Climate change: What we know, what we're doing

For this week's Climate Cast, Kerri Miller and meteorologist Paul Huttner take a deep dive into the issue of climate change with a full hour on one of the world's biggest concerns. Today's show highlights not only how our lives are affected by climate change, but what people are doing about it.

BLAMING HUMANS FOR OUR WARMING PLANET

In 1995, climate scientist Ben Santer first brought up the notion that humans were partially to blame for a warming planet. His views on climate change, backed by stacks of data, have gone from being in the extreme minority to the near-universally accepted majority.

"The warming we have seen in these many different aspects of the climate system — the ocean, the land surface, the ice, the atmosphere, water vapor, pressure patterns, circulation patterns — these changes cannot be purely explained by natural causation," Santer said. "You need a substantial human influence in order to best explain the observed changes we've seen."

Santer said the frequency of extreme weather events has helped people understand the impact of climate change.

"What really matters for the world, and your listeners, and for me and my family and kids and grandkids, is the behavior of extreme events," he said. "In the last eight years, we've experienced Katrina, we've experienced Sandy, we've experienced Haiyan. In eight years, three events that are staggering in terms of their implications for humanity, in terms of the devastation, the loss of life. I think, as scientists, we urgently need to understand how we are changing the likelihood of those types of events. And indeed I think that those kinds of indicators, those are things that we really should be paying attention to."

WHAT SANDY TELLS US ABOUT FUTURE EXTREME WEATHER

Climate Central got an up-close and personal look at extreme weather, thanks to Superstorm Sandy. It has been tracking the rising sea level and what it means to cities around the country.

Andrew Freedman, senior science writer for Climate Central, has been looking at the sea levels in New York.

"Between about 1900 and when Sandy hit, we had a sea level rise of about a foot in lower Manhattan," he said. "Part of that was due to natural settling of the land and man-made global warming, which is melting the ice and heating the oceans and therefore rising sea levels. So what this really does is amplifies the destructive power of any storm whether it's a Nor'easter in New England or a hurricane hitting Florida or elsewhere on the East Coast. You end up with more intense, more damaging storm surges than you would have had previously from the same storm strength."

Freedman said scientists estimate that the rise in sea level exposed about 50,000 more people to flooding from Sandy than had the sea-level rise not occurred.

"New York City has been finding through the panel that they've set up that is you're drastically expanding what they call your Zone A, which is that dreaded zone that you're going to be forced to evacuate in that storm situation, and in many cases, where you have to buy flood insurance," he said.

The biggest potential victim is the state of Florida, Freedman said. More than 2,000 square miles of the state's land is less than three feet above high tide.

"Now in terms of property value in that area, that's $156 billion in value and 300,000 homes that sit within three feet or less of the high tide line," he said. "And Florida historically has been a magnet, if you will, for hurricanes, and when you get hurricanes hitting that area you get storm surges and storm surges riding on top of sea levels that are already higher due to climate change."

While cities like New York consider water barriers for future hurricanes, inland cities are creating resiliency plans for climate change too.

"They're also being done by inland cities such as Chicago, which is trying to deal with getting a handle on its heat wave situation, and Denver and St. Louis and other cities," Freedman said. "So even inland locations will have to deal with and are already dealing with impacts of extreme weather events, some of which are tied in part to climate change."

SCIENCE MUSEUM'S EFFORT TO REDUCE ENERGY CONSUMPTION

The Science Museum of Minnesota is leading the way in a scientific concept known as exergy in large buildings.

Pat Hamilton, director of global change initiatives at the Science Museum, is working on a way to retrofit America's large buildings for more efficient heating and cooling. The change leads to dramatic cuts in both energy costs and greenhouse gas emissions.

"If we could improve the energy performance of buildings by 40 or 50 percent, then you're seeing a huge reduction in greenhouse gas emissions that are due to the energy consumption of buildings," he said.

The system captures waste heat and reuses it inside the building.

Hamilton's "exergy retrofit" team created reverse heat engines, which are about the size of a big minivan.

Facilities manager Tom Carlson sees the museum saving big dollars. The cost for the heating, cooling and electrical service for the Science Museum is about $1.1 million per year. The savings with the retrofit will be an estimated $250,000 to $270,000.

Hamilton likes the potential return on "exergy" investment. He estimates the Science Museum will spend $840,000 for the exergy retrofit. That's a payback of less than three and a half years.

STUDYING CLIMATE CHANGE IN THE GLACIERS OF ALASKA

To get to his work site, Eric Osterberg, assistant professor in Dartmouth University's department of earth sciences, spends two weeks traveling into the mountains of Alaska.

Osterberg studies high-altitude climate change. This summer he was part of a team of scientists that went to Alaska's Denali National Park to drill ice cores from glaciers.

