CHAPTER I- PREFACE
Nowadays, climate change is one of the hottest issues that discussed by all countries in the earth. UN conference that held in
The damage of Indonesia forestry which caused by illegal logging, forest burning and opening new palm land has affected for reducing of world environment, so the environmental problem in Indonesia become an international problem because the effect not only faced in Indonesia but also in another countries. Many kind of step have done to decrease the damage of forestry that cause one of the factor increasing of global warming and climate change besides using of glasshouse. One of the step that prevent increasing of climate change and global warming is reboisation. Reboisation become one of the way t avoid global warming and climate change .besides force from another industry countries for decreasing usage of chemical gas which cause high rate of global warming.
Therefore, this issues become current to talk or discuss because it related to the safety of the world.
Global warming refers to the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation.
The global average air temperature near the Earth's surface rose 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the last 100 years. The Intergovernmental Panel on Climate Change (IPCC) concludes, "most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations" via the greenhouse effect. Natural phenomena such as solar variation combined with volcanoes probably had a small warming effect from pre-industrial times to 1950 and a small cooling effect from 1950 onward. These basic conclusions have been endorsed by at least 30 scientific societies and academies of science, including all of the national academies of science of the major industrialized countries. While individual scientists have voiced disagreement with some of the main conclusions of the IPCC, the overwhelming majority of scientists working on climate change are in agreement with them.
Climate model projections summarized by the IPCC indicate that average global surface temperature will likely rise a further 1.1 to 6.4 °C (2.0 to 11.5 °F) during the 21st century. The range of values results from the use of differing scenarios of future greenhouse gas emissions as well as models with differing climate sensitivity. Although most studies focus on the period up to 2100, warming and sea level rise are expected to continue for more than a millennium even if greenhouse gas levels are stabilized. The delay in reaching equilibrium is a result of the large heat capacity of the oceans.
Increasing global temperatures will cause sea level to rise, and is expected to increase the intensity of extreme weather events and to change the amount and pattern of precipitation. Other effects of global warming include changes in agricultural yields, glacier retreat, species extinctions, and increases in the ranges of disease vectors.
Remaining scientific uncertainties include the amount of warming expected in the future, and how warming and related changes will vary from region to region around the globe. There is ongoing political and public debate worldwide regarding what, if any, action should be taken to reduce or reverse future warming or to adapt to its expected consequences. Most national governments have signed and ratified the Kyoto Protocol, aimed at reducing greenhouse gas emissions.
The term "global warming" is a specific example of the broader term climate change, which can also refer to global cooling. In common usage, the term refers to recent warming and implies a human influence. The United Nations Framework Convention on Climate Change (UNFCCC) uses the term "climate change" for human-caused change, and "climate variability" for other changes. The term "anthropogenic global warming" is sometimes used when focusing on human-induced changes.
Carbon dioxide during the last 400,000 years and (inset above) the rapid rise since the Industrial Revolution; changes in the Earth's orbit around the Sun, known as Milankovitch cycles, are believed to be the pacemaker of the 100,000 year ice age cycle.Recent increases in atmospheric carbon dioxide (CO2). The monthly CO2 measurements display small seasonal oscillations in an overall yearly uptrend; each year's maximum is reached during the Northern Hemisphere's late spring, and declines during the Northern Hemisphere growing season as plants remove some CO2 from the atmosphere.The Earth's climate changes in response to external forcing, including variations in its orbit around the sun (orbital forcing), volcanic eruptions, and atmospheric greenhouse gas concentrations. The detailed causes of the recent warming remain an active field of research, but the scientific consensus identifies elevated levels of greenhouse gases due to human activity as the main influence. This attribution is clearest for the most recent 50 years, for which the most detailed data are available. In contrast to the scientific consensus that recent warming is mainly attributable to elevated levels of greenhouse gases, other hypotheses have been suggested to explain the observed increase in mean global temperature. One such hypothesis proposes that warming may be the result of variations in solar activity.
None of the effects of forcing are instantaneous. The thermal inertia of the Earth's oceans and slow responses of other indirect effects mean that the Earth's current climate is not in equilibrium with the forcing imposed. Climate commitment studies indicate that even if greenhouse gases were stabilized at 2000 levels, a further warming of about 0.5 °C (0.9 °F) would still occur.
· Temperature changes
Two millennia of mean surface temperatures according to different reconstructions, each smoothed on a decadal scale. The unsmoothed, annual value for 2004 is also plotted for reference.
