environment

When wildfire smoke is in the air, doctors urge people to stay indoors to avoid breathing in harmful particles and gases. But what happens to trees and other plants that can’t escape from the smoke? They respond a bit like us, it turns out: Some trees essentially shut their windows and doors and hold their breath. As atmospheric and chemical scientists, we study the air quality and ecological effects of wildfire smoke and other pollutants. In a study that started quite by accident when smoke overwhelmed our research site in Colorado, we were able to watch in real time how the leaves of living pine trees responded. How plants breathe Plants have pores on the surface of their leaves called stomata. These pores are much like our mouths, except that while we inhale oxygen and exhale carbon dioxide, plants inhale carbon dioxide and exhale oxygen. A highly magnified view of stomata in a maize leaf. Umberto Salvagnin/Fli...

The most significant predictors of bug biodiversity in Los Angeles are proximity to the mountains and temperature stability throughout the year, according to a study we co-authored with Brian V. Brown of the Los Angeles Natural History Museum and colleagues at the University of Southern California and California State University. The project used data from the museum’s BioSCAN project, where volunteers across Los Angeles allowed insect traps to be installed on their property between 2014 and 2018. Arthropod species richness in Los Angeles. Black dots show locations where the BioSCAN project collected bugs between 2014-2018. The color scale shows the predicted number of species, with blue being the least rich and orange being the most rich. Map tiles by Stamen Design, CC BY-SA The analysis showed some surprising results. For instance, land values had little impact on the overall diversity of art...

Storm-chasing for science can be exciting and stressful – we know, because we do it. It has also been essential for developing today’s understanding of how tornadoes form and how they behave. In 1996, the movie “Twister” with Helen Hunt brought storm-chasing scientists into the public imagination and inspired a generation of atmospheric scientists. With the new “Twisters” movie hitting theaters, we’ve been getting questions about storm-chasing – or storm intercepts, as we call them. Here are some answers about what scientists who do this kind of fieldwork are really up to when they race off after storms. Scientists with the National Severe Storms Lab ‘intercepted’ this tornado to collect data using mobile radar and other instruments on May 24, 2024. National Severe Storms Lab What does a day of storm-chasing really look like? The morning...

A month into summer 2024, the vast majority of the U.S. population had already experienced at least one extreme heat wave, and millions of people were under heat alerts, with forecasts warning of more ahead. Death Valley hit 125 degrees Fahrenheit (51.7 Celsius) or higher for nine consecutive days in early July. Las Vegas broke its all-time heat record at 120 F (48.9 C). Days of 100-degree heat dried out the California landscapes, fueling wildfires there and in the Northwest. Oregon reported several suspected heat deaths. Globally, the planet had its hottest day in at least eight decades of recordkeeping on July 21 – and then broke the record again on July 22, according to the European Union’s Copernicus Climate Change Service. The extreme heat is part of a longer trend: Each of the past 13 months has been the hottest on record for that month globally, including the hottest June, the EU service reported in early July. It also found that the average temperature for t...

Strange as it may seem, early germ theorists could tell us a lot about today’s attitudes toward climate change. While researching for a new book about the history of emerging infections, I found many similarities between early debates over the existence of microbes and current debates over the existence of global warming. Both controversies reveal the struggles of perceiving an unseen threat. Both reveal the influence of economic interests that benefit from the status quo. But most importantly, both reveal how people with different beliefs and interests can still agree on key policies and practices for tackling a global problem. What you can’t see might hurt you Seeing is believing, and until the mid-19th century, it was very difficult to see the tiny organisms responsible for our so-called “fever” diseases. Although the indirect evidence was compelling, many people remained skeptical of “animalcules” – as microorganisms were once cal...