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Subject: Music

This US group was formed in Los Angeles, California, in 1978 by Steve Allen (guitar, vocals) and Ron Flynt (bass, vocals), two expatriate musicians from Tulsa, Oklahoma. Drummer Mike Gallo ...

Ground Water

Ground Water   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

...ancient, deteriorating pipe and sewer systems. This is happening in British cities such as London, Liverpool, and Birmingham. In London, a 46% reduction in ground-water withdrawal has caused the water table in the Cretaceous chalk and younger Tertiary beds to rise by as much as 20 meters. Such a rise has numerous effects: • increased spring and river flows • reemergence of flow from dry springs • surface flooding • pollution of surface and underground waters • flooding of basements • increased leakage into tunnels • reduction in stability of slopes...

Wind Chill

Wind Chill   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
1,156 words
Illustration(s):
1

...Wind Speed (miles per hour) °F Calm 5 10 15 20 25 30 35 40 32 66 32 22 16 11 7 5 3 2 30 64 30 20 13 8 5 3 1 −1 28 63 28 18 11 6 3 0 −2 −4 26 63 26 16 9 3 0 −3 −5 −7 24 61 24 13 6 0 −3 −6 −8 −10 22 61 22 11 3 −2 −6 −9 −11 −13 20 60 20 8 0 −5 −9 −12 −14 −16 18 59 18 6 −2 −8 −12 −15 −17 −19 16 58 16 4 −5 −10 −15 −18 −20 −22 14 57 14 1 −8 −13 −18 −21 −23 −25 12 56 12 −1 −10 −16 −21 −24 −26 −28 10 56 10 −4 −12 −19 −24 −27 −29 −31 8 54 8 −6 −15 −21 −26 −30 −32 −34 6 53 6 −8 −18 −24 −29 −33 −35 −37 4 52 4 −11 −20 −27 −32 −35 −38 −40 2 51 2 −13 −23 −30 −35 −38...

North Atlantic Oscillation

North Atlantic Oscillation   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

... 1941–1944 , 1962–1963 , and 1968–1969 ). It has been argued that the negative mode of the NAO is a good analogue to the atmospheric circulation that prevailed during both the European Little Ice Age, from about 1450 to 1850 , and the last ice age glacial maximum at around 18 to 20 thousand years ago. The winter index of the NAO varies on an approximately biennial basis when one considers a run of years, but it also shows some variability from decade to decade. The 1960s displayed an extreme negative phase whereas a prolonged positive phase occurred in the...

Climatic Zones

Climatic Zones   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
1,955 words
Illustration(s):
2

...20 over 68 over 10 over 50 Temperature under 20 under 68 over 10 over 50 Cold under 20 under 68 under 10 under 50 b. Köppen's 1884 thermal zones: Duration in Months of Critical Temperatures Above 20°C (68°F) 10 to 20°C (50 to 68°F) Below 10°C ( below 50°F) Tropical 12 — — Subtropical 4 to 11 1 to 8 — Temperate less than 4 4 to 12 less than 4 Cold — 1 to 4 8 to 11 Polar — — 12 c. Herbertson's 1905 thermal zones and economic belts: Economic Belt Temperature Limits, °C No crops <10 Very few crops 0–10 Temperate climate crops 10–20 Tropical crops >20 d....

North America

North America   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
3,860 words
Illustration(s):
3

...of as unrelentingly frigid. The amount of bitterly cold weather (minimum temperatures below −20°C), however, varies considerably throughout the country. On average, the number of bitterly cold days varies from near zero along the Pacific Coast, around Lake Erie, and on the outer Atlantic Coast, to 210 days at Eureka in the Northwest Territories. In a typical year there are 5 very cold days in the interior of British Columbia, 60 across the eastern prairies, 20 in central Ontario, 30 over the Gaspe Peninsula, and more than 100 in the Yukon. Temperature....

Salinization

Salinization   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
2,511 words
Illustration(s):
1

...44.83 46.2 6.70 15.0 India 168.99 42.10 24.9 7.00 16.6 Commonwealth of Independent States 232.57 20.48 8.8 3.70 18.1 United States 189.91 18.10 9.5 4.16 23.0 Pakistan 20.76 16.08 77.5 4.22 26.2 Iran 14.83 5.74 38.7 1.72 30.0 Thailand 20.05 4.00 19.9 0.40 10.0 Egypt 2.69 2.69 100.0 0.88 33.0 Australia 47.11 1.83 3.9 0.16 8.7 Argentina 35.75 1.72 4.8 0.58 33.7 South Africa 13.17 1.13 8.6 0.10 8.9 Subtotal 842.80 158.70 18.8 29.62 20.0 World 1473.70 227.11 15.4 45.4 20.0 Source: Ghassemi et al., 1995, Table 18. With permission of the Centre for Resource and...

