2 posts tagged “global warming”
It would appear that scientists have taken the first step (always the hardest, right?) in identifying why bees worldwide have been dying in massive numbers. It turns out that it isn't global warming, but rather a virus-Deformed Wing Virus.
ScienceDaily (June 29, 2008) — Scientists are one step closer to understanding the recent demise of billions of honey bees after making an important discovery about the transmission of a common bee virus. Deformed wing virus (DWV) is passed between adult bees and to their developing brood by a parasitic mite called Varroa destructor when it feeds.
See also:
Plants & Animals
Virology
Microbes and More
Invasive Species
Bird Flu Research
Microbiology
Pests and Parasites
Reference
Mite
Colostrum
Beekeeping
Vector (biology)
However, research published in the July issue of the Journal of General Virology suggests that the virus does not replicate in Varroa, highlighting the need for further investigation.
Deformed wing virus has been linked to the collapse of honey bee colonies in Britain. In recent years the prevalence of the virus has increased globally in colonies infested with Varroa. It is widely accepted that the virus replicates in the mite and is then transmitted to bees when it bites. However, researchers at Rothamsted Research and the University of Nottingham have found that the virus does not replicate in the mite, suggesting an alternative means of transmission.
"Experiments and field observations have shown that V. destructor is able to transmit several different unrelated honey bee viruses, like acute bee paralysis virus and Kashmir bee virus as well as deformed wing virus," said Professor Teresa Santillan-Galicia from Rothamsted Research. "But we still don't know exactly how these viruses are passed from the mite to the bee."
The researchers wanted to find out whether the virus replicates in the mite and if so where this occurs, to understand how the virus is transmitted. They used a process called immunohistochemistry which involves using antibodies which bind to specific surface proteins, enabling the virus particles to be located. There was no evidence of virus replication within the cells of the mite; the virus was found only in the lumen of the gut, suggesting it was merely eaten.
"The presence of deformed wing virus in large amounts in mite faeces suggests it is picked up during feeding on an infected bee," said Professor Santillan-Galicia. "However, one important question remains -- how is the virus transmitted to bees?"
One possibility is that the mouthparts of the mite could become contaminated with the virus during feeding, but this is an unlikely answer. Varroa mites cannot regurgitate their gut contents as there is a membrane in the oesophagus that acts as a non-return valve, so they could not pass the virus on this way either. Unfortunately, not enough is known about the anatomy of the mite, or their feeding mechanism, to suggest other routes of transmission.
"It is likely that the amount of virus acquired by the mite plays an important role in the interaction between deformed wing virus and the Varroa mite," said Professor Santillan-Galicia. "Full understanding of the interaction between deformed wing virus and the Varroa mite will provide basic information for the future development of more sustainable control strategies against the mite and the virus. Our work provides elements of understanding but further research in this area is needed."
http://www.sciencedaily.com/releases/2008/06/080629191259.htm
It seems impossible to have an honest conversation about global warming. I say this after diligently perusing the British government's huge report released last week by Sir Nicholas Stern, former chief economist of the World Bank and now a high civil servant. The report is a masterpiece of misleading public relations. It foresees dire consequences of global warming isn't curbed: a worldwide depression(with a drop in output up to 20%) and flooding of many coastal cities. Meanwhile, the costs of minimizing these awful outcomes are small: only 1% of world economic output in 2050.
No same person could fail to conclude that we should conquer global warming instantly, if not sooner. Who could disagree? Well, me. Stern's headlined conclusions are intellectual fictions. They're essentially fabrications to justify an aggressive anti-global warming agenda. The danger of that is that we'd end up with the worst of both worlds: a program that harms the economy without much cutting of greenhouse gases.
Let me throw some messy realities on discerns tidy picture. And the global warming debate, there's a big gap between public rhetoric(which verges on hysteria) and public behavior(which indicates indifference). People say they're worried but don't act that way. Greenhouse emissions continue to rise despite many Erinys pledges to control them. Just last week, the United Nations reported that of the foregoing countries and monitors(not including most developing nations), 34 had increased greenhouse emissions from 2000 to 2004. These include most countries committed to reducing emissions under the Kyoto protocol.
Why is this? Here are three reasons.
First: with today's technologies, we don't know how to cut greenhouse gases and politically and economically acceptable ways. The world 1700 or so coal-fired power plants -- big emitters of carbon dioxide, the main greenhouse gas -- her cheap source of electricity. Wholesale cost is $4 to 5 cents a kilowatt hour, says the world resources Institute. By contrast, solar power is five to six times that. Although wind is roughly competitive, it can be used only in selective spots. It now supplies less than 1% of global electricity. Nuclear energy is cost competitive but is stymied by other concerns(safety, proliferation hazards, spent fuel).
Second: in rich democracies, policies that might curb greenhouse gases require politicians and the public to act an exceptionally "enlightened: (read:" unrealistic") ways. They have two accept "pain" now for benefits that won't materialize for decades, probably after they're dead. For example, we could adopt a steep gasoline tax a much tougher fuel economy standards for vehicles. In time, that might limit emissions(personally, I favor this on national security grounds). Absent some crisis, politicians usually won't impose -- and the public one except -- burdens without corresponding benefits.
Third: even if rich countries cut emissions, it will make much difference of us poor countries do likewise -- and so far, they've refused because that might jeopardize their economic growth and poverty reduction efforts. Poor countries are the fastest-growing source of greenhouse emissions, because rapid economic growth requires energy, and present forms of energy produce gases. In 2003, China's carbon dioxide emissions were 78% of the US level. Developing countries, in total, accounted for 37% of greenhouse gases emissions in 2003. By 2050, their share should be 55%, projects the International Energy Agency.
The notion that there's only a modest tension between suppressing greenhouse gases and sustaining economic growth is highly dubious. Stern arrives at his trivial costs -- that 1% of world GDP in 2050 -- by essentially assuming them. His estimates presumed that, with proper policies, technological improvements will automatically reconcile declining emissions with adequate economic growth. This is a heroic leap. To check warming, Stern wants annual emissions 25% below current levels by 2050. The IEA projects that economic growth by 2050 would more than double emissions. At present, we can't bridge that gap.
He is a great distortion and Stearns report involves global warming as effects. No one knows what these might be, because we don't know how much warming might occur, when, where, or how easily people might adapt. Stern's terrific spector distills many of the most terrifying guesses? Including some imagined for the 22nd century, and implies their imminent. The idea is to scare people while reassuring them that policies to avert calamity, it started now, would be fairly easy and inexpensive.
We need more candor. Unless we develop cost-effective technologies to break the link between carbon dioxide emissions in energy use, we can't do much. Anyone serious about global warming must focus on technology -- and not just assume it. Otherwise, our practical choices are all bad: Crossley mandates and controls that harm the economy; across a man facing controls that barely affect greenhouse gases. Or, possibly, both.
