Monthly Archives: May 2013

World Population

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The world population is the total number of living humans on Earth. As of today, it is estimated to number 7.086 billion by the United States Census Bureau (USCB).[1] The USCB estimates that the world population exceeded 7 billion on March 12, 2012.[2] According to a separate estimate by the United Nations Population Fund, it reached this milestone on October 31, 2011.[3][4][5]

The world population has experienced continuous growth since the end of the Great Famine and the Black Death in 1350, when it stood at around 370 million.[6] The highest rates of growth – global population increases above 1.8% per year – were seen briefly during the 1950s, and for a longer period during the 1960s and 1970s. The growth rate peaked at 2.2% in 1963, and had declined to 1.1% by 2011. Total annual births were highest in the late 1980s at about 138 million,[7] and are now expected to remain essentially constant at their 2011 level of 134 million, while deaths number 56 million per year, and are expected to increase to 80 million per year by 2040.[8]

Current projections show a continued increase in population in the near future (but a steady decline in the population growth rate), with the global population expected to reach between 7.5 and 10.5 billion by 2050.[2][9][10] Various longer-term estimates predict further growth, stagnation, or even overall decline in the global population by 2150.[11] Some analysts have questioned the sustainability of further world population growth, citing the growing pressures on the environment, global food supplies, and energy resources.[12][13][14]

World population (millions)[15]
# Top ten most populous countries 1990 2008 2025*
1 China 1,141 1,333 1,458
2 India 849 1,140 1,398
3 United States 250 304 352
4 Indonesia 178 228 273
5 Brazil 150 192 223
6 Pakistan 108 166 226
7 Bangladesh 116 160 198
8 Nigeria 94 151 208
9 Russia 148 142 137
10 Japan 124 128 126
World total 5,265 6,688 8,004
Top ten most populous (%) 60.0% 58.9% 57.5%
1 Asia 1,613 2,183 2,693
+ China 1,141 1,333 1,458
+ OECD Pacific* 187 202 210
2 Africa 634 984 1,365
3 Europe* 564 603 659
+ Russia 148 142 137
+ ex-Soviet Union* 133 136 146
4 Latin America 355 462 550
5 North America* 359 444 514
6 Middle East 132 199 272
Australia 17 22 28
European Union – 27 states 473 499 539
US + Canada 278 338 392
Ex-Soviet Union 289 285 289
Geographical definitions as in IEA Key Stats 2010 p. 66
Notes:

  • Europe = OECD Europe + Non-OECD Europe and
    excluding Russia and including Estonia, Latvia and Lithuania
  • ex-Soviet Union (SU) = SU excluding Russia and Baltic states
  • North America = US, Canada, Mexico
  • OECD Pacific = Australia, Japan, Korea, New Zealand
  • 2025 = with constant annual 2007/2008 growth until 2025

Source: World population – Wikipedia, the free encyclopedia

Oceans

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Earth is the only planet known to have an ocean (or any large amounts of open liquid water). Approximately 72% of the planet’s surface (~3.6×108 km2) is covered by saline water that is customarily divided into several principal oceans and smaller seas, with the ocean covering approximately 71% of the Earth’s surface.[6] In terms of the hydrosphere of the Earth, the ocean contains 97% of the Earth’s water. Oceanographers have stated that out of 97%, only 5% of the ocean as a whole on Earth has been explored.[6] Because it is the principal component of Earth’s hydrosphere, the world ocean is integral to all known life, forms part of thecarbon cycle, and influences climate and weather patterns. The total volume is approximately 1.3 billion cubic kilometres (310 million cu mi)[7] with an average depth of 3,682 metres (12,080 ft).[8] It is the habitat of 230,000 known species, although much of the ocean’s depths remain unexplored and it is estimated that over two million marine species exist.[9] The origin of Earth’s oceans is still unknown, but oceans are believed to have formed in the Hadean period and may have been the impetus for the emergence of life.

Rank Ocean Notes
1 Pacific Ocean Separates Asia and Oceania from the Americas[14]
2 Atlantic Ocean Separates the Americas from Eurasia and Africa
3 Indian Ocean Washes upon southern Asia and separates Africa and Australia[14][15][16]
4 Southern Ocean Sometimes considered an extension of the Pacific, Atlantic and Indian Oceans,[11][17] which encircles Antarctica
5 Arctic Ocean Sometimes considered a sea of the Atlantic, which covers much of the Arctic and washes upon northern North America and Eurasia

Earth

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Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System’s four terrestrial planets. It is sometimes referred to as the world or the Blue Planet.[22]

Earth formed approximately 4.54 billion years ago, and life appeared on its surface within its first billion years.[23]Earth’s biosphere then significantly altered the atmospheric and other basic physical conditions, which enabled the proliferation of organisms as well as the formation of the ozone layer, which together with Earth’s magnetic field blocked harmful solar radiation, and permitted formerly ocean-confined life to move safely to land.[24] Thephysical properties of the Earth, as well as its geological history and orbit, have allowed life to persist. Estimates on how much longer the planet will be able to continue to support life range from 500 million years (myr), to as long as 2.3 billion years (byr).[25][26][27]

Earth’s lithosphere is divided into several rigid segments, or tectonic plates, that migrate across the surface over periods of many millions of years. About 71% of the surface is covered by salt water oceans, with the remainder consisting of continents and islands which together have many lakes and other sources of water that contribute to the hydrosphere. Earth’s poles are mostly covered with ice that is the solid ice of the Antarctic ice sheet and the sea ice that is the polar ice packs. The planet’s interior remains active, with a solid iron inner core, a liquidouter core that generates the magnetic field, and a thick layer of relatively solid mantle.

Earth gravitationally interacts with other objects in space, especially the Sun and the Moon. During one orbit around the Sun, the Earth rotates about its own axis 366.26 times, creating 365.26 solar days, or one sidereal year.[note 7] The Earth’s axis of rotation is tilted 23.4° away from the perpendicular of its orbital plane, producing seasonal variations on the planet’s surface with a period of one tropical year (365.24 solar days).[28] The Moon is Earth’s only natural satellite. It began orbiting the Earth about 4.53 billion years ago (bya). The Moon’s gravitational interaction with Earth stimulates ocean tides, stabilizes the axial tilt, and gradually slows the planet’s rotation.

The planet is home to millions of species of life, including humans.[29] Both the mineral resources of the planet and the products of the biosphere contribute resources that are used to support a global human population.[30]These inhabitants are grouped into about 200 independent sovereign states, which interact through diplomacy, travel, trade, and military action. Human cultures have developed many views of the planet, including itspersonification as a planetary deity, its shape as flat, its position as the center of the universe, and in the modern Gaia Principle, as a single, self-regulating organism in its own right.

Source: Earth – Wikipedia, the free encyclopedia

 

Natural Resources

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Natural resources occur naturally within environments that exist relatively undisturbed by mankind, in a natural form. A natural resource is often characterized by amounts of biodiversity and geodiversity existent in various ecosystems.

Natural resources are derived from the environment. Some of them are essential for our survival while most are used for satisfying our wants. Natural resources may be further classified in different ways.

Natural resources are materials and components (something that can be used) that can be found within the environment. Every man-made product is composed of natural resources (at its fundamental level). A natural resource may exist as a separate entity such as fresh water, and air, as well as a living organism such as a fish, or it may exist in an alternate form which must be processed to obtain the resource such as metal ores, oil, and most forms of energy.

There is much debate worldwide over natural resource allocations, this is partly due to increasing scarcity (depletion of resources) but also because the exportation of natural resources is the basis for many economies (particularly for developed nations such as Australia).

Some natural resources such as sunlight and air can be found everywhere, and are known as ubiquitous resources. However, most resources only occur in small sporadic areas, and are referred to as localized resources. There are very few resources that are considered inexhaustible (will not run out in foreseeable future) – these are solar radiation, geothermal energy, and air (though access to clean air may not be). The vast majority of resources are exhaustible, which means they have a finite quantity, and can be depleted if managed improperly.

Source: Natural resource – Wikipedia, the free encyclopedia

The Geysers (Geothermal Power Plants)

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The Geysers is a complex of 22 geothermal power plants, drawing steam from more than 350 wells, located in the Mayacamas Mountains 72 mi (116 km) north of San Francisco,California. The largest in the world, the Geysers has 1517 MW[1] of active installed capacity with an average production factor of 63% (955 MW).[2] Calpine Corporationoperates and owns 19 of the 22 active plants in the Geysers and is currently the United States’ largest producer of geothermal energy. Two other plants are owned jointly by theNorthern California Power Agency and the City of Santa Clara‘s municipal Electric Utility (now called Silicon Valley Power). The Bottle Rock Power plant was owned by the US Renewables Group and reopened in October 2007.[3] Another plant is under development by Ram Power Corp,[4] formerly Western Geopower, with operation set to begin in 2010. Since the activities of one geothermal plant affects those nearby, the consolidation of plant ownership at The Geysers has been beneficial because the plants operate cooperatively instead of in their own short-term interest.

Source: The Geysers – Wikipedia, the free encyclopedia

Windmill

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A wind turbine or windmill is a device that converts kinetic energy from the wind, also called wind energy, into mechanical energy; a process known as wind power. If the mechanical energy is used to produce electricity, the device may be called a wind turbine or wind power plant. If the mechanical energy is used to drive machinery, such as for grinding grain or pumping water, the device is called a windmill or wind pump. Similarly, it may be referred to as a wind charger when used for charging batteries.

The result of over a millennium of windmill development and modern engineering, today’s wind turbines are manufactured in a wide range of vertical and horizontal axis types. The smallest turbines are used for applications such as battery charging or auxiliary power on boats; while large grid-connected arrays of turbines are becoming an increasingly important source of wind power-produced commercial electricity.

Source: Wind turbine – Wikipedia, the free encyclopedia

Ocean Wave Power Generator

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An ocean wave power generator converts tidal energy into mechanical and electrical energy.

Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into useful forms of power – mainly electricity.

Although not yet widely used, tidal power has potential for future electricity generation. Tides are more predictable than wind energy and solar power. Among sources of renewable energy, tidal power has traditionally suffered from relatively high cost and limited availability of sites with sufficiently high tidal ranges or flow velocities, thus constricting its total availability. However, many recent technological developments and improvements, both in design (e.g. dynamic tidal power, tidal lagoons) and turbine technology (e.g. new axial turbines, cross flow turbines), indicate that the total availability of tidal power may be much higher than previously assumed, and that economic and environmental costs may be brought down to competitive levels.

Historically, tide mills have been used, both in Europe and on the Atlantic coast of North America. The incoming water was contained in large storage ponds, and as the tide went out, it turned waterwheels that used the mechanical power it produced to mill grain.[1] The earliest occurrences date from the Middle Ages, or even from Roman times.[2][3] It was only in the 19th century that the process of using falling water and spinning turbines to create electricity was introduced in the U.S. and Europe.[4]

The world’s first large-scale tidal power plant (the Rance Tidal Power Station) became operational in 1966.

Tidal Wave Power Generator

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The Aguçadoura Wave Farm was the world’s first wave farm. It used tidal wave power generators to generate electricity. It was located 5 km (3 mi) offshore near Póvoa de Varzim north of Porto in Portugal. The farm was designed to use three Pelamis wave energy converters to convert the motion of the ocean surface waves into electricity, totalling to 2.25 MW in total installed capacity. The farm was officially opened on 23 September 2008, by the Portuguese Minister of Economy.[1][2] The wave farm was shut down two months after the official opening in November 2008.[3][4]

Source: Aguçadoura Wave Farm – Wikipedia, the free encyclopedia

 

Solar Mirror Farm

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The PS10 Solar Power Plant (Spanish: Planta Solar 10), is a solar mirror farm. It is the world’s first commercial concentrating solar power tower operating near Seville, in Andalusia, Spain. The 11 megawatt (MW) solar power tower produces electricity with 624 large movable mirrors called heliostats.[2] It took four years to build and so far cost €35 million (US$46 million).[3] PS10 produces about 23,400 megawatt-hours (MW·h) per year, for which it receives €271 (US$360) per MW·h under its power purchase agreement; equating to a revenue of €6.3 million per year.[4]

Solar Thermal Collector

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A solar thermal collector is a solar collector designed to collect heat by absorbing sunlight. A collector is a device for converting the energy in sunlight, or solar radiation, into a more usable or storable form. This energy is in the form ofelectromagnetic radiation from the infrared (long) to the ultraviolet (short) wavelengths. The quantity of solar energy striking the Earth’s surface averages about 1,000 watts per square meter under clear skies, depending upon weather conditions, location, and orientation of the surface.

The term solar collector refers to solar hot water panels, but may also refer to more complex installations such as solar parabolic apparatus, solar troughs, and solar towers; or less complex installations such as solar air heat. Solar power plants usually use the more complex collectors to generate electricity by heating water to produce steam which drives aturbine connected to an electrical generator. The less complex collectors are typically used in residential and commercial buildings for supplemental space heating. perpendicular to the sun’s rays.