Tim McDonnell joined Climate Desk after stints at Mother Jones and Sierra magazine. He remains a cheerful guy despite covering climate change all the time. Originally from Tucson, Tim loves tortillas and epic walks.
As we reported this week, some of the world's richest nations are lagging behind on their climate protection pledges. Most often, these commitments follow the formula: "We aim to reduce greenhouse gas emissions X percent below year Y levels by year Z." It seems like a straightforward proposition, but have you ever wondered where those numbers come from? The answer is a scientific concept known as the carbon budget, and like a teenager with her first credit card, we're well on our way to blowing right through it.
In the video above, Kelly Levin, a climate policy expert at the World Resources Institute, explains what our carbon budget is, how much we've already "spent," and why it matters.
Back in 2009, delegates to the UN climate summit in Copenhagen agreed that in order to avoid the worst potential impacts of climate change, global temperature rise should be limited to 2 degrees Celsius above preindustrial levels. For their report this fall, scientists on the UN's Intergovernmental Panel on Climate Change looked at how emissions of carbon dioxide and other greenhouse gases have warmed the planet since the Industrial Revolution, and extrapolated how much more we could emit before breaking the Copenhagen limit, the same way you might draft a budget to keep your checking account balance above zero.
Children stand amidst the rubble of Cebu, Philippines, after Typhoon Haiyan.
Aid agencies are still digging through rubble in the Philippines in the wake of Super Typhoon Haiyan, which was just one of many record-smashing oceanic storms to spring up in the last decade. Insurance adjusters have already pegged Haiyan's price tag alone—counting damage to homes, businesses, and farms—at $14.5 billion. Today, as politicians and policy wonks dive into a second week of UN climate talks in Warsaw, the Philippines' lead delegate has called for developed nations whose industrial emissions drive climate change to foot the bill for disasters like this. It could be one hell of a bill: Natural disasters altogether have cost the world $3.8 trillion since 1980, according to a new report from the World Bank.
Using data from Munich Re, the world's largest reinsurance (insurance for insurers) agency, World Bank analysts found that 74 percent of that cost arose from weather-related disasters like hurricanes and droughts. They also found, as the chart below shows, that annual costs are on the rise, from around $50 billion a year in the 1980s to $200 billion a year today, thanks to a rising number of disasters and growing economic development:
Deforestation is a tricky problem to nail down. We know forests are shrinking, but knowing exactly where and by how much often means compiling locally reported data that can be shoddy, incomplete, or outdated, according to University of Maryland geographer Matthew Hansen. Better data would be an invaluable tool for resource managers looking to preserve trees, and for climate scientists who want to crunch how much carbon they can store, Hansen realized. So he set about to create the most high-resolution map of global forests ever made, partnering with Google Earth to process some 650,000 images taken by NASA satellites over the last decade.
The result, published today in Science, is a stunning series of time-lapse maps, along with an interactive mapping tool, that reveal the Earth lost about 888,000 square miles of forest between 2000 and 2012, roughly the area of the US east of the Mississippi River. The loss, which was most dramatic in the tropics, was primarily due to logging, urban development, strip mining, and other human impacts, Hansen said, but the figure also includes loss from fires, earthquakes, and other natural disasters. The maps are accurate to 11-square-mile units, close enough to see logging roads and individuals stands of trees, which gave the researchers an unprecedented look at the complete extent and rate of deforestation on a global and hyper-local scale.
In the exclusive video above, Hansen takes us on a tour of his new maps and the startling situation they reveal.
Producing super-detailed maps like these would have been impossible without Google's massive computer power; Hansen estimated his own computer would have taken 15 years to process all the images, while Google's servers churned them out in a few days.
The data could be used to track the impact of forest protection policies, and hold a microscope to the forested areas most at risk.
"It's a big leap forward in terms of a set of facts, a set of observations on what this dynamic is," Hansen said.
One of the next steps, Hansen said, is to use the data to gauge exactly what this deforestation means for climate change. Trees are one of the largest "sinks" for carbon dioxide; previous studies suggest forests absorb a third of the carbon released by burning fossil fuels.
Michael Gerrard, the Center's director, said his team combed through all 50 reports to see how accurately and comprehensively climate change was taken into consideration, if at all, and grouped them into four ranked categories:
No discussion of climate change or inaccurate discussion of climate change.
Minimal mention of climate change related issues.
Accurate but limited discussion of climate change and/or brief discussion with acknowledgement of need for future inclusion.
Thorough discussion of climate change impacts on hazards and climate adaptation actions.
While FEMA itself acknowledged this summer that climate change could increase areas at risk from flooding by 45 percent overt the next century, states are not required to discuss climate change in their mitigation plans. The Columbia analysis didn't take into account climate planning outside the scope of the mitigation plans, like state-level greenhouse gas limits or renewable energy incentives. And as my colleague Kate Sheppard reported, some government officials have avoided using climate science terminology even in plans that implicitly address climate risks; states that didn't use terms like "climate change" and "global warming" in their mitigation plans were docked points in Columbia's ranking algorithm.
Gerrard said he wasn't surprised to find more attention paid to climate change in coastal states like Alaska and New York that are closest to the front lines. But he was surprised to find that a plurality of states landed in the least-prepared category, suggesting a need, he said, for better communication of non-coastal risks like drought and heat waves.
"We had hoped that more of the states would have dealt with [climate change] in a more forthright way," he said.
Climate deniers like to point to the so-called global warming "hiatus" as evidence that humans aren't changing the climate. But according a new study, exactly the opposite is true: The recent slowdown in global temperature increases is partially the result of one of the few successful international crackdowns on greenhouse gases.
Back in 1988, more than 40 countries, including the US, signed the Montreal Protocol, an agreement to phase out the use of ozone-depleting gases like chlorofluorocarbons (today the Protocol has nearly 200 signatories). According to the EPA, CFC emissions are down 90 percent since the Protocol, a drop that the agency calls "one of the largest reductions to date in global greenhouse gas emissions." That's a blessing for the ozone layer, but also for the climate. CFCs are a potent heat-trapping gas, and a new analysis published today in Nature Geoscience finds that slashing them has been a major driver of the much-discussed slowdown in global warming.
"The recent decrease in warming, presented by global warming skeptics as proof that humankind cannot affect the climate system, is shown to have a direct human origin."
Without the Protocol, environmental economist Francisco Estrada of the Universidad Nacional Autónoma de México reports, global temperatures today would be about a tenth of a degree Celsius higher than they are. That's roughly an eighth of the total warming documented since 1880.
Estrada and his co-authors compared global temperature and greenhouse gas emissions records over the last century and found that breaks in the steady upward march of both coincided closely. At times when emissions leveled off or dropped, like during the Great Depression, the trend was mirrored in temperatures; likewise for when emissions climbed.
"With these breaks, what's interesting is that when they're common that's pretty indicative of causation," said Pierre Perron, a Boston University economist who developed the custom-built statistical tests used in the study.
The findings put a new spin on investigation into the cause of the recent "hiatus." Scientists have suggested that several temporary natural phenomena, including the deep ocean sucking up more heat, are responsible for this slowdown. Estrada says his findings show that a recent reduction in heat-trapping CFCs as a result of the Montreal Protocol has also played an important role.
"Paradoxically, the recent decrease in warming, presented by global warming skeptics as proof that humankind cannot affect the climate system, is shown to have a direct human origin," Estrada writes in the study.