Java

WITH A population exceeding 120 million, crowded into a space about the size of NEW YORK state (but with nearly six times the population), the island of Java is one of the most densely populated places on Earth (2,070 inhabitants per square mi or 864 per square km). Java is not the largest of the islands of INDONESIA, but it is certainly the nation’s political, historical, and economic core, with 60 percent of Indonesia’s total population, and most of its wealth concentrated into less than 7 percent of the nation’s total land area. But the future may change this status, as mineral and fossil fuel wealth in the outer islands leads to increased migration away from Java and increased demands for political and economic autonomy.

The 13th-largest island in the world, Java is the fifth-largest island in the Malay Archipelago. It is the smallest of the Greater Sundas (which also include BORNEO, SUMATRA, and Sulawesi), with a total area of 48,830 square mi (125,205 square km). The island is bordered on the south by the INDIAN OCEAN, which drops relatively quickly to great depths, plummeting up to 24,440 ft (7,450 m) in the Java Trench, the deepest point in the Indian Ocean. The rest of the island is surrounded by shallower seas, on the west, the Sunda Strait, with the island of Sumatra only 16 mi (26 km) distant; on the north, the Java Sea; and on the east, the Bali Strait, separating Java from Bali by only 1 mi (1.6 km) at its narrowest.

Part of the Pacific RING OF FIRE, Java was formed from a series of volcanoes running west to east. There are more than 100 volcanoes, 13 active in recent history. Most of the high peaks are concentrated along the southern edge of the island, about 20 of which exceed 8,000 ft (2,424 m). Semeru, in the eastern part of the island, is the highest active volcano on Java (12,131 ft or 3,676 m) and erupted most recently in April 2004.

Merapi erupted in 1994, killing 37 and forcing 6,000 to evacuate the area. The most notable, however, is located just offshore to the west: Krakatau, site of the largest volcanic explosion of modern times (in 1883,killing 36,000 people in western Java and reddening the sky as far as Europe and America).

From the mountainous south, the island’s topography then slopes generally downward toward the north shore, where there are more level and fertile plains, followed by mangrove swamps and ample harbors. Most agriculture and population centers are thus concentrated on the north shore. The mountains also contain significant natural resources, including tin, sulfur, asphalt, manganese, limestone and marble. Petroleum deposits are located near Rembang and Surabaya in the north and northeast, and on the island of Madura. Rice is cultivated across Java, along with sugarcane, though much of the island is covered with dense forests, rich in plant and animal wildlife like the Javanese tiger, and teak and mahogany trees. Ornithology is especially diverse, including numerous species of peacock, quail, heron, cuckoo, and hornbill. Temperatures can vary from the mountaintops to the lowlands by up to 20 degrees.

One in three Javanese lives in cities, four of which have over 1 million inhabitants. The largest of these is JAKARTA, the capital of Indonesia, with its port of Tanjung Priok, 6 mi (9 km) to the east. Jakarta has recently become the center of one of the world’s densest and fastest growing conurbations, referred to as JABOTABEK (Jakarta, Bogor, Tangerang, and Bekasi), home to nearly 20 million people. Java’s other largest cities include Surabaya, the second-largest and center of much of Java’s industry and trade; Bandung, on a high plateau in the northwest, formerly the heart of Dutch coffee and tea plantations, and more recently home to high-tech industries such as aeronautics; and Semarang, the island’s fastest-growing city, on the northern coast. Jogyakarta, in central Java, is a smaller city but has been the spiritual and cultural heart of Javanese culture for centuries, and its ancient palaces and temples continue to make this Java’s main center for tourism.

Today, Java is almost entirely Muslim, but before Islam arrived in the area, the island was ruled by Hindu and Buddhist princes (Bali remains predominantly Hindu today). The name Java itself probably derives from a Sanskrit (ancient Hindu) word for the type of grain grown locally. Numerous temples survive from this period, notably Prambanan (from the 10th century), and Borobudur, the largest Buddhist temple in the world. These princes were at their height in the 1300s, when the Majapahit Empire dominated the entire archipelago, and Malayan became the lingua franca for most of southeast Asia. This empire was dismantled by waves of Arabic traders, until it disappeared altogether in 1518. Bantam and Mataram were the strongest sultanates in the region when the Europeans arrived in the late 16th century. The Dutch established themselves in 1619 at an old Javanese fort called Jakarta and renamed it Batavia.

Total control of Java was achieved in 1756 after the bloody Java War, followed by gradual assertion of Dutch control over the neighboring islands of Sumatra, Borneo, and the rest of what is now Indonesia by the end of the 19th century. External trade was controlled by Europeans, while internal trade was taken over by Chinese immigrants encouraged by the colonial administration. The Javanese economy was transformed into plantations for sugarcane—the largest producer in the world by the end of the nineteenth century. Conditions for the Javanese were rough under Dutch rule, and the Japanese occupation during World War II encouraged them to fight for independence, which was proclaimed in Jakarta in 1945 but not recognized by the Netherlands until 1949.

ETHNIC GROUPS

Three major ethnic groups occupy the island, each with their own language: Sundanese in the west (including Jakarta), Javanese over most of central and eastern Java (with about 75 percent of the population), and Toba Batak in the northeast corner and on Madura. Javanese culture is famous for its shadow puppets and gamelan orchestras. These three groups are by far the largest ethnic groups in all of Indonesia (Javanese 45 percent, Sundanese 14 percent, and Madurese 7.5 percent), and their language formed the basis for the national language, Bahasa Indonesia.

Current issues facing the Javanese include controlling the population expansion; programs for reducing family sizes were begun in the 1960s, accompanied by government resettlement projects, which also has a secondary aim of attempting to “Javanize” the Outer Islands of Indonesia, particularly in sensitive areas like Aceh in Sumatra, West Papua, and Kalimantan, all with strong separatist movements. Farmers are especially encouraged to emigrate to the other islands, but face resistance from locals who resent dominance from Java, politically or culturally. While Java is by no means dependent on the Outer Islands for its existence, the central government in Jakarta is certainly concerned with the loss of potential riches as the mineral wealth of these regions becomes more commercially developed and exploited.

Jamaica

JAMAICA, SOME 62 mi (100 km) south of CUBA, is the third-largest island in the CARIBBEAN SEA and is full of numerous terrain features and vegetation. Surrounding the island is a coastal plain with numerous bays and broad flatlands, especially along the southern coast. Along the north coast, lush vegetation and white sandy beaches attract many visitors. The interior of the country is full of vales and deep ridges. Bush-covered hummocks, sinkholes, and underground caves carve out the limestone-rich region. The Blue Mountains in the east provide a dramatic sight.

Numerous animals and plants are scattered throughout the lush land that supports a tropical moderate climate. The Jamaican hutia is the only native land mammal still alive and 20 species of bats inhabit the country. Crocodiles are found in the swamps, and lizards and frogs are present all across the island. Egrets are commonly seen flying through the air, and John Crows (turkey buzzards) are found in all areas. Woodpeckers, owls, and doves are also some other birds in the island. Throughout the surrounding waters, brain corals, soft-flowering corals, and over 700 species of fish are supported by the reefs in this part of the Caribbean Sea.

Christopher Columbus discovered Jamaica on May 4, 1494, and the Spanish controlled the island until the signing of the 1670 Treaty of Madrid, which handed direct power to the British. The British created a representative system of government, which gave the white settlers power to implement laws. This legislative system lasted until 1866.

Slavery in Jamaica lasted until 1834. By that year, the country consisted of more than 311,000 slaves and only around 16,700 whites. For almost 200 years, slaves were found throughout Jamaican sugar plantations. Estimates state that over 1 million slaves were transported from Africa to Jamaica during this period. Runaway slave communities were created on the island and they even fought successful small-scale battles against British soldiers.

With the decline of plantation life and rise of black revolts, the British government took direct control of the government. They implemented rules where landowners were required to produce titles of ownership. Many of the black peasants did not have the titles and were thus forced off their land. The plantation economy of Jamaica formed once again with the sugar and banana industries, and thousands of the blacks began to migrate to other countries.

In January 1958, Jamaica joined a collective West Indian state of nine British territories, the Federation of the West Indies. However, after a national referendum, Jamaica withdrew from the federation and began to negotiate with Britain for independence, which was ultimately granted in 1962. The Jamaica Labor Party (JLP) won the elections and Alexander Bustamente became the prime minister.

Throughout the 1960s, attempts were made to bring foreign manufacturing companies to the country.The companies were given tax breaks, but many implemented racist policies, which gave white workers higher positions. In 1972, the JLP was voted out of office, and the progressive party, PNP, returned, led by Michael Manley.

Manley began a program of democratic socialism. Foreign companies were nationalized and employment policies were revised with blacks gaining higher positions in companies. Education was also funded by the government. Middle- and upper-class residents fled the country, and Jamaica fell into an economic crisis. In 1980, political violence swept throughout the country, and the JLP, led by Edward Seaga regained power. The new government abolished many of the social programs and implemented new strategies to bring in foreign assistance.

The PNP and Manley returned to power in 1989. In 1992, Manley retired and Percival James Patterson became the first black to hold the post of prime minister. Patterson currently remains in this position and the Jamaica government continues to attempt to revive the poor economy and end the rising unemployment throughout the country.

