Sugar cane ethanol cools climate when it replaces cattle pasture

Converting cattle pasture and cropland in Brazil to sugar cane helps cool local climate reports research published in Nature Climate Change. 

Scientists with the Carnegie Institutions’s Department of Global Ecology at Stanford University and the University of Montana analyzed temperature, reflectivity, and evapotranspiration from satellite data across 733,000 square miles—an area larger than the state of Alaska. They found converting from natural cerrado grassland vegetation to crop/pasture on average triggered warming of 2.79 °F (1.55 °C), but that subsequent conversion to sugarcane, cooled the surrounding air by an average of 1.67 °F (0.93°C). 

"We found that shifting from natural vegetation to crops or pasture results in local warming because the plants give off less beneficial water. But the bamboo-like sugarcane is more reflective and gives off more water—much like the natural vegetation," said Carnegie's Scott Loarie, lead author of the research. "It’s a potential win-win for the climate—using sugarcane to power vehicles reduces carbon emissions, while growing it lowers the local air temperature." 

"The beneficial effects are contingent on the fact sugarcane is grown on areas previously occupied by crops or pastureland, and not in areas converted from natural vegetation," stated a press release from the Carnegie Institution. "It is also important that other crops and pastureland do not move to natural vegetation areas, which would contribute to deforestation." 

The findings suggest that Brazil's sugar cane ethanol industry, which powers a quarter of the country's automobile fleet, has even more benefits than previously believed. Sugar cane ethanol has significantly lower carbon dioxide emissions than conventional gasoline. 

The research also indicates the importance in accounting for non-fossil fuel-based climate impacts. 

"It’s becoming increasingly clear that direct climate effects on local climate from land-use decisions constitute significant impacts that need to be considered core elements of human-caused climate change," said coauthor Greg Asner, also of the Carnegie Institution. 

Cornell Gas Study Stirs Heated Debate

More researchers and policy analysts have had a chance to digest a new study analyzing the climate impacts of unconventional natural gas development, published this week in the journal Climatic Change Letters. Many of the reactions echo earlier complaints that some of the methane leak data on which the study’s conclusions were based are thin (a fact that the authors, including the lead author, Robert Howarth of Cornell University, conceded).

Others critics continue to suggest that the authors unduly amplified the greenhouse gas footprint of unconventional gas development by measuring the global warming potential of leaked methane over a 20-year time frame, rather than the 100 years more commonly used by the Intergovernmental Panel on Climate Change.

That choice, the critics say, jacks up methane’s global warming footprint unnecessarily, allowing the authors to reach their controversial conclusion: that unconventional natural gas development is worse than coal.

Indeed, Melanie Kenderdine, the executive director of the M.I.T. Energy Initiative, told CNBC on Tuesday that “there are major scientific organizations that think we should actually extend that hundred-year period, not shorten it.”

Dan Lashof, the director of the Climate Center at the Natural Resources Defense Council, writing at the group’s Switchboard blog, took a more balanced view. He suggested that “there is no one right answer for the appropriate time horizon to consider, so the I.P.C.C. publishes [global warming potential] values for 20, 100 and 500 years.”

He continued:

For methane the I.P.C.C. values from its most recent report are 72, 25, and 7.6, respectively. Howarth does not consider the 500 year G.W.P. and relies on a more recent study by Shindell et al. that suggests that the indirect warming impact of methane (through chemical interactions in the atmosphere) could raise its G.W.P. to 105 over 20 years and 33 over 100 years. While these higher figures were produced by well respected researchers, they have not yet been subject to the level of review and scrutiny conducted by the I.P.C.C. for its estimates. Moreover, while I can see an argument for using a time horizon shorter than 100 years, I personally believe that the 20-year G.W.P. is too short a period to be appropriate for policy analysis because it discounts the future too heavily. I calculate that over a 50-year period, the G.W.P. of methane would be in the range of 42-56, based on the I.P.C.C. and the Shindell et al. analyses.”

Mr. Howarth, responding to Ms. Kenderdine’s comments, said that the majority of peer-reviewed papers on the greenhouse gas footprint of conventional gas have tended to consider both the long- and short-term time scales. He also said he was unaware of any “major scientific organizations” supporting and extension of the hundred-year period in this context.

“This flies in the face of the I.P.C.C. 2007 report, their most recent, as well as all climate change science of which I am aware,” he said.

Meanwhile, a novel critique came Friday from Michael A. Levi, the David M. Rubenstein Senior Fellow for Energy and Environment at the Council on Foreign Relations. Mr. Levi repeats some of the concerns raised by others, but he also adds this one:

Howarth’s gas-to-coal comparisons are all done on a per energy unit basis. That means that he compares the amount of emissions involved in producing a gigajoule of coal with the amount involved in producing a gigajoule of gas. (Don’t worry if you don’t know what a gigajoule is – it doesn’t really matter.) Here’s the thing: modern gas power generation technology is a lot more efficient than modern coal generation, so a gigajoule of gas produces a lot more electricity than a gigajoule of coal. The per kWh comparison is the correct one, but Howarth doesn’t do it. This is an unforgivable methodological flaw; correcting for it strongly tilts Howarth’s calculations back toward gas, even if you accept everything else he says.