Albedo

Albedo   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

...planetary albedo at the top of the atmosphere (TOA) is approximately 0.3. Since clouds are highly reflective, with albedos ranging up to about 0.8, and cover approximately 60% of the Earth, they have a dominant effect on planetary albedo. On average, clouds reflect approximately 20% of the solar radiation reaching the planet, compared with 6% reflected by gas molecules and aerosols and 4% by the Earth's surface. The Global Picture Regions where clouds have a large influence on planetary albedo are areas of persistent low stratiform clouds over the eastern...

Biofuels

Biofuels   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

...Palm Oil May Be an Eco-Nightmare.” New York Times , January 31, 2007. RSB, 2007. Draft Global Principles for Sustainable Biofuels Production . Roundtable on Sustainable Biofuels, Lausanne, Switzerland, 2007 ( http://cgse.epfl.ch/webdav/site/cgse/shared/Biofuels/RSB%20Draft%20Principles%20-%20June%205,%202007.pdf ; accessed May 27, 2008). Sheehan, J. , et al. “An Overview of Biodiesel and Petroleum Diesel Life Cycles.” U.S. Department of Energy, TP-580-24772. National Renewable Energy Lab, 1998. Turner, R. Eugene , and N. Rabalais . “2007 Forecast of the...

United Nations Environment Programme

United Nations Environment Programme   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005

...thirteen from Asia, ten from Latin America and the Caribbean, and six from eastern Europe. The organization's secretariat is located in Nairobi, Kenya, making it the first UN agency to be headquartered in a developing country. The budget of the organization has grown from U.S.$20 million in 1973 to approximately U.S.$105 million in 1997 . The four Executive Directors of UNEP ( Maurice Strong of Canada, 1973–1975 ; Mostafa Tolba of Egypt, 1976–1992 ; Elizabeth Dowdswell of Canada, 1993–1998 ; and Klaus Töpfer , 1998 to the present) have played...

Latent Heat

Latent Heat   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011

...to evaporate. The latent heat of vaporization thus decreases as temperature increases. For example, the latent heat of vaporization equals 2,454 joules per gram at 20°C, and 2,261 joules per gram at 100°C. Similarly, these molecules contain less internal energy at colder temperatures, so less energy is released when they freeze; the latent heat of fusion decreases to 289 joules per gram at −20°C. The transfer of energy through latent heat plays a significant role in the global energy balance. For example, more than 3 times as much energy is transferred from...

Paleomagnetic Evidence of Crustal Movement

Paleomagnetic Evidence of Crustal Movement   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

...polarity, were older, while innermost matching pairs were formed most recently. Sea-floor spreading and the continual birth of new ocean floor at the ridge were demonstrated (Figure 2). Bibliography Monastersky, R. “Earth's Heart Beats with a Magnetic Rhythm.” Science News (Nov. 20, 1993, 327. David J....

Global Electric Circuit

Global Electric Circuit   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
1,337 words
Illustration(s):
1

...charge attachment, and so on. Charge-separation processes usually fill the upper portion of the thundercloud with positive charge and the lower portion of the cloud with negative charge. The negative charge, typically around −20 coulombs, has been found to exist at heights where the temperature of the atmosphere is between −10°C and −20°C. This temperature range occurs between 6 and 8 kilometers for summer thunderstorms and around 2 kilometers for winter storms. The positive charge does not have such a clear relation with temperature and usually lies between 8...

Salinization

Salinization   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
3,373 words
Illustration(s):
2

...96.97 44.83 46.2 6.70 15.0 India 168.99 42.10 24.9 7.00 16.6 Commonwealth of 232.57 20.48 8.8 3.70 18.1 Independent States United States 189.91 18.10 9.5 4.16 23.0 Pakistan 20.76 16.08 77.5 4.22 26.2 Iran 14.83 5.74 38.7 1.72 30.0 Thailand 20.05 4.00 19.9 0.40 10.0 Egypt 2.69 2.69 100.0 0.88 33.0 Australia 47.11 1.83 3.9 0.16 8.7 Argentina 35.75 1.72 4.8 0.58 33.7 South Africa 13.17 1.13 8.6 0.10 8.9 Subtotal 842.80 158.70 18.8 29.62 20.0 World 1473.70 227.11 15.4 45.4 20.0 source : From Ghassemi et al. ( 1995 , Table 18). With permission of the Centre for...

