global warming

This article is about the effects of global warming and climate change.[2] The effects, or impacts, of climate change may be physical, ecological, social or economic. Evidence of observed climate change includes the instrumental temperature record, rising sea levels, and decreased snow cover in the Northern Hemisphere.[3] According to IPCC (2007a:10), "[most] of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in [human greenhouse gas] concentrations". It is predicted that future climate changes will include further global warming (i.e., an upward trend in global mean temperature), sea level rise, and a probable increase in the frequency of some extreme weather events. Signatories of the United Nations Framework Convention on Climate Change have agreed to implement policies designed to reduce their emissions of greenhouse gases. Overview Global mean surface temperature difference from the average for 1880-2009 Mean surface temperature change for the period 1999 to 2008 relative to the average temperatures from 1940 to 1980 Over the last hundred years or so, the instrumental temperature record has shown a trend in climate of increased global mean temperature, i.e., global warming. Other observed changes include Arctic shrinkage, Arctic methane release, releases of terrestrial carbon from permafrost regions and Arctic methane release in coastal sediments, and sea level rise.[4][5] Global average temperature is predicted to increase over this century, with a probable increase in frequency of some extreme weather events, and changes in rainfall patterns. Moving from global to regional scales, there is increased uncertainty over how climate will change. The probability of warming having unforeseen consequences increases with the rate, magnitude, and duration of climate change.[6] Some of the physical impacts of climate change are irreversible at continental and global scales.[7] With medium confidence, IPCC (2007b:17) concluded that with a global average temperature increase of 1–4°C, (relative to 1990–2000) partial deglaciation of the Greenland ice sheet would occur over a period of centuries to millennia.[8] Including the possible contribution of partial deglaciation of the West Antarctic Ice Sheet, sea level would rise by 4–6 m or more. The impacts of climate change across world population will not be distributed evenly (Smith et al., 2001:957).[9] Some regions and sectors are expected to experience benefits while others will experience costs. With greater levels of warming (greater than 2–3°C by 2100, relative to 1990 temperature levels), it is very likely that benefits will decline and costs increase (IPCC, 2007b:17). Low-latitude and less-developed areas are probably at the greatest risk from climate change (Schneider et al.., 2007:781).[10] With human systems, adaptation potential for climate change impacts is considerable, although the costs of adaptation are largely unknown and potentially large. In a literature assessment, Schneider et al.. (2007:792) concluded, with high confidence, that climate change would likely result in reduced diversity of ecosystems and the extinction of many species. Definition of climate change This article refers to reports produced by the IPCC. In their usage, "climate change" refers to a change in the state of the climate that can be identified by changes in the mean and/or variability of its properties, and that persists for extended periods, typically decades or longer (IPCC, 2007d:30).[11] The climate change referred to may be due to natural causes or the result of human activity. Physical impacts Main article: Physical impacts of climate change This section describes some physical impacts of climate change. For some of these physical impacts, their effect on social and economic systems are also described. Effects on weather Increasing temperature is likely to lead to increasing precipitation [12][13] but the effects on storms are less clear. Extratropical storms partly depend on the temperature gradient, which is predicted to weaken in the northern hemisphere as the polar region warms more than the rest of the hemisphere.[14] Extreme weather See also: Extreme weather, Tropical cyclone#Global warming, and List of Atlantic hurricane records IPCC (2007a:8) predicted that in the future, over most land areas, the frequency of warm spells or heat waves would very likely increase.[3] Other likely changes are listed below: * Increased areas will be affected by drought * There will be increased intense tropical cyclone activity * There will be increased incidences of extreme high sea level (excluding tsunamis) Local climate change Main article: Regional effects of global warming The first recorded South Atlantic hurricane, "Catarina", which hit Brazil in March 2004 Regional effects of global warming vary in nature. Some are the result of a generalised global change, such as rising temperature, resulting in local effects, such as melting ice. In other cases, a change may be related to a change in a particular ocean current or weather system. In such cases, the regional effect may be disproportionate and will not necessarily follow the global trend. There are three major ways in which global warming will make changes to regional climate: melting or forming ice, changing the hydrological cycle (of evaporation and precipitation) and changing currents in the oceans and air flows in the atmosphere. The coast can also be considered a region, and will suffer severe impacts from sea level rise. Biogeochemical cycles See also: climate change feedback Climate change may have an effect on the carbon cycle in an interactive "feedback" process . A feedback exists where an initial process triggers changes in a second process that in turn influences the initial process. A positive feedback intensifies the original process, and a negative feedback reduces it (IPCC, 2007d:78).[11] Models suggest that the interaction of the climate system and the carbon cycle is one where the feedback effect is positive (Schneider et al.., 2007:792).