Global warming

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,...

You probably have been hearing phrases like “climate crisis,” “climate emergency” or “climate justice” more often lately as people try to get across the urgent risks and consequences of climate change. The danger is real, but is using this language actually persuasive? It turns out that Americans are more familiar with – and more concerned about – climate change and global warming than they are about climate crisis, climate emergency or climate justice, according to a recent survey we conducted with a nationally representative sample of 5,137 Americans. Moreover, we found no evidence that the alternative terms increased people’s sense of urgency, willingness to support climate-friendly policies or willingness to act. The familiar terms – climate change and global warming – did at least as well, and sometimes better, than climate crisis and climate emergency in eliciting concern, perceived urgency and willingness...

The North Atlantic Ocean has been running a fever for months, with surface temperatures at or near record highs. But cooling along the equator in both the Atlantic and eastern Pacific may finally be starting to bring some relief, particularly for vulnerable coral reef ecosystems. This cooling comes from two climate phenomena with similar names: La Niña, which forms in the tropical Pacific, and the less well-known Atlantic Niña. Both can affect the Atlantic hurricane season. While La Niña tends to bring conditions ideal for Atlantic hurricanes, the less powerful Atlantic Niña has the potential to reduce some of the hurricane risk. Cooling in the tropical Atlantic along the equator is a sign an Atlantic Niña may be forming. NOAA Climate.gov We’re ocean and atmospheric scientists who study this type of climate phenomenon. It’s rare to see both Niñas at the same...

You’ve probably heard people say, “It’s not the heat, it’s the humidity.” There’s a lot of truth to that phrase, and it’s important to understand it as summer temperatures rise. Humidity doesn’t just make you feel sticky and uncomfortable – it also creates extra dangerous conditions on hot days. Together, too much heat and humidity can make you sick. And in severe cases, it can cause your body to shut down. Meteorologists talk about the risk of heat and humidity using the heat index, but it can be confusing. I’m a risk communication researcher. Here’s what you need to know about the heat index and some better ways meteorologists can talk about the risks of extreme heat. Outdoor workers can be at high risk of heat illnesses. Robert Gauthier/Los Angeles Times via Getty Images What is the heat index, and how is it measured? Heat index...

Dozens of wildfires are burning across Canada in May 2024 and sending unhealthy smoke blowing into the northern U.S. again. At the same time, the southeastern U.S. is getting smoke from Mexico, where drought conditions have been fueling fires. Last year, Canada’s record 2023 wildfire season introduced millions of Americans across the Midwest and northeastern states to the health hazards of wildfire smoke, with air quality alerts that reached levels never seen there before. Professional baseball games were postponed and the skies in New York City turned orange with haze, at times exposing millions of people to the worst air quality in the world. In some regions, the smoke hung on for days. The pressing question on many people’s minds: “Is this the new normal?” From our perspective as air quality scientists, we think the answer is likely “yes.” Global warming means more fires Hotter, drier conditions, coupled with dry grasses and underbrush...

Climate change is threatening America’s water infrastructure as intensifying storms deluge communities and droughts dry up freshwater supplies in regions that aren’t prepared. Severe storms that swept through the South in April 2024 illustrated some of the risks: In New Orleans, rain fell much faster as the city’s pumps could remove it. A water line broke during the storm near Hattiesburg, Mississippi. Other communities faced power outages and advisories to boil water for safety before using it. We study infrastructure resilience and sustainability and see a crisis growing, particularly in the U.S. Southeast, where aging water supply systems and stormwater infrastructure are leaving more communities at risk as weather becomes more extreme. Neighborhoods across the New Orleans area flooded on April 10 as the region’s pumps couldn’t keep up with the rainfall. Credit: Reed Timmer. To find the best solutions and b...

Earth Day is April 22, and climate activists around the world are planning rallies and other events to draw attention to the growing threats posed by climate change. Many of these demonstrations will focus on what humanity can do to stop fueling the damage. But while activists are amplifying the dire findings from scientists, you’ll likely see fossil fuel supporters attacking them on social media and TV. It’s easy to get caught up in the myths about climate activism, particularly in today’s polarized political environment. So, let’s take a moment to explore the truth about three of the big myths being told about climate activism and the climate movement today. Myth 1: Climate activists are just young people The media tends to focus most of its attention on young people in the climate movement, including those inspired by Greta Thunberg’s school strikes for climate, the international Fridays for Future, or the Sunrise Movement, which focuses on U....