Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent global warming and related climate changes on Earth. The effort has focused on changes observed during the period of instrumental temperature record, particularly in the last 50 blogger.com is the period when human activity has grown fastest and observations of the atmosphere above Oct 22, · Global Warming Essay 3 ( words) Global warming is the steady and continuous rise in the level of earth temperature. Out earth surface is becoming hotter day by day just because of some unnoticeable habits of human beings all across the world Jun 24, · Global warming is a rise in the surface temperature of the earth that has changed various life forms on the earth. The issues that cause global warming are divided into two categories include “natural” and “human influences” of global warming. Natural Causes of Global Warming. The climate has continuously changing for centuries
Essay on Global Warming for Children and Students
Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent global warming and related climate changes on Earth. This is the period when human activity has grown fastest and observations of the atmosphere above the surface have become available. According to the Intergovernmental Panel on Climate Change IPCCit is "extremely likely" [5] that human influence was the dominant cause of global warming between and Some of the main human activities that contribute to global warming are: [8].
In addition to human activities, some natural mechanisms can also cause climate change, including for example, climate oscillationschanges in solar activityand volcanic activity. Multiple lines of evidence support attribution of recent global warming causes and effects essay change to human activities: [9].
The IPCC's attribution of recent global warming to human activities reflects the view of the scientific community, global warming causes and effects essay, [10] [11] [12] and is also supported by other scientific organizations worldwide. Factors affecting Earth's climate can be broken down into feedbacks and forcings.
External forcings include natural phenomena such as volcanic eruptions and variations in the sun's output. Radiative forcing is a measure of how various factors alter the energy balance of the Earth's atmosphere. Between the start of the Industrial Revolution inand the yearthe increase in the atmospheric concentration of carbon dioxide chemical formula : CO 2 led to a positive radiative forcing, averaged over the Earth's surface areaof about 1.
Climate feedbacks can either amplify or dampen the response of the climate to a given forcing. The climate system will vary in response to changes in forcings. This internal variability is a result of complex interactions between components of the climate system, such as the coupling between the atmosphere and ocean see also the later section on Internal climate variability and global warming. Detection and attribution of climate signals, as well as its common-sense meaning, has a more precise definition within the climate change literature, as expressed by the IPCC.
CO 2 is absorbed and emitted naturally as part of the carbon cyclethrough animal and plant respirationvolcanic eruptionsand ocean-atmosphere exchange, global warming causes and effects essay. The high-accuracy measurements of atmospheric CO 2 concentration, initiated by Charles David Keeling inconstitute the master time series documenting the changing composition of the atmosphere, global warming causes and effects essay.
In Maythe concentration of CO 2 in the atmosphere reached ppm. The last time when it reached this level was 2. Without human intervention, it would be ppm. Along with CO 2methane and to a lesser extent nitrous oxide are also major forcing contributors to the greenhouse effect.
The Kyoto Protocol lists these together with hydrofluorocarbon HFCsperfluorocarbons PFCsand sulfur hexafluoride SF 6[28] which are entirely artificial gases, as contributors to radiative forcing. The chart at right attributes anthropogenic greenhouse gas emissions to eight main economic sectors, of which the largest contributors are power stations many of which burn coal or other fossil fuelsindustrial processes, transportation fuels generally fossil fuelsand agricultural by-products mainly methane from enteric fermentation and nitrous oxide from fertilizer use.
Water vapor is the most abundant greenhouse gas and is the largest contributor to the natural greenhouse effect, despite having a short atmospheric lifetime [23] about 10 days. However, on a global scale, global warming causes and effects essay, the concentration of water vapor is controlled by temperature, which influences overall rates of evaporation and precipitation.
Global warming causes and effects essay change is attributed to land use for two main reasons. Between andabout two-thirds of anthropogenic CO 2 emissions were produced from burning fossil fuels, and about one-third of emissions from changes in land use, [31] primarily deforestation. Some of the causes of climate change are, generally, not connected with it directly in the media coverage.
For example, the harm done by humans to the populations of Elephants and Monkeys contributes to deforestation therefore to climate change. A second reason that climate change has been attributed to land use is that the terrestrial albedo is often altered by use, which leads to radiative forcing.