Global temperatures on both land and sea have increased by 0.75 °C (1.35 °F) relative to the period 1860–1900, according to the instrumental temperature record. This measured temperature increase is not significantly affected by the urban heat island effect. Since 1979, land temperatures have increased about twice as fast as ocean temperatures (0.25 °C per decade against 0.13 °C per decade). Temperatures in the lower troposphere have increased between 0.12 and 0.22 °C (0.22 and 0.4 °F) per decade since 1979, according to satellite temperature measurements. Temperature is believed to have been relatively stable over the one or two thousand years before 1850, with possibly regional fluctuations such as the Medieval Warm Period or the Little Ice Age.
Sea temperatures increase more slowly than those on land both because of the larger effective heat capacity of the oceans and because the ocean can lose heat by evaporation more readily than the land. Since the Northern Hemisphere has more land mass than the Southern Hemisphere it warms faster; also there are extensive areas of seasonal snow cover subject to the snow-albedo feedback. Although more greenhouse gases are emitted in the Northern than Southern Hemisphere this does not contribute to the asymmetry of warming as the major gases are essentially well-mixed between hemispheres.
Based on estimates by NASA's Goddard Institute for Space Studies, 2005 was the warmest year since reliable, widespread instrumental measurements became available in the late 1800s, exceeding the previous record set in 1998 by a few hundredths of a degree. Estimates prepared by the World Meteorological Organization and the Climatic Research Unit concluded that 2005 was the second warmest year, behind 1998.
Anthropogenic emissions of other pollutants—notably sulfate aerosols—can exert a cooling effect by increasing the reflection of incoming sunlight. This partially accounts for the cooling seen in the temperature record in the middle of the twentieth century, though the cooling may also be due in part to natural variability. James Hansen and colleagues have proposed that the effects of the products of fossil fuel combustion -- CO2 and aerosols -- have largely offset one another, so that warming in recent decades has been driven mainly by non-CO2 greenhouse gases.
Paleoclimatologist William Ruddiman has argued that human influence on the global climate began around 8,000 years ago with the start of forest clearing to provide land for agriculture and 5,000 years ago with the start of Asian rice irrigation. Ruddiman's interpretation of the historical record, with respect to the methane data, has been disputed.
The study has been conducted through the inventory and characterization of past and ongoing rehabilitation initiatives and their changing profile in each of the selected regions by conducting series of consultations and workshops with national and local stakeholders. This is in conjunction with in depth evaluation and comparative analyses of all factors, within and across projects, and based on the literature reviews of project-related documents or other secondary sources. The main output of the study is Country Syntheses on Lessons Learned from the nature of rehabilitation efforts in each country drawn from subsidiary outputs of Database I of rehabilitation initiatives and their key features, and Database II of detailed assessment of selected rehabilitation case studies.
The focus of review would be initiatives that aim to actually establish trees on formerly forested land; and not strictly technical trials of species or planting design. Integrated projects with forest rehabilitation components will also be included in this review. The “Forest Rehabilitation Initiatives” included in the study framed by the description: Deliberate activities1 aimed at artificial and/or natural regeneration of trees2 on formerly forested grasslands, brushlands, scrublands, or barren areas3 for the purpose of enhancing productivity, livelihood, and/or environmental service benefits4.
Further explanation:
1Deliberate activities could include technical interventions, new or revised socio-economic arrangements, and new or revised institutional arrangements (land tenure, policies, rules and regulations, monitoring).
2Artificial and/or natural regeneration of trees - any rehabilitation methods that involve trees – from agroforestry to plantations to assisted natural regeneration.
3Formerly forested grasslands, brushlands, scrublands, or barren areas – initiatives that aim to put trees back on formerly forested lands, and not include the rehabilitation of degraded or secondary forest areas (reclamation on mined areas will also be excluded). Type of environments is restricted to upland and lowland areas, and excluding wetlands.
4Purpose of enhancing productivity, livelihood, and/or environmental service benefits – Objectives could span the whole range from productivity to livelihood and/or environmental benefits for different stakeholders.
The Ministry of Forestry in
Global warming and climate change are caused by damaged forest and also the increasing of glasshouse gas in industry countries. This condition has made temperature high. So the melting of polar ices that increase sea water level from the continent. This phenomenon gives great effect to the safety of the earth. All countries have to participate in this extreme climate change.
Responsibility for climate change and global warming is the world’s problem. Where each industry countries can not say that develop countries are responsible for this problem.
Therefore, reboisation and global warming have to be the first attention and high commitment to implement the real one in reducing the rate of global warming.
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LITERATURE
1. Summary for Policymakers (PDF). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change (2007-02-05). Retrieved on 2007-02-02.
2. Hegerl, Gabriele C.; et al. (2007-05-07). Understanding and Attributing Climate Change (PDF). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change 690. Intergovernmental Panel on Climate Change.
3. //http.www.kompas.com
4. //http.www.wikipedia.com
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