I also reached out to Mr. Howarth to see if he had any response to this. Here’s what he had to say:

The per kWh is the “correct” analysis only if the question is simply one of generating electricity from natural gas vs. coal.

However, 70 percent of natural gas in the U.S. is used for purposes other than for generating electricity, such as home and commercial heating, hot water heating, transportation, and industrial energy uses such as making nitrogen fertilizer and distilling ethanol. For these purposes, natural gas has no efficiency advantage over using other fossil fuels (oil or coal). And for these uses, it would be inappropriate to use a per Kwh basis (Kwh is used only for electricity).

For the 30 percent of natural gas used to generate electricity, there is indeed an efficiency advantage for natural gas over coal. We state this explicitly in the paper, in section 6: “Our analysis does not consider the efficiency of final use. If fuels are used to generate electricity, natural gas gains some advantage over coal because of greater efficiencies of generation (see Electronic Supplemental Materials). However, this does not greatly affect our overall conclusion: the GHG footprint of shale gas approaches or exceeds coal even when used to generate electricity (Table in Electronic Supplemental Materials). Further, shale-gas is promoted for other uses, including as a heating and transportation fuel, where there is little evidence that efficiencies are superior to diesel oil.”

In the on-line only materials, we run through the calculation from electricity generation. …

Our analysis was designed to show the importance of considering methane as part of the greenhouse gas footprint of shale gas, which had never been done before. And we designed it so that other scientists could examine it in the context for any end use, as Hughes has done for electricity. We believe the singular focus on electricity is inappropriate, given how gas is actually used, and how it is being promoted for other uses. …

One other detail: Kwh is not a standard international metric unit, and therefore is not approved for use in a science journal such as the one in which we published. The joule is the approved unit, and the one we used. But that is a technical detail: the important point is the extent to which one focuses on electricity vs. other uses of energy.

Mr. Levi, in an e-mail Monday morning, replied thusly:

I’m glad to see that we agree that the per kWh approach is the “correct” one for discussions of electricity generation from gas vs. coal. But this isn’t nearly as marginal as Howarth seems to believe. Gas vs. coal is the key debate to which the paper appears to attempt to speak. The fact that 70 percent of natural gas is used for things like home heating is beside the point — no one is weighing gas against the option of shoveling coal into the boiler in their basement. Howarth also claims to have addressed the issue in the paper. But it is inconsistent for him to claim that, with the adjustment, “the GHG footprint of shale gas approaches or exceeds coal” while also saying that it “does not greatly affect our overall conclusion” — after all, the paper’s overall conclusion is that gas is unequivocally worse than coal, which is qualitatively different.

Stand by for more points and counterpoints. They are almost certain to come.

The Koch Brothers and Climate Science, Redux

Last year, Greenpeace, the environmental group, accused the brothers Charles and David Koch of a stealth campaign to attack climate science, setting off extensive media scrutiny of the Kochs and their company, Koch Industries. (A Koch subsidiary is a major oil refiner.) Now Greenpeace is out with an update.

The new report largely adds detail, from the advocacy group’s perspective, to some previously disclosed activities of the company and various groups financed by its owners and employees. For instance, the report highlights donations from Koch interests to the unsuccessful attempt last year to get voters to roll back California’s ambitious clean-energy policy. Similarly, the report lays out Greenpeace’s take on the battle over the Regional Greenhouse Gas Initiative, a compact of states in the Mid-Atlantic and Northeast that seeks to limit greenhouse gases.

Greenpeace now has a whole section of its Web site devoted to tracking the Koch interests. Koch Industries itself, under heavy media scrutiny since last year’s report, has started a blog to challenge its critics and publicize demands the company makes for corrections to articles, as well as to lay out the Koch brothers’ positions on various issues.

Killer Grizzly

If you think global warming is some distant threat, come visit Yellowstone, our most beloved national park. Acres of trees are dying, trout runs are disappearing, and starving bears are attacking campers. It’s an ecosystem in collapse, and things are only getting worse.

by Paul Solotaroff // photographs by Christopher LaMarca

Before that heartbreaking night at the end of July, she was a ghost bear tramping the backwoods shade, a scared specter at her wit’s end. She and her three cubs, all woefully thin and eking out a diet from grass and shoots, were so unwell that they wore their winter coats through the full, high heat of summer. In a lean year for grizzlies, they stood last in line, going without a solid meal of deer or elk or the staple of Yellowstone’s bears, whitebark pine seeds. Those seeds, rich and fleshy, had grown for centuries on the crowns of the staunchest trees in North America: gnarled, obdurate pines that survived 50-below winters and laughed off killing winds on western peaks. Nothing could slay those trees, neither fire nor ice, until the region started warming around 1980. Now 80 percent of the Rockies’ whitebark pine groves stand dead or dying in ghost-gray swaths, and the bears who ate their fruit and kept out of harm’s way have bumbled down the hills in search of food. Among their number was the sow with three cubs and teats running dry of milk. With winter two months off, she had to somehow bulk up fast or watch her yearlings starve.

