Originally published on Mon April 22, 2013 1:51 pm
Now in its 43rd year, Earth Day has become an international day dedicated to promoting environmental awareness and action. Lester Brown, president of the Earth Policy Institute, explains what's changed, as concern about climate change and green energy have come to the forefront of the movement.
Barbara Natterson-Horowitz is a cardiac consultant for the Los Angeles Zoo, a member of the zoo's Medical Advisory Board and director of imaging at the UCLA Cardiac Arrhythmia Center.
Dr. Barbara Natterson-Horowitz, a cardiologist at the UCLA Medical Center, coined the term "zoobiquity" to describe the idea of looking to animals and the doctors who care for them to better understand human health. Veterinary medicine had not been on her radar at all until about 10 years ago. That's when she was asked to join the medical advisory board for the Los Angeles Zoo and she began hearing about "congestive heart failure in a gorilla or leukemia in a rhinoceros or breast cancer in a tiger or a lion."
Ken Caldeira of the Carnegie Institution for Science takes a water sample during his experiment on part of the Great Barrier Reef. The water is slightly pink because his team is using a dye to trace an acid-neutralizing chemical as it flows across the reef.
Credit Richard Harris / NPR
Ken Caldeira, a researcher with the Carnegie Institution for Science, pilots an aluminum skiff filled with equipment for his experiment on the reef. He is trying to figure out whether corals would grow faster if he neutralized human-induced changes in the ocean's acid balance.
Credit Richard Harris / NPR
Caldeira pours fluorescein dye over the coral to determine which direction the current is flowing. This spectacular dye is also used in medical diagnosis and is considered harmless for the reef.
Credit Richard Harris / NPR
Tubes snake back to a floating tank (the yellow object in the background), which is attached to a skiff anchored just off the reef. The tank contains antacid and some red dye.
Credit Courtesy of Lilian Caldeira
The world's oceans are 30 percent more acidic than they were before the industrial revolution because carbon dioxide from cars and power plants dissolves in ocean water and turns into carbonic acid. That threatens the health of the world's coral reefs.
Credit Richard Harris / NPR
The antacid mixture is pumped over the reef during the hourlong experiment. Caldeira hopes it will neutralize the water and help the coral grow.
Credit Richard Harris / NPR
Field assistant Benjamin Cox keeps track of water samples as they are drawn from the edge of the reef. The samples will be analyzed in a chemistry lab back on One Tree Island.
Credit Richard Harris / NPR
The sun sets at One Tree Island. The research Caldeira's team is doing might help save small patches of coral reefs, but it would be impossible to scale up a chemical treatment to protect whole reefs from increasing ocean acidity.
Credit Courtesy of Lilian Caldeira
Researchers from the Carnegie Institution for Science spent a month at a remote research outpost — One Tree Island, at the southern end of the Great Barrier Reef — to study how changing ocean acidity is affecting coral reefs.
Credit Richard Harris / NPR
Members of the research team fend for themselves in a communal kitchen (while fending off persistent ants) before heading out for a challenging day on the reef.
Most scientists find a topic that interests them and keep digging deeper and deeper into the details. But Ken Caldeira takes the opposite approach in search for solutions to climate change. He goes after the big questions, and leaves the details to others.
The Antares rocket lifts off from the launchpad at the NASA facility on Wallops Island Va., Sunday, beginning a test mission that has now been deemed a success. The Orbital Sciences Corp. rocket will eventually deliver supplies to the International Space Station.
Keep your eye on the sky Sunday evening; the Lyrid meteor shower is expected to peak. It's the first meteor shower of the spring season.
The Lyrid shower is caused by Earth passing through the orbit of a comet known as Thatcher, though the comet itself hasn't been seen since 1861. Dust particles from the comet will be seen as flashes of light as they burn up in our atmosphere.
Workers at a cooperative farm near Shanghai scatter fertilizer across fields of winter wheat. Image from the May issue of National Geographic magazine.
U.S. hospitals have been urged to be on the lookout for symptoms of bird flu among patients who have recently traveled to China, where a new strain of the virus has killed 17 people and infected more than 70.
