Climate change
People often think of disasters as great equalizers. After all, a tornado, wildfire or hurricane doesn’t discriminate against those in its path. But the consequences for those affected are not “one-size-fits-all.” That’s evident in recent storms, including the widespread storms that brought deadly tornadoes and downpours to several states over the 2024 Memorial Day weekend, and in the U.S. Census Bureau’s national household surveys showing who was displaced by disasters in 2023. Overall, the Census Bureau estimates that nearly 2.5 million Americans had to leave their homes because of disasters in 2023, whether for a short period or much longer. However, a closer look at demographics in the survey reveals much more about disaster risk in America and who is vulnerable. It suggests, as researchers have also found, that people with the fewest resources, as well as those who have disabilities or have been marginalized, were more likely to be displaced f...
When people talk about the “Anthropocene,” they typically picture the vast impact human societies are having on the planet, from rapid declines in biodiversity to increases in Earth’s temperature by burning fossil fuels. Such massive planetary changes did not begin all at once at any single place or time. That’s why it was controversial when, after over a decade of study and debate, an international committee of scientists – the Anthropocene Working Group – proposed to mark the Anthropocene as an epoch in the geologic time scale starting precisely in 1952. The marker was radioactive fallout from hydrogen bomb tests. On March 4, 2024, the commission responsible for recognizing time units within our most recent period of geologic time – the Subcommission on Quarternary Stratigraphy – rejected that proposal, with 12 of 18 members voting no. These are the scientists most expert at reconstructing Earth’s history from the evidence...
As the Arctic warms, its mighty rivers are changing in ways that could have vast consequences – not only for the Arctic region but for the world. Rivers represent the land branch of the earth’s hydrological cycle. As rain and snow fall, rivers transport freshwater runoff along with dissolved organic and particulate materials, including carbon, to coastal areas. With the Arctic now warming nearly four times faster than the rest of the world, the region is seeing more precipitation and the permafrost is thawing, leading to stronger river flows. Major river basins of the Arctic region. NOAA Arctic Report Card We’re climate scientists who study how warming is influencing the water cycle and ecosystems. In a new study using historical data and sophisticated computer models of Earth’s climate and hydrology, we explored how climate change is altering Arctic rivers. We found that th...
Superstorms, abrupt climate shifts and New York City frozen in ice. That’s how the blockbuster Hollywood movie “The Day After Tomorrow” depicted an abrupt shutdown of the Atlantic Ocean’s circulation and the catastrophic consequences. While Hollywood’s vision was over the top, the 2004 movie raised a serious question: If global warming shuts down the Atlantic Meridional Overturning Circulation, which is crucial for carrying heat from the tropics to the northern latitudes, how abrupt and severe would the climate changes be? Twenty years after the movie’s release, we know a lot more about the Atlantic Ocean’s circulation. Instruments deployed in the ocean starting in 2004 show that the Atlantic Ocean circulation has observably slowed over the past two decades, possibly to its weakest state in almost a millennium. Studies also suggest that the circulation has reached a dangerous tipping point in the past that sent it into a precipitous, uns...
E-bikes have captured widespread attention across the U.S., and for good reason. They are the most energy-efficient way to move from place to place, providing exercise in the process, and offer enough assistance while pedaling uphill or into headwinds to make them usable for many types of riders. Greenhouse gas emissions from e-bikes are much lower than those from either gasoline-powered or electric cars. Some cities and states are encouraging the use of e-bikes by providing purchase incentives, often drawing on public funds dedicated to curbing climate change. Currently, over 100 cities and states have or plan to launch e-bike incentive programs, most funded by energy or environment initiatives. However, there has been little research on the effectiveness of these types of programs, how to design them or how to define goals. We study transportation from many angles, including innovation, sustainability and economics. Our new study, published in the journal Transportation Res...