Jakota Triangle

THE JAKOTA TRIANGLE is an East Asian region comprising three countries: JAPAN, SOUTH KOREA, and TAIWAN. The concept originated with Harm de Blij and it has become popularized in the many editions of Geography: Realms, Regions and Concepts, first appearing in the 8th edition, published in 1997. The term triangle was inspired by the three-sided figure defined by the three capital cities of the region: TOKYO, Seoul and Taipei. But the Jakota triangle is unified by more than its three-cornered geometry. This group of East Asian states shares high population density, a high level of urbanization, rapid growth in manufacturing in spite of its dependence on imported raw materials, and lingering geopolitical problems that may be traced to the end of World War II.

The Jakota Triangle is distinctive for its high average population density. Yet each of the three member countries has a rugged and sparsely settled interior: Japan’s 60 active volcanoes are legendary, most notable of which is Mount Fuji, a snow-capped stratovolcano rising to 12,388 ft (3,776 m). The eastern side of the Korean peninsula is dominated by the desolate spine formed by the Taebaek Mountains (Taebaek Sanmaek), just as the most conspicuous physiographic feature of eastern Taiwan is the Chungyang Mountains, which rise to 13,114 ft (3,997 m) at Yu Shan (also known as Mount Morrison). Thus the population distribution of the Jakota countries is uneven with extremely high densities along fertile coastal plains and river valleys and notable concentrations in massive rapidly growing cities.

The Jakota triangle countries have levels of urbanization ranging from 65 percent in Japan to 80 percent in Korea. This feature makes the region distinct fromthe remainder of East Asia and especially from China, which has less than 40 percent of its population in urban areas.

Tokyo, Seoul, and Taipei are massive primate cities; each is well over twice the size of the second largest urban center in the country and each accounts for about one-quarter of its nation’s total population. Tokyo is the largest metropolitan area on the planet with a population of 35 million. Seoul is approaching megacity status with a population of 9.7 million, while Taiwan’s capital is smaller with 6.5 million. The primate city dominance of the Jakota countries extends to their pivotal role as centers of political and financial power and leadership in industrial technology. The Jakota triangle countries are also distinguished by the massive size and rapid growth of their manufacturing sectors, energy-intensive heavy manufacturing such as primary iron and steel and shipbuilding, labor intensive light manufacturing such as textiles and garments, and traditional handicrafts such as paper, wood, and ceramic products. Just as notable has been the explosive growth in Jakota exports of manufactured goods.

Japan is now the world’s second-largest manufacturing economy (after the UNITED STATES), while South Korea ranks seventh and Taiwan is in twelfth place. These nations are globally competitive because they have developed leading-edge manufacturing technologies and have highly skilled workers, an extremely low-cost structure, and aggressively entrepreneurial firms that are striving for world dominance in their industrial specialties. But surprisingly the Jakota countries have achieved these industrial wonders with a modest resource base, and they remain highly dependent on imports of raw materials such as energy, minerals, agricultural commodities, and forest products.

Jakarta

JAKARTA, LOCATED on the island of JAVA, is the capital of INDONESIA and serves as a gateway to the country. Java is located in a chain of islands, with SUMATRA to the northwest, Bali to the east, BORNEO to the northeast, and CHRISTMAS ISLAND to the south. It is the world’s 13th-largest island.

The huge city of Jakarta covers more than 410 square mi (650 square km) and has a population of over 9 million people. Besides serving as government headquarters, Jakarta is the center of Indonesian business and industry. Jakarta is different from other cities in Indonesia because it has the status of a province and its government is administered by a governor rather than a mayor.

Jakarta has a colorful history. As the port of Sunda Kalapa, it was the last Hindu kingdom in the area when the Portuguese arrived in 1522 to take advantage of the spice trade. Their tenure was short-lived, as they were driven out in 1527 by the Muslim leader Sunan Ganugjati. He named the city Jaykarta, meaning “City of Great Victory.” By the early 17th century, both English and Dutch merchants were in the area. When the Dutch took over Indonesia, they changed the name to Batavia. In World War II, the Japanese captured the city and changed its name to Jakarta, mainly to gain the sympathy of the Indonesians. When the war ended and Indonesia gained its freedom, the name Jakarta was retained.

The city has a definite cosmopolitan flavor and diverse culture. Jakarta attracts many immigrants whose cultures have contributed to the overall lifestyle of the city. The Taman Mini Indonesia Indah (Beautiful Indonesia in Miniature Park) pays tribute to the cultures of Indonesia’s 27 provinces. The 250-acre (100-hectare) park is Jakarta’s most visited attraction. 

Jakarta’s major problems are the result of the rapid growth of the city in the past 40 years. During that time, the population has skyrocketed from 2.7 million to over 9 million. The government has not been able to provide for the basic needs of its residents. Jakarta suffers from floods during the wet season, when sewage pipes and waterways become clogged with debris. The depletion of the RAINFOREST on the hills south of the city has also contributed to flooding.

About a third of Jakarta’s population lives in abject poverty, many in squalid settlements made up of huts with earthen floors. They eke out a meager living by selling cigarettes, shining shoes, and scavenging food. The heat and smog of the city make it a hard existence. Traffic in Jakarta is horrendous, with motorcycles, three-wheeled taxis, dented buses, and pedicabs jockeying for position. Residents and tourists spend countless hours stuck in traffic jams. In an attempt to reduce traffic jams, some major roads now allow only cars with at least three people to be operated during rush hour. Other forms of transportation include railroads. Two monorail systems are being built, and the government is considering a network of water buses along the canals of Jakarta.

Italy

ITALY, IN SOUTHWESTERN Europe, is a peninsula bordered by FRANCE to the northwest, SWITZERLAND to the north, SLOVENIA to the northeast, the ADRIATIC SEA to the east, the Ionian Sea to the south, and the Tyrrhenian Sea to the west; its famous boot shape juts into the MEDITERRANEAN SEA. In both its physical and human geographic expressions, Italy presents a distinct and immediately recognizable character. Italy’s landscape has provided the scene for the Roman republic and empire, and its peninsular form has opened it to commerce, culture, and war. 

The geography of Italy colored the background of Renaissance art and has been the setting for fragmented city-states and a unified state. The geography of Italy today is a rich story of a people and a land that not only coexist but that are strongly tied together by history and opportunity. Italy occupies the entirety of a peninsula extending southward from the European continent into the Mediterranean Sea, in addition to two large—and many small—islands. The Italian (or Apennine) peninsula is bounded by the highest crest of the ALPS in the north and northwest. These ranges curve to the south and southeast forming the Apennine ranges which serve as the structural framework of the peninsula. 

Within the curve created by these mountains is the Po River valley, the largest valley on the Mediterranean. Drainage from the mountains fills several large lakes; among them Lakes Como, Maggiore, and Garda in the north and Lakes Trasimeno, Bracciano, and Bolseno in the central part of the country. Surrounding the peninsula, the Mediterranean Sea is divided into several distinct parts: the Adriatic Sea, with Italy to the west and the former Yugoslavia and ALBANIA to the east; the Ionian Sea, between the southern tip of Italy and Greece; the Tyrrhenian Sea to the west of the peninsula containing the large islands of Sicily and Sardinia; and the Ligurian Sea, between the island of Corsica (French) and the northwestern coastline of Italy.

Italy’s climate and weather are typical of Mediterranean climate regimes. The range of temperatures throughout the year is 43 degrees F (24 degrees C) in the north and only 26 degrees F (14 degrees C) in the south. Winter temperatures in the north can average below freezing, while southern low temperatures can be substantially above that mark. The cooling effects of altitude are felt in the Alpine and Apennine highlands. Rainfall is sufficient for agriculture in most of the country with up to 52 in (1270 cm) at some locations in the north, down to 30 in (76 cm) or less in the south.

The dry summer season extends over at least June, July, and August in the south, and during these periods irrigation can be necessary for agriculture, and increases in population can strain the limited water resources. The Italian landscape is considerably wooded, with 34 percent of the total land area forested; 9.25 percent of the land is engaged in permanent agriculture, while an additional 28 percent of the land is arable. In addition to agricultural potential, Italy’s natural resources include limited supplies of mercury, potash, marble, sulfur, natural gas and crude oil reserves, fish stocks, and coal.

Most of the extreme events that occur in Italy are related to its regional physical geographic characteristics. Heavy rains are associated with landslides and mudflows where steep mountainous terrain predominates and with flooding in river valleys and coastal lowlands. Heavy snowfall in the north can generate conditions suitable for avalanches. Active volcanoes are not uncommon in the south; examples include Mount Etna on Sicily, Mount Vesuvius, and Stromboli.

Many of the smaller islands have been forged from volcanic activity and such activity continues to the present. Earthquakes can accompany volcanic activity and the associated tectonic movement. Land subsidence is of concern in some coastal areas, most notably in the city of Venice on the Adriatic Sea.

The people of Italy are as distinct as their physical geographic environment. Although some of the prevailing demographic trends in Italy are similar to those of the European continent as a whole, there are many elements of Italy’s human geographic character that are wholly unique. In terms of population statistics, Italy has an aging population with a declining rate of natural increase. That is, their death rate is greater than their birth rate, leading to declining population numbers in the absence of immigration. There is, however, substantial immigration into Italy, particularly from Eastern Europe, Africa, and the MIDDLE EAST.

