Celebrating Earth Day With Sustainable Action Today is Earth Day, when many people around the world are taking time to think about their relationship with the planet and to focus on activities helping to mitigate the existential problems our environment faces. And we will be doing the same: devoting our program to Earth Day stories, ideas, and issues. Sara Kiley Watson, assistant editor at Popular Science in charge of their sustainability coverage, joins Ira to talk about some challenges facing our planet—from air pollution in megacities to the tension between ethanol biofuels and food supplies. She also offers some tips for actions individuals can take to make a small difference on their own, such as improving home energy efficiency even if you’re a renter, reducing the impact of your takeout order, or considering a neighborhood microgrid.   Can The Latest IPCC Report Pave The Way To Better Climate Policy? One of the best resources to understand the state of our climate crisis is the report developed by the United Nations’ Intergovernmental Panel on Climate Change (IPCC), every six to seven years. The most recent installment of the IPCC report, compiled by Working Group III, was released earlier this month. It outlined ambitious steps needed to mitigate some of the worst possible climate futures. It’s increasingly unlikely that we’ll be able to keep the planet from warming by an average of 1.5 degrees Celsius above pre-industrial levels. Yet, the report optimistically focuses on achieving that 1.5 degree benchmark. The report’s recommendations include things like phasing out coal entirely, slashing methane emissions by a third, reducing our carbon output among all sectors of the global economy, and developing new technologies to help us do it. But how do governments make laws to reach these goals? That’s not addressed in the IPCC report. Ira is joined by David Victor, professor of innovation and public policy in the School of Global Policy and Strategy at UC San Diego to discuss the difficulty in developing climate policy solutions and some that seem promising.   Can Carbon Removal Actually Make A Difference In Reducing Emissions? One of the technologies highlighted in the latest IPCC report is carbon removal. Not to be confused with carbon capture, CO2 removal is a process that absorbs CO2 already in the atmosphere and stores it elsewhere. Carbon capture, on the other hand, is removing CO2 from smokestacks, for example, before it gets into the air. CO2 removal technology has some climate scientists worried about pouring money into this new technology, in lieu of cutting back on our reliance on fossil fuels. Joining Ira is Amar Bhardwaj, energy technology policy fellow at the International Energy Agency, to talk about the pros and cons of carbon removal.   Composing A Sound Map Of An Ever-Changing River Annea Lockwood thinks of rivers as “live phenomena” that are constantly changing and shifting. She’s been drawn to the energy that rivers create, and the sound that energy makes, since she first started working with environmental recordings in the 1960s. One of her projects has been to create detailed “river maps” of the Hudson, Danube, and Housatonic rivers. Using stereo microphones and underwater hydrophones, she captures the gentle, powerful sounds of the water, along with the noises of insects, birds, and occasional humans she finds along the way. Lockwood’s composition, “A Sound Map of the Housatonic River”—a decade old, this year—takes listeners on a 150-mile tour, from the headwaters in the Berkshire Mountains of Massachusetts, past sites of toxic PCB contamination, to the Connecticut Audubon sanctuary, where the river spills into Long Island Sound.   Transcripts for each segment will be available the week after the show airs on sciencefriday.com.       Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.