This effect is more significant locally than globally. With virtual certainty, scientific consensus has attributed various forms of climate change, chiefly cooling effects, to aerosolswhich are small particles or droplets suspended in the atmosphere.
Over the past years human activities have released increasing quantities of greenhouse gases into the atmosphere.
This has led to increases in mean global temperature, or global warming. Other human effects are relevant—for example, sulphate aerosols are believed to have a cooling effect. Natural factors also contribute. According to the historical temperature record of the last century, the Earth's near-surface air temperature has risen around 0.
A historically important question in climate change research has regarded the relative importance of human activity and non- anthropogenic causes during the period of instrumental record. In the Second Assessment Report SARthe IPCC made the widely quoted statement that "The balance of evidence suggests a discernible human influence on global climate".
The phrase "balance of evidence" suggested the English common-law standard of proof required in civil as opposed to criminal courts: not as high as "beyond reasonable doubt". In the Third Assessment Report TAR refined this, saying "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities". Over the past five decades there has been a global warming of approximately 0. Among the possible factors that could produce changes in global mean temperature are internal variability of the climate system, external forcing, an increase in concentration of greenhouse gases, or any combination of these.
Current studies indicate that the increase in greenhouse gases, most notably CO 2global warming causes and effects essay, is mostly responsible for the observed warming. Evidence for this conclusion includes:. Recent scientific assessments find that most of the warming of the Earth's surface over the past 50 years has been caused by human activities see also the section on scientific literature and opinion.
This conclusion rests on multiple lines of evidence. Like global warming causes and effects essay warming "signal" that has gradually emerged from the "noise" of natural climate variability, the scientific evidence for a human influence on global climate has accumulated over the past several decades, from many hundreds of studies.
No single study is a " smoking gun. The first line of evidence is based on a physical understanding of how greenhouse gases trap heat, how the climate system responds to increases in greenhouse gases, and how other human and natural factors influence climate. The second line of evidence is from indirect estimates of climate changes over the last 1, to 2, global warming causes and effects essay, years.
These records are obtained from living things and their remains like tree rings and corals and from physical quantities like the ratio between lighter and heavier isotopes of oxygen in global warming causes and effects essay coreswhich change in measurable ways as climate changes.
The lesson from these data is that global surface temperatures over the last several decades are clearly unusual, in that they were higher than at any time during at least the past years. For the Northern Hemispherethe recent temperature rise is clearly unusual in at least the last 1, years see graph opposite.
The third line of evidence is based on the broad, qualitative consistency between observed changes in climate and the computer model simulations of how climate would be expected to change in response to human activities. For example, when climate models are run with historical increases in greenhouse gases, they show gradual warming of the Earth and ocean surface, increases in ocean heat content and the temperature of the lower atmosphere, a rise in global sea level, retreat of sea ice and snow cover, cooling of the stratospherean increase in the amount of atmospheric water vapor, and changes in large-scale precipitation and pressure patterns.
These and other aspects of modelled climate change are in agreement with observations. Finally, there is extensive statistical evidence from so-called "fingerprint" studies. Each factor that affects climate produces a unique pattern of climate response, much as each person has a unique fingerprint. Fingerprint studies exploit these unique signatures, and allow detailed comparisons of modelled and observed climate change patterns.
Global warming causes and effects essay rely on such studies to attribute observed changes in climate to a particular cause or set of global warming causes and effects essay. In the real world, the climate changes that have occurred since the start of the Industrial Revolution are due to a complex mixture of human and natural causes.
The importance of each individual influence in this mixture changes over time. Of course, there are not multiple Earths, which global warming causes and effects essay allow an experimenter to change one factor at a time on each Earth, thus helping to isolate different fingerprints.
Therefore, climate models are used to study how individual factors affect climate. For example, a single factor like greenhouse gases or a set of factors can be varied, and the response of the modelled climate system to these individual or combined changes can thus be studied. These projections have been confirmed by observations shown above. When human influences are removed from the model experiments, results suggest that the surface of the Earth would actually have cooled slightly over the last 50 years.
