Climate change

This summer has shown how quickly high temperatures can pose serious health risks, with record-breaking heat waves claiming thousands of lives around the world. However, it’s not just high and low temperatures that matter. How many degrees the temperature swings within a day – the daily temperature variation – itself poses health risks. Studies have found that days with larger than normal temperature swings can increase asthma flare-ups and hospitalizations for respiratory and cardiovascular diseases, leading to an overall higher death rate than normal. One study, based on data from 308 cities from 1972 to 2013, estimates that 2.5% of deaths in that time could be attributed to large daily temperature swings. Although humans can live in a wide range of ambient temperatures, a dramatic shift in temperature can tax multiple systems in the body, including the immune, musculoskeletal and cardiovascular systems. It can be especially taxing on very young and older in...

Tropical Storm Debby was moving so slowly, Olympians could have outrun it as it moved across the Southeast in early August 2024. That gave its rainfall time to deluge cities and farms over large parts of Florida, Georgia and the Carolinas. More than a foot of rain had fallen in some areas by early Aug. 7, 2024, with more days of rain forecast there and into the Northeast. Mathew Barlow, a climate scientist at UMass Lowell, explains how storms like Debby pick up so much moisture, what can cause them to slow or stall, and what climate change has to do with it. What causes hurricanes to stall? Hurricanes are steered by the weather systems they interact with, including other storms moving across the U.S. and the Bermuda High over the Atlantic Ocean. A hurricane may be moving slowly because there are no weather systems close enough to pull the hurricane along, or there might be a high-pressure system to the north of the hurricane that blocks its forward movement. In this case,...

As we focused our microscope on the soil sample for the first time, bits of organic material came into view: a tiny poppy seed, the compound eye of an insect, broken willow twigs and spikemoss spores. Dark-colored spheres produced by soil fungi dominated our view. These were unmistakably the remains of an arctic tundra ecosystem – and proof that Greenland’s entire ice sheet disappeared more recently than people realize. These tiny hints of past life came from a most unlikely place – a handful of soil that had been buried under 2 miles of ice below the summit of the Greenland ice sheet. Projections of future melting of the ice sheet are unambiguous: When the ice is gone at the summit, at least 90% of Greenland’s ice will have melted. Results of an ice sheet model show how much of Greenland’s ice sheet survives when the ice is gone from the Camp Century (white dot), GISP2 (red dot) and DYE-3 (black dot) ice...

Wildfire blowups, fire whirls, towering thunderstorms: When fires get large and hot enough, they can actually create their own weather. In these extreme fire situations, firefighters’ ordinary methods to directly control the fire don’t work, and wildfires burn out of control. Firefighters have seen many of these risks in the enormous Park Fire burning near Chico, California, and other wildfires in summer 2024. But how can a fire create weather? Satellite images show how the Park Fire near Chico, Calif., created intense pyrocumulonimbus plumes, visible in white, in July 2024. CSU/CIRA and NOAA I’m an atmospheric scientist who uses data collected by satellites in weather prediction models to better anticipate extreme fire weather phenomena. Satellite data shows fire-produced thunderstorms are much more common than anyone realized just a few years ago. Here’s what’s happ...

Summer 2024’s record heat is creating problems for transportation infrastructure, from roads to rails. New York’s Third Avenue Bridge, which swings open for ship traffic on the Harlem River, was stuck for hours after its metal expanded in the heat and it couldn’t close. Roads have buckled on hot days in several states, including Washington and Wisconsin. Amtrak warned passengers to prepare for heat-related problems hours before a daylong outage between New York and New Jersey; the risks to power lines and rails during high temperatures are a growing source of delays for the train system. It doesn’t help that the worsening heat is hitting a U.S. infrastructure system that’s already in trouble. The American Society of Civil Engineers gave U.S. infrastructure an overall grade of C- in its latest national Infrastructure Report Card, released in 2021. While there has been some improvement – about 7.5% of U.S. bridges were in poor condition, compar...