What role does human activity play in the current global warming trend?Muhammed Sadik Panakkattil

The term "global warming" refers to the increase in the average temperature of global surface air and oceans since about 1950, and to continuing increases in those temperatures. Global warming is primarily a problem of too much carbon dioxide (CO2) in the atmospherewhich acts as a blanket, trapping heat and warming the planet. The causes of global warming are split up into two groups, man-made and natural causes. As people burn fossil fuels such as coal, oil and natural gas for energy or cut down and burn forests to create pastures and plantations, carbon accumulates and overloads our atmosphere. One of the natural causes is the volcanic eruption; large volcanic eruptions have resulted in significant increase in temperature as volcano's release carbon dioxide and therefore double the amount of greenhouse gases. Heat absorbing gases are known as greenhouse gases. The warming of the atmosphere is called the greenhouse effect. There have been many discussions about whether the human activity plays the biggest part in global warming or the worlds biological system is adjusting its nature as the earth goes through a cycle of climate change. However this essay mainly argues that human activity is the major contributor to climate change and therefore global warming.

According to the topic the first perspective is that humans are responsible for the rapid changes in the global world while not considering the causes of natural cycles. The Guardian published an article recently stating, New research reinforces human-caused global warming and a climate that's highly sensitive to an increased greenhouse effect. The Guardian summarises that humans are the significant cause of the current global warming and it will continue to grow because of the fact that doubling the amount of carbon dioxide in the atmosphere should affect the global surface by warming it by 1C. When fuels are burned it creates aerosols and greenhouse gases, the aerosols force the system in the cooling direction because the airborne particles scatter and absorb incoming sunlight and therefore this increases the quantity of greenhouse gases resulting in the planet warming. However the article fails to bring a trustworthy evidence to prove that how long this has been happening for and which parts of the world are more affected by it.However much more importantly, Guardian points out that energy reaching the planet is relatively stable, it's only increased by about 0.1 percent over the past 300 years. This implies that heat energy released from the sun is balanced and therefore extra warming is caused by human activity which makes the amount of energy reaching the planet unstable. This is a credible argument because it uses statistics to support the view. Another observation that the Guardian presents is that clouds will play in the sensitivity of the global climate to the increased greenhouse effect. This suggests that cloud responses to global warming have remained an important factor because the clouds cause both warming by increasing the greenhouse effect, and cooling by reflecting sunlight away from the Earth's surface. But this view can be criticised as a biased one because it has been researched by scientists called Steven Sherwood and Sandrine Bony, who may only expressed their opinions about global warming rather than compare with natural changes of the planet.

Likewise National Wildlife Federation (NWF) published an article titled Global Warming is Human Caused which concludes that the larger quantities of CO2 in the atmosphere are affecting global warming heavily and human activity has a significant impact on the increase in global. NWF states that the atmosphere naturally keeps our planet warm enough to survive. They argued that human activities, mainly burning fossil fuels cause more greenhouse gases to build up in the atmosphere. When there is a significant rise in the percentage of carbon dioxide in the air, the amount of heat captured by the carbon dioxide gas also increases. This in turn leads to an overall rise in the surface temperature of the earth. However the problem is that NWF failed to provide evidence which shows the level by which it increased over a period of time which may prove their argument to be reliable. The WNF then adds a point into the matter which asserts that for hundreds of thousands of years, changes in temperature have closely tracked with atmospheric CO2 concentrations which has been demonstrated by scientist Svante Arrhenius 100 years ago. The WNF is a reliable non-profit-organisation that clearly reveals that a big percentage of increase in global warming is caused by humans; however the durability of Svante Arrhenius research is not applicable to the current situation of global warming as there are many industrial economies which have emerged recently and the need for fossil energy is higher, therefore this view is not valid and does not represent the current global warming trend.Muhammed Sadik Panakkattil

The Skepticalscience posted an article (2013) highlight Empirical evidence that humans are causing global warming, which concludes that energy being trapped in the atmosphere corresponds exactly to the wavelengths of energy captured by CO2 and man-made carbon dioxide is causing the Earth to warm up significantly. They claim that the atmosphere plays a big role in the Earths warming and cooling system. This is supported when they say The laws of physics tell us that without theatmosphere, the Earth would be approximately 33C (59.4F) cooler than it actually is The greenhouse gases (carbon dioxide (CO2), methane (CH4), water vapour) trap the energy which comes from the sun and transmit to different premises. However when the quantity of greenhouse in the atmosphere reaches high and if an upward trend continues then it affects the climate change and can lead to many consequences such as global cooling and global warming. The Skeptical scientists calculations reveal that before the industrial revolution the amount of CO2 in the atmosphere was 280 parts per million and this was a balanced one. But then again the beginning of the industrial revolution (in the 18th century) has made a huge difference to the CO2 in the atmosphere and it went up to 400 parts per million. The use of factories and mass production has led to a depletion of certain natural resources, leaving the environment permanently damaged and it has the greatest impact on CO2 emissions are into the atmosphere. This is a credible source because the Skeptical Science explains what peer reviewed science has to say about global warming and making awareness that it has many consequences to the Earth.

