And some schemes have attracted controversy: In July 2012, for example, 100 tonnes of iron sulphate was deposited into the Pacific Ocean, off Canada's west coast, in an attempt to help restore salmon stocks there.
Taking the US as an example, 884 tonnes of bismuth were consumed in 2010, of which 63% went into chemicals (including pharmaceuticals, pigments, and cosmetics), 26% into metallurgical additives for casting and galvanizing, 7% into bismuth alloys, solders and ammunition, and 4% into research and other uses.
Relative to other large North American cities, Toronto has lower GHG emissions (Graph A) per capita (at 7.33 tonnes per capita) than, for example, Boston (10.8 tonnes per capita) and Los Angeles (13.39 tonnes per capita).
Thailand, for example, donated 5,000 tonnes of rice from government stockpiles swollen by an expensive price-support scheme.
Hunt has said, for example, that 200m tonnes of abatement will come from the "safeguards mechanism" pushing heavy industry to reduce its emissions, but the mechanism is now set at levels that do not deliver any emission reductions.
The World Food Programme, for example, delivered 2.7m tonnes of emergency food aid to 43m people last year.On the other hand, chronic hunger a steady lack of enough safe and nutritious food to maintain physical or mental well-being is a less visible condition, even if a far more common and complex one.
There are, for example, millions of tonnes of mineral ore parked in Chinese ports going nowhere.
Dutch company Orthometals, for example, collects 250 tonnes of metal every year from hundreds of crematoriums around Europe.
In Sleipner, for example, a million tonnes of CO2 per year is captured from a gas field and stored in the Utsira sandstone.
U.N. figures show, for example, that 46,500 tonnes of building materials came into Gaza via the Kerem Shalom crossing from Israel in September 2011, while 90,000 tonnes came via the tunnels.