[10] Using the A2 SRES emissions scenario, Schneider et al.. (2007:789) found that this effect led to additional warming by 2100, relative to the 1990-2000 period, of 0.1 to 1.5 °C. This estimate was made with high confidence. The climate projections made in the IPCC Forth Assessment Report of 1.1 to 6.4 °C account for this feedback effect. On the other hand, with medium confidence, Schneider et al.. (2007) commented that additional releases of GHGs were possible from permafrost, peat lands, wetlands, and large stores of marine hydrates at high latitudes. Glacier retreat and disappearance Main article: Retreat of glaciers since 1850 A map of the change in thickness of mountain glaciers since 1970. Thinning in orange and red, thickening in blue. IPCC (2007a:5) found that, on average, mountain glaciers and snow cover had decreased in both the northern and southern hemispheres.[3] This widespread decrease in glaciers and ice caps has contributed to observed sea level rise. With very high or high confidence, IPCC (2007d:11) made a number of predictions relating to future changes in glaciers:[11] * Mountainous areas in Europe will face glacier retreat * In Latin America, changes in precipitation patterns and the disappearance of glaciers will significantly affect water availability for human consumption, agriculture, and energy production * In Polar regions, there will be reductions in glacier extent and the thickness of glaciers. Oceans The role of the oceans in global warming is a complex one. The oceans serve as a sink for carbon dioxide, taking up much that would otherwise remain in the atmosphere, but increased levels of CO2 have led to ocean acidification. Furthermore, as the temperature of the oceans increases, they become less able to absorb excess CO2. Global warming is projected to have a number of effects on the oceans. Ongoing effects include rising sea levels due to thermal expansion and melting of glaciers and ice sheets, and warming of the ocean surface, leading to increased temperature stratification. Other possible effects include large-scale changes in ocean circulation. Acidification Main article: Ocean acidification Dissolving CO2 in seawater increases the hydrogen ion (H+) concentration in the ocean, and thus decreases ocean pH. Caldeira and Wickett (2003) placed the rate and magnitude of modern ocean acidification changes in the context of probable historical changes during the last 300 million years.[15] Since the industrial revolution began, it is estimated that surface ocean pH has dropped by slightly more than 0.1 units (on the logarithmic scale of pH; approximately a 30% increase in H+), and it is estimated that it will drop by a further 0.3 to 0.5 units (more than doubling ocean H+ concentrations) by 2100 as the oceans absorb more anthropogenic CO2.[15] [16][17] Oxygen depletion The amount of oxygen dissolved in the oceans may decline, with adverse consequences for ocean life.[18][19] Sea level rise Main article: Current sea level rise IPCC (2007a:5) reported that since 1961, global average sea level had risen at an average rate of 1.8 [1.3 to 2.3] mm/yr.[3] Between 1993 and 2003, the rate increased above the previous period to 3.1 [2.4 to 3.8] mm/yr. IPCC (2007a) were uncertain whether the increase in rate from 1993 to 2003 was due to natural variations in sea level over the time period, or whether it reflected an increase in the underlying long-term trend. IPCC (2007a:13, 14) projected sea level rise to the end of the 21st century using the SRES emission scenarios. Across the six SRES marker scenarios, sea level was projected to rise by 18 to 59 cm (7.1 to 23.2 inches). This projection was for the time period 2090-2099, with the increase in level relative to average sea levels over the 1980-1999 period. Due to a lack of scientific understanding, this sea level rise estimate does not include all of the possible contributions of ice sheets (see the section on abrupt or irreversible changes). Temperature rise From 1961 to 2003, the global ocean temperature has risen by 0.10 °C from the surface to a depth of 700 m. There is variability both year-to-year and over longer time scales, with global ocean heat content observations showing high rates of warming for 1991 to 2003, but some cooling from 2003 to 2007.[20] The temperature of the Antarctic Southern Ocean rose by 0.17 °C (0.31 °F) between the 1950s and the 1980s, nearly twice the rate for the world's oceans as a whole [21]. As well as having effects on ecosystems (e.g. by melting sea ice, affecting algae that grow on its underside), warming reduces the ocean's ability to absorb CO2.[citation needed] Social systems Main article: Climate change, industry and society Food supply Main article: Climate change and agriculture See also: Food security, Food vs fuel, and 2007–2008 world food price crisis Climate change will impact agriculture and food production around the world due to: the effects of elevated CO2 in the atmosphere, higher temperatures, altered precipitation and transpiration regimes, increased frequency of extreme events, and modified weed, pest, and pathogen pressure (Easterling et al.., 2007:282).[22] In general, low-latitude areas are at most risk of having decreased crop yields (Schneider et al.., 2007:790).[10] With low to medium confidence, Schneider et al.. (2007:787) concluded that for about a 1 to 3°C global mean temperature increase (by 2100, relative to the 1990-2000 average level) there would be productivity decreases for some cereals in low latitudes, and productivity increases in high latitudes. With medium confidence, global production potential was predicted to: * increase up to around 3°C, * very likely decrease above about 3 to 4°C. Most of the studies on global agriculture assessed by Schneider et al.. (2007:790) had not incorporated a number of critical factors, including changes in extreme events, or the spread of pests and diseases. Studies had also not considered the development of specific practices or technologies to aid adaptation. Health Human beings are exposed to climate change through changing weather patterns (temperature, precipitation, sea-level rise and more frequent extreme events) and indirectly through changes in water, air and food quality and changes in ecosystems, agriculture, industry and settlements and the economy (Confalonieri et al.., 2007:393).