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The Overspray from Prop 23

On Monday, US energy secretary Steven Chu became the latest high-profile voice against California’s Proposition 23, the statewide initiative to suspend AB 32, the state’s four-year-old climate strategy.

“AB 32 was a good bill and continues to have California in a leadership role in developing clean energy and the efficient use of energy,” Chu told reporters at a dedication in Menlo Park. “From the middle 1970s California played that role and it would just be a terrible setback.”

Last week the trend was given full voice by Mary Nichols, who, as chair of the California Air Resources Board (CARB), is charged with getting AB 32 fully implemented in the next two years, called Prop 23 a “very serious threat,” not just to the core programs of AB 32, but to an array of regulatory programs that support the state’s attack on greenhouse gases. Continue reading

DOE Secretary Opposes Prop 23

In what are believed to be his first public remarks on the subject, US Energy Secretary Steven Chu came out against California’s Proposition 23 today. Chu said passage of the measure, designed to suspend the state’s landmark climate law known as AB 32, would be “a terrible setback.”
Continue reading

Nichols: No Solo Cap-and-Trade

Cap-and-Trade is a lonely business these days. But according to the state’s top regulator in charge of implementing it, California won’t go it alone.

Air Board Chair Mary Nichols, flanked by Google Green Energy Czar Bill Weihl (left) and PG&E Sr. VP Tom Bottorff, at a panel sponsored by the Silicon Valley Leadership Group. (Photo: Craig Miller)

Mary Nichols, who chairs the state’s Air Resources Board, made the remark in a Silicon Valley panel discussion today. The ostensible topic of the event was renewable energy but it turned into a pep rally against Proposition 23, the statewide ballot measure designed to halt California’s comprehensive climate law, AB 32. Nichols was joined on the panel by executives from Google, PG&E and venture capitalist Vinod Khosla, all of whom voiced strong opposition to Prop 23.

When asked about the cap-and-trade provisions of AB 32, Nichols said: “We won’t launch this program without partners to trade with. It doesn’t make sense for an economy even as big as California, to try to do this all by ourselves.” The comment came days after congressional leaders threw in the towel for the summer, on a federal bill to address climate change and energy security. “To get the kind of leverage that you really need to make this program succeed, the US has got to step in,” said Nichols.

California is part of a nascent regional trading pact known as the Western Climate Initiative. But among the seven US states and four Canadian provinces signed on to the WCI, only California, New Mexico and Quebec are prepared to move forward with a working carbon trading market. Others still lack enabling legislation, and Arizona has overtly pulled out of the carbon trading plan, raising the question of how many “partners” California will have, even with WCI in the mix.

“I don’t expect to be faced with this dilemma,” Nichols told me after today’s event, “but if the worst were to happen and none of these states were able to move forward with their own programs, I think we would think long and hard about whether we would actually start enforcing the program, unless and until we were really confident that our  state had the ability to do it in a way that would not put us at a competitive disadvantage.”

Proponents of Prop 23 contend that full implementation of AB 32 will give other states and nations a competitive edge over California, resulting in “leakage” of jobs and businesses to regions with fewer regulations.

The panel, entitled “Electric Bills and Oil Spills: Will California Continue To Be a Clean Energy Leader?” was held on the Google corporate campus in Mountain View.

Poll Shows Support for Climate Law

An expansive new poll on environmental attitudes suggests that despite the recession, Californians are holding fast to their environmental priorities.

Among the findings in the report released this week by the non-partisan Public Policy Institute of California is that support for the state’s climate change strategy remains strong, even in the face of a well-financed campaign against the law known as AB 32. Two-thirds (67%) of the respondents support the 2006 Global Warming Solutions Act, aimed at reducing greenhouse gas emissions in California–about the same level as when PPIC polled the question last year. Continue reading

Another Climate Change Impact: Smog

Los Angeles cloaked in smog shortly after sunrise. (Photo: David McNew/Getty Images)

Air pollution, already a problem for much of central and southern California, will get worse as temperatures warm, according to a new report from scientists at UC Davis and UC Berkeley.

By mid-century, trouble spots like the Central Valley and Los Angeles could experience between six and 30 more days per year when ozone concentrations exceed federal clean-air standards, depending on how much temperatures rise, and assuming that pollutant emissions in the state remain at current levels, the scientists project. Continue reading

When Planes Punch “Holes” in the Sky

This post also appears at Climate Central, a content partner of Climate Watch.

