Making sense of this week’s climate change news

What’s with all these climate protests?

The street demonstration in Manhattan on Sunday was timed to today’s United Nation’s summit on climate change. It was believed to be the single biggest climate protest — ever. More than 300,000 marched in New York that day, including students, monks, actor Mark Ruffalo, New York Mayor Bill de Blasio and U.N. Secretary General Ban Ki-moon. And, naturally, former Vice President Al Gore.

But that was merely one of 2,800 rallies in some 160 countries calling for action on climate change. In Bordeaux, a child wore a gas mask with a sign reading, “Mommy, can I go play outside?” On a beach in Australia, people “saluted” Prime Minister Tony Abbott by sticking their heads in the sand and their butts in the air.

And in New York on Monday, hundreds of protesters, including one in a polar bear costume and another dressed as Captain Planet, marched through New York City’s financial district dressed in blue to symbolize rising floodwaters and staged a sit-in attempted to “block Wall Street.” Dozens were arrested. Their message to Wall Street, to stop financing the oil industry, reflected a new focus on fossil fuel “divestments.”

Divestments? What does that mean?

Divestment, or divestiture, refers to the process of selling an asset. In this context, it means a push for big companies and individuals to sever ties with investments in oil and coal by selling stocks. What started as a move on university campuses became bigger news on Monday when the Rockefellers, heirs to the oil dynasty that originated with Standard Oil, announced a plan to divest a large holding of fossil fuel stocks, citing concerns about rising emissions due to climate change. The Rockefeller Brothers Fund will join a $50 billion campaign to divest investments linked to fossil fuels. Participants also include businesses, religious groups, even cities like Santa Monica, California, and Seattle.

Gwen Ifill discussed this campaign with Jenna Nicholas of Divest-Invest Philanthropy on last night’s show:

A campaign of “divestments” will be presented at today’s meeting by Al Gore.

But climate change is not a new problem. Why is this happening now?

Today’s meeting is in part preparation for a meeting in December in Lima, Peru, and a bigger conference in December 2015 in Paris. In advance of these conferences, this summit puts pressure on countries at the national level to focus attention on climate change.

“What I take away from this is that Ban Ki-moon and the U.S. are interested in giving the issue high profile in advance and in preparation for the ultimate meeting in Paris in 2015,” said Michael Oppenheimer, a professor at Princeton University and member of the Intergovernmental Panel on Climate Change.

Will any of this really move the ball forward or is it just another rehash of the same debate?

It’s not all old news. President Obama announced today that the U.S. government will offer vulnerable populations abroad new scientific tools to “strengthen their climate resilience.” The government will also be required to factor climate change into money spent overseas to help poorer countries. Watch his speech here:

Also new at this meeting is a deadline to curb greenhouse gas emissions by halting deforestation. The United States, Canada and the European Union are among the 32 countries signing on, the Associated Press Reports. But Brazil, home to huge swaths of rainforest, has said no to endorsing the initiative.

Still, many obstacles to progress remain. Among them, cost, partisan gridlock, the persistence of the problem and “deep divisions between industrialized nations and developing countries,” wrote Robert N. Stavins in an opinion piece in the New York Times. Stavins is an IPCC author and director of the environmental economics program at the Harvard Kennedy School. But market-based solutions to reduce emissions combined with creative leadership could hold promise, he concludes.

If history is any indicator, it’s unlikely that any global treaty will be reached. But smaller-scale negotiations between countries that result in reducing carbon emissions could be an alternative, along with an informal “pledge and review” process that relies on public exposure to pressure countries into progress, Oppenheimer said. “Countries would be shamed in not doing what they said they would do, but they would not be penalized,” he said.

In the meantime, language on the meeting’s website is ambitious, challenging leaders to “bring bold announcements and actions to the summit that will reduce emissions, strengthen climate resilience, and mobilize political will for a meaningful legal agreement in 2015.”

That seems like a lot of PR mumbo jumbo. Remind me, why this is such a big deal?

Simply, it’s part of a push to do more to reduce harmful greenhouse gas emissions. Reports out this month showed levels of carbon dioxide in the atmosphere reaching record highs, a reduced ability by oceans and plant life to soak up that carbon, and birds like the cerulean warbler and the bald eagle rapidly losing habitat.

Climate change is occurring, and it’s “extremely likely” that it’s human-caused, according to the most recent report by the Intergovernmental Panel on Climate Change.

Stavins described it this way:

The world is now on track to more than double current greenhouse gas concentrations in the atmosphere by the end of the century. This would push up average global temperatures by three to eight degrees Celsius and could mean the disappearance of glaciers, droughts in the mid-to-low latitudes, decreased crop productivity, increased sea levels and flooding, vanishing islands and coastal wetlands, greater storm frequency and intensity, the risk of species extinction and a significant spread of infectious disease.”

Who is at the climate summit?

President Obama joins 120 world leaders at the summit, along with celebrities like Leonardo DiCaprio, who has been crowned a “UN Messenger of Peace” by Ban Ki-moon.

And it’s not just environment leaders. U.S. Treasury Secretary Jacob Lew, for example, who has called climate change “one of the most important challenges of our time” is attending.

But just as important is who’s not there: Chinese president Xi Jinping and India’s Prime Minister Narendra Modi. This is notable because China and India, along with the United States, are the world’s top emitters. The countries will be represented by other diplomats, but some have called their absence a snub.

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