Global Cooling, Global Warming
Aug 8 at 2:02pm by Aileen
Researchers from Oregon State University and other institutions have published an article in the journal Science that they say puts to rest a long scientific debate on the causes of periodic ice ages in the history of our planet. The conclusion? Earth Wobbles.
The last major ice age reached its peak about 26,000 years ago, held steady for about 7,000 years, then began melting 19,000 years ago. The melting was caused by an increase in solar radiation, the researchers say, and not by carbon dioxide’s “greenhouse” effect, or any changes in ocean temperatures. These mechanisms have been cited recently by some scientists trying to understand what appears to be happening now with the increase in global temperatures termed “Global Warming” and said to be caused primarily by pollution from human activities.
The researchers analyzed 6,000 dates and locations of ice sheets to define when they started to melt. This confirmed a theory developed more than fifty years ago that held small but definable changes in Earth’s rotation as the trigger for both the accumulation of ice and its melting cycle. Putting that together with changes in the Earth’s axis and rotation going back 50 million years, they found that the gravitational influences of the larger planets – primarily Saturn and Jupiter – leads to predictable cycles.
Right about now, the scientists say, we should be changing from an interglacial period toward conditions that will ultimately lead to another ice age. That is, if human contributions to Global Warming don’t thwart the process. Meanwhile, a close look at plans to mitigate global warming with ‘Geoengineering’ suggests that such plans may well do more harm than good.
Research presented at a symposium at the Ecological Society of America’s annual meeting concludes that geoengineering is potentially dangerous, and that the risks outweigh the benefits. Plans such as limited nuclear detonations and subsequent fires to release lots of carbon into the atmosphere, seeding the atmosphere with light colored sulfur particles to mimic gigantic volcanic eruptions, and seeding the oceans with iron to increase carbon uptake all come with side-effects that could be disastrous, ecologists say.
Indeed, if we are starting to ‘wobble’ to the gravitational tune of our giant planetary neighbors toward another ice age, taking big efforts to cool the planet right now could actually speed up the process! Perhaps we should put off the big projects until we know more about all this, eh?
Popularity: 57% [?]
Forest Management vs. Carbon Sequestration
Jul 13 at 3:03pm by Aileen
If you or someone you know has chosen to live in or surrounded by forest – or just maintains a vacation cabin in such a setting – you are probably aware of the threat that wildfires present to property in those settings. And as the population has spread in many states out into more forested regions, many states and the federal government have undertaken forest fire prevention efforts to lessen the impact of such fires.
In the Pacific Northwest and elsewhere plans for fire prevention have included the idea of fuel reduction. This means thinning the forests and eliminating much of the understory growth. A recent study from Oregon State University sought to quantify the carbon sequestration and CO2 impacts of such a plan, and how these things affect global climate change.
Forest Fire Prevention Efforts Could Lessen Carbon Sequestration, Add to Global Warming details the issues and the report. The report’s authors came to a somewhat surprising conclusion:
“If fuel reduction treatments are effective in reducing fire severities in the western hamlock, Douglas-fir forests of the west Cascades and the western hemlock, Sitka spruce forests of the Coast Range, it will come at the cost of long-term carbon storage, even if harvested material are used as biofuels.”
The idea of using the plants and trees removed from the forest to lessen fire severity as raw material for biofuels was previously thought to offset the carbon sequestration costs of taking those trees. But it turns out that the production of biofuels isn’t very fossil fuel efficient and that the amount of energy returned doesn’t add up to the amount of energy used.
The kind of material at issue that would be harvested from the forests doesn’t produce good biodiesel fuel, which is better produced from oil-crops and such. Woody trees and shrubs are best used to make ethanol, but that process isn’t yet efficient enough to offset itself.
Another recent OSU study concluded that if the old forests of the Pacific Northwest were left alone or managed exclusively to promote carbon sequestration, they could double the amount of sequestration in many areas, even triple it in some other areas.
Bottom line then appears to be that if you build your house or vacation cabin in the old growth forests of the PNW, you shouldn’t expect to have the state or feds manage that forest so your property isn’t at risk from forest fires. Still, to many people the time spent in such abundant natural surroundings is worth the risk.
Popularity: 59% [?]
White Roofs to Mitigate Global Warming?
Jun 15 at 9:09pm by Aileen
The Washington Post reported on a recent talk by Energy Secretary Steven Chu that white rooftops may help slow global warming by reflecting sunlight instead of absorbing it. Perhaps even better, white roofs cut energy consumption for cooling by an almost equal percentage.