The Italian language—which does not predominate in any other country of the world—is in the Romance group of the Indo-European language family. There are small areas in northern Italy where French, German, and Slovene are the predominant languages. The population is overwhelmingly Catholic, with the VATICAN CITY in Rome as the administrative center of the Catholic Church. There are small Protestant and Jewish communities and a growing Islamic immigrant community.

Politically, Italy has historically been at one time the heart of an empire, at another a loosely connected set of regional fiefdoms, and at still another the victim of fascist totalitarianism. Today, Italy is a democratic republic. The Italian federal government employs a parliamentary system, with a president and a prime minister. Parliament consists of two houses, the senate and the chamber of deputies. There are several dozen active political parties seeking seats in those houses.

There are 20 regional governments with varying amounts of regional autonomy, and a large number of municipal political institutions. Internationally, Italy is a member of the EUROPEAN UNION and of the NORTH ATLANTIC TREATY ORGANIZATION (NATO). Italy was comparatively late in securing African colonies but did so in the case of ERITREA, and in part Ethiopia and Somalia. These colonial claims were lost at the close of World War II, but even so, there are substantial political and economic ties between Italy and Eritrea to this day.

Desertification

In the United Nation’s Convention to Combat Desertification (UNCCD), desertification is defined as “land degradation in arid, semi-arid and dry subhumid areas resulting from various factors, including climatic variations and human activities.” This land degradation is defined as a: … reduction or loss in arid, semi-arid and dry sub-humid areas, of the biological or economic productivity and complexity of rainfed cropland, irrigated cropland, or range, pasture, forest and woodlands resulting from land uses or from a process or combination of processes including processes arising from human activities and habitation patterns, such as soil erosion caused by wind and/or water, deterioration of the physical, chemical and biological or economic properties of soil, and long-term loss of natural vegetation. In a more complex understanding, desertification also involves land-use change in pastoral and agricultural dryland systems, because of environmental pressures.

Many assessments have been conducted on desertification, each as varied as the indicators that they have been based upon. The most recent one is the Land Degradation Assessment in Drylands (LADA) of the Food and Agriculture Organization of the United Nations (FAO). In the World Atlas of Desertification, based on the Global Assessment of Human-induced Soil Degradation (GLASOD): drylands are characterized as the zones having a ratio of average annual precipitation to potential evapotranspiration (P/ETp) between 0.005 and 0.65, which includes semiarid and arid areas. Hyper-arid zones are not part of the United Nations Convention to Combat Desertification (UNCCD) desertification definition because they are presumed to be so dry that human degradation is severely limited, unless irrigation is practiced.

Arable land in north Africa and west Asia is pressured by overgrazing, combined with an extension of cropped area, and by salinization caused by dam and irrigation systems such as in the Nile delta. Dryland degradation is widespread in sub-Saharan Africa, northern China, Australia, northeastern Brazil, and the Caribbean islands; many other dryland areas have experienced damage from deforestation and overgrazing in the drylands.

Also, in Europe, degradation is significant in the southern Mediterranean zone.The complexity of definitions make mapping desertification difficult, but according to 2003 data from the UNCCD and WDA, 70 percent of all cultivated drylands are affected by desertification, and 17 percent are already desertified. 24 billion tons of topsoil is lost every year to desertification, which affects the livelihoods of 250 million people. Only 22 percent of global drylands have degraded soils; this figure increases to 70 percent when vegetation degradation is added.

The dryland subtype that is most degraded is the arid subtype, whereas in regions with smaller overall dryland area, the semiarid drylands (the Americas), or the dry subhumid areas (Europe), are the most degraded, respectively. However, within these data it is also difficult to distinguish between states and processes. Africa is particularly vulnerable, with around 60 percent of its total area covered by desert or drylands. The United Nations Environment Programme (UNEP) notes that the extent of desertification is increasing worldwide: “desertification currently affects approximately 25 to 30 percent of the world’s land surface area. About 1.2 billion people in at least 100 states are at risk.”

Link to Climate Change

Climate-simulation models indicate substantial future increases in soil erosion. Desertification will be exacerbated by reductions in average annual rainfall and increased evapotranspiration, especially in soils that have low levels of biological activity, organic matter, and aggregate stability. Desertification and climate can form a feedback loop, with the loss of vegetation caused by desertification reducing carbon sinks and increasing emissions from biodegrading plants.

Soil degradation begins with removal of vegetation. Unprotected, dry soil surfaces are readily eroded by rain and wind, leaving infertile lower soil layers that bake in the sun and become an unproductive hardpan. Sand dunes may form where the blown surface material accumulates. Water is a defining constraint of the drylands. Drought avoidance and coping strategies are imperative, such as choosing drought-tolerant crops, low plant densities, water conservation, and water harvesting. While water shortage is a constant concern, much of the water that is available is not efficiently used. In the Sahel, degraded soils often exhibit impeded water infiltration, so much is lost as runoff.

Given the uncertainty in the models, some models still project other outcomes, such as the regreening of the Sahel zone. Nevertheless, a loss of vegetative productivity can lead to long-term declines in agricultural yields, livestock yields, plant standing biomass and plant biodiversity—changes that reduce the ability of the land to support people. Before, even in adverse areas, people in drylands were able to cope with the cycles of droughts without depleting soils. Now, with the extension of droughts because of climate change, these systems are vulnerable to breakdown, often sparking an exodus of rural people to urban areas. Breaking the strong connection of people to the land produces profound changes in social structure, cultural identity, and political stability.

Desertification also impacts remote areas, and has silted-up rivers and retreated lake surfaces far away from its origin. Since the early 1950s, 670,000 ha. of arable land and 2.35 million ha. of rangeland, steppe, and grassland were invaded by shifting sands. Dust storms created as a result of destroyed vegetative cover led to air quality problems and acid rain elsewhere.

Dangerous Anthropogenic Interference

Dangerous anthropogenic interference refers to scientific estimates of the level of human impacts on the environment that will result in changes, such as global warming, to the point of devastating consequences for the planet and its inhabitants. Scientists and governments have used a variety of models, tools, and data to determine levels of dangerous anthropogenic interference.

Although there is no clear definition of dangerous anthropogenic interference, international studies such as those conducted by the United Nations (UN) Intergovernmental Panel on Climate Change (IPCC) mark the level of dangerous anthropogenic interference between a 1.8 to 5.4 degree F (1 to 3 degree C) rise in the global mean temperature above pre-industrial levels. Although historical human actions have been implicated in a degree of impact on global warming, scientists, governments, and industries have implemented various strategies to reduce or avoid additional dangerous anthropogenic interference for the future.

Scientists began seeking methods of determing the risks of climate change and global warming and their associated impacts as these issues became a growing concern in the late 20th century. Global warming involves increases in the Earth’s global mean temperature. One of the leading sources of dangerous anthropogenic interference and global warming is the emission of greenhouse gases (GHGs). Sources of GHG emissions include the combustion of fossil fuels such as coal, oil, and natural gas, increased use of agricultural fertilizers, growing world populations and subsequent energy and food demands, and land use changes and deforestation.

No Clear Definition or Agreement

There is a lack of a clear definition of dangerous anthropogenic interference among scientists, governments, and nongovernmental organizations (NGOs), as well as a lack of agreement on how it should be prevented. Factors taken into consideration when defining dangerous anthropogenic interference include economic, political, ethical, and scientific concerns. Political and ethical considerations include identifying who will be most impacted by climate change and reduction efforts, as risks and benefits will not be equally shared across the globe. Economic considerations include cost-benefit analyses of methods to prevent or reduce dangerous anthropogenic interference. Scientific factors include historical and current emissions data, forecast models, and the problem of uncertainties in data collection and assessment.

Scientists estimate that temperatures in the

northern polar region are increasing at a faster

rate than the global mean temperature. The use

of aerosols and resulting air pollution presents a

problem in the determination of climate change

and dangerous anthropogenic interference levels.

Aerosol emissions mask GHG warming by raising

levels of incoming solar radiation that is reflected

back to space, known as the albedo. Scientists refer

to this phenomenon as radiative or GHG forcing,

or the aerosol cooling effect. As international

regulations and national air pollution legislation

phase out aerosol use, scientists will gradually

understand the levels of the cooling effect as GHG

levels rise. Greenhouse gases, however, remain in

the atmosphere for much longer periods of time

than aerosols. Scientists also estimate the degree of

global warming that will occur because of historical

emissions that cannot be avoided.

The levels of climate change risk and dangerous

anthropogenic interference have been increased

in the 21st century, as previously hypothetical

impacts of such changes have been scientifically

observed. Many scientists and international agreements

mark the level of dangerous anthropogenic

interference at between a 1.8 to 5.4 degree F (1 to

3 degree C) rise in the global mean temperature

above pre-industrial levels, with some estimates

as high as 9 degrees F (5 degrees C). The IPCC

has estimated this committed warming level to be

4.3 degrees F (2.4 degrees C), with approximately

0.6 degree C already realized. These increased

estimates have also raised estimates of how much

time it will take before various levels of dangerous

anthropogenic interference occur.

Equatorial Undercurrent

The Equatorial Undercurrent (EU) is a strong subsurface equatorial eastward jet, which is situated under the surface westward South Equatorial Current in the Atlantic, Indian, and Pacific oceans. The main EU core (in which velocity exceeds 20 in. [50 cm] per second) occurs within an equatorial thermocline. The EU width is about 260 mi. (~420 km, plus or minus 2 degrees to the north and south from the equator). The thickness of the EU varies from 650 to 1,300 ft. (~200 to 400 m). Typical maximum velocity within the EU core is about 3.3–5 ft. (1 to 1.5 m) per second.