By Michael D. Lemonick

Hole-punch clouds, such as this one, can result when aircraft fly through clouds  containing supercooled water droplets.  Photo credit: Alan Sealls, chief meteorologist, WKRG-TV

Hole-punch clouds such as this one can result when aircraft fly through clouds containing supercooled water droplets. (Photo: Alan Sealls, WKRG-TV)

How did this happen? The crazy-looking cloud formation in the photo above isn’t a still from a sci-fi movie. It’s not “Photoshopped.” It’s quite real.

It’s also totally artificial, which requires a bit of an explanation.

Since at least as early as the 1940s, meteorologists have been noticing formations like this, and it wasn’t long before they figured out that aircraft were probably involved somehow–perhaps by creating a pressure wave as they passed through, or by heating the clouds and evaporating them.

By the 1980s, says Andrew Heymsfield, a scientist with the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, the holes had become more common and the explanation clearer: as planes punch through cloud decks that have particular characteristics, the air is compressed, then expands and cools, just like the coolant in an air conditioner. The cooling forces water droplets to freeze into tiny ice particles; these in turn act as seeds around which raindrops or snowflakes can form. The clouds then “rain out” or “snow out,” leaving a hole in their wake.

That’s the theory, anyway, though the phenomenon also makes great fodder for tabloids. But now Heymsfield has the smoking gun (outlined in a press release from NCAR), so to speak. Back in 2007, he and some colleagues flew their research aircraft through a snow squall west of Denver. They checked later with ground radar and learned that the band of precipitation was oddly shaped–about 20 miles long–but only about 2½ miles wide. It had appeared and disappeared quite abruptly, leaving a couple of inches of snow in its wake. Then they checked the cameras on their plane and discovered a hole in the clouds. Sandwiched between solid cloud decks, it wasn’t visible from the ground.

You might not have seen it from a satellite either; such holes are often hidden entirely. But that’s not the case in this image (below) from space, centered over the Texas-Louisiana border. Nearly all of the spots, big or small, are holes punched by ascending or descending aircraft. Some of the lines are also caused by planes traveling through the clouds at a constant altitude. “You can probably see around 50 of these artifacts in the image,” Heymsfield said.

NASA

This image, captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite, shows shows up to 50 hole-punch features in clouds above Oklahoma, Arkansas, Louisiana, and Texas. (Photo: NASA)

The holes don’t just close up right away, either. “We’ve tracked some of them (by satellite) for up to five hours,” said Heymsfield.

If this phenomenon were just an example of gee-whiz science, the paper Heymsfield and four co-authors published about it in the Bulletin of the American Meteorological Society would be fascinating enough. But it turns out that it has military implications as well. Heymsfield has consulted with Boeing on how to fly jets so as not to leave their calling cards in the sky. “Military aircraft,” he notes, “really don’t want to be visible. (On the day the satellite image was taken) we saw a fantastic trail from a B-52.”

The study also underscores how one of our most natural instincts is simply wrong; that the Earth is so enormous, it seems impossible that human activity could alter the planet in any significant way. Unfortunately, there’s no lack of evidence showing how wrong our instincts can be. Oil spewing into the Gulf, another set of record warm temperatures, and endangered species wherever we look are just a few examples. Holes punched in clouds can now be added to the list of human modifications of the environment around us, even if the results do look like science fiction.

NCAR researcher Andrew Heymsfield discusses his aircraft-induced cloud modification study. (Video: NCAR)

Bay Area Planners Get Greenhouse “Guidelines”

The San Francisco Bay Area is among the first metropolitan areas in the nation to set up local developer guidelines for greenhouse gas (GHG) emissions.

Craig Miller

Photo: Craig Miller

The new rules, passed Wednesday by the Bay Area Air Quality Management District, mean that developers planning anything that will produce GHG emissions above certain thresholds will face an environmental impact review. For “stationary” sources, projected emissions above 10,000 metric tons (tonnes) per year will now trigger an EIR under the California Environmental Quality Act (CEQA). For other, “non-stationary” projects, the trigger is set at 1,100 tons per year or 4.6 tonnes per person affected, such as residents or workers.

The GHG thresholds are coupled with similar triggers for local pollutants such as particulates and for some emissions that play a role in both local air quality and warming, such as nitrous oxides (NOX). Air District spokesman Aaron Richardson couldn’t confirm that the first-in-the-nation status applied to the GHG guidelines, but that it placed the Bay Area “among the first.”

