Silent Spring - has the lesson been learned?

It's now 48 years since Rachel Carson's 'Silent Spring' was published and marked a foundation point in defining the inherent risk of uncritical acceptance of  pesticides impact on the enivronment. Released by Houghton Mifflin on 27 September 1962,  the book itself is widely credited with helping launch the environmental movement and documented the detrimental effects of pesticides on the environment, particularly on birds. Carson who was a scientist, said that DDT had been found to cause thinner egg shells and result in reproductive problems and death. The chemical industry was criticised for spreading disinformation with public officials accepting industry claims uncritically.

Even with greater awareness, controls and regulation, high level risk continues. The Californian Condor, an endangered species, appears to be the next potential victim of contamination producing eggs with dangerously thin shells. A possible culprit is exposure to DDT through the food chain as condors feed off sea lions who in turn eat contaminated fish from an offshore dumping ground.
[New Scientist 20 November 2010]

Shades of Grey and Life's Momentum

Life has become compressed in the 21st Century and more focussed on the absolutes of black and white rather than shades of grey which actually characterises the bulk of life's events. Thus observed prominent and sometimes controverial Australian photographer and artist, Bill Henson, at the Art Gallery of NSW last night. Presenting the final talk of the photographic series 'My Favourite Things', Bill Henson observed the speed at which events, moments and decisions are reached, often with insufficient consideration and often less understanding.   

Henson's photographic work reflects an interest in ambiguity and in particular, transition. His photographs often resemble the texture and composition of a painting rather than a photograph. With this perspective he is well placed not only to observe change but to arbitrage between new technology and  retaining a passion for earlier, more measured forms of creative expression in music, film and other art forms. Music is one such linear transition he commented moving from vinyl to tape to CD and now to MP3 digital capture, yet condensing does not always guarantee retention of content or value. An obervation well placed.

Native cuisine - alternative diet

Over the past two decades there have been various experiments with changing Western culinary habits by introducing additional species to the human cuisine most often being native species as an alternative to the domestic cattle, sheep and farmed birds. In Australia this has included kangaroos, emus and water buffalo. This has met with only mixed success but of these species, kangaroos have offered the most likely option for adoption into diets. A strong incentive for the uptake of kangaroo can be seen with the following data.

Tonnes per head per year (carbon equivalents)

• 0.003 - Kangaroo
• 0.14 - Sheep
• 1.67 - Cattle

Fat Content per 100kg of raw meat

• 6.3g - Beef (lean fillet)
• 5.8g - Lamb (trimmed steak)
• 1.5g - Chicken
• 1.3g - Kangaroo

[Source: New Scientist No 2781 9 October 2010]

Global warming - facing an unpopular truth

The second Festival of Dangerous Ideas was held at the Sydney Opera House over the October 2010 long weekend featuring an array of topics in 24 separate panel debates and individual presentations. From a climate change perspective, the message remained clear with a projected grim outlook for the planet from 2020 onwards. Of note, the session titled 'We are all Climate Change Deniers' presented by Clive Hamilton, Professor of Public Ethcis at the Centre for Applied Philosophy and Public Ethics demonstrated the stark reality that global warming is occuring and is on a trajectory for a major impact within this century. Even the 2 degree C target would still result in Artic summer ice, Himalayan Tibetan glaciers and the Greenland ice sheet melting. The evidence now shows a temperature rise of between 2 and 4 degrees C which will result in the loss of Amazon rainforest (one of the World's main oxygen generators) and the West Antartic ice sheet as well as many other effects. Yet despite the evidence, there remains vocal and powerful interests that seek to deny there is any risk as well as nullify any debate.

Life beyond in the stars?

The recent pronuncement that Gliese 581g, a planet orbiting the red dwarf star Gliese 581 may be suitable for life should not come as any surprise. Located approximately 20.5 light years away from Earth in the constellation of Libra, the planet is located in the middle of the "Goldilocks" zone, or what is defined as a habitable part of space near its parent star. The existence of liquid water is considered a strong possibility and this condition is generally considered a precursor for life. The planet was discovered by the Lick-Carnegie Exoplanet Survey following a period of over ten years of observations. Gliese 581g is believed to be the first Goldilocks planet ever found being the most earth-like planet with the potential for harboring life. The search for life in the universe continues both through optical astronomy and radio astronomy (the SETI program). The question remains, if life is found, what would the human race do?

Ozone layer recovering following CFC reduction

Some positive news for the environment comes with confirmation from the UN Environment Program (UNEP) that the ozone level in the Earth's upper atmosphere is recovering following the removal of harmful ozone depleting substances from use in human activities.

As UNEP advises "..The Montreal Protocol on Substances that Deplete the Ozone Layer was adopted in 1987 to protect global ozone and, consequently, protect life from increased ultraviolet (UV) radiation at Earth’s surface. Chlorine- and bromine-containing substances that are controlled by the Montreal Protocol are known as ozone-depleting substances (ODSs). ODSs are responsible for the depletion of stratospheric ozone observed in polar regions (for example, the “ozone hole” above Antarctica) and in middle latitudes. The severe depletion of stratospheric ozone observed in the Antarctic has increased UV at the surface and affected climate at southern high latitudes..'.

This is a long overdue bit of good news and demonstrates the World's capacity for taking the necessary steps when a clear course of action was needed.

Loss of carbon absorption another impact of drought

The latest issue of Science carries some concerning research showing a reduction in the level of trees/plants to provide carbon sinks for the planet. Drought and changed rainfall patterns have apparently led to this reduction of plant coverage but this in turn places an urgent emphasis on taking steps to replace plant loss as well as develop other alternative methods to capture carbon emissions.

Science 20 August 2010:

Vol. 329. no. 5994, pp. 940 - 943
DOI: 10.1126/science.1192666

Drought-Induced Reduction in Global Terrestrial Net Primary Production from 2000 Through 2009
Maosheng Zhao* and Steven W. Running

Terrestrial net primary production (NPP) quantifies the amount of atmospheric carbon fixed by plants and accumulated as biomass. Previous studies have shown that climate constraints were relaxing with increasing temperature and solar radiation, allowing an upward trend in NPP from 1982 through 1999. The past decade (2000 to 2009) has been the warmest since instrumental measurements began, which could imply continued increases in NPP; however, our estimates suggest a reduction in the global NPP of 0.55 petagrams of carbon. Large-scale droughts have reduced regional NPP, and a drying trend in the Southern Hemisphere has decreased NPP in that area, counteracting the increased NPP over the Northern Hemisphere. A continued decline in NPP would not only weaken the terrestrial carbon sink, but it would also intensify future competition between food demand and proposed biofuel production.

Numerical Terradynamic Simulation Group, Department of Ecosystem and Conservation Sciences, the University of Montana, Missoula, MT 59812, USA.