There are two principal reasons for EU, namely the southeast trade wind blowing over the equatorial zone and the convergence of equatorial eastward nonlinear jet. Long-term southeast trade wind forcing, as shown by George Philander, leads to a pressure gradient directed from western boundaries of the oceans to the east. Convergence of eastward nonlinear current at the equator (because of a change in the sign of Coriolis force between the Northern and Southern Hemispheres) causes the generation of a strong narrow undercurrent in the vicinity of the equator.

EU intensity is at a maximum in the Pacific Ocean (where it is called the Cromwell current, in memory of an American oceanographer). Maximum velocity of EU exceeds 60 in. (~150 cm) per second there. In the Atlantic Ocean (where it is sometimes called the Lomonosov current, in memory of Russian vessel Michael Lomonosov, which discovered the Atlantic EU), its velocity is about half that of the Cromwell current. In the Indian Ocean, the EU as a strong subsurface equatorial jet does not exist throughout the year. It occurs in boreal winter, when northeast monsoons are developing, and disappears in summer during the southwest monsoon action.

The EU is situated deeper on the western side of the Atlantic and Pacific oceans because thermocline deepens, only there, as a result of the longterm effect of the southeast trade wind. The depth of the EU core is up to 820 ft. (~250 m) in the western equatorial Pacific. To the east, the EU becomes shallower and more intense. Maximum EU velocity occurs in the mid-equatorial oceans. Further to the east, the EU shallows as well, but its intensity decreases. EU weakening in the western and eastern sides of the equatorial basins is because of intensified horizontal mixing there, restricting its velocity. Often, there is a secondary (deep) core of EU that is mostly because of a barotropic eastward pressure gradient alone the equator. However, the eastward velocity within this core does not usually exceed 8–12 in. (20–30 cm) per second.

Total transport of EU is about 50 Sverdrups in the central equatorial Pacific, while it is about 30 Sverdrups in the central equatorial Atlantic (1 Sverdrup = 106 cu. m per second). This transport is at a maximum in boreal spring (in the Pacific Ocean) and in fall (in the Atlantic). Such phase differences of seasonal cycle between two oceans is because of their different sizes. As was shown by Vitaly Bubnov in his comprehensive monograph, a seasonal EU cycle in the equatorial Atlantic is approximately in phase with southeast trade wind forcing (in accuracy of a month), while in the equatorial Pacific they are approximately out of phase as a result of different sizes and, hence, different equilibrium time.

Abrupt forcing of the equatorial ocean (e.g., before El Niño, when trade winds weaken very quickly) generates different classes of equatorially trapped waves (such as Kelvin, Rossby, inertia- gravitational, and mixed Rossby-gravitational [or Yanai] waves), most of them modified by EU. Low-frequency (decadal-to-decade) variability of southeast trade winds generates quasi-equilibrium EU variations. More or less intense southeast trade winds lead to more or less intense EU. As was shown by Albert Semtner and William Holland, the EU becomes unstable if its velocity exceeds 40 in. (~100 cm) per second. As a result of instability, long planetary equatorial waves are generated. Their periodicity is about 30 days, while wave length is about 500 mi. (~800 km).

Equatorial Countercurrent

Equatorial countercurrents are major surface flows that carry water eastward in the Atlantic, Indian, and Pacific oceans. They are located near the equator and are sandwiched between two westward-flowing currents, the North Equatorial Current and the South Equatorial Current. Equatorial countercurrents are unique, in that they flow in the opposite direction of the surface winds. The other major surface currents in the tropics flow in the same direction as the prevailing winds. 

The equatorial countercurrents are driven by a distinct surface wind pattern in the tropics. Strong westward trade winds result in westward surface flow in most of the tropical Atlantic and Pacific oceans. However, several hundred mi. (km) north of the equator, the winds are much weaker. The stronger winds to the south pile up water where the winds are weak. As a result, the surface of the ocean can be up to 6 in. (15 cm) higher and the thermocline (region of strongest decrease of temperature with increasing depth) as much as 328 ft. (100 m) deeper than it is directly to the north. The excess water flows eastward under the influence of the Earth’s rotation, giving rise to the equatorial countercurrents. In the Indian Ocean, the equatorial countercurrent is located several hundred miles south of the equator, but is caused by a similar mechanism. In all three oceans, the equatorial countercurrent is concentrated in the upper 656 ft. (200 m) above the thermocline.

The intensity of the equatorial countercurrent varies from season to season and from month to month. The strongest seasonal changes occur in the Atlantic Ocean. Eastward flow reaches a maximum in the summer and fall, with speeds of up to 12 in. (30 cm) per second, and disappears in the spring. Seasonal changes are weaker in the Pacific Ocean. Here, the equatorial countercurrent exists year-round, and is strongest in the fall and winter, with speeds slightly greater than those in the Atlantic. In both the Pacific and Atlantic, the equatorial countercurrent is located farthest north in the fall, centered near 8 degrees north. In the Indian Ocean, the countercurrent is present only during the winter.

There are large month-to-month changes in the strengths of the Pacific and Atlantic equatorial countercurrents. The changes are most pronounced during fall in the Pacific, and during summer in the Atlantic, and are associated with clockwise rotating eddies centered between the equatorial countercurrent and the South Equatorial Current to the south. The eddies move westward, driven by the contrast in temperature and flow between the equatorial countercurrent and the South Equatorial Current. Over an entire season, they act to decrease the strength and temperature of the equatorial countercurrent.

The equatorial countercurrent plays an important role in the circulation of mass, heat, and salt in the tropical oceans. It provides one of the pathways through which warm surface water returns eastward after being transported westward in the South Equatorial Current. In the Atlantic Ocean, the equatorial countercurrent also transports significant amounts of freshwater eastward from the mouth of the Amazon River. The Amazon water transported eastward decreases the surface salinity of the western tropical Atlantic Ocean. The strength of the Pacific equatorial countercurrent changes during alternating cycles of El Niño and La Niña. During La Niña, the Equatorial Countercurrent increases in strength, along with an intensification of the other major equatorial currents in the equatorial Pacific. The equatorial countercurrent becomes weaker during El Niño.

Energy Balance Models

Energy balance models represent the First Law of Thermodynamics applied to a system. In climatology, energy balance models are used for the Earth-atmosphere system. This is a closed thermodynamic system because it does not exchange matter with the surrounding environment or space.

Energy balance models can be applied to the Earthatmosphere systems for different timescales, such as a year, day, or hour. Depending on the timescale, the models would produce an annual, daily, or hourly temperature of the Earth-atmosphere system. Also, the energy transfer processes, the energy cycle, could be either steady-state or transient processes. For steady-state models, the energy input is equal to the energy output in the system, resulting in a steady temperature that does not change with time. This assumption is simple, and results in an energy balance model that can be easily solved. More complex models use transient assumptions and give more informative results, but their solution requires numerical simulations.

The simplest energy balance models assume that the incoming solar radiation, called the solar constant, is equal to the radiative energy lost by the Earth-atmosphere system over the period of one year. These simple balance models can calculate an average constant temperature, and cannot account for the climatic shift defined by the change of the Earth-atmosphere temperature. 

To study more realistic natural problems, these models can take into account more complicated energy-transfer processes, such as thermal storage of the energy in the upper layer of the ocean, which makes the model inherently transient. Another modeling improvement includes atmospheric energy transfer by convection and radiation. These models enable studies of the climatic shift by decoupling the incoming solar radiation, forcing, climatic shift, and response. 

In terms of spatial distribution, the simplest are zero-dimensional models that assume the Earthatmosphere system to be a single, uniform point. Dividing the Earth-atmosphere system into zones can refine this assumption. One-dimensional models divide the system into latitude zones to allow for latitude-dependent solar flux, albedo, and emissivity. Two-dimensional models create zones in both latitudinal and longitudinal directions.

Energy balance models can be coupled with mass balance models for the atmospheric air and species conservation models for particulate matter or CO2. These comprehensive models are called global climate models (GCM). With GCMs, the calculations become much more numerically complex, and provide results for weather forecasting and climate change predictions.

Ekman Layer

The Ekman layer (EL) is boundary near-surface layer in the low troposphere and upper ocean, in which the vertical turbulent friction plays a crucial role in the balance of governing forces. Ekman transport is to the right or left of the wind in the Northern or Southern Hemisphere, respectively. This causes upwelling along the equator and certain coastlines.

As V. W. Ekman showed in his classic 1905 paper, “On the Influence of the Earth’s Rotation on Ocean Currents,” the basic steady balance within the EL (in the ocean where depth can be considered infinite) occurs between vertical friction and the Coriolis force. Such balance leads to the generation of the Ekman spiral of drift current (wind). This spiral is a result of turning and weakening of the Ekman current (or wind) to the depth (upper boundary of the EL in the atmosphere).

The vector of Ekman current (wind) is rotating clockwise/anticlockwise to the depth (in the atmospheric boundary layer) in the Northern and Southern Hemisphere. The angle between vectors of surface Ekman current and surface wind is equal to 45 degrees, if the coefficient of vertical turbulent exchange (mixing) does not depend on the depth, as was postulated in the classic Ekman theory. In fact, this angle is usually close to 30 degrees because the coefficient of vertical turbulent mixing decreases to the depth.

