carbon dioxide ice plant
41Coal — Sedimentary Rock Anthracite coal Composition Primary carbon Secondary hydrogen, sulfur …
42Effects of global warming — This article is about (primarily) effects during the 21st century. For longer term effects, see Long term effects of global warming. The variou …
43IPCC Fourth Assessment Report — IPCC Assessment reports: First (1990) 1992 sup. Second (1995) Third (2001) Fourth (2007) …
44Hypothetical types of biochemistry — are forms of biochemistry speculated to be scientifically viable but not proven to exist at this time. While the kinds of living beings we know on earth commonly use carbon for basic structural and metabolic functions, water as a solvent and DNA… …
45Alternative biochemistry — is the speculative biochemistry of alien life forms that differ radically from those on Earth. It includes biochemistries that use elements other than carbon to construct primary cellular structures and/or use solvents besides water. Theories… …
46Antarctica — /ant ahrk ti keuh, ahr ti /, n. the continent surrounding the South Pole: almost entirely covered by an ice sheet. ab. 5,000,000 sq. mi. (12,950,000 sq. km). Also called Antarctic Continent. * * * Antarctica Introduction Antarctica Background:… …
47agricultural technology — Introduction application of techniques to control the growth and harvesting of animal and vegetable products. Soil preparation Mechanical processing of soil so that it is in the proper physical condition for planting is usually… …
48Glossary of fuel cell terms — The Glossary of fuel cell terms lists the definitions of many terms used within the fuel cell industry. The terms in this glossary may be used by fuel cell industry associations, in education material and fuel cell codes and standards to name but …
49Anoxic event — As early as 1911, major oceanic currents were well mapped and understood, albeit without today s understanding of how they affect regional and global climatological conditions …
50Ordovician Period — Interval of geologic time, 490–443 million years ago, the second oldest period of the Paleozoic Era. It follows the Cambrian and precedes the Silurian. During the Ordovician, many of the landmasses were aligned in the tropics. Life was dominated… …
