A new report issued this week by the UN’s Intergovernmental Panel On Climate Change paints a troubling picture of the world’s ice and oceans. The ocean effects of climate change, from warming waters to ocean acidification to sea level rise, are already altering the weather, fisheries, and coastal communities. The authors of the report state that the ocean has already taken up more than 90% of the excess heat in the climate system since 1970, the surface is becoming more acidic, and oxygen is being depleted in the top thousand meters of the water column. All those conditions are projected to get worse in the years ahead. Ocean scientist and former NOAA Administrator Jane Lubchenco joins Ira to talk about the risks to the ocean, its effects on the global ecosystem, and how the ocean can also help to blunt some of the worst climate outcomes—if action is taken now.

In his new book, Something Deeply Hidden, quantum physicist Sean Carroll offers a different ending for Schrödinger’s imaginary cat. Carroll ascribes to the “many worlds” interpretation of quantum mechanics, originally proposed by American physicist Hugh Everett in the 1950’s. According to Everett, when you look inside the box you are also in two states at once. Now there are two worlds—one in which you saw the cat alive, and one in which you saw the cat dead. If thinking about this makes your head hurt, you’re not alone. Carroll joins Ira to talk about the “many worlds” interpretation of quantum mechanics, and why he thinks not enough physicists are taking on the challenge of trying to understand it.

Plus: World leaders convened in New York City this week for the United Nations Climate Action Summit. But there wasn’t a whole lot of action at the Climate Action Summit, at least not from the greenhouse-gas-emitting elephants in the room: India, China, and the United States. Umair Irfan, who writes about energy, tech and climate for Vox.com, catches Ira up on how countries around the world are tackling—or ignoring—the climate crisis. 

And Sarah Zhang, staff writer at the Atlantic, tells Ira about NASA's new infrared telescope to detect near-Earth objects and other science headlines in this week's News Roundup.

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