In the deep ocean, EL thickness (or Ekman scale) is determined as a depth, where the current direction is opposite to the surface direction. Speed of drift current at the low boundary of EL is smaller than surface speed by eπ times. Thickness of EL in the homogeneous fluid (gas) is controlled by two parameters: (1) turbulent stress (or dynamic velocity depending on the wind speed) at the sea surface, and (2) Coriolis parameter. Wind in the mid-latitudes, of which the speed is about 33 ft. (10 m) per second, generates the surface drift current of about 12 in. (30 cm) per second. The corresponding Ekman scale is about 98 ft. (30 m).

In the ocean at intermediate depth (ocean depth and Ekman scale are the same order), the Ekman spiral is modified, and rotation of current vector to the depth decreases. Typical temporal scale of steady Ekman spiral development is equal to local inertial period. For instance, classic Ekman balance in the mid-latitude interior of the upper ocean is established in about one day after the beginning of wind forcing.

There is also a bottom EL in the ocean, which should be taken into account in the global circulation models if the ocean’s depth is not too large in comparison with the Ekman scale, or for super high-resolved models with a typical size of the vertical grid in the bottom layer of about 33 ft. (10 m). Special care should be taken for the case of a shallow sea, where the depth is much smaller than the Ekman scale. In this case, surface and bottom ELs create a unique EL in which turbulence is well developed, while the Coriolis term is small. As a result, the rotation of drift current to the depth is negligible, and directions of surface wind and drift current in the shallow ocean coincide.

From comprehensive analysis provided by Eric Kraus, Andrey Monin, and Alexander Yaglom, it has been shown that in the stratified fluid (gas), a depth of mixed turbulized layer may be much smaller than EL thickness because turbulent stress is working against buoyancy force. In this case, profile of velocity within the mixed layer looks like a drift current in the shallow sea. Transport of drift (Ekman) current in the ocean’s interior (i.e., in the deep ocean) does not depend on the coefficient of vertical turbulent exchange. It can be calculated quite accurately if the surface wind stress and latitude of the area is known. For instance, based on the assessment by Eric Kraus and Sid Levitus, integral meridional volume transport of drift current across a latitude circle in the world ocean associated with the trade winds reaches about 50 Sverdrups (1 Sverdrup = 106 cu. m per second) and accounts for a significant proportion of meridional overturning circulation within the tropics and at the boundary between tropics and subtropics.

Ecosystems

Ecosystems are defined as communities that involve dynamic interactions among living elements (such as animals, plants, and microorganisms) and the inanimate elements of their environments. All parts of an ecosystem need to work together to maintain the proper balance of the system, and it is necessary for all ecosystems to function in conjunction to maintain balance.

The term ecosystem was first used in 1930 by Roy Clapham (1904–90), an appointee to the demonstratorship in botany at England’s Oxford University. At the time, Clapham was studying plant ecology under the guidance of Botany Department Chair Arthur Tansley (1871–1955), a pioneer in the field of ecology. Two decades after Clapham and Tansley first articulated the concept of ecosystems, ecologists began including the study of ecosystems as a distinct field of study within the discipline of ecology. Scientists have since identified eight major ecosystems: the temperate forest, tropical rainforests, deserts, grasslands, tundra, taiga, chaparral, and ocean.

An ecosystem may be as small as a tidepool or as large as the Sahara Desert or the Atlantic Ocean. The ecosystems of the tropical forests provide a classic example of the extent of ecosystems. In these forests, thousands of vegetable and animal species that live in the air and on the ground interact with millions of surrounding organisms. Within each ecosystem, the habitat is a physical element that combines the natural and adaptive conditions of particular species. All ecosystems are dynamic. Changes may be temporary in response to outside events such as forest fires or natural disasters, or they may occur according to established cycles.

Commonly occurring factors that affect changing ecosystems are nutrient availability, temperature, light intensity, grazing intensity, and species population density. Six ecosystems are identified as most necessary for supporting life on Earth; agroecosystems, forest ecosystems, freshwater ecosystems, grassland ecosystems, coastal ecosystems, and urban ecosystems. The integral relationship between these ecosystems and human life is demonstrated by the fact that half of the world’s jobs are dependent on agriculture, forestry, and fishing. In the poorest sections of the world, 70 percent of all jobs are derived from these industries.

Ecological Footprint

The ecological footprint is a metaphor for ecological impact, regardless of where that impact occurs. The ecological footprint is also an ecological accounting tool, a measure of the environmental impact of consumption and subsequent waste discharge. Consumption items are divided into food, shelter, transportation, and consumer goods and services. The consumption impact is measured by converting impact variables into the single unit of land, measured in hectares or acres. This includes land appropriated by fossil energy use, the built environment, gardens, cropland, pasture, managed forest, and land of limited availability, including untouched forests and nonproductive areas, such as deserts and icecaps. The major strength of the ecological footprint as a way of measuring the sustainability of cities is that it enables a picture of the flow of materials into and out of the city.

Bill Rees and his students, particularly Mathis Wackernagel, developed the concept of ecological footprints (EFs) as a way of ascertaining sustainability at the University of British Columbia in Vancouver, Canada. Most analyses of sustainability, whether radical or mainstream, recognize that major concentrations of human consumption generate impacts far beyond a nation or city’s formal boundaries. Prior to the invention of the concept of EFs, very few policy, lobby group, or academic analyses successfully moved beyond highlighting these external impacts as issues that needed to be addressed. Ecological footprint analysis managed to put forward a way of both measuring and vividly demonstrating how ecological impacts extend far beyond the official area of cities or countries.

The EF approach is similar to the idea of “ghost acres” developed by the Swedish academic Georg Borgstrom in 1965. The focus of Borgstrom’s work was adequate nutrition for a growing population. The ghost acres were comprised of fish acreage and trade acreage. Jim MacNeill and colleagues extended the concept in the lead-up to the Earth Summit in Rio de Janeiro in 1992. The metaphor of ghost acres for food production was extended to include other consumption concerns, and repackaged as “shadow ecologies.” More recently, William Catton discussed the idea of “phantom land.”

This concept refers to how humans currently use the ecological productivity of ecosystems that no longer exist. For example, nature cannot replace fossil fuels such as coal and oil at the rate that humans are diminishing the stock of nonrenewable resources. The goal of ecological footprints is to document “overshoot,” which refers to the excess global demand over global supply, of nature’s resources for human use. Since the original EF methodology was developed, a number of different approaches have emerged. At the Footprints Forum in Siena, Italy, in June 2006, an international standard for footprinting was introduced to ensure consistency. This standard was divided into application standards and communication standards. Standard number 15 attempts to clarify the relationship between EFs and sustainability; that ecological footprinting is a necessary criterion for sustainability, but it is not an absolute indicator of sustainability.

This point is crucial because the EF is a tool that may be used to inform choices and policy development, but it is not a predictive tool, nor can it be a surrogate for environmental policy. Although the national scale is used as a benchmark in the 2006 Footprint Standards, the EF approach can be used at a variety of scales that have been labeled sub-national. These include cities, regions, states, counties, and organizations. In the case of a city, the approach can be used to calculate the equivalent amount of land consumed for a city to function. This equivalent amount of land is influenced by changes in both population and per capita material consumption.

Earthshine

The World Book defines albedo as “the ratio of light reflected to light received by a planet or other heavenly body.” Earthshine arises from sunlight reflected from the Earth to the dark of the moon and back to the nighttime Earth. The albedo is because of the Earth’s cloud cover and the diversity of landscapes. Leonardo da Vinci (1452–1519) first explained Earthshine in the 15th century. A simple technique was developed to measure the amount of sunlight that bounces off the Earth’s surface and is subsequently reflected by the moon. Earthshine is faintly visible to the naked eye on the darker side of the crescent moon as an ashen glow. For many phases of the moon, Earthshine is easily visible by the naked eye.

André-Louis Danjon (1890–1967) performed the first rigorous Earthshine measurements in 1926. He captured 200 data points over a period of five years with his cat’s eye photometer, and using a technique he pioneered called the Danjon scale. Danjon found that it was important to take the measurements well after and well before a full moon or a new moon. Having an even area of bright and dim light when observing the moon’s surface is needed to gain an accurate reading of Earthshine. After then, few measurements were taken, until NASA funded Project Earthshine in the 1990s to obtain albedo numbers. A value of 0.297 was obtained from the study. The research team used a 6 in. refractor telescope housed at California’s Big Bear Solar Observatory. Earth’s albedo decreased 2.5 percent during a period of five years. Satellite measurement of solar irradiance reported a variation of no more than 0.1 percent during an entire 11-year solar cycle. Some experts believe that this deviation is too small to change climate or leave a terrestrial footprint of the solar activity cycle. Thus, Earth’s reflectivity may be what is magnified in an indirect role of the sun in climate change. If this ability to reflect light is degraded, by even as little as 1 percent, global warming could be accelerated.

Earthshine measurements using low-power Earth-bound telescopes are practical since they are cost-effective, easy to conduct, and immediately cover a large portion of the Earth’s surface. Satellite determinations of the albedo, however, are costly and require precise calibration to obtain good results. In addition to capturing measurements when there is a clearly defined moon crescent, it is important to average a large number of data points. This is to remove the effects of a single measurement location where a nighttime measurement would see more light reflected by a large landmass on the opposite side of the planet, or where less light would be reflected by an ocean. This process of averaging provides a more accurate reading of a changing albedo. Modern techniques enable a measurement accuracy of 2 percent for each reading, which is equivalent to measuring Earth’s emission temperature to within 0.8 of a degree C.