District chief Jack Broadbent said, in a release, that they “provide a blueprint for local agencies to use in making smart development decisions that protect residents from harmful air emissions and greenhouse gases.” Broadbent said the rules will be “especially protective of communities that already have significant air quality concerns.”

Exactly how they’ll be applied is something that even Air District staffers had a tough time explaining. Abby Young, an environmental planner at the District, who worked on the guidelines, explained that 10,000 tonnes per year is a benchmark that might be associated with a major expansion of an oil refinery. She said 1,100 tonnes per year is more or less the level of GHG emissions associated with a typical 50-home suburban housing development, but that vehicle trips in and out of the neighborhood would also be counted toward the threshold. “It’s a very complex, multi-layered thing,” she said.

The complete guidelines are available as a PDF download from the Air District’s website.

What’s Soot Got to Do With It?

By Andrew Freedman, Climate Central

Most of the discussion regarding the highly anticipated Senate energy and climate change legislation, which Senators John Kerry (D-MA) and Joseph Lieberman (I-CT) introduced last week following months of negotiations, has focused on the bill’s provisions pertaining to offshore oil and gas drilling, incentives for renewable energy, and cap on carbon emissions for certain economic sectors.

Although the bill’s carbon dioxide (CO2) emissions reduction targets–an 80 percent emissions cut by 2050 compared to 2005 levels–would yield significant long-term climate benefits, the bill also addresses man-made climate change in the shorter term.

Stack emissions from a bulk freighter in San Francisco Bay. Photo: Craig Miller

Stack emissions from a bulk freighter in San Francisco Bay. Photo: Craig Miller

A little-noticed portion of the bill concerns short-lived air pollutants such as black carbon (otherwise known as soot) and tropospheric ozone. These pollutants disrupt the climate on far shorter timescales than CO2, which scientists consider the most important greenhouse gas and the main villain in the climate change story.

Once emitted by the burning of fossil fuels, the use of solid-fuel cooking stoves or biomass burning, among other sources, black carbon only stays aloft for days to a few weeks before being washed out of the atmosphere by precipitation. This means that once black carbon emissions are reduced, there would be almost immediate climate benefits.

The Kerry-Lieberman bill would direct the US EPA to use its existing authority under the Clean Air Act to reduce black carbon emissions from diesel engines, using devices called diesel particulate filters which trap soot emissions before they escape from a vehicle’s tailpipe.

It would also call upon the EPA to publish a report on black carbon “sources, impacts, and reduction opportunities,” including an examination of how foreign assistance programs could help reduce emissions in other nations. In addition, the bill would establish an inter-agency process to facilitate “fast mitigation strategies” that focus on non-CO2 warming agents. This process would involve agencies such as the EPA and the Energy Department (DOE).

How big a climate player is black carbon?

Black carbon is thought to be a powerful warming agent in many regions, particularly snow and ice-covered areas such as the Himalayas and the Arctic. As its name suggests, black carbon particles are dark in color, and are therefore strong absorbers of incoming solar radiation. They warm the atmosphere and alter cloud characteristics, and when they land on brightly colored snow and ice, they darken the surface, causing a large uptick in the absorption of solar radiation, which hastens melting.

In the Arctic, black carbon contributes to a feedback loop that has helped cause a rapid melting of sea ice cover and drive temperatures upward at nearly twice the rate of the rest of the world. The decade from 1999-2008 was the warmest ten-year period in the Arctic of the past 2,000 years, according to a study published in the journal Science in 2009.

In addition to Arctic warming, black carbon has been shown to alter regional climate patterns such as the Indian monsoon, and human inhalation of soot particles is known to be a major health hazard worldwide.

In recent years numerous scientists, most prominently V. (Ram) Ramanathan of the Scripps Institution of Oceanography and James Hansen of NASA have called for significant cuts in short-lived air pollutants as a way to reduce climate change in the near term, while efforts continue to address CO2 emissions in the long run. Ramanathan’s studies have shown that black carbon may be the second largest contributor to global climate change.

In March testimony before the House Select Committee for Energy Independence and Global Warming, Ramanathan stated that the current global warming effect of black carbon “may be as much as 60 percent” of the CO2 warming effect. He noted, however, that there are significant uncertainties about black carbon’s role in the climate system.