"You've got some of the most beautiful mountains around you that you'll see anywhere in the world," he said. "You've got Mt. Hunter, it just imposes over base camp. It's this almost vertical rock wall that is directly above base camp. And that's what some people actually climb. It's basically a vertical rock wall with ice mixed in, and that's why it's so difficult. And then behind you, you've got Mt. McKinley, Denali, sort of imposing over everybody. And then there's another mountain, Mt. Foracker, that's just off to the side. So, you're surrounded by this unbelievable, breathtaking scenery, and you're just plopped down there in a ski plane."

WHY WE SHOULD ALL BE TREE HUGGERS

Craig Bowron, physician and writer, explains why we should all hug a tree. In an essay published by Huffington Post, Bowron reminds us that we all require oxygen to survive. In an average day, a human breathes in a total of 1.5 to 2 pounds of oxygen.

The climate change battle is in need of fresh branding, Bowron says:

In any war it's critical to carefully brand your opponent, and in the war over climate change and what to do about it, the "climate deniers" have won the branding battle. They've been tagged with the rather harmless singular name, "denier," while those fighting climate change are often referred to as "environmental advocates," "nature lovers," "outdoor enthusiasts," "Earth activists," or the more pejorative "Earth freak" or "tree hugger." All of those descriptors evoke a certain fluffiness of character, a pathetic softness, as if these were the people who cried when they watched Bambi. These are the ethereal, ungrounded, low-GNP birdwatchers who walk off into meadows and stare at things. These are the sissy Whole Foods vegans, the lily-white pacifists watching nature shows on PBS.

This kind of branding trivializes the battle over climate change as an alarmist ploy from the "greenies," who care more about spotted owls and rare Amazonian frogs than they do their fellow humans. It gives the appearance that the struggle isn't about the science or its implications, but only about a way of life. It's the Audubon Society against the NFL. You stare at your birds, I'll stare at my flat-screen TV.

THE INTERNATIONAL POLITICS OF CLIMATE CHANGE

In 1985 the world was seemingly taken by surprise as a hole opened up in the ozone layer over Antarctica. Richard Benedick, an ambassador in the Reagan administration, was asked to help negotiate a deal in Montreal in 1987 to curb chlorofluorocarbons (CFCs) that caused the hole.

So Benedick became one of the key players in the negotiations, and they worked. But it's a very different political landscape today.

"I call these meetings medieval trade fairs," he said. "They were one week, sometimes two weeks long. I went to a number of them in Marrakesh and Morocco. And in Amsterdam. It was just a lot of fun. There were the cultural events and the native dancers. And there's some drama because the NGOs will try to make a riot or demonstration, then the police were there. I've been through all of those. It was like a circus."

Benedick sees more pomp and circumstance than negotiations at meetings like the recently concluded Warsaw Climate Change Conference. And with thousands of people from nearly 200 countries, how can you really expect them to change anything?

"It's very, very hard to craft a treaty," he said. "We're talking about a treaty that has to be implemented by different countries, by different agencies within the country. It just has not worked. And that's why, interestingly, now we're involved in this controversy over geo-engineering, because the scientists are very worried. But once you do that, you don't know what's going to happen. Theoretically, it could cause flooding. It could cause drought. You just don't know. You're playing around with something on a planetary basis, and it could be something like the sorcerer's apprentice."

GEO-ENGINEERING THE ENVIRONMENT

Physicist David Keith has been watching the planet warm and trying to change global policy on climate change for two decades. One of his partial solutions: geo-engineer the environment by shooting tiny droplets of sulfur into the stratosphere. The theory is that the droplets would deflect some of the sun's heat and cool the planet. The problem is that this is still theoretical, but Keith thinks it's time to include it in the conversation.

Seeding the stratosphere with sulfur droplets sounds scary, and it is. Keith will be the first to tell you about the potential problems that might arise with such a procedure. But he also believes we're past the point of using carbon emission cutbacks as the cure.

"The disadvantage of it is that you can have loss of ozone, loss of stratospheric ozone," he said. "There are other health consequences. The advantage of it is because we've seen large volcanoes put very large quantities of sulfur in the stratosphere, [and] we have some sense of the 'unknown unknowns,' which is what people, sensibly, are scared about, are potentially controlled and understood."

According to Keith, the technology already exists to seed the sky and cool the planet. Small, Gulfstream business jets with modified wings could be flown up into the stratosphere.

"If you wanted to start in 2020 and cut the rate of global warming roughly in half, you need to start with a small number — say two or three modified business jets that would release sulfuric acid vapor," he said. "Because the amount of CO2 keeps rising — hopefully we'll stop that — each year you'd need to put a little bit more in. So you might start by putting 10,000 tons of sulfur, then maybe by 2050, you'd need to put something like a million tons of sulfur, which might involve a fleet of 40 or 50 specially designed aircraft. The gee-whiz aspects of technology are not that important. The really hard questions are whether we should do it, what the risks are, what the tradeoffs are."