[23] According to a literature assessment by Confalonieri et al.. (2007:393), the effects of climate change to date have been small, but are projected to progressively increase in all countries and regions. With high confidence, Confalonieri et al.. (2007:393) concluded that climate change had altered the seasonal distribution of some allergenic pollen species. With medium confidence, they concluded that climate change had: * altered the distribution of some infectious disease vectors * increased heatwave-related deaths With high confidence, IPCC (2007d:48) projected that:[11] * the health status of millions of people would be affected through, for example, increases in malnutrition; increased deaths, diseases and injury due to extreme weather events; increased burden of diarrhoeal diseases; increased frequency of cardio-respiratory diseases due to high concentrations of ground-level ozone in urban areas related to climate change; and altered spatial distribution of some infectious diseases. * climate change would bring some benefits in temperate areas, such as fewer deaths from cold exposure, and some mixed effects such as changes in range and transmission potential of malaria in Africa. Overall, IPCC (2007d:48) expected that benefits would be outweighed by negative health effects of rising temperatures, especially in developing countries. With very high confidence, Confalonieri et al. (2007:393) concluded that economic development was an important component of possible adaptation to climate change. Economic growth on its own, however, was not judged to be sufficient to insulate the world's population from disease and injury due to climate change. The manner in which economic growth occurs was judged to be important, along with how the benefits of growth are distributed in society. Examples of other important factors in determining the health of populations were listed as: education, health care, and public-health infrastructure.

Thursday, January 13, 2011










The term public administration has been defined differently by different scholars since it is a field of inquiry with a diverse scope. For instance, Woodrow Wilson defined public administration as, a systematic and efficient execution of public law. This definition implies that public administration is concerned by public law in public organization. Therefore, public administration is the implementation of government policy and an academic discipline that studies this implementation and that prepares civil servants for this work, with the fundamental goal to advance management and policies so that government can function well.
On the other hand, Private administration refers to the individuals and processes that carry out the manufacturing, marketing, retailing, and providing of goods and services in exchange for payment.
The essence of this paper is to compare and contrast public administration versus private administration, as well as their similarities and differences.
 Public administration encompasses the individuals and processes that carry out laws, rules, and regulations that are issued by legislatures or other elected officials. While Private administration refers to the individuals and processes that carry out the manufacturing, marketing, retailing, and providing of goods and services in exchange for payment.
 In public administration, the decision must be and should be pluralistic. That’s means all key decisions are made in a politicized environment whereby there is maximum participation. A decision making hierarchy where consensus must be achieved at each level, ideally, an informed decision. While private administration's decision-making is much simpler- it's monopolistic or close to monopolistic. Thus a goal is clearly defined since decision-making would avoid any conflicts in interest.
 Private organizations are driven by profit motive while Public organizations are defined by public interest. Private administration has an ultimate mission in pursuit of profit or stability or growth of revenues while public administration mission is to enact public policies which are ambiguous and vague, but the enactment of these policies make public administration's purpose to be more ambiguous.
 Public administration is meant to provide public services and goods if the public requires it, while private administration is established for providing consumer’s goods and services as long as consumer can afford it.
 Information in public administration is subject to full or partial disclosure, depending on the nature of information and government agency, unless if the data involves national security. While information in private administration is not accessible to the public. Government agencies may only require private administrations to report certain data, such as earnings, employee demographics, time records, among other related data required by certain government agencies.
 Public administration must operate in public eye. Public administrator’s actions are constantly subjected to public scrutiny, carrying out public policy and also responding to public demands. While an administrator in a private administration may work in relative obscurity.
 Public officials tend to have no special motivations but rather maximize work for self-interest as power, prestige and income or considerations of the public interest.
Political aspect is apparent in both public and private .Policy decisions normally affect the companies directly or indirectly, through laws and regulations and financial support.

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