The second possible reason for global warming is natural causes. Many experts and scientists claim that temperatures are neither the warmest nor are they producing the most extreme conditions. They found that world had a medieval warm period between the ninth and fourteenth centuries, with world temperatures higher than today's. The BBC published an article titled What happened to global warming? (October 2009) legitimately summarises that the earth's climate is dynamic and always changing through a natural cycle, and has done so on many occasions in the past. They also said that even if man is warming the planet, it is a small measure compared with natural causes; this is clear because there are many prominent natural factors responsible for global warming such as continental drift, volcanoes, ocean currents, the earth's tilt, and comets and meteorites. The BBC influences a scientist Piers Corbyn from Weatheraction who claims that solar charged particles impact us far more than is currently accepted, by looking at the recent solar activity and how it contributes to global warming, Piers Corbyns claim is naturally acceptable because the solar activity varies slightly on an approximately 11 year cycle due to the cyclical nature of sunspot activity. When the sunspot number is high there is an increase in solar irradiation which affects the total warming of the earth. However Piers Corbyn didnt provide any evidence to prove that how solar activity had impacted the earth previously and how serious this phenomenal is now.In addition the BBC states that in the last few years the Pacific Ocean has been losing its warmth and has recently started to cool down. Their estimate says that ocean cycles have a higher contribution to global warming. The oceans have a cycle in which warm and cool cycles repeat. These cycles reveal that earth is currently in a period in which a natural rise in global temperatures combined with warming from the greenhouse effect will push the planet through an era of rapid global warming. Also the BBC adds an extra point in which the professor Mojib Latif from IPCC (Intergovernmental Panel on Climate Change) says that we may indeed be in a period of cooling worldwide temperatures that could last another 10-20 years, this means that cooling can be as constant for couple of years but he is not completely sure that if it could happen for a world like now. Professor Latif is based at the Leibniz Institute of Marine Sciences at Kiel University in Germany and is one the world's top climate modellers. Therefore we can assume that his view is reliable.

Similarly the Telegraph published a news article titled (May 2013) Tim Yeo: humans may not be to blame for global warming, which concludes that scientific evidence shows there are natural causes which affect global warming massively, however man- made causes contributing to greenhouse gas concentrations have a strong or probability than natural causes. The Telegraph reports that Tim Yeo, the MP who oversees government policy on climate change says that the climate is changing is now overwhelming, the causes are not absolutely clear. There could be natural causes, natural phases that are taking place he reveals that the current warming trend is of particular significance because most of it is very likely human-induced and most of these climate changes are attributed to very small variations in Earths orbit that change the amount of heat energy our planet receives, Time Yeos assumption is powerful as he was one of the first senior figures to urge the party to take the issue of environmental change seriously. Therefore we could say that there are natural variations in Earth which may play a significant part in the total warming of the planet.Muhammed Sadik Panakkattil

To conclude, I believe that the recent global warming is not the result of natural causes but is, instead, the result of human activity. On one hand we have the anthropogenic greenhouse gas explanation which says that there is a correlation between C02 and temperature. Temperature trends during the most recent decade have displayed an exact positive correlation. The Skeptical science provides powerful evidence which is supporting this view. On the other hand we have the natural explanation. There is good correlation between temperature and Earth's orbital variations. The historical record shows that the climate system varies naturally over a wide range of time scales. However some expert says that both causes of global warming are linked together, the human impact on climate during this era greatly exceeds that due to known changes in natural processes, such as solar changes and volcanic eruptions. sIn general, climate changes prior to the Industrial Revolution in the 1700s can be explained by natural causes, such as changes in solar energy, volcanic eruptions, and natural changes in greenhouse gas (GHG) concentrations (BBCs evidence supports natural cycles). The developed world is currently responsible for the bulk of world-wide greenhouse gas emissions. It will require the development and use of alternative energy sources, significant changes in lifestyle, and dramatically altered incentive structures that reward environmentally responsible behaviour by people, industries, and governments.

Bibliography:

http://www.theguardian.com/environment/climate-consensus-97-per-cent/2014/jan/09/global-warming-humans-not-sun(New research reinforces human-caused global warming and a climate that'sgreenhouse effect, energy reaching the planet is relatively stable, it's only 300 years, clouds will play in the sensitivity of the global climate to the increased greenhouse effect)

http://www.nwf.org/Wildlife/Threats-to-Wildlife/Global-Warming/Global-Warming-is-Human-Caused.aspx(Global Warming is Human Caused, for hundreds of thousands of years; changes in temperature have closely tracked with atmospheric CO2 concentrations)

http://www.skepticalscience.com/empirical-evidence-for-global-warming.htm(Empirical evidence that humans are causing global warming, the laws of physics tell us thatapproximately 33C (59.4F) cooler than it actually is)

http://news.bbc.co.uk/1/hi/8299079.stm(What happened to global warming, solar charged particles impact us far more than is currently accepted, and we may indeed be in a period of cooling worldwide temperatures that could last another 10-20 years)

http://www.telegraph.co.uk/earth/environment/climatechange/10086694/Tim-Yeo-humans-may-not-be-to-blame-for-global-warming.html(Tim Yeo: humans may not be to blame for global warming, the climate is changing is now overwhelming, the causes are not absolutely clear)