gallery some images of clouds to enjoy, assembled with recent reports about the ostensible topic at Wit's End - ozone and its effects on vegetation.
This squidworm, a species barely 4 inches in length, was just recently discovered in the Celebes Sea of South East Asia, in deep water between Indonesia and the Philippines. Teuthidodrilus samae is purportedly an elegant swimmer, with oars fluttering like dominos. How thoughtlessly we trample on such translucent rarity, a microcosm of the fragility and delicacy of all Nature's creations.
reports: "World Dangerously Close to Food Crisis, UN says"
Global grain production will tumble by 63 million metric tons this year, or 2 percent over all, mainly because of weather-related calamities like the Russian heat wave and the floods in Pakistan, the United Nations estimates in its most recent reporton the world food supply. The United Nations had previously projected that grain yields would grow 1.2 percent this year.
Wow. So a 3.2% decline in projected production is enough to predict a food crisis? How about this message:
"Dear Gail, It is generally recognized that 10 to 20% of potential crop yield is lost each year because of ozone...the stunting of plants even by "acceptable" levels of ozone is quite amazing."
- Tom Sharkey, Professor and Chair, Dept. of Biochem. Mol. Biol., Michigan State U...email dated August 2, 2009
some research from 2007, which postulates that the indirect effect of ozone (suppressing plant growth and carbon sink) will be a GREATER effect on climate change than direct radiative forcing - which may seem rather oblique...
"The evolution of the Earth’s climate over the twenty-first century depends on the rate at which anthropogenic carbon dioxide emissions are removed from the atmosphere by the ocean and land carbon cycles. Coupled climate–carbon cycle models suggest that global warming will act to limit the land-carbon sink, but these first generation models neglected the impacts of changing atmospheric chemistry."
"Emissions associated with fossil fuel and biomass burning have acted to approximately double the global mean tropospheric ozone concentration, and further increases are expected over the twenty-first century. Tropospheric ozone is known to damage plants, reducing plant primary productivity and crop yields, yet increasing atmospheric carbon dioxide concentrations are thought to stimulate plant primary productivity. Increased carbon dioxide and ozone levels can both lead to stomatal closure, which reduces the uptake of either gas, and in turn limits the damaging effect of ozone and the carbon dioxide fertilization of photosynthesis."
"Here we estimate the impact of projected changes in ozone levels on the land-carbon sink, using a global land carbon cycle model modified to include the effect of ozone deposition on photosynthesis and to account for interactions between ozone and carbon dioxide through stomatal closure.
For a range of sensitivity parameters based on manipulative field experiments, we find a significant suppression of the global land-carbon sink as increases in ozone concentrations affect plant productivity. In consequence, more carbon dioxide accumulates in the atmosphere.
We suggest that the resulting indirect radiative forcing by ozone effects on plants could contribute more to global warming than the direct radiative forcing due to tropospheric ozone increases."
"Rising Ozone Levels Likely Contributor to Global Food Crisis"
|These pictures of fallen trees were forwarded from Massachusetts by Roger and Susan Shamel of GWEN.|
"New research has indicated that rising background levels of ozone in the atmosphere are a likely contributor to the global food crisis, since ozone has been shown to damage plants and reduce yields of important crop, including soybeans and wheat.
The research was conducted by William Manning of the University of Massachusetts Amherst in the US.
'Plants are much more sensitive to ozone than people, and a slight increase in exposure can have a large impact on their productivity,' said Manning.
'The new ozone standard set by the US EPA in March 2008 is based on protecting human health, and may not be strict enough to protect plants,' he added.
According to Manning, emission controls on cars have been successful in reducing short periods of high ozone levels called peaks, but average concentrations of ozone in the atmosphere throughout the year, called the background level, is increasing as polluted air masses from Asia travel to the US and then on to Europe.
Background levels are now between 20 and 45 parts per billion in Europe and the United States, and are expected to increase to between 42 and 84 parts per billion by 2100.
Plants can limit ozone damage for short periods of time by reducing the size of pores on their leaves called stomata. This reduces the uptake of ozone, but also carbon dioxide, which is used as the plants make food through the process of photosynthesis.
Chronic exposure results in reduced photosynthesis, plant growth and yields.
In the long term, leaf injury occurs when the amount of ozone taken in exceeds the leaf's capacity to provide antioxidants to counter its effects.
Manning was recently part of a team of researchers studying how ozone levels in the Yangtze Delta affect the growth of oilseed rape, a member of the cabbage family that produces one-third of the vegetable oil used in China.
By growing the plants in chambers that controlled the ozone environment, the team showed that exposure to elevated ozone reduced the size and weight, or biomass, of the plants by 10 to 20 percent.
Production of seeds and oil was also reduced.
'What was surprising about this research was that plants exposed to ozone levels that peaked in the late afternoon suffered more damage than plants exposed to a steady ozone concentration throughout the day, even though average ozone concentrations were the same for both groups,' said Manning.
'This shows that current ozone standards that rely on average concentrations would underestimate crop losses,' he added.
Climate Progress post regarding the Republican plan to obstruct the EPA:
It’s worth remembering that the ad campaign that defeated prop 23 featured a little girl wearing an oxygen mask, lying on a hospital bed with her teddy bear, and the words “WHAT’S taking her breath away?” – not shrinking ice caps far away, or sea level rise in 2100.
What moves people is the safety of their children, and immediate issues, like food on the table. The EPA’s own website reports that ozone causes billions of dollars of crop damage in the form of reduced yields annually in the US – and that the background levels are inexorably rising.
I wish Lisa Jackson would make that connection between burning dirty fuel and the availability of food for the American public. I also wish EPA would muster its resources to investigate the effects of the emissions of ozone precursors emitted from burning ethanol, (a subject about which their silence is deafening) since acetaldehyde enhances the production of peroxyacetyl nitrates – making an even worse toxin for vegetation than ozone from gasoline and coal.
It's good news week!ReplyDelete
Then too, ozone may be killing off the honey bees and that's leading to additional crop losses by changing the scent of the flowers and pollen that feed the hive. But you probably already knew that.
Groan... we are so... you know what.ReplyDelete
As if we could just blithely do what we want to do - not because we need but just because we *want* it - and ignore all those delicate loops that nature wove.
But thanks for sharing!