Ozone

Ozone   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

...feature of the stratosphere, and a direct link has been established between anthropogenic chlorine and the large decrease in the ozone concentration, up to 90%, observed between 15 and 20 kilometers. Similar decreases have appeared since 1995 in the Arctic winter stratosphere, where record low temperatures (relative to the average values recorded over the last 20 years) have been observed. These measurements constitute additional evidence of the destructive effects of CFCs and halons on the stratospheric ozone layer. They are also a clear indication of...

Arctic

Arctic   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
2,983 words
Illustration(s):
1

...all-wavelength radiation, energy balance components (watts per square meter) over representative Arctic terrains Winter Summer Energy fluxes 1 R H L E G M R H L E G M Coastal tundra (Barrow, Alaska) 104 −41 −34 −9 −20 −17 14 1 2 0 Arctic sea ice 2 (>3 inches thick) 74 −6 −7 −61 −61 −22 10 0 12 0 Greenland ice sheet (70° north latitude) 91 29 −20 −11 −89 Source: Adapted mainly from Weller and Wendler ( 1990 ). 1 R = H + L E + G + M , where R is the surface balance of absorbed solar radiation and emitted terrestrial thermal radiation minus atmospheric...

Microclimate

Microclimate   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011

...biomes Microclimate. Table 2. Albedos and emissivities * Material Albedo Emissivity Fresh snow 0.70–0.95 0.99 Old snow 0.55 0.82 Dry sand 0.25–0.45 0.91–0.95 Wet sand 0.10 0.94–0.98 Dry peat 0.05–0.15 0.97 Asphalt 0.05–0.20 0.95 Concrete 0.10–0.35 0.71–0.90 Grass 0.20 0.90–0.95 Water var 0.03 ≤ but ≤ 1.0 0.99 Deciduous forests 0.20 (leaves) 0.95–0.98 Coniferous forests 0.10–0.15 0.97–0.98 * Albedo is the ratio of reflected shortwave radiation to incoming shortwave radiation. Emissivity is the ratio of total energy emitted from a surface for a...

Quasi-biennial Oscillation

Quasi-biennial Oscillation   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
2,319 words
Illustration(s):
2

...per second) than west winds (around 20 meters per second). • Maximum amplitudes of both phases typically occur near 20 hectopascal (about 28 kilometers high). • The average period is about 28 months. • Both period and amplitude vary considerably from cycle to cycle. As the last point indicates, the QBO is not a periodic oscillation, but is instead characterized by period lengths from less than 2 years to nearly 3 years. The variability of the QBO period is related to the seasonal cycle: at 50 hectopascal (about 20 kilometers high), the onset of the east...

South America

South America   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
2,757 words
Illustration(s):
1

...because of the Andes that divide it, differences in temperature are more pronounced from east to west than from north to south. In the east, the annual temperature range is 20°C, the largest in South America. With certain regional modifications, South America's climates generally conform to latitudinal zones: north of 20° south latitude, the climate is equatorial; from 20° to 30° south it is tropical; from 30° to 40° subtropical; from 40° to 50° warm temperate; and south of 50° cold temperate. Nevertheless, 10 climatic types are distinguishable ( Table...

Mount Pinatubo

Mount Pinatubo   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
3,086 words
Illustration(s):
2

...winds in the equatorial stratosphere at about 20 kilometer altitude that has an average period of twenty-seven months (Figure 1). Transport of the volcanic cloud was tracked on weather satellite images until June 17, after which sufficient ash fell out to make the plume hard to define, leaving mainly the gaseous component dominated by water and sulfur dioxide. After this, the spreading could be defined by the sulfur dioxide cloud, which was tracked and measured by the Total Ozone Mapping Spectrometer satellite at 20 (±6) megatons of sulfur dioxide. Mount...

Glacier Retreat Since the Little Ice Age

Glacier Retreat Since the Little Ice Age   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
773 words
Illustration(s):
1

...there is, as with most geomorphologic phenomena, a wide range of values, the variability of which is probably related to such factors as topography (especially slope), size, altitude, accumulation rate, and ablation rate. The rates of retreat can be very high, on the order of 20–70 meters per year over extended periods of some decades in the case of the more active examples, and alpine glaciers in many areas have retreated by several kilometers in the last 100 years or so. Glacier Retreat Since the Little Ice Age. Pedersen Glacier, Alaska, 1920.(National...

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