Health

New Zealand firm defends milk safety after chemical find

New Zealand's Fonterra, the world's largest dairy exporter, said Monday that its milk was "100 percent" safe to drink despite tests finding trace elements of an agricultural chemical in milk powder.

Other

Radiologists: Going green with small, simple step

Having radiologists shut down their workstations (and monitors) after an eight hour shift leads to substantial cost savings and energy reduction, according to a study in the November issue of the Journal of the American College ...

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Greenhouse gas

Greenhouse gases are gases in an atmosphere that absorb and emit radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. Common greenhouse gases in the Earth's atmosphere include water vapor, carbon dioxide, methane, nitrous oxide, and ozone. In our solar system, the atmospheres of Venus, Mars and Titan also contain gases that cause greenhouse effects. Greenhouse gases greatly affect the temperature of the Earth; without them, Earth's surface would be on average about 33°C (59°F) colder than at present.

Human activities since the start of the industrial era around 1750 have increased the levels of greenhouse gases in the atmosphere. The 2007 assessment report compiled by the IPCC observed that "changes in atmospheric concentrations of greenhouse gases and aerosols, land cover and solar radiation alter the energy balance of the climate system", and concluded that "increases in anthropogenic greenhouse gas concentrations is very likely to have caused most of the increases in global average temperatures since the mid-20th century".

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