Your street – and your roof – may be polluting the air as much as your car

Extreme rising temperatures are known to increase the risk of environmental hazards like drought and wildfires. But new research published last week in Science Advances adds another danger to the list: extreme heat sends harmful emissions into the air courtesy of hot asphalt…The study, published by a team of Yale researchers, reveals that asphalt is likely an overlooked but major source of hazardous pollutants being released into the air.

“A main finding is that asphalt-related products emit substantial and diverse mixtures of organic compounds into the air, with a strong dependence on temperature and other environmental conditions,” says Peeyush Khare, a Yale chemical and environmental engineer and the lead author of the study…

On a typical summer day in Los Angeles, asphalt can reach to 140 degrees Fahrenheit. At this threshold, the asphalt will release a steady and significant stream of emissions. Under these conditions, scientists predict hot asphalt could become a long-lasting source of pollution…

Researchers estimated that in California’s South Coast Air Basin, the total amount of aerosols formed from hot asphalt emissions is comparable to those released by gas and diesel motor vehicles…

And in some environments, the pollution from asphalt can be higher than internal combustion engines powering our transport.

Major cache of fossils unearthed in L.A.

Workers excavating an underground garage on the site of an old May Co. parking structure in Los Angeles’ Hancock Park got more than just a couple hundred new parking spaces. They found the largest known cache of fossils from the last ice age, an assemblage that has flabbergasted paleontologists.

Researchers from the George C. Page Museum at the La Brea tar pits have barely begun extracting the fossils from the sandy, tarry matrix of soil, but they expect the find to double the size of the museum’s collection from the period, already the largest in the world.

Among their finds…is the nearly intact skeleton of a Columbian mammoth — named Zed by researchers — a prize discovery because only bits and pieces of mammoths had previously been found in the tar pits.

But researchers are perhaps even more excited about finding smaller fossils of tree trunks, turtles, snails, clams, millipedes, fish, gophers and even mats of oak leaves. In the early 1900s, the first excavators at La Brea threw out similar items in their haste to find prized animal bones, and crucial information about the period was lost.

“This gives us the opportunity to get a detailed picture of what life was like 10,000 to 40,000 years ago” in the Los Angeles Basin, said John Harris, chief curator at the Page. The find will make the museum “the major library of life in the Pleistocene ice age,” he said.

RTFA. The details of the find are interesting enough. New methods devised for rapid excavation and storage are fascinating.