The clear message from fingerprint studies is that the observed warming over the last half-century cannot be explained by natural factors, and is instead caused primarily by human factors. Another fingerprint of human effects on climate has been identified by looking at a slice through the layers of the atmosphere, global warming causes and effects essay, and studying the pattern of temperature changes from the surface up through the stratosphere see the section on solar activity.
The earliest fingerprint work focused on changes in surface and atmospheric temperature. Scientists then applied fingerprint methods to a whole range of climate variables, identifying human-caused climate signals in the heat content of the oceans, the height of the tropopause the boundary between the troposphere and stratospherewhich has shifted upward by hundreds of feet in recent decadesthe geographical patterns of precipitation, drought, surface pressure, and the runoff from major river basins.
Studies published after the appearance of the IPCC Fourth Assessment Report in have also found human fingerprints in the increased levels of atmospheric moisture both close to the surface and over the full extent of the atmospherein the decline of Arctic sea ice extent, and in the patterns of changes in Arctic and Antarctic surface temperatures. The message from this entire body of work is that the climate system is telling a consistent story of increasingly dominant human influence — the changes in temperature, ice extent, moisture, and circulation patterns fit together in a physically consistent way, like pieces in a complex puzzle.
Increasingly, this type of fingerprint work is shifting its emphasis. As noted, clear and compelling scientific evidence supports the case for a pronounced human influence on global climate. Much of the recent attention is now on climate changes at continental and regional scales, and on variables that can have large impacts on societies. For example, scientists have established causal links between human activities and the changes in global warming causes and effects essaymaximum and minimum diurnal temperature, and the seasonal timing of runoff over mountainous regions of the western United States.
Human activity is likely to have made a substantial contribution to ocean surface temperature changes in hurricane formation regions. Researchers are also looking beyond the physical climate system, and are beginning to tie changes in the distribution and seasonal behaviour of plant and animal species to human-caused changes in temperature and precipitation. For over a decade, one aspect of the climate change story seemed to show a significant difference between models and observations.
In the tropics, all models predicted that with a rise in greenhouse gases, the troposphere would be expected to warm more rapidly than the surface. Observations from weather balloons, satellites, and surface thermometers seemed to show the opposite behaviour more rapid warming of the surface than the troposphere. This issue was a stumbling block in understanding the causes of climate change. It is now largely resolved, global warming causes and effects essay.
Research showed that there were large uncertainties in the satellite and weather balloon data. When uncertainties in models and observations are properly accounted for, newer observational data sets with better treatment of known problems are in agreement with climate model results.
This does not mean, however, that all remaining differences between models and observations have been resolved. The observed changes in some climate variables, such as Arctic sea ice, some aspects of precipitation, and patterns of surface pressure, appear to be proceeding much more rapidly than models have projected. The reasons for these differences are not well understood. Nevertheless, the bottom-line conclusion from climate fingerprinting is that most of the observed changes studied to date are consistent with each other, and are also consistent with our scientific understanding of how the climate system would be expected to respond to the increase in heat-trapping gases resulting from human activities.
One of the subjects discussed in the literature is whether or not extreme weather events can be attributed to human activities. Seneviratne et al. They were, however, more confident over attributing changes in long-term trends of extreme weather. For example, Seneviratne et al. Another way of viewing the problem is to consider the effects of human-induced climate change on the probability of future extreme weather events. Stott et al.
Their conclusion was that human activities had very likely more than doubled the risk of heat waves of this magnitude. An analogy can be made between an athlete on steroids and human-induced climate change.
Global Warming Essay In English (500 Words) - Causes and Effects of Global Warming essay 500 words
, time: 15:28Global Warming - Definition, Facts, Causes and Effects of Global Warming | NRDC
3. Global Warming Essay: Causes, Effects & Solutions Introduction. Global warming is a phenomenon due to which the temperature of the earth’s surface; land, water, and atmosphere, is rising year-by-year due to many natural and human-made causes. Causes of Global Warming Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent global warming and related climate changes on Earth. The effort has focused on changes observed during the period of instrumental temperature record, particularly in the last 50 blogger.com is the period when human activity has grown fastest and observations of the atmosphere above Apr 07, · Global warming causes, effects, extreme weather, facts, and relation to climate change. Everything you wanted to know about our changing climate but were too afraid to ask
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