Climate scientists say the reflective properties of white are so much greater than gray, black, green or any other color, that simply by putting white roofs on enough buildings and houses we could buy the time we need to make other necessary changes to combat global warming. In fact, the energy savings alone on air conditioning caused the state of California to begin requiring that most new flat-roofed buildings have reflective roofs, and retail giant Walmart has installed them on 75% of its stores in the United States. Even Washington, D.C. has gone so far as to require than new flat roofs be covered either in vegetation or have reflective roofs for the energy savings alone.
The Environmental Protection Agency offers good information and cost analysis for reflective roofing products on its Energy Star website with multiple links to manufacturers, resources and data.
Secretary Chu emphasized in his speech that the Lawrence Berkeley National Laboratory conducted research demonstrating that if just 63% of the roofs in 100 large cities and tropical/temperate areas worldwide were white, the effect would provide the same climate benefits as taking all the cars in the world off the road for a full decade. That’s considerable, and definitely worth the effort.
Popularity: 31% [?]
About those Mammoths? …Never Mind.
Jan 27 at 8:08pm by Aileen
On the fifth of this month I posted Supernovae, Comets and Holey Mammoth Tusks, about a recently-developed theory with apparently lots and lots of confirming evidence, that purported to demonstrate the mass extinction of North American megafauna – wooly mammoths, giant bison, saber-tooth cats, etc. – was the result of effects from a supernova explosion 250 light years from earth, and a 10-kilometer wide comet produced that hit or exploded just above Chicago nearly 13,000 years ago.
Well, this week researchers from the University of Bristol say they have disproven that theory, by examining charcoal and pollen records for the great fires the comet must have caused. Their results, they say, provide no evidence of continental-scale fires. Though they do say their examination of this material dated between 15,000 and 10,000 years ago, somehow establishes that an increase in large-scale wildfires all over the world during the past 10 years is attributable to global warming.
Ah, well. So much for grand theories about great and sudden climate change in past ages, as well as ongoing disagreements about climate change in the current age. Perhaps what is best to be learned from this back and forth of disagreements about evidence and what it means is to take the pronouncements of various groups of scientists with a grain of salt, for their conclusions are often so short-lived as to not even make it past the publication schedule of two successive issues of the same journal!
Eventually, maybe, they’ll work it all out.
And while we’re here looking at research from different sources that can end up with entirely different conclusions, check out a new project site from Creative Commons – ScienceCommons. Making the Web work for science, to develop technologies to make research, accumulated data and materials easier to find and use. I’ll be reporting on this again in the near future, so stay tuned!
Links:
Supernovae, Comets and Holey Mammoth Tusks
North American Comet Impact Theory Disproved
ScienceCommonsPopularity: 37% [?]
Update on Wind and Grid Issues
Dec 17 at 7:07pm by Aileen
As the economy slips ever farther down the black hole of imaginary values and criminal greed, the looming necessity for using this crossroads of history to re-make our energy future has moved the issues up on the To-Do list. America’s automakers are lining up, hats in hand, to obtain enough funding to keep their (union) workers employed, and the funds they want may come attached to serious strings that require more gas-efficient cars, hybrids, flex-fuel and even new lines of plug-in electric cars to help get us off our addiction to other nations’ oil.
Which then begs questions about what sources of electrical energy we need to develop that do not spew greenhouse gases into the air, leave us with millions of tons of toxic or radioactive industrial waste, and cause serious detrimental health effects (and death) to the population. Following on the issue of our choices for future development is the antiquated state of our electrical grid, which is both inefficient and dangerously likely to fail altogether without much trouble.
Fact is, energy use conservation could make a more serious dent in our consumption without doing anything at all. This is what happened this past summer when gasoline prices climbed to around $5 per gallon, and diesel prices became inverted. Millions of people limited their driving, pooled for shopping excursions, and stayed home instead of driving long distances for vacation. Petroleum usage plummeted, which informs us that we don’t really have to use as much as we do. Changing light bulbs and turning off lights and appliances and turning down the thermostat can save quite a bit of our generation capacity too, but that will of course jump when we have to charge our cars at night.
Popularity: 42% [?]
John McCain Finally Answers the Science Questions
Sep 15 at 3:03pm by Aileen
As the Excitement of the national party conventions fades and we move into the debate phase, Republican Presidential candidate John McCain has submitted his responses to the 14 questions posed by the crew at Science Debate 2008. Democrat Barack Obama submitted his responses previously, and the SD08 website now has the two candidate’s responses listed side by side for easy comparison.It would be great to see some of these questions come up in the debates, so that follow-ups to the positions could be explored.