Earth’s cloud cover dominates the “shininess” feature of the planet. Clouds reflect around 50 percent of incoming sunlight. Snow and ice reflect even more sunlight, usually from 50 and 90 percent. The melting of polar ice and disappearance of Greenland’s ice cover leaves more water, which reflects only 8 percent of sunlight, and uncovers more land, which is also a poor reflector of sunlight, usually with a reflectivity of 10–25 percent. The darker the surface, the lower the albedo, and the more solar energy absorbed. The dark side of the moon usually refers to the side of the moon that the human eye cannot see from Earth, even with the aid of a telescope. In the controversial world of climate change and the use of Earthshine as a tool to gauge global warming, the dark side of the moon now refers to the dim side of the moon in its crescent configuration. The moon’s surface provides astronomers and climatologists another means for measuring both sunshine and Earthshine, and to assess the global warming phenomenon.

Foraminifera

Foraminifera are marine eukaryotic unicellular organisms that construct a shell or test. They use chemicals from their surroundings to construct calcareous or siliceous crystals, or particulate grains to form an agglutinated test. They are heterotrophic protoctists with granular reticulopods (pseudopodial networks) exhibiting two-way streaming. Foraminifers are Linnean classified by their chemistry, mineralogy, structure of the test walls, cytology, and DNA of protoplasm.

Foraminifers can be either benthic or planktonic.

Benthic foraminifers, in the shape of simple agglutinated tubes, lived in the Cambrian (500 million years ago). Planktonic foraminifers appear in the fossil record during the Jurassic (206 million years ago). Both variants provide excellent fossil records and are the most diverse group of shelled marine microorganisms on Earth. Most live in specific environments and cannot survive drastic environment changes. Most foraminifers evolve relatively quickly and only range in the geological record for a short time (approximately 105 years), making them useful for developing theories on evolution, origination, extinction, and biogeographic distribution of past and present environments projected into the future.

The ecological controls on foraminifers depend on if they are bathyal-abyssal open ocean or shallow-water foraminifers. Benthic foraminifers are affected by the input of organic matter and other food sources from the surface layer 328 ft. (100 m), amount of available oxygen, sediment influx, and seafloor currents, salinity, and temperature. Benthic foraminifers are used to evaluate surface productivity in the ocean. Controls on planktonic foraminifers include salinity, temperature, upwelling, and the productivity of the surface layer. Planktonic foraminifers are used to reconstruct ocean currents, circulation, paleotemperatures, and large-scale shifts in Earth’s surface thermal regime.

Stable oxygen and carbon isotopes, as well as trace elements taken up in tests of foraminifers, are used reconstruct gross past climate trends and temperature cycles. Foraminifers are sampled from marine sediment cores from around the globe. They are correlated with the magnetic stratigraphy and biostratigraphy of other microfossil groups among the Atlantic, Pacific, Indian, and Arctic oceans. Oxygen and carbon in biogenic carbonates are determined by the mass ratios of CO2. 16O and 18O for foraminifers are used for fractionation comparison. δ18O in seawater is linked to the hydrologic cycle (evaporation, atmospheric vapor transport, freshwater return to the oceans by precipitation, runoff or melting of icebergs, and long-term storage in aquifers and ice sheets).

Lighter isotopes evaporate first and precipitate last. Therefore, the farther the precipitation occurs from source waters, the more depleted in 18O the vapor becomes. Temperature and salinity can be deduced from 18O values. There are many factors that affect the fractionation of oxygen in foraminifer tests, including ontogenics, symbiotic photosynthesis, respiration, gametogenic calcite, and carbonate ion concentrations. All of these factors need to be taken into account when interpreting

δ18O in planktonic foraminifers and sometimes in benthic foraminifers.

Carbon isotopes are derived from organic matter and sediment carbonate reservoirs. Surface waters are enriched in 13C because of the fractionation that occurs in photosynthesis. In deep water, δ13C is controlled by the amount of organic decay, time of exposure at the sea floor, and rate of decay of organic matter. Change in depth of calcification of foraminifers is also recorded. 

Trace elements are also used to reconstruct past oceanic conditions, providing independent validation of other proxies such as stable isotope values and ratios. The calcite test of a foraminifer is composed of 99 percent CaCO3, with the remainder comprised of trace elements. The composition of a test reflects seawater composition and the biological and physical conditions of the environment. Paleotemperature proxies (Mg), seawater nutrients, carbon and carbonate levels (Cd, Ba), physical properties such as temperature and pressure (Mg, Sr, F, B), history of ocean chemistry (Li, U, V, Sr, Nd), and secondary post-depositional processes such as CaCO3 and SiO2 diagenesis (Mn) are combined for the development of paleoceanographic reconstructions.

Istanbul

THE CITY OF ISTANBUL in TURKEY has one of the most interesting and important physical locations of any city in the world, the crossroads of TRADE ROUTES by both water and land. It is the only city to straddle two continents, Europe and Asia, and has been at the center of regional commerce for nearly 3,000 years. As Constantinople, it was the most important city in the Western world after the fall of the Roman Empire in the West and was then transformed into the political center of the OTTOMAN EMPIRE, which dominated the eastern Mediterranean until its demise 1923.

The western bank of the Bosporus, the narrow channel connecting the BLACK SEA and the Sea of Marmara, was first settled about 3,000 B.C.E. At its narrowest, the Bosporus is only 2,640 ft (800 m) wide, an ideal location for a settlement to participate in and control any and all trade passing between the Black Sea and the MEDITERRANEAN. Greek colonists established cities on both sides of this channel in the 7th century B.C.E., Chalcedon on the east side, and a city named for one of their early leaders, Byzas, on the west bank.

This city, taking the name Byzantium, was built above the finest natural harbor on the Bosporus, a narrow inlet called the Golden Horn because of its curved shape and the amount of wealth that flowed across its piers. This is the heart of today’s Istanbul and forms the northern boundary of the old city. Called Haliç in Turkish, and Keration in Greek, the six-mile-long Golden Horn dominated shipping then, as it does today. The city grew wealthy by charging tolls from any ship passing through the narrows of the Bosporus.

Byzantium remained a fairly minor city until the 4th century C.E., when Roman emperor Constantine the Great chose the city as his new capital. Constantinople reached the height of its intellectual sophistication and architectural grandeur in the 6th century, under Emperor Justinian, who constructed some of the grandest buildings in the world, including the Church of Hagia Sophia (“Holy Wisdom”), the largest church in Christendom. After nearly eight centuries of continual attacks, Constantinople fell to the Ottoman Turks in 1453 and became the center of Ottoman power in the eastern Mediterranean. While retaining the name Constantinople officially (Qostantiniyeh in Turkish), gradually the city began to be called Istanbul (or Stambul) locally, a corruption from the Greek words for “to the city.” It was also sometimes known to the Turks as Dersaadet, “Abode of Felicity,” known for its luxurious palaces and lush gardens. The Turkish sultans ruled a city whose climate was indeed felicitous, warm and not too dry, suitable for the extensive gardens that came to dominate much of the old city within the walls, known as the Surici. The city continued to thrive, with a population of about 500,000 in 1500.

Today, Istanbul is the principal city of Turkey, though it ceased to be the capital after the fall of the OTTOMAN EMPIRE in 1923. With a population exceeding 9 million, Istanbul ranks among the top 10 largest cities in the world. Istanbul is the capital of a vilayet (province) of the same name—officially changed from Constantinople only in 1930. The city has three main divisions: Old Istanbul (the city within the ancient and medieval walls), Galata-Beyoglu across the Golden Horn, and the Asian Quarters across the Bosporus. The city is more heterogeneous than the rest of Turkey, with some of its quarters dominated by specific minorities: Greeks, Armenians, and others.

Istanbul proper encompasses a peninsula between the Golden Horn and the Sea of Marmara to the south, from the old wall across the end of the peninsula in the west, to Sarayburnu (Palace Point) in the east. Where once there was a sea wall, Ottoman sultans built several elaborate palaces and gardens, the most famous being the Topkapi Palace, which is today one of the city’s major museums and tourist attractions.

FAMOUS MOSQUES

The terrain for most of the city is very hilly, with mosques and funeral monuments built to crown most of the primary hills: the most famous mosques include Mehmet II and Yeni Cami (New Mosque). The main thoroughfare is the Divan Yolu, from the Hagia Sophia to the Bayezid II Mosque. Other tourist sites include the twin fortresses of Anadolu (“Asia”) and Rumeli (“Europe”) built by the Turks on the shores of the Bosporus just before the conquest and the vast covered markets. The quarter of Eyüp, the supposed site of the tomb of the Prophet Mohammed, was for centuries the site of royal ceremonies and burials.

Galata-Beyoglu, on the northern shore of the Golden Horn, was historically the residence of foreign merchants, and is today the center of modern Istanbul, with its largest shops and hotels. Across the Bosporus lie the Asiatic Quarters connected to the European side by two major suspension bridges. Smaller residential and industrial towns line the Bosporus on both sides, and along the northern edge of the Sea of Marmara, a sector of beach resorts and summer homes.