To her credit, she hadn’t become a “problem bear,” the park officials’ term for hundreds of hungry grizzlies who venture into town prowling for food. Though Yellowstone’s 600 bears aren’t confined to the park itself — they’re given free run of the greater ecosystem, an area that stretches from central Wyoming to the forests of northern Montana — there simply wasn’t enough alternative food to see all of them through the summer. And while full-grown males have the brawn and bravado to venture off the range in search of meat, a mother grizzly rarely leaves the safety of her turf, lest a wolf pack or another bear kill her cubs. Timidity had its virtues: She wasn’t one of the 80 or so bears shot last year while picking apples off a tree or nosing through trash in someone’s backyard, or given a lethal injection by U.S. Fish and Wildlife vets for grazing on the bluegrass near a school.

Six weeks before, the first shoe dropped. On June 17, an adult male bear (or boar, as they’re called by biologists) killed a veteran hiker who had the wretched luck to cross his path. Erwin Evert, a botanist and and retired science teacher, had spent most of his career studying Yellowstone’s flora and had just brought out his life’s masterwork, the first comprehensive catalog of plants in the area in more than a hundred years. On his daily hike near Wyoming’s Kitty Creek, the easternmost of the park’s gateways, he wandered into a copse where a team of federal researchers had trapped and sedated a bear. Alas, they hadn’t posted warning signs or waited until the boar was sufficiently roused to pad back into the brush. Dazed and in pain (he’d been darted three times with a chemical cognate of PCP, then had blood, teeth, and hair pulled for study reasons), the bear bit Evert through the skull and skittered off; he was shot two days later by marksmen in a chopper who tracked his radio signal. There hadn’t been a bear-caused fatality in the park in 24 years, though given the grim developments of the prior decade — a 10-year run of extreme drought and heat, and a glut of famished grizzlies — the screw was bound to turn. On July 28, it turned again, and this time it wasn’t about human error or the caprices of nature’s law. This time, it was a taste of things to come.

Link Below:

http://www.mensjournal.com/the-ghost-park

Fossil-fuel will dominate even in 2030: ExxonMobil

 

There is bad news for those determined to tackle global warming. No matter how desperately the world wants to reduce carbon emissions through a cut in fossil-fuel consumption, it seems an inescapable fact that such fuels will continue dominating global energy demand 20 years from now.

NY Times: Studies Say Natural Gas Has Its Own Environmental Problems

Natural gas, with its reputation as a linchpin in the effort to wean the nation off dirtier fossil fuels and reduce global warming, may not be as clean over all as its proponents say.

Even as natural gas production in the United States increases and Washington gives it a warm embrace as a crucial component of America’s energy future, two coming studies try to poke holes in the clean-and-green reputation of natural gas. They suggest that the rush to develop the nation’s vast, unconventional sources of natural gas is logistically impractical and likely to do more to heat up the planet than mining and burning coal.
The problem, the studies suggest, is that planet-warming methane, the chief component of natural gas, is escaping into the atmosphere in far larger quantities than previously thought, with as much as 7.9 percent of it puffing out from shale gas wells, intentionally vented or flared, or seeping from loose pipe fittings along gas distribution lines. This offsets natural gas’s most important advantage as an energy source: it burns cleaner than other fossil fuels and releases lower carbon dioxide emissions.
“The old dogma of natural gas being better than coal in terms of greenhouse gas emissions gets stated over and over without qualification,” said Robert Howarth, a professor of ecology and environmental biology at Cornell University and the lead author of one of the studies. Mr. Howarth said his analysis, which looked specifically at methane leakage rates in unconventional shale gas development, was among the first of its kind and that much more research was needed.

Read more.

New York set to be big loser as sea levels rise

New York is a major loser and Reykjavik a winner from new forecasts of sea level rise in different regions.

The Intergovernmental Panel on Climate Change (IPCC) said in 2007 that sea levels would rise at least 28cm (1ft) by the year 2100.

But this is a global average; and now a Dutch team has made what appears to be the first attempt to model all the factors leading to regional variations.

Other researchers say the IPCC's figure is likely to be a huge under-estimate.

Whatever the global figure turns out to be, there will be regional differences.

Ocean currents and differences in the temperature and salinity of seawater are among the factors that mean sea level currently varies by up a metre across the oceans - this does not include short-term changes due to tides or winds.