enable the high conversion rate of absorbed solar energy into electric power. 

A new WCS study reveals evidence that some corals are adapting to warming ocean waters – potentially good news in the face of recent reports of global coral die offs due to extreme warm temperatures in 2016. The study appears in the latest issue of Marine Ecology Progress Series.

The study looked at responses to extreme temperature exposures in the same reefs over time, and found less coral bleaching in 11 of the 21 coral species studied. WCS Senior Conservation Zoologist Tim McClanahan, who has been studying coral responses to climate change since the extreme temperatures of the1998 El Nino, authored the study.