Popularity: 34% [?]
Barack Obama Answers the Science Questions
Aug 30 at 11:11pm by Aileen
Democratic Presidential candidate Barack Obama has submitted his Answers to the Top 14 Science Questions facing America. Drawing on the expertise of a squadron of science, economic, foreign policy and educational advisors that includes several committed Nobel Laureates, many will be happy to get the religious and political ideology out of the way and really start addressing these issues.Please go to the ScienceDebate 2008 website, take a hard look at Obama’s answers for our future, and don’t forget to drop the crew a dime (or ten) on your way out. These folks have been hard at it since November of last year, and have gathered some very impressive institutional support. The future is important to all of us – and our children – and the future needs the very best science we can possibly field to meet it head-on.
Popularity: 45% [?]
Where Have All the Salmon Gone?
May 5 at 4:04pm by Aileen
A declaration of commercial fishery failure by Commerce Secretary Carlos Gutierrez has paved the way for Congress to allot funds for alleviating financial hardship among the West Coast’s commercial Chinook salmon fishing industry off California and Oregon. The crisis has been building steadily every year since 2000, culminating in this latest action – the commercial salmon fishing industry has essentially been shut down.
National Oceanographic and Atmospheric Administration [NOAA] researchers suggest that changes in ocean conditions – possibly due to global warming – are to blame, along with loss of freshwater habitat for salmon spawning, a chronic problem.
There will be some coho salmon fishing allowed off the coast of Washington and northern Oregon, but there will be financial hardship in that industry as well due to strict limits. This crisis has been building for years, attempts along the way to mitigate it have proven to exacerbate the situation, such as the introduction of farmed salmon. Fish stock collapses in traditionally abundant fisheries off both coasts and elsewhere in the world bode ill for the seafood component of the human food supply, just as the worldwide food crisis heats up around the world for staple crops like corn and wheat and rice.
We could be beyond a tipping point right now, and things could get a bit more than just ‘interesting’ over the next months. Will science be able to come to the rescue, or will it remain helpless to mitigate the collapse of world food supplies? Stay tuned…
Links:
“Fishery Failure” Declared for West Coast Salmon Fishery
Hatchery Controversy Takes on New Significance as Wild Chinook Populations Crash
Escaped Farmed Salmon Infiltrate Fitter Wild Populations
Dramatic Declines in Wild Salmon Populations Linked to Farmed SalmonPopularity: 21% [?]
Giant Antarctic Sea Creatures!
Mar 24 at 7:07pm by Aileen
Photo by John Mitchell – Antarctic explorers Sadie Mills and Niki Davey holding giant Macroptychaster sea stars.
During an 8-week survey expedition to the Antarctic Ross Sea south of New Zealand, researchers discovered a host of giant sea creatures. In addition to the starfish pictured above, there were “…huge worms, giant crustaceans and sea spiders the size of dinner plates,” according to Dr. Martin Riddle, leader of the Aurora Australis expedition.
The expedition collected some 30,000 specimens – including jellyfish with 12-foot tentacles – hundreds of which may be new to science. Riddle attributed the large size of polar species to cold water temperatures, few predators, high oxygen levels and longevity.
The expedition was a project of the International Polar Year program, where experts from 23 countries expect to mount 10 more expeditions to examine Antarctic sea life. The specimens collected so far will take a couple of years to fully categorize. It is hoped that the project’s cataloguing of Antarctic ocean biodiversity will help scientists monitor the impact of environmental change, as Antarctic waters should be among the first to respond to ocean acidification caused by rising atmospheric carbon dioxide levels.
Popularity: 9% [?]
10 Earth Science Questions for the 21st Century
Mar 15 at 5:05pm by Aileen
The National Research Council has identified and reported on Ten Questions that will shape 21st century earth science. Some may be a little surprised that these questions are still unanswered, having been told in no uncertain terms in science classes in the last century that science already had definitive answers to questions like how the earth and other planets in our solar system formed. Live and learn. Here’s a bare list of the identified questions…
1. How did earth and other planets form?
Scientists still do not know enough about how our planet got its elements to understand its evolution, or why other planets in our system are very different.2. What happened during the first 500 million years?
Current scientific belief is that another planet collided with ours during the late formation stage, creating the moon and melting this planet all the way to its core. Yet unknown is how (and when) the Earth developed its atmosphere and oceans.3. How did life begin?
Scientists hope to obtain evidence from rocks and minerals, as well as investigations of Mars and other members of our system.Popularity: 31% [?]
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