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Dear Colleagues, 

As you remember, it was identified during the evaluation session of EcoSanRes training in Ukraine that the EcoSan professionals from the group need a ‘meeting space’ for communication and sharing. 
Earth Forever made provisions to provide this ‘meeting space’ at its website. 
Please, feel most welcome to use the forum to share and discuss any EcoSan topics connected to your field work and research. 

The forum languages are English, Russian and Bulgarian.  

Diana Iskreva,
Earth Forever, Executive Director


  Google Groups

UK Scientists Report: ‘Ocean changes will cool Europe’

Nature Magazine reports that the North Atlantic's natural heating system, which brings clement weather to western Europe, is showing signs of decline. UK scientists report in a letter in the Dec. 1, 2005 issue that warm Atlantic Ocean currents, which carry heat from the tropics to high latitudes, have substantially weakened over the past 50 years. Oceanographers surveying the current system that includes the warm Gulf Stream current, report that it seems to be 30% weaker than half a century ago. Failures of the Atlantic Ocean's circulation system are thought to have been responsible for abrupt and extreme climate changes during the ice age that lasted from 110,000 to 23,000 years ago. Both salinity and water density, which influence the transport of warm waters, have previously been found to be decreasing. The likely cause is more fresh water flowing into the ocean from rivers, rain and melting ice, and this is thought to be linked to global warming. But climate modellers are worried that the resulting weakening of ocean currents could ultimately lead to substantial cooling of the North Atlantic.


Impact of Global Warming on Carbon Cycle

A team of European scientists led by Philippe Ciais evaluated how net carbon exchange of ecosystems respond to global warming using a "natural experiment": the episode of heat and drought that affected Europe in 2003 (Nature, 437: 529-533, 2005). Future climate warming is expected to enhance plant growth in temperate ecosystems and to increase carbon sequestration however its impact on terrestrial carbon cycling is unclear. Ciais et al. reported measurements of ecosystem carbon dioxide fluxes, remotely sensed radiation absorbed by plants, and country-level crop yields taken during the European heat wave in 2003. A 30 per cent reduction in gross primary productivity, unprecedented during the last century, was estimated over Europe, resulting in a strong anomalous net source of carbon dioxide (0.5 Pg C yr-1) to the atmosphere and reversing the effect of four years of net ecosystem carbon sequestration. Ecosystem respiration decreased together with gross primary productivity, rather than accelerating with the temperature rise. The reduction of both photosynthesis and respiration will increase atmospheric carbon dioxide and amplify the carbon-cycle feedback on climate warming. A repeat of extreme temperatures could turn temperate ecosystems into carbon sources, and affect the ability of European countries to comply with the requirements of the Kyoto protocol.


Reported in Science Magazine: Ice core extended to
740,000 years

Air trapped in glacial ice contains the only reliable direct record of atmospheric composition before scientific sampling began in the 18th century. Two reports in the November 25, 2005 edition of Science Magazine present data on the composition of the atmosphere between 400,000 and 650,000 years ago, an interval soon after glacial cycles switched to the period that occurs today. Siegenthaler et al. present measurements of the atmospheric concentration of CO2, the most important trace greenhouse gas, and show how its concentration varied during a much more narrow range than it did during the past 400,000 years. Spahni et al. present parallel measurements for two other important trace greenhouse gases, CH4 and N2O.

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