Introduction
The aim of this report is to evaluate to what extent anthropogenic greenhouse gas emissions are responsible for recent global climate change (Karl and Trenberth, (2003), and to identify the main uncertainties associated with future climate modelling. These queries are firstly explored by analyzing the effects that natural causes such as solar volcanic eruptions and solar output have had on recent global climate. This is then contrasted by looking at the volumes of greenhouse gases that are anthropogenically emitted and the observed effects of this. Finally, uncertainties over future emissions and climate modelling are discussed, along with its associated implications.
3. Materials and methods
Anthropogenic climate change is the belief that greenhouse gases (CO2, NO2 and CH4) emitted by human activity are to blame for the rapid increase in global temperature seen since the industrial revolution (Fig. 1).
Anthropogenic climate occurs through the enhanced greenhouse effect. This is where solar radiation travels through the surface, which then absorbs and reflects
atmosphere to the earth’s surface, which absorbs and reflects this energy back at IR wavelength (700nm-1mm).
About 70% of solar energy is absorbed by the Earth’s surface and lower atmosphere, with the rest being reflected back to space through clouds and albedo (NASA, 2013).
The absorbed radiation warms the planet (Fig. 2) by being re-radiated into the atmosphere, where some of it gets absorbed by greenhouse gases like water vapour and carbon dioxide. These gases then radiate that heat back towards Earth, heating the lower atmosphere and surface, thus enhancing the heating they get from direct sunlight (NASA, 2013).
So we must look as to what ext...
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...egy is put into action, a doubling of CO2 in the atmosphere will result in a 1.5-4.5C increase in global surface temperatures
4. Results and Interpretation
The range of IPCC global surface temperature predictions are quite large from year to year. This is partly to do the uncertainty of future emissions, but also, probably most importantly, due to uncertainties in climate modelling.
This is because while the effect of increased greenhouse gas emission on the climate is well understood, the effects of several positive feedback loops as a result of this, aren’t, so they’re not properly accounted for in the models.
5. Conclusion
So, to summarise:
Anthropogenic climate change happens due to enhanced greenhouse effect and deforestation of carbon sinks.
Recent climate change is partly due to volcanic eruptions and changes in solar output, but an
One of the main causes of the increase in Earth’s temperature is greenhouse gases. Greenhouse gases are gases that are trapped in the atmosphere. The gases consist of carbon dioxide, nitrous oxide, and methane. They trapped heat from the sun from returning back into the atmosphere. Over the last 100 hundred years we have increased the earth’s average temperature by 1.4 degree fahrenheit (Carey). This is mainly due to the fact we are producing ten times more greenhouse gas than before. It is exp...
In the statistical distribution of weather condition and its perfect pattern in an amount of time ranging from decades to centuries to millions of years, a substantial, long-lasting and drastic change is largely known as Climate change. It may be a change in more or fewer extreme weather events or in the distribution of weather more or less the average conditions or in average weather conditions. With the usage of theoretical models and observations methods, scientists, experts and specialists in this particular field actively works in order to perfectly understand past and future climate under certain situation and circumstances.
Throughout history climates have drastically changed. There have been shifts from warm climates to the Ice Ages (Cunningham & Cunningham, 2009, p.204). Evidence suggests there have been at least a dozen abrupt climate changes throughout the history of the earth. There are a few suspected reasons for these past climate changes. One reason may be that asteroids hitting the earth and volcanic eruptions caused some of them. A further assumption is that 22-year solar magnetic cycles and 11-year sunspot cycles played a part in the changes. A further possibility is that a regular shifting in the angle of the moon orbiting earth causing changing tides and atmospheric circulation affects the global climate (Cunningham & Cunningham, 2009, p.205). Scientific studies suggest that all these played a role in past global warming and cooling periods. Today, however, there is a lot of conflict on whether humans are causing a global warming that could be disastrous to humans and all species of plants and animals on this earth. This paper will first explain the greenhouse effect, then take a look at both sides argument, and, finally, analyze the effect of global warming on world-wide sustainability
There is no longer any question that our world climate has changed (King, 2004). Over the last 100 years, "temperatures have risen by about 0.6 degrees Celsius and global sea level has risen by about 20cm" (K...
“Climate change: How do we know?” NASA. NASA n. d. n. pag. Web. 28 November
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In talking about global warming, we need to learn what causes the greenhouse effect. Rays from the sun are taken up and absorbed by water vapor that is natural in the atmosphere. The United States emits the largest man made greenhouse gases in the world. As Americans we must realize the responsibility to reduce the emissions. (Gore, Albert) Water Vapor is eighty percent of greenhouse warming. The last twenty percent results from other gases that are in very little amounts. A huge absorber of the sun’s heat rays is carbon dioxide. Us as humans release a lot of carbon dioxide. When fossil fuels are burned, they release big amounts of carbon dioxide. Carbon dioxide is on the increase in our atmosphere due to car emissions. Approximately eighty percent of CO2 increases because of man’s use of fossil fuels. When there is more carbon dioxide in our atmosphere the more sun rays are absorbed. In result to this happening this will cause the earth and the earths atmosphere to warm. When the earth is warming, water temperatures will start to get warmer. Oceans and lakes will get warmer in result f...
The commonly debated “greenhouse effect” refers to “the global-average temperature increase that has been observed over the last one hundred years or more” (Spencer). President Barack Obama addressed the issue as an effort to highlight its severity, "We have to all shoulder the responsibility for keeping the planet habitable, or we’re going to suffer the consequences – together” (Leader). The earth’s increasing atmospheric and oceanic temperatures result in climate changes due to cumulative amounts of carbon dioxide (CO2) in the atmosphere.
Water vapor increases as the Earth's atmosphere warms, but so does the possibility of clouds and precipitation, making these some of the most important feedback mechanisms to the greenhouse
Schmidt, G. A., R. A. Ruedy, R. L. Miller, & A. A. Lacis (2010), Attribution of the present‐day total greenhouse effect, Journal of Geophysical Research, 115, D20106, doi:10.1029/2010JD014287.
atmosphere. If there is more carbon dioxide in the atmosphere more rays from the sun are
...e sun, this is of a longer wavelength and is absorbed by the atmosphere. The Earths atmosphere, thus acts like the glass of a green house, hence the 'greenhouse effect'.
The earth is a complex system, which continues to evolve and change. Climate change and global warming are currently popular in the political agenda. But what does “climate” really mean? The difference between weather and climate can be conveyed in a single sentence: “Climate is what you expect; weather is what you get.” Based on research of the geologic record, we know that climate change has happened throughout Earth's history and at present, ever-increasing evidence points to the roles that humans play in altering Earth systems. The Earth and its atmosphere receive heat energy from the sun; the atmospheric heat budget of the Earth depends on the balance between incoming solar radiation and outgoing radiation from the planet; which has been constant over the last few thousand years. However present evidence seems to suggest that the recent increase in temperature has been brought about by pollution of the atmosphere, in particular the release of huge amounts of carbon dioxide, mostly through Anthropogenic Forcing (human activity) and other various internal and external factors. I...
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