The Science

Latest research from the field and the lab


New Soot Limits Will Challenge Some SoCal Counties

The EPA’s new air quality standards reduce the amount of soot allowed in the air

Soot comes from diesel trucks, industrial emissions and fires.

Two California counties are already behind the eight-ball with the Environmental Protection Agency’s proposed new limits on soot. San Bernardino and Riverside are the only counties in the country that the EPA projects will not be able to adhere to the upper limits of its new range.

Soot has been linked to asthma, heart attacks and strokes and it’s also a culprit in climate change. The nasty stuff, also known as black carbon, comes from smoke from fires, diesel tailpipes and industrial emissions.

The Environmental Protection Agency is proposing an update to its national air quality standards, which seeks to lower the amount of soot in the atmosphere. The new rule would limit the annual exposure to fine particle pollution to between 12-and-13 micrograms per cubic meter. The current standard is 15 micrograms per cubic meter.

The New York Times’ Green blog writes that the EPA had delayed issuing the politically volatile proposal until it was ordered to by a federal court judge. California was one of the states that challenged the delay: Continue reading

Muller on Climate: It’s All About China

Forget California, says the outspoken Berkeley physicist. It’s what China does that matters

Richard Muller

Despite some well-publicized recent conversions on climate matters, Richard Muller’s reputation as a climate skeptic is well earned. In two books, one published and one forthcoming, the UC Berkeley physicist offers counsel on physics and Energy for Future Presidents.

One thing Muller is highly skeptical of is California’s legislated climate strategy, a perspective that he laid out for me in a recent interview at his home in the Berkeley Hils. What matters, he says, is what China does. And little else:

CM: The point here is, and you’ve written about this, is that California can’t save the world in terms of cutting emissions, that no matter what we do, what matters is what China’s doing.

RM: Certainly, California is far too small a part of the global warming problem that anything we do here cannot really help. Even setting an example is something that, I think, is not something we are going to do. But if we can develop an industry that lowers the price of solar cells that lowers the price of wind, that makes nuclear safe, if we can do those things, then that could have a real impact on the future. Continue reading

Mapping the Patchwork of U.S. Warming Trends

The Southwest and Northeast have warmed the most. California is, well, average

They call it “global warming” but where you fall on the warming scale depends a lot on where you live. Not everywhere has warmed the same amount (or at all), and it certainly hasn’t happened at the same rate.

A new analysis from Climate Central, a climate education organization (and content partner with Climate Watch), breaks down the warming trends in the continental U.S., state by state.

Some states show an increase in average temperatures (Minnesota, Maine, Arizona and New Mexico, for instance), and some show nearly none (Florida, Alabama, Georgia). California ends up pretty much in the middle of the pack. Continue reading

New Study Projects More Frequent Fires for the Western U.S.

A new study projects fires in the western U.S. will become more frequent within the next 30 years.

Large fires in the western U.S. — such as those currently raging in Colorado and New Mexico — may be part of a shifting pattern of wildfire risk brought on by climate change, according to a study led by researchers at UC Berkeley.

The study, published Tuesday in the journal Ecosphere, analyzed the results of 16 different global climate change models. The models included variables such as annual precipitation and mean temperature of the warmest month and projected an increase in the frequency of fires across the majority of North America and much of Europe within the next 30 years.

“In the long run, we found what most fear — increasing fire activity across large parts of the planet,” said study lead author Max Moritz, a fire specialist with UC Berkeley, in a press release. “But the speed and extent to which some of these changes may happen is surprising.” Continue reading

400 ppm: A Milestone that Means Everything, and Nothing

For the first time in history, the atmosphere’s concentration of CO2 has topped 400 ppm

Commentary by Michael D. Lemonick

CO2 levels have been climbing since the Industrial Revolution.

I’m not big on taking note of milestones. They’re artificial, and usually meaningless, but people get all worked up about them anyway. I don’t like to stay up late on New Year’s Eve, for example, because Dec. 31 is a purely arbitrary date. Nothing real actually begins the next day, but we all pretend otherwise. I have similar feelings about the first day of spring, the temperature reaching 100° as opposed to 99° and all sorts of other magic-sounding dates and numbers that don’t have any real significance.

But since no law says I have to be consistent, I’m going to take note of a milestone that happened some time in the past couple of months, and which was reported last week by NOAA. For the first time in recorded history, and almost certainly for much longer than that, the atmosphere’s concentration of carbon dioxide, or CO2, has nipped above 400 parts per million in at least one part of the world. Monitoring stations in Alaska, northern Europe, and Asia have all noted readings above that level during this past spring.

In one sense, this isn’t all that important. There’s no meaningful difference between 399 ppm and 400, and the current world average is more like 393. Even in the Arctic, scientists know the CO2 level will drop back below 400 this summer, as trees in the Northern Hemisphere suck carbon dioxide back out of the atmosphere (you can see the annual ups and downs as trees start growing in the spring and go into hibernation in the fall). We won’t get to a world average of 400 for several years yet.
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The Far-Reaching Effects of Smog: Is It a Driver of Drought?

Black carbon and tropospheric ozone, two pollutants typically associated with urban smog, may be key drivers in the advance of the northern tropics.

The northern tropics are on a march toward the pole. Over the last thirty years, the warm, moist belt around the equator has expanded by between 2-and-8 degrees northward.

When the phenomenon was first described five years ago, it was thought to be fueled primarily by carbon dioxide emissions. But a report, published recently by University of California at Riverside researchers in the journal Nature, has proposed a new driver of the expanding tropics: soot and ozone pollution generated largely by wood burning and diesel combustion in the rapidly developing nations of Southeast Asia. Continue reading

Can Better Batteries Shrink California’s Carbon Footprint?

Jump-starting the Bay Area’s battery research could yield answers beyond 2020

By Thibault Worth

Tommy Conry loading a lithium coin cell for testing at LBNL's battery lab.

We’ve reported extensively about AB 32, California’s 2006 greenhouse gas reductions law that calls for 1990-level carbon emissions by 2020.

But what happens to carbon reduction efforts beyond that date?

A less publicized, yet more aggressive 2050 target calls for slashing carbon emissions to 80% below 1990 levels by mid-century.  That goal was established by an Executive Order by Governor Arnold Schwarzenegger in 2005. Achieving such an ambitious target will require a range of initiatives, including building better batteries.

AB 32 calls for 33% of California’s energy to come from renewable sources by 2020. But while solar and wind energy produce zero carbon, they also fluctuate. The current solution is to balance those fluctuations with fast-ramping natural gas-fired power plants. And they produce carbon aplenty. Continue reading

A Little Lake Reveals Clues About Past Megadroughts

Scientists stumbled on Fallen Leaf Lake and the ancient trees under its surface

Scientists found important climate clues hidden away under Fallen Leaf Lake, just south of Lake Tahoe.

Graham Kent wasn’t researching megadroughts when he and a team of scientists began studying Fallen Leaf Lake, just south of Lake Tahoe. They were mapping faults. The little lake is a good place to study West Tahoe Fault, which cuts right through it.

“Little did we know it was a natural lab for droughts, as well,” Kent, director of the Nevada Seismological Lab at University of Nevada, Reno, told me over the phone. “So what started out as a seismic hazard endeavor became both a seismic hazard and climate study.”

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Getting Serious About the “Other” Greenhouse Gases

Are we too focused on CO2?

While carbon dioxide reductions are at the heart of efforts in California to curb greenhouse gas emissions, state air regulators were reminded in a hearing on Thursday not to overlook a number of other “short-lived” greenhouse pollutants in meeting targets outlined under AB 32, the state’s Global Warming Solutions Act.

A panel of noted scientists was on hand, several from California universities and research labs, to discuss the effects of black carbon, methane and hydrofluourocarbons on regional and global climate. Short-lived pollutants such as these are estimated to comprise more than a third of overall global climate warming emissions. (Carbon dioxide, by comparison, makes up 56% of total global greenhouse emissions.) Continue reading

A Visual Deep Dive into California’s Delta

Ambitious mapping & data effort accompanies KQED multimedia series

"Deadlocked Delta" is a multilayered look at where much of California's water comes from.

If, like most Californians, you’re a bit fuzzy on why the Sacramento-San Joaquin Delta matters to you, take a tour through the impressive new online resource from KQED’s science unit, the San Francisco Estuary Institute, and Stanford’s Bill Lane Center for the American West.

“California’s Deadlocked Delta” is more than a data trove for water geeks, it’s a visually pleasing deep dive into the single most important piece of California’s persistent water puzzle. It provides some eye-opening glimpses of how this critical intersection for the state’s freshwater supply has changed over generations. Continue reading