Ramanathan told House lawmakers that reducing black carbon emissions “may provide a possible mechanism for buying time to develop and implement effective steps for reducing CO2 emissions.”

Bill is aligned with recent scientific advice

The Kerry-Lieberman bill’s inclusion of rapid mitigation strategies is consistent with advice contained in a new paper from an interdisciplinary panel of scholars, published on May 11 by the University of Oxford in the UK. The paper argues that non-CO2 drivers of climate change have been overlooked “for reasons of convenience in framing policy” rather than due to scientific concerns, and it presents a vision for an overhaul of climate policy that would include a much more prominent role for addressing emissions of short-lived air pollutants.

“Since action on these non-CO2 ‘forcers’ may have quicker impact and large, immediate primary benefits, we would give them priority, now. In contrast to long and arduous tasks, these can be ‘quick hits’,” the report states.

The bill’s provisions are also consistent with the findings of a scientific panel that examined options to address rapid Arctic climate change. In a 2008 report, the panel strongly endorsed pursuing emissions reductions of black carbon and other short-lived air pollutants. “…Curbing short-lived climate forcing agents, through rapid international action and Arctic nation leadership, may prove to be the best and perhaps only viable strategy for slowing Arctic warming in the time frame of years to a decade,” the report stated.

Considering that the Kerry-Lieberman bill itself faces a highly uncertain future, with significant resistance in both political parties, it may yet take even longer to address what many experts consider to be a ripe, low hanging fruit of the climate challenge. This does not bode well, given the much more difficult work that lies ahead to reduce CO2 and other longer-lasting greenhouse gases.

In April, Molly Samuel reported on the effects of black carbon and snow albedo on the California’s water forecasting efforts.

What’s an Albedo? (And Why You Should Care)

Jeff Dozier approaches the instrument tower on Mammoth Mountain.

Jeff Dozier approaches an instrument tower on Mammoth Mountain. Photo: Molly Samuel

When Jeff Dozier, a hydrologist at UC Santa Barbara, goes to work, he gets to enjoy quite a view. His snow lab is perched halfway up Mammoth Mountain in the central Sierra. We took a gondola to get up there; the other passengers were skiers and snowboarders itching to get out on the freshly fallen snow.

But the instrument platform from which we enjoyed views of the White Mountains is really only half the story. Dozier’s computer lab has much less of a view. In fact, it has no view. It’s buried under the snow, accessible only through what he calls a “Santa Claus entrance” (in the picture above, you can see the entrance–it’s the white tubular “chimney” extending down into the snow from the center of the platform).

The snow lab, operated by both UCSB and the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL), uploads information about the snowpack to a website every fifteen minutes. You can see nearly real-time readings on, among other things, snow depth, temperature, humidity, and radiation.

Dozier in the computer lab. Photo: Molly Samuel

Dozier in the computer lab. Photo: Molly Samuel

Radiation is an important one. Instruments called radiometers are mounted on the tower. Some point up, measuring the radiation coming from the sun; others point down, measuring how much is reflected back to the sky by the snow.

Albedo” is the measurement of how reflective the snow is. Something completely white that reflects all of the sun’s energy has an albedo of one; something black, that absorbs all the energy, is zero. Bright, freshly fallen snow has a high albedo, typically above 0.8.

Even if the term is new to you, albedo is probably a familiar concept. As I reported for KQED’s The California Report this morning, Hans Moosmuller of the University of Nevada’s Desert Research Institute explains it in terms of outfits: on a sunny day, if you wear a black sweater you’ll be warmer than if wear a white one. You may notice it with roofs, too. I grew up in Atlanta, in a house with a black roof. Before my parents got an air conditioner, the upstairs bedrooms were unbearable in the summer. If we’d had a white

These radiometers measure radiation coming from the sun. Photo: Molly Samuel

These radiometers measure radiation coming from the sun. Photo: Molly Samuel

roof, it would have been a little more bearable (though I can’t say it would have helped with Atlanta’s other charming summer attributes, humidity and mosquitoes).

The color sweater you wear has no bearing on the earth’s climate. Roof color could have an effect on a large enough scale. What really matters are the huge swaths of dark and light that cover the globe: ocean and snow.

When warming causes sea ice near the poles to melt faster, areas that had a high albedo (ice is very reflective) become  areas with a very low albedo (the blue ocean absorbs more radiation than forests or plain dirt). Moosmuller says it creates a feedback loop. The more dark spots there are, the more radiation is absorbed. So melting speeds up, and warming increases, exposing even more dark areas, and so on.

Pollution plays an important role that’s coming under increasing scrutiny. Deposits of soot or dust make the snow darker, so it melts faster, exposes more dark ground, and there’s that feedback loop again. In the Himalayas soot, also known as black carbon, from stoves, tailpipes, factories, and fires is having a measurable impact.

In the Rockies, there’s a similar problem caused by dust kicked up from ranches. Tom Painter of the University of Utah says the snow in the Colorado River Basin melts a full month earlier than normal. The difference the dust makes is so drastic, Painter says, that “We’re in an entirely new regime for snow melt…it would be like if we started measuring climate impacts fifty years from now.”

No one has yet done a long-term study on the effects of dust and soot on the Sierra Nevada snow pack. Moosmuller says he’s beginning to look into it now. In the summer, black carbon drifts into the mountains from California’s cities, ports, highways and farms in the Central Valley. Tony Van Curen, in a research project at UC Davis, has found that soot blows over from Asia, too.

There is good news in all of this: Black carbon, unlike most greenhouse gases, lingers in the atmosphere only for a couple of weeks. So reducing emissions could have a relatively quick impact.

Listen to the radio piece.

Icelandic Volcano Chills Travel Plans…But What About the Climate?

This post was contributed by Andrew Freedman of our content partners at Climate Central. Find out why scientists are using volcanoes as a possible model for global climate intervention, on the Climate Watch blog and on KQED’s Forum program.

Eruption of Eyjafjallajökull Volcano, Iceland  (Photo: NASA Earth Observatory)

Eruption of Eyjafjallajökull Volcano, Iceland (Photo: NASA Earth Observatory)


The ongoing eruption of Mt. Eyjafjallajokull in Iceland is disrupting flights across Europe, shutting down some of the busiest airports and aviation corridors in the world. But could it also disrupt the climate system, leading to a temporary cooling trend this summer?

Not likely, according to Rutgers University environmental sciences professor Alan Robock, an expert on how volcanoes alter the composition of the Earth’s atmosphere. According to Robock, the Icelandic eruption hasn’t contributed enough sulfur dioxide to the upper atmosphere to significantly alter the climate.

“From what I’ve seen from the observations so far, there hasn’t been enough put into the atmosphere to have a large climate effect,” he said in a telephone interview.

It is well known that volcanic eruptions can affect the climate. Just ask historians, who can tell you about the “year without a summer” that followed the enormous eruption of Mt. Tambora in Indonesia in 1816. More recently, the 1991 eruption of Mt. Pinatubo in the Philippines, which contributed about 20 megatons of volcanic material to the atmosphere, cooled global average surface temperatures by about one degree Fahrenheit in the year following the eruption.

By vaulting particles of sulfur dioxide and other reflective aerosols high into the stratosphere, volcanic eruptions can reduce the amount of solar radiation reaching the planet’s surface. However, this only results in temporary cooling, since chemical processes and air currents remove the particles over time.

NOAA plot showing a decrease in solar radiation reaching the Earth's surface after major volcanic eruptions

NOAA plot showing a decrease in solar radiation reaching the Earth's surface after major volcanic eruptions

In addition to causing short-term cooling, volcanoes also contribute carbon dioxide (CO2) to the atmosphere, which in the very long-term balances slow CO2 losses from other causes. The volcanic contribution of CO2 to the atmosphere is estimated to be well less than the recent human contribution, on average.

Robock noted that the ash cloud that is canceling flights would not alter the climate, since it will fall out of the air in a matter of days. “What’s dangerous for airplanes is not what causes climate to change,” he said.

The volcano’s climate impacts may also be limited by its high-latitude location, since the air circulation in the upper atmosphere in the high latitudes tends to be more efficient at getting rid of volcanic material, compared to lower latitudes where sulfur dioxide particles from volcanoes can linger for years.

Robock noted that Icelandic eruptions have disrupted climate in the past, such as a long duration event in 1783-4 that cooled temperatures in Europe, catching then US ambassador to France Benjamin Franklin’s attention. According to the National Oceanic and Atmospheric Administration, Franklin was a pioneer in linking a volcanic eruption to climate change.

It’s still possible that this volcano, which is continuing to erupt, may yet send more volcanic material into the upper atmosphere, thereby causing a cooler summer in the northern hemisphere.