Israel

THE STATE OF ISRAEL is located on the eastern shore of the MEDITERRANEAN SEA, bordering the Gaza Strip to the southwest, EGYPT to the southwest, the West Bank to the east, JORDAN to the east and southeast, SYRIA to the northwest, and LEBANON to the north. Israel is a parliamentary democracy with the Knesset as the legislature. The president serves as chief of state, while the prime minister serves as the head of government. Hebrew and Arabic serve as the official languages of Israel, but English is widely used as a foreign language. Jerusalem, Tel-Aviv, and Haifa are the major cities.

The landscape of Israel is varied. The coastal plain stretches from Gaza in the south to Haifa in the north, covering 291 mi (469 km). Mountains traverse north to south in the central part of the country. The Sharon Plain stretches from Haifa to the Yarkon River, from which begins the Shefala Plain, which continues through Gaza. The Jordan River is Israel’s main source of water and forms the border with Jordan. The Negev Desert makes up the southern portion of the country. Northern Israel receives average rainfall of 39 in (1,000 mm), while Eilat receives .8 in (20 mm). The country is susceptible to sandstorms during the spring and summer and periodic earthquakes.

Israel was part of the FERTILE CRESCENT that stretched from Mesopotamia. The Hebrew-speaking Semitic people who became the Jews settled in this region 3,500 years ago. A Judean kingdom was founded by King David, which survived until 586 B.C.E. when the Babylonians destroyed the First Temple and Jerusalem and sent part of the population into exile.

Thereafter, the region fell under the sway of Persians, Greeks, Romans, Muslims, Crusaders, and the Turks. In 1897, Theodore Herzl, after witnessing European anti-Semitism, founded a Zionist movement, which called for a Jewish homeland in Palestine. Between 1882 and 1903, Jews from all over Europe settled in Palestine and founded communities. These new settlers faced problems of poor soil, lack of experience, and opposition from Arabs and Turks.

A turning point in the formation of Israel as a modern state came during World War I. When the war

broke out in 1914, the Ottoman government began expelling Jewish settlers in PALESTINE, whom it declared “enemy aliens.” On November 2, 1917, the Balfour Declaration established official British support of a “national home for the Jewish people.” At the end of the war, the OTTOMAN EMPIRE was dismantled, and the League of Nations officially recognized the British Mandate for Palestine. In 1939, with war against Adolf Hitler’s Germany looming, Britain issued the White Paper, which voiced its support for the creation of an Arab state for all of Palestine, barring Jewish emigration to the area.

By February 18, 1947, the British government ended the mandate on Palestine, leaving its fate to be decided by the newly formed United Nations (UN). The new UN Security Council faced the decision of whether to vote on the partition of Palestine into a Jewish and Arab state. As a result of the influence of the United States, the Security Council voted for the partition of Palestine.

On May 14, 1948, David Ben-Gurion declared the independence of the State of Israel. Between 1948 and 1973, Israel fought a series of wars with American support against the Arab states in order to maintain its existence. After the Six Day War in 1967, Israel gained control of the West Bank and East Jerusalem from Jordan; Gaza Strip and the SINAI PENINSULA from Egypt, and the GOLAN HEIGHTS from Syria. After meeting in Camp David in 1977, Prime Minister Menachem Begin of Israel and President Anwar Sadat of Egypt signed the Israeli-Egyptian Peace Treaty in 1979, marking the first time Israel made peace with an Arab state.

Since 1979, there has been a movement toward securing peace between Israel and its Arab neighbors. In 1991, the Madrid Conference called for talks on a final peace settlement. In 1993, through the Oslo accords, Israel and the Palestinians worked toward ending occupation of the West Bank and the Gaza Strip, paving the way for a Palestinian state. In 1994, Israel signed a peace treaty with Jordan. However, by September 2000, renewed hostilities flared between Palestinians and Israel, undermining the gains that had been made toward a permanent settlement. The Israeli population is 80 percent Jewish. Of that percentage, 32 percent is from Europe, while 15 percent is of Asian descent and 13 percent is of African descent. The remainder of Israel’s population is mostly Arab.

Israel has a market economy that includes a significant government role in economic policy. There have been great advances in the increase of agricultural output despite its limited arable land. There has been a significant growth in the technological sector of the economy. The addition of Jews from the former Soviet Union has also revitalized the economy. However, the government has a sizable foreign debt, particularly with the UNITED STATES. Israel’s economic prospects continue to be overshadowed by the uncertainty of the Israeli-Palestinian conflict.

Isphahan

FOR THE LAST 900 years, Isphahan (Isfahan, Esfahan) has been the capital of the province of the same name in the center of the empire that was known as Persia, now IRAN. The city lies in a basin at an altitude of 5,150 ft (1,570 m) above sea level in the foothills of the ZAGROS MOUNTAINS. The region is desert punctuated by numerous oases that were the source of sustenance for the caravans that once traversed central Asia. 

Isphahan is one such oasis that lies on the banks of the Zayandeh River, 272 mi (435 km) from Tehran, Iran’s capital. It is the third-largest city of Iran, with a population of about 1.5 million and was acclaimed as a beautiful city in the 16th century by its inhabitants, whose phrase Esfahan nesf-e Jahan (“Esfahan is half the world”) is frequently repeated today.

Isphahan was founded more than 2,000 years ago and because of its location and resources, it has experienced many invasions and changes of fortune. It was originally known as Aspadana and was an important center in Sassanian times, between 200 and 650 years C.E. It was taken by invading Arabs in the 7th century when Islam was established and when Isphahan became the provincial capital. Four hundred years, later it was annexed by Seljuk Turks when it rose in stature to become the capital of their empire. Like so many cities of central Asia, Isphahan was then captured by the Mongols under Genghis Khan in the 1220s and then by Tamerlane in 1338, when it was reputed that 70,000 people were killed.

Its golden age of artistic and architectural achievement began under Shah Abbas during the period of approximately 1587 to 1621 of the Safavid dynasty, which had been established in Persia in 1502. Mosques, palaces, gardens, and bridges were constructed, carpet making and artistic endeavors were encouraged, and the city increased its wealth. Its population swelled to about 600,000, and it became one of the great metropolises of the time. Its heyday was short-lived, as it was taken by the Afghans in 1723 with much bloodshed. It lost its status as the capital, which was bestowed on Shiraz. Following 200 years of relative peace, Russians occupied Isphahan in 1916.

Modern Isphahan is still dominated by the art and architectural heritage of Shah Abbas. Among the most famous world-class sights are Imam Square, with its bazaars, mosques, and flower gardens; the Friday Mosque, Imam Mosque, and Hakim Mosque; Madraseh-ye Emami and Madrasah-ye Mulla Abdollah; as well as numerous minarets, teahouses, mausoleums, palaces, and museums. They attract visitors from throughout world, and its handicrafts, which include carpets, silver- and copperware, and miniature paintings, are much prized. Its industries also reflect the rich agriculture of its oasis HINTERLAND and its location for trade. Iron and steel production, established in 1971, reflects a degree of industrialization in this rapidly expanding city.

Irrawaddy River

THE IRRAWADDY is the chief river of MYANMAR, or Burma. It is formed from the confluence of the Mali and N’mai rivers far in the northern highlands on the borders with CHINA, and flows 1,350 mi (2,177 km) before entering the Andaman Sea (a section of the BAY OF BENGAL). The river’s extensive DELTA begins about 140 mi (225 km) before it reaches the sea, and splits into nine main channels. It is estimated that the waters of the delta lay down 260 million tons (236 million metric tons) of silt per year.

The capital city of Yangon (Rangoon) is located on one of these delta channels, though not the main river course, located about 70 km (43 mi) to the west. About a dozen large sea inlets form the mouths of the Irrawaddy, spanning roughly 300 km (180 mi) from west to east. The delta is protected by levees for hundreds of kilometers and is one of the chief rice-exporting areas of Southeast Asia, formerly awarding the area the nickname, the “rice bowl of Southeast Asia.”

Steamers can transport goods upstream as far as Bhamo (about 1,000 mi or 1,600 km), nearly to the borders with CHINA’s Yunnan Province. The country’s major oil pipeline follows the course of the river from oilfields near Chauk down to export facilities at Yangon. The river valley dominates the shape of Myanmar, particularly the central historic province of Burma proper, hemmed in by the parallel chains of north to south mountains, called the Pegu Yoma and Shan Highlands in the east, and the Arakan Yoma and Chin Hills in the west.

The country’s other main river, the Salween, also travels through the same sort of north-south valley, though much narrower (and actually for a much greater distance, originating far inside the Chinese border). A third river, the Sittang, while much shorter, is more comparable to the Irrawaddy in its importance as a chief rice-growing area. Most of the Burmese population lives along these valleys, both in the north, around the city of Mandalay, and in the southern delta.

The river, officially spelled Ayeyarwady, can be divided into two main sections, above and below Mandalay. Above this point it is swift and narrow, with several rocky defiles. But just below Mandalay the Irrawaddy joins with its chief confluent, the Chindwin River, and it becomes broad and slow-moving, ranging from 1 to 4 mi (1.5 to 6.5 km) wide. During seasonal floods, however, the currents can be much quicker and hazardous to river traffic. Forests along the river have virtually been eliminated and continue to be cut down at a rate of approximately 2 million acres (800,000 hectares) a year. The Mon River is also a major tributary, with one of the earliest (and largest) dams in the region, built in 1906 and recently renovated, providing extensive irrigation to the upper reaches of the country’s western regions.

As the commercial center of the British colony of Burma, the Irrawaddy River valley attracted numerous commercial wet-rice planters from the 1850s, funded by money lenders from Calcutta (KOLKATA), INDIA, a source of later friction between independent India and Burma. From 1855 to 1930, the area cultivated for rice increased from 988,000 acres (400,000 hectares) to 9.8 million acres (4 million hectares), and the population increased from 1.5 million to 8 million. Production dwindled during decades of socialist rule but is starting to pick up again under programs of economic liberalization and remains the regime’s most important source of foreign revenue.

Today, the river is seen as a unifier of the nation’s diverse ethnic groups who populate its banks—including the Kachin, Shan, and Chin minorities—whose independent spirits frequently threaten to pull the state apart.

Ireland

THE REPUBLIC OF Ireland covers five-sixths of the island of Ireland and shares its only border with Northern Ireland, which is part of the UNITED KINGDOM of Great Britain and Northern Ireland, also known by the historic name of Ulster. Ireland is a republic with a president as head of state and a prime minister as the head of government. Its legislative branch is a bicameral parliament. Ireland is divided into four provinces and 26 counties. English is widely used throughout Ireland, but Gaelic is also spoken along the western coast. Ireland’s major cities are Dublin, Cork, Limerick, Waterford, Galway, Dundalk, and Kilkenny.

Ireland’s terrain is mostly level to rolling interior plain with rugged hills and low mountains. The west coast is studded with sea cliffs, while the east coast of Ireland has few indentations. The central part of Ireland consists of bogs, meadows, and lakes. The chief rivers in Ireland are the Shannon, Boyne, and Blackwater. The temperature ranges from 40 degrees F (4 degrees C) in the winter to 62 degrees F (16 degrees C) in the summer. Ireland receives an average rainfall of 40 in (102 cm) per year.

Human settlement in Ireland goes back more than 10,000 years during the Mesolithic period. Ireland experienced waves of migrations in its early history. The Gaels, who are the ancestors of the modern Irish people, first settled in Ireland in 700 B.C.E. Christianity arrived in Ireland around the third century, although it was through St. Patrick’s missionary efforts between 432 and 465 that it took root, making Ireland a center of Christianity in early medieval Europe.

England began its control of Ireland in the 12th century when Dermott MacMurrough of Leinster sought the assistance of Henry II of England in his battles against other Irish chieftains. The conquest of Ireland was complete in 1541 when Henry VIII was declared king of Ireland by the Irish Parliament following a rebellion. Under the Tudors, England began the “plantations,” which was systematically settling parts of Ireland with English settlers. Ireland was also pulled into the English Civil War and suffered under the resulting rule under Oliver Cromwell in the 17th century.

During the Restoration in 1660 under Charles II, the Irish Catholics were relieved of the persecutions imposed upon them. With the succession of James II in 1685, they were hopeful of having a Catholic on the throne again. Even though James II was deposed during the Glorious Revolution of 1689, Irish Catholics continued to recognize him as their king. In 1690, the forces of King William defeated the forces of James II in the Battle of the Boyne, resulting in the Penal Laws, which not only marginalized Irish Catholics from the political and economic life but also witnessed the rise of an Anglo-Irish elite. Economic conditions under absentee landlords led to the Rebellion of 1798.

Through the Act of Union in 1801, Ireland became part of the United Kingdom of Great Britain and Ireland. By 1829, Irish Catholics benefited from the Catholic Emancipation Act. Between 1845 and 1851 the Great Famine ravaged throughout Ireland, which reduced its population from 8 million in 1845 to 2 million in 1851 due to starvation and emigration. The famine exposed the flaws in the Irish tenure system and British governance. The latter half of the nineteenth century was consumed by the question of home rule for Ireland. Home rule remained an intractable question because Ireland was divided between the Irish Catholics who supported an independent parliament and internal autonomy and Protestants in Ulster who wished to remain loyal to Westminster.

In 1920, after the cataclysm of World War I and a guerrilla war against the British army, the Government of Ireland Act divided Ireland into twenty-six southern counties that were represented by its own parliament in Dublin, and the six counties in Ulster that continued to be represented in Westminster. The Anglo-Irish treaty retained allegiance to the British sovereign and naval bases on the Irish coast. In 1937, the Irish Free State became Eire, which repudiated the Anglo-Irish Treaty of 1921.

During World War II, Eire declared its neutrality, depriving Britain use of naval bases in the southern coast. In 1948, the Republic of Ireland Act severed all ties to Britain, the Empire, and the Commonwealth, while Northern Ireland remained loyal to the Crown. In turn the British parliament passed the Ireland Act, which gave rights to all citizens of the Republic of Ireland who traveled to Britain. With the outbreak of violence in Northern Ireland in 1972, the Republic of Ireland and Britain have since cooperated against the Irish Republican Army and other terrorist groups. In 1973, the Republic of Ireland joined the European Economic Community. In 1998, the Republic of Ireland has been a participant in the Good Friday Agreement, in the resolution of “The Troubles” in Northern Ireland, though efforts have stalled in recent years. In 1999, Ireland adopted the euro as its currency. In 2001, a majority of Irish citizens vetoed the Treaty of Nice because of doubts on the expansion of the EUROPEAN UNION (EU). In 2004, the Republic of Ireland assumed the presidency of the EU, tackling issues such as drafting a new constitution for Europe.

Ireland has had a rapidly growing economy in recent decades, growing at an annual rate of 8 percent between 1995 and 2002. Industry makes up for 38 percent of the GDP, while services account for 49 percent of the gross domestic product. Much of its economic growth was due to its exports in technology, followed by consumer spending, construction, and business investment. Ireland’s chief trading partners are Britain, the UNITED STATES, GERMANY, FRANCE, JAPAN, and the NETHERLANDS.

Intercropping

THE CULTIVATION OF TWO or more crops in combination in the same field at the same time is known as intercropping. This is one of two types of multiple cropping, the other being sequential cropping, whereby two or more crops are grown in sequence in the same field. There are four types of intercropping:

1) Mixed intercropping is the cultivation of two or more crops that are randomly distributed rather than grown in rows. This practice is typical of slash-andburn agriculture, which relies on cutting and firing.

2) Row intercropping involves the cultivation of different crops in adjacent rows. This is typical of agricultural systems with intermediate technology such as plows.

3) Strip intercropping utilizes strips of land rather than narrow rows. Each strip is of sufficient magnitude that it can be cultivated independently, but the width does not preclude interaction between the crops, such as the prevention of disease as individual crops act as barriers. This practice is characteristic of commercial large-scale farming, which is mechanized.

4) Relay intercropping involves the planting of a second crop into a first crop that is partway through its growth but is not yet ready for harvesting. It may incorporate elements of some of the above.

Where a tree crop is present, between the rows of which other crops or grass for fodder are grown, the system is referred to as agroforestry, but it is nevertheless a type of intercropping. There are several advantages to intercropping that relate to socioeconomic factors and environmental factors.

In an economic context, farmers practicing intercropping rarely experience total crop failure and so have a safety net provided by the successful crop(s). Farmers and their families may develop self-sufficiency when they cultivate crops for various purposes such as food, fiber, the feeding of animals and medicines. The practice also facilitates the spread of labor because intercropped species are planted, tended, and harvested at different times. Disadvantages are few but harvesting can be difficult if machinery or special skills are required for the different crops.

The ecological/environmental aspects of intercropping reflect the varied requirements of crop plants for nutrients, shade, light, length of growing season and disease resistance/susceptibility, as well as beneficial relationships with soil flora and fauna. It is, however, essential that an appropriate combination of species is selected. Overall, productivity increases per unit area of land in intercropped systems when compared with monocultural systems.

For example, it is advantageous to grow tall and short crop species—maize (corn) with peanuts or a root crop—especially those with different growing times, in alternate rows, as this reduces competition of light. Or two tall crops may be planted provided they have different growth rates so that they mature at different times. Leguminous crops are also important in intercropping systems because of their association with nitrogen-fixing bacteria that occupy root nodules.

These fix nitrogen from the atmosphere and convert it into nitrates. Once in the soil, these salts benefit all crops and reduce or eliminate the need for costly artificial fertilizers. An example of such an association for agriculture in a temperate environment is maize with oats and soybean, of which the latter is the legume. For a tropical environment, peanut is the legume that is intercropped with sorghum and millet.

Combinations of crops with different nutrient requirements are also desirable in order to utilize the nutrient store in the soil sustainably. In this respect, the crops complement each other and the agricultural system is similar to natural vegetation communities that tend to be diverse with the coexistence of species with complementary environmental requirements. Complementarity replaces competition.

Intercropping generally reduces the outbreak and impact of diseases and pests and so less of the produce is lost in the field. The crop variation appears to favor a wider variety of beneficial insects that prey on pests when compared with monoculture. Rows of crops not preferred by specific insects will act as barriers. Alfalfa, another legume, is especially beneficial in intercropping because it attracts more beneficial insects than most other crops. With careful management, pesticide use can be reduced. The spread of disease, such as fungal and viral pests, can also be limited by such barriers. The maintenance of a crop cover can reduce the incidence of weeds as can the establishment of a good root mat below ground